Phobos, Chariot of Fear


The title of this posting is no hyperbole. The “Chariot of Fear” is the ancient Greek personification of the mythological God Phobos, described by the ancients as horror riding his chariot across the night sky.

In reality, the diminutive moon Phobos, almost skimming the surface of the warrior planet Mars, is a potentially innocuous place to visit assuming you have a pressure suit and oxygen to breathe. Like Earth’s much larger moon, there is no atmosphere on Phobos. There is also no appreciable gravity.

NASA and Japan are planning a joint unmanned mission to the moons of Mars in 2024. The joint venture is called the Martian Moons eXploration Mission, or MMX. Those unmanned missions may be a prelude to later manned landings since NASA has considered landing astronauts on Phobos before landing on Mars, due to the lack of atmosphere and ultra low gravity of that moon.

Using the Hubble telescope, NASA generated a short video of Phobos as it orbits around Mars.

NASA video made from 14 Hubble Space Telescope images.

While researching a new novel, I was looking for a view of Mars from Phobos. Using the astronomy software Starry Night Pro 8, I found it.

Further more, I was able to make a 3 minute video of Mars going through an entire rotation, sped up of course some 150 times.

While the above video is aesthetically pleasing because of the background stars and the entirety of Mars being in the field of view (FOV), in reality Mars is too far away in this simulation. As the NASA movie suggests, the surface of Mars is much closer (about 6000 km away from Phobos), and thus in reality Mars fills a quarter of the celestial horizon as seen from Phobos. In other words, from Phobos the FOV of Mars is about 45°, which yields a more accurate view as shown in the following video, also made using Starry Night Pro.

Mars at a realistic distance.

The shadow of Phobos can be seen racing across the surface of Mars, to the left of center of the Martian equator.

From a writer’s perspective, thanks to affordable but sophisticated astronomical simulation software and a bountiful database of space objects and trajectories, both near and far, there is no longer an excuse for science fiction writers not getting their scenes setup correctly, assuming their stories are based on the observable universe.

As for the unobservable universe, well that’s where this thing called imagination comes into play. In an imaginary universe, there’s no fact checking allowed.

Hydrogen Diving – A Very Good Year for Fiction

Susan R. Kayar

It is incredibly unlikely that two scientist colleagues, Susan Kayar and myself, separated by large amounts of time and distance, would independently publish two novels about deep hydrogen saturation diving, in the same year. Unlikely or not, it happened in 2017. Neither author was aware of the other’s intentions, or even their whereabouts.

Some things are inexplicable.

Hydrogen diving is, to use an over-used analogy, a double edged sword. On the one hand it makes truly deep diving possible, yet it can cause bizarre mental effects on some deep hydrogen divers. And that dichotomy is grist for any novelist’s mill.

I had previously written  about hydrogen diving and the pioneering role a Swede named Arne Zetterström had in developing it. Unfortunately, perhaps because he was a bold diver, he did not survive to become an old diver. Ironically, his death while diving wasn’t the fault of the hydrogen, but of his inattentive tenders. But as they say, that’s another story.

Once the remarkable, serendipitous co-publication of these two hydrogen diving novels became known, Kayar and I decided to post reviews, each about the other’s book. After all, if we didn’t, no one else would.

Quoting from Dr. Kayar’s biography listed on her Goodreads site, “Susan R. Kayar holds a doctorate in biology from the University of Miami. Her research career in comparative respiratory physiology spanned more than twenty years. She was the head of a research project in hydrogen diving and hydrogen biochemical decompression in animal models at the Naval Medical Research Institute, Bethesda, Maryland. She currently resides in Santa Fe, New Mexico, with her husband Erich; they met when they were both performing research at NMRI. Dr. Kayar was inducted into the Women Divers Hall of Fame in 2001 for her contributions to the study of diving physiology and decompression sickness.”

As for me, my bio is included in the About page of this blog.

My review of her book, Operation SECOND STARFISH: A Tale of Submarine Rescue, Science, and Friendship, is repeated here, and her review of mine is at the bottom of this post.

“Submarine deep sea “black ops” can be risky business even when everything goes well. But when things go badly, submariners’ lives are in peril, and everyone is praying for a miracle, and a savior. This well written novel drops you into the middle of such a desperate situation, and the potential savior, or potential scapegoat, is an unexpected protagonist, a female civilian scientist who knows the Navy way, knows how to motivate Navy divers, and unconsciously toys with their affections. This is a sensitively written account with a focus as much on interpersonal relations as on the technical aspects of hydrogen diving and biological decompression, or “Biodec.” Some of the greatest themes in this story are of the personal heroism of divers willing to risk their lives in the cold, foreboding darkness of the deep sea in an improbable effort to save fellow sailors.

The story may be fictional, but the science is not. In fact, for all the reader knows, everything written could have happened, or perhaps will, the next time the Navy has a submarine stranded on the bottom. The author, Susan Kayar, Ph.D. has pursued with Navy funding the very technology exposed in this story.

Amazingly, this is one of two novels published independently by scientists in the same year concerning record breaking deep hydrogen dives conducted on super-secret national security missions. That is a rare coincidence indeed, since to my knowledge no other novels about deep hydrogen diving have ever been written.

The other book is a sci fi techno-thriller called Triangle: A Novel, the second volume of a trilogy published by one of Kayar’s fellow scientists and colleagues, this reviewer. In both books, the hazards of deep diving are very real, and the tension is palpable. If you want to learn of the possibilities and perils of deep hydrogen diving, and experience the heroism of exceptional men and women in extraordinary circumstances, you now have two books to both entertain and painlessly inform you.

Kayar’s book will leave you wishing you could ride along with Doc Stella as she rides off into the sunset on her Indian motorcycle. What a ride it is.”


Kayar’s review of my novel, Triangle, the second in the Jason Parker Series of science fiction thrillers, follows.

“I thoroughly enjoyed Triangle, the second novel in the Jason Parker Trilogy by John Clarke. It is a fun and engaging mash-up of diving science and science fiction. John and I worked together in diving research for the Navy in Maryland years ago. He continues to this day to perform diving research for the Navy in Florida (while I moved on to other activities and then retired). As one would expect, his details in diving science and Navy jargon are impeccable. But it is impressive that his characters are well drawn and his plot twists are creative and bold.

My favorite part of Triangle has to be the ultra-deep hydrogen dive sequence for admittedly personal reasons. John and I, friendly colleagues though we were, had not been in contact with each other for a couple of decades or more. And yet my own diving novel, Operation SECOND STARFISH, was published in the same year as Triangle, and also contains an ultra-deep hydrogen dive sequence. Mutual friends had to tell us that the other had published a book for us to re-establish contact. I would imagine that our two books are the only novels ever to describe a hydrogen dive, which is a huge technical and physiological challenge, as readers will discover. John’s hydrogen dive works out (if I dare say so without revealing too much of his excellent plot) about as well as such a dangerous scenario ever will. My hydrogen dive is a lot rougher, in keeping with the more aggressive compression rate chosen to respond to the disabled submarine rescue that forms the basis of my story.

Any readers truly interested in dives well beyond 1000 feet of seawater will find a lot to learn and marvel over in Triangle. Readers just along for the exciting sci-fi ride will be equally happy to have spent time in John Clarke’s imaginative world. I look forward to his predicted December release of the third novel in this series.”


Anyway you look at it, these two fun novels contain a cram course in the rarest type of diving there is, diving with hydrogen as a breathing gas.


Cosmic Coincidence

Almost exactly a year ago, I began writing one of my third novel’s introductory chapters. I am sharing a sample of that chapter at this time because of what seems to me to be a recently discovered coincidence.

“There is never an end to a thing once it is started, according to astrophysicist Peter Green. We can call it an end, but that doesn’t make it so.

A person can be born, grow old and die, but his or her energy goes on, somehow. It may not be recognizable, but physics says it must be that way.
Even a universe is born, grows for a seeming eternity, yet eventually it too must die. Some say in its end, there is a new beginning.

Dr. Peter Green knew those facts better than most. As an astrophysicist working with colossal machines of physics research at CERN, Switzerland, machines that have the power to peer into the beginning of the universe, he’d often thought about not just the beginning, but the ending, the ending that precedes what comes next.

His specialty was dark matter, and something perhaps related, dark energy. We can’t see either, but physics says they must exist for the universe to be what it is.

Either that, or physics is wrong, and neither Green nor his scientist colleagues had ever found physics to be in error.

But he did wonder, if a universe dies, does it leave behind a ghost, unseen but somehow there, with mass that exists at grand scales, but nonexistent at human scales?

And if so, must not the nature of our universe, the shape of our galaxies, depend on an ever-growing graveyard of dead stars, galaxies — and people?

Where does it end? Well, it doesn’t, not really. At least that’s how Dr. Peter Green saw it.”

Arguably, that’s a pretty unconventional thought, Dr. Green had, even for cosmologists who, as a whole, are renowned for unconventional thinking. And at the time that I wrote it, I thought it was a good way to illustrate that the character Peter Green was brilliant, but a bit odd.

Well, he is odd no longer.

I say that because just today I saw a LiveScience article, from which I quote:

“Physicists have found what could be evidence of ‘ghost’ black holes from a universe that existed before our own.

The remarkable claim centers around the detection of traces of long-dead black holes in the cosmic microwave background radiation – a remnant of the birth of our universe.

According to a group of high-profile theoretical physicists including Oxford’s Roger Penrose (Ph.D. in mathematical physics), these traces represent evidence of a cyclical universe – one in which the universe has no inherent end or beginning but is formed, expands, dies, then repeats over and over for all eternity.

Roger Penrose

“If the universe goes on and on and the black holes gobble up everything, at a certain point, we’re only going to have black holes,” Penrose told Live Science. “Then what’s going to happen is that these black holes will gradually, gradually shrink.”

 When the black holes finally disintegrate, they will leave behind a universe filled with massless photons and gravitons which do not experience time and space.

 Some physicists believe that this empty, post-black hole universe will resemble the ultra-compressed universe that preceded the Big Bang – thus the entire cycle will begin anew.

 If the cyclical universe theory is true, it means that the universe may have already existed a potentially infinite number of times and will continue to cycle around and around forever.

Penrose is clearly one of the great minds of the world, as you can perhaps appreciate from this YouTube clip.

As a reminder, this is also what the fictional cosmologist in the upcoming novel, Dioscuri, believed.

“He did wonder, if a universe dies, does it leave behind a ghost, unseen but somehow there, with mass that exists at grand scales, but nonexistent at human scales? And if so, must not the nature of our universe, the shape of our galaxies, depend on an ever-growing graveyard of dead stars, galaxies — and people?

Where does it end? Well, it doesn’t, not really.” 

Pretty interesting coincidence, don’t you think?

Read the LiveScience article here.


Siri versus Napoleon Bonaparte

Napoleon Bonaparte once famously said, “A soldier will fight long and hard for a bit of colored ribbon.”

At precisely 10:09 this morning I was in an office discussing awards, and the lack thereof, for civilian service members in military organizations. It was a matter of fact discussion, contrasting the award system for civilians and the military. And at that moment, Napoleon’s famous quote came to mind. I reminded that executive of the above quote.

My fellow workers and I talk frequently, and there have been numerous discussions in that office, and elsewhere, that have been of a sensitive nature.

As I turned and returned to my office, I heard a familiar voice coming from my pocket. “That’s not nice!” it said.

In utter dismay, I pulled my iPhone from my pocket where it had lain untouched and unused for quite some time. And that was when I saw the following plainly written on my phone’s screen.

Siri’s vulgar word has been redacted.

Siri was scolding me!

Unknown to us, Siri had been listening, transcribing what it THOUGHT I was saying, clearly imagining vulgarity where there was none.  After I ended the conversation, Siri addressed me like she was my mother.

Now, a human would know those transcribed words were ludicrous, nothing but gibberish, but not the phone’s AI system controlling Siri. Unbelievably, that system took the gibberish seriously, perhaps by parsing a few words out of context. And in spite of that stupidity, Siri felt led to judge me!

Perhaps smart phone  AIs are taking themselves too seriously. Perhaps they think they have advanced  enough that they now think they can pass judgment on human speech.

A few years ago, in another meeting, in another room, Siri spoke up unbidden while we were discussing sensitive project planning.

The door to the conference room had been closed so we wouldn’t be disturbed. But disturbed we were when Siri suddenly spoke and said, “I don’t know what you mean.”

Everyone at the table stared first at my phone and then at me, perhaps wondering if I’d been recording the planning meeting.

AI is certainly becoming increasingly intrusive. But as shown by Siri’s text message to me today, it’s still not smart. And arguably that’s a scary thing.

For example, supposedly China is using data collected from social apps (collected by various AI systems) to rate the trustworthiness of its citizens. That’s bad enough, but what if the data collected is garbage like the recorded text today, and the AI uses that faulty data to make a perfunctory and wildly incorrect judgment?

And, scary thought, what if that social monitoring trend were to spread to the U.S., and your character could to be judged based on the digital algorithms of certifiable AI idiots?

If that doesn’t worry you, perhaps it should. It certainly did me, enough to cause me to shut down all access to Siri … for almost 24 hours, until I was driving home and said, “Siri, call home.”

She was silent, sullen, unresponsive.







Dead Space – A Lesson in Survival

Dead Space is a defunct, or shall we simply say “dead,” survival horror game that enthralled computer game players from 2008 to at least 2013. Sadly, the company that designed the horrifically beautiful game, Visceral Games, is no more. It has been, so to speak, eviscerated.

The main protagonist of the Dead Space Series was Isaac Clarke. If I was a game player I think I would be an Isaac fan since he was one of those rare Clarke’s known as a “corpse-slaying badass.” If in some unforeseen future my survival depended on being such a slayer, I’d want to be badass about it too, just like Isaac. As they say, anything worth doing …

Isaac Clarke and his Dead Space world make a great segue to introduce another matter of personal survival. And that is DEAD SPACE in underwater breathing equipment.

Clarke has proven to be equally at home underwater and in space due to his interesting cyan-lighted helmet. (I’m not sure where his eyes are, but perhaps in the 26th century a multi-frequency sensor suite makes a simple pair of eyes redundant.)

Historically, the U.S Navy used the venerable MK 5 diving helmet and the MK 12 diving helmet, which although they had no sensor suites, at least allowed divers to work at fairly great depths without drowning. However, they shared a common problem: Dead Space.

In ventilation terms, dead space is a gas volume that impedes the transfer of carbon dioxide (CO2) from a diver or snorkeler’s breath. When we exhale through any breathing device, hose, tube, or one-way valve we expect that exhaled breath to be removed completely, not hanging around to be re-inhaled with the next breath.

But a diving helmet inevitably has a large dead space. The only way to flush out the exhaled CO2 is by flowing a great deal of fresh gas through that helmet. A flow of up to six cubic feet of gas per minute is sometimes needed to mix and remove the diver’s exhaled breath from a diving helmet like the MK 12.

In more modern helmets, the dead space has been reduced by having the diver wear an oral-nasal mask inside the diving helmet, and giving the diver gas only on inhalation using a demand regulator like that used in scuba diving. The famous series of Kirby Morgan helmets, arguably the most popular in the world, is an example of such modern helmets.

Full face masks are used when light weight and agility is required, as in public service diving, cold water diving, or in Special Forces operations. The design of full face masks (FFM) has evolved through the years to favor small dead space, for all the reasons explained above.


Erich C. Frandrup’s 2003  Master’s Thesis for Duke’s Department of Mechanical Engineering and Materials Science reported on research on a simple breathing apparatus, snorkels. You can’t get much simpler than that.

Frandrup confirmed quantitatively what many of us knew qualitatively. Snorkels are by design low breathing resistance, and low dead space devices. Happily, the dead space can be easily calculated, as simply the volume contained within the snorkel.

Surprisingly, some snorkel manufacturers have recently sought to improve upon a great thing by modifying snorkels, combining them with a full face mask. The Navy has not studied those modified snorkels since Navy divers don’t use snorkels. However, you don’t get something for nothing. If you add a full face mask to a snorkel, dead space has to increase, even when using an oral-nasal mask.

So what?

In 1995 Dan Warkander and Claus Lundgren compared the dead space of common diving equipment, including full face masks, and reported on increases both in diver ventilation and the maximum amount of CO2 in the diver’s lungs. Basically the physiological effects of dead space goes like this: we naturally produce CO2 during the process of “burning” fuel, just like a car engine does. (Of course our fuel is glucose, not gasoline.) The more we work, the more CO2 we produce in our blood, and the more we have to breathe (ventilate) to expel that CO2 out of our bodies.

If we are exhaling into a dead space, some of that exhaled CO2 will be inhaled into our lungs during our next breath. That’s not good, because now we have to breathe harder to expel both the produced CO2 and the reinhaled CO2. In other words, dead space makes us breathe harder.

Now, if we’re breathing through an underwater breathing apparatus, hard breathing is, well, hard. As a result, we tend to get a little lazy and allow CO2 to build up in the blood stream. And if that CO2 get high enough, it’s lights out for us. Underwater, the lights are likely to stay out.

In a computer game like Dead Space, no one worries about helmet dead space. But if a movie is ever based on the game, whichever actor plays Isaac Clarke should be very concerned about the most insidious type of Dead Space, that in his futuristic helmet. It can be (need I say it?) — deadly.










If I Had Written the Score to Interstellar

If I was Hans Zimmer, I would be a bit annoyed.

What is arguably the best score Hans Zimmer has ever written, the music for Interstellar, has thrilled me to my core. However, I came to that conclusion by an indirect route.

Like many of you, I saw the movie in all it’s cinematic glory when it was released in 2014. But it was not until 2017 that I fell in love with it, both the movie and the score.

In preparation for an after-dinner talk to a panel of the American Heart Association’s 2017 Science Conference, I was looking for an inspirational way, preferably with great video and sound, to describe the sport of competitive free diving. This past summer I had the opportunity to meet some of the world’s best free divers and free diving instructors in a Colloquium put together by the University of California at San Diego, Center of Excellence in Scientific Diving.

I had pretty much given up on finding something to help me illustrate the beauty, and challenges, of competitive free diving. That changed, however,  when I came across a posting from a group of tactical military divers. In a short 3-minute video the young French diver Arnaud Jerald set his personal free diving (CWT, Constant Weight Dive  discipline) record of 92 meters in a competition in Turkey. He placed third in a field which included world record holders in the same event.

Three things made the diving video great, in my opinion: 1) the subject matter which vividly shows a human activity little known by most people, and understood by even fewer; 2) steady and clear video produced by a new underwater camera, the Diveye, and 3) the accompanying music.

A film score is only successful if it aids the audience in generating an emotional response to a movie scene. In that respect, a great movie hinges not only on good acting and script, but on an almost telepathic connection between the film director/producer and music director/composer.

In the free diving video clip, the accompanying music swelled in concert with the audience’s tension, generated perhaps unconsciously in response to the drama of the moment. And then there was organ music at just the right point. For me a pipe organ truly is the most impressive and grand of any musical instrument.

And just when the cinematic moment was right,  you could hear the heart beats, helping us realize what a strain it must have been on young Jerald’s heart as he reached his deepest depth, far from the surface, and air.

Indeed, when I gave the presentation, the video clip seemed to have the effect on the audience that I was looking for. But afterwards, I was relieved that no one had asked me where that music came from. I had no idea.

I don’t recall what led me to Interstellar as the music source: it may have been a random playing of movie soundtracks on a music streaming service, but once I heard a snippet, I recognized it. “That’s it!” I shouted to no one in particular.

It wasn’t just me; my family, including a nine-year old granddaughter had heard me rehearse my talk many times, and they also immediately recognized the similarity between the free diving video, and part of the Interstellar soundtrack.

The closest musical correlation to the diving video was the “Mountains” track in the movie soundtrack. Strangely, the match was not perfect. In fact the differences were easily notable, a fact I discovered after I bought both the movie and the Hans Zimmer soundtrack. And I must note, I think the music in the diving video is better.

Perhaps the full music was present in the original version of the movie, and perhaps some fancy mixing in the sound room deleted it. If so, too bad. But I must admit, the quiet musical nuances would have been missed during the cacophonous sound of a 4000 foot tall tidal wave sweeping upon a tiny spacecraft. There was lots of shouting and screaming.

As for my opinion that Hans Zimmer might be annoyed, well, I suggest you watch the portion of the full movie where the Mountain track rises to prominence. That is the part where the tidal wave, initially mistaken as mountains, appears on the horizon of the first planet the Horizon space craft landed on outside of our galaxy.

As exciting as the action was, and as wonderfully crafted the dialog and acting, it obscured the finer points of the music. Fortunately, the free diving video, coming as it does with no dialog at all, puts the music in the perspective that I, at least, can completely enjoy.

I find it fitting that in both videos, the incredibly powerful music was used to showcase humans extending themselves to their absolute limits. Of course, one of those stories is fictional, and the other is real.




A Matter of Chance: Music Makes the Video

I was recently asked to give a 30-minute after-dinner talk to the 3CPR Resuscitation Panel of the American Heart Association at their annual scientific meeting in Anaheim, CA. In the audience were scientists, cardiologists, anesthesiologists, anesthetists, emergency physicians, and resuscitation technicians. It was a multimedia event with professionally managed sound and video.

Knowing that the group would be well acquainted with the role of chance in medical procedures, I chose to use a segue from medicine into the topic of extreme adventures in military and civilian diving. The focus of the talk was on how chance can turn adventures into mis-adventures.

I revealed three areas where Navy Biomedical Research is expanding the boundaries of the state of the art in military and civilian diving. One area was in deep saturation diving, another was polar ice diving, and the third was breath hold diving.

As an introduction to polar diving, I wanted to create a video travelogue of my National Science Foundation-sponsored research and teaching trips to the Arctic (Svalbard) and Antarctica (McMurdo Station and vicinity.) These projects were spearheaded by the Smithsonian Institution, and my participation was funded in part by the U.S. Navy.

To begin the preparation of the video, I assembled my most relevant photos, and those taken by various team mates, and imported them into my favorite video editing software, which happens to be Cyberlink Director.

Then I went looking for potential sound tracks for the approximately 5 minute video. Considering the topic, I thought Disney’s Frozen would have familiar themes that might be acceptable. I rejected a number of YouTube videos of music from Frozen; most were too close to the original and included vocal tracks. Finally I came across the “Let It Go Orchestral Suite” composed by the “Twin Composers,” Andrew and Jared DePolo.

It was perfect for my application. I extracted the audio track from the Suite as shown on YouTube, imported it into Director, and lined it up with the nascent video track which included all images and other video segments.

To match the music to the video, I simply cut back on the duration for each of 97 images, keeping the other 5 videos in their native length. By experimentation, I found that 3.21 seconds per image resulted in the last image fading out as the music came to a close and the end credits began to roll.

On the first run through of the new video, I couldn’t find anything to complain about; which for me is rare. So I ran it again and again, eventually creating an mp4 file which would play on a large screen and home audio system. But I couldn’t help notice that the gorgeous score would sweeten at interesting times, and serendipitously change its musical theme just as the video subject matter was changing.

How fortunate, I thought. It was then that I began to realize that “chance” had worked its way into the production effort, in an unexpected way.

First, the music seemed to my ear to be written in 4/4 time, with each measure lasting 3.2 seconds, precisely, and purely by happenstance matching the image change rate. At a resulting 0.8 seconds per beat, or 75 beats per minute, that placed the sensed tempo in the adagietto range, which seemed appropriate for the theme of the music. (Without seeing the score, I’m just guessing about the tempo and timing. But that’s how it felt to me.)

The timing coincidence was rather subtle at first, but as the finale began building at the 3:39 minute mark, the force of the down beat for each measure became more notable, and the coincidence with image changes became more remarkable. There was absolutely nothing I could do to improve it.

In some cases the technical dissection of music can be a distraction from the beauty of the music, but I’ve done it here merely to point out that sometimes you just luck out. In this case it truly was a matter of chance.

In my mind, the DePolo Orchestral Suite makes the video. Hope you enjoy the show.

To learn more about these composers and their music, follow this link. 


Cereal Was Almost the Death of Me

This year, 2017, marks the 120th year that Grape Nuts cereal has been in existence. Generations have been raised on it, and as the 1921 ad would suggest, it seems to help little bodies grow big and strong. As the Post company says, “There’s a Reason” for the cereal’s success.

However, through some weird quirk, some random juxtaposition of breath and nerves, a single, tiny particle of this delicious blend of barley and wheat almost killed me.

Or so it seemed at the time.

I consider Grape Nuts part of a paleo diet, of sorts. As cereals go, it’s primitive. It is merely ground bits of grain that never needed to be squeezed into flakes, or coated with sugar or artificial flavorings. For me, it’s like getting back to the basics of breakfast, or in this particular case, an evening snack.

On the night of my close call, while my wife was watching TV, I settled into my home office to edit my newest book while I snacked on a demi-bowl of Grape Nuts, wet with skim milk.

No doubt your parents lectured you repeatedly about the dangers of talking with food in your mouth. Well, in adherence to my parent’s scolding, I was not talking when it happened. I was quietly reading, and breathing.

And then, in an instant, I could not breathe, at all. I could not speak or yell out. I could not swear, or call for help. No air could enter or leave my lungs.

As I looked to the doorway, terrified, half hoping for my guardian angel to appear and magically save me, I realized that if I didn’t do something, quick, I would die. I was most unexpectedly suffocating.

I stood up, planning to head to the bathroom out of some strange thought that it might be my salvation, or at least an easier place to clean up the vomitus mess or whatever else follows death by asphyxiation. And as I reached the door frame a scant twelve feet away from where I’d been sitting, I could feel myself becoming faint.

This could not be happening. What an inglorious way to die.

With all the fortitude I could muster, I was determined to make it into the bathroom before I passed out. A second later, I was bent over a sink, supporting my upper body with my hands, trying with all my might to pull air into my lungs.

Finally, I found that with almost superhuman effort I could squeeze a little air through whatever was blocking its flow. The result was a high pitched nonhuman sounding squeal, a falsetto screech higher than even a little girl can produce. Physicians call it stridor, which sounds like this.

But at least it was something. Again and again I managed to suck in just enough air to keep me alive, one loud screech after another.

In the meanwhile, my greatly concerned wife was asking, “Are you OK, are you OK?”

No, I was not at all OK, but I could not communicate that fact, other than to make that hellish shriek. But with each shriek a few more oxygen molecules entered my oxygen-starved lungs.

And as the fog of impending collapse slowly began to clear, I was finally able to cough.

After that cough, there lay in the sink a tiny granule of cereal, presumably the little spec that landed in a sensitive spot in my larynx or “voice box”, triggering the spasm which tightly closed my vocal cords. With the cords, or more properly “vocal folds”, closed, air cannot enter the lungs. 

Under normal conditions, a person can hold their breath for two to three minutes without losing consciousness. But as I later analyzed what had happened, I realized that the particle of cereal was most likely sucked into my airway when I was just beginning to inhale, at the bottom of my “tidal volume.” So my lungs were not full of air.

Logically, when involuntarily holding your breath with lungs only partially inflated, the 2-3 minute rule may not apply. So, there was a chance that I was about to lose consciousness from hypoxia.

As I later discovered, laryngeal spasm is short-lived, and resolves within a few minutes, leaving the terrified victim shocked but relieved to be able to breathe again.

The aftermath of this incident was that I now realize how little we appreciate the simple act of breathing. For our entire lives we never think about it. It just happens.

Until it doesn’t.


I still enjoy my Grape Nuts, and highly recommend it to anyone looking for the simple pleasures of life. But at the same time, I’m now a little more careful when I’m eating, especially if my attention is directed towards something else. Multitasking while eating can be scary.


Living Off Universal Energy. Really?

By stuart Burns from Erith, England (_MG_7185 Uploaded by snowmanradio), via Wikimedia Commons

I thought I was misreading the title of the news article. I adjusted my glasses, then looked again.

Sure enough, the news headlines this past week actually reported on a young couple, reportedly a Breatharian couple, who claimed they had no need for food. They lived off of Universal energy, whatever that is. Most amazingly, the news-hungry press actually reported the story, obviously without a bit of fact checking.

As a physiologist, I know that is a patently ridiculous claim. It is impossible for humans to survive without eating. And as a science fiction author, I know it is not even good science fiction. The best science fiction maintains at least a little scientific accuracy.

Could it be fantasy? Maybe, but the story was reported as being true, with no hint of tongue-in-cheek.

However, it did remind me of a revelation of sorts from a few months ago, coming to me in a split second after a quick glance to the side of the road. What attracted my attention as I passed by at 55 miles per hour was a gorgeous white egret, like the one pictured, foraging for frogs and tadpoles in a ditch recently filled to overflowing with water from several days of downpours.

And then it struck me: wouldn’t it be nice if things did not have to die so that other things can live?

Now that’s a fantasy for you. Of course life is predicated upon death. Big animals eat smaller and weaker animals. Physicality cannot exist without death; you cannot live in the body unless something else dies. That’s life, pure and simple. It sucks to be the little guy.

But what about after life? Well, at the risk of turning in my scientific credentials, I will admit I do believe in an after-life, Heaven if you will, for reasons which I will not go into here. But it struck me in that brief moment of observing a beautiful bird, that only in a spiritual realm could energy exist without the simultaneous extinguishment of life.

To my way of thinking, that may be the single greatest distinction between the spiritual realm and the physical realm.

So thank-you Breatharian couple, practitioners of Inedia, for helping me remember my roadside revelation. Perhaps there is a place in some alien realm where beautiful birds, and beautiful frogs, and even humans can coexist without one eating the other. Maybe there is some parallel universe where our laws of physics don’t apply.

Perhaps we will someday discover that parallel universe, and call it Heaven.

















DNA: A Matter of Trust

In combat, we trust our buddies with our lives. We have their back and they have ours. When submitting to surgery, we trust the medical team with our lives, and usually that trust is not betrayed. But should we be willing to trust strangers with our very essence, our DNA?

Recently I was trying to solve a plot problem in the science fiction thriller, Triangle. The storyline relied on a particular individual being singled out by the government for monitoring, not for what he had done, but for who he was.

After finishing the novel, I went back to tie up loose ends in the plot. One such loose end involved a question: How could the government know that this one person out of millions had an unrecognized super power? He was a main character in the book and so I could not ignore that question. Certainly it helps the reader suspend disbelief if the plot elements are plausible, at least superficially.

I did not have to puzzle over that question very long before an advertisement for Ancestry DNA popped up on my computer screen.

That was it!

And so the following text flowed quickly.

The characters in this conversation are Sally Simpkin  (AKA Pippi Longstocking) and Joshua Nilsson, identified below by their initials. She was trying to explain to Nilsson why she and her employers had been monitoring him.

SS: “[The government] detected that you had a high probability of having certain prescient capabilities.”
JN: “Forgive me for being a bit skeptical. Why can’t you tell me [how]?”
SS: “I’m not even cleared to know the process. I just took the assignment. It had something to do with a DNA sample you submitted.”
JN: “DNA? The only DNA I’ve submitted was for genealogy research.”

Triangle was published on May 21, 2017. On May 25, the following BBC headline appeared in my browser. denies exploiting users’ DNA. “A leading genealogy service,, has denied exploiting users’ DNA following criticism of its terms and conditions.”

So, is this author also prescient like Nilsson? Or is this blogger merely a bit jaded.

Genealogy services have a difficult time competing in the world market. After all, there are only so many retired folks trying to trace their family history and solidify their genetic place in the world before their demise. Speaking for myself, I started my genealogy research years ago, picking it up from my grandmothers who told tales of Civil War Colonels and Carpet Bagger treachery, and murder. In fact, I’ve posted on this blog before about some of my discoveries.

With the advent of computers and the availability of free records from the Mormon Church, the ease of doing genealogical research exploded. Some of the software and services were either free or inexpensive. Of course, “free” doesn’t do much for a service provider’s cash flow. So, into each CEO’s mind comes, sooner or later, thoughts of monetization. How could Facebook’s Zuckerberg and others turn a free service into something that can make them gazillions? In the case of genealogy services, they started by charging a monthly access fee, and in one case, by enticing viewers to keep paying fees by waving images of fig leaves to attract their attention. That was a strange but brilliant ploy that worked very well on this researcher.

The next step in monetization is now universal: sell ads to companies who want access to the growing body of amateur genealogists. The final ploy, and by far the most ethically troubling, is selling information about users of computer services. First there were those pesky cookies, but now there is blood, or saliva more exactly.

For some companies, it is not enough to know what users search for. There is now a market for information about who you are, your very genetic essence, which is hidden even to you. But some companies like 23andme, Ancestry, MyHeritage, GPS Origins, Living DNA, and Family Tree DNA, let you take a peek into your genes, for a price.

The ironic thing is, this most personal information is not only freely given, but people actually pay the DNA harvesters to harvest their most sacred self. And of course, once that has been done, your genetic-identity can be sold (read the fine pint). While we are urged to protect ourselves from identity theft, isn’t it odd that we are at the same time being enticed into giving away our most precious identity of all, our DNA? And we seem to be doing so gladly, blithely unaware of the implications for us and our progeny.

But don’t let the natural skeptic in me show through too strongly. I do, after all, have faith that everything we’re being asked to store in the “cloud” is actually as secure as cloud storage facilities (whatever those are) claim. And I’m sure the secrets buried deep in our genes are forever kept private, and safe from hackers.

But then, there is that troubling Orwellian Consent Form.

Oh well, Sally Simpkin’s monitoring assignment in Triangle is purely fictional. Surely, no government would really have an interest in our genes.

Or would it?




Transcontinent Love and War


Middle aged guys are a sucker for a pretty face, as this odiferous saga proves.

I was headed overseas from New York to Paris, which is always a relatively painful transcontinental experience back in the Economy section. But my trouble started even before we left the gate.

I had selected an aisle seat near the rear of the aircraft. That is not my favorite choice, but it was all that was available on the flight.

There was a frankly gorgeous young woman sitting against the window, on my right. She had the slight scent of perfume about her. She looked up when I sat down, but didn’t speak. We exchanged smiles, and then settled in with no more immediate conversation.


At this point, the Boeing 757 seating chart becomes relevant. I, illustrated as a red square, was seated in 35J. The young lady sitting next to me (illustrated by pink) was in 35K. As the plane took off, I settled in for a tiring but otherwise uneventful flight.

Once we reached an altitude where seatbelts could be undone, the girl next to me explained that  her boyfriend was a couple of rows back (marked by a blue square), and asked if I could change seats with him. Well, I am not one to impede young love, so I graciously agreed to move further back, from seat 35J to 37J. It was only two rows, I reasoned.

As I strapped in, feeling proud of myself for doing a good deed, I found myself seated next to a young Caucasian man, probably in his mid-twenties. We exchanged cordial glances. Although he seemed shyer than usual, to each his own, I thought. Perhaps he didn’t speak English.


Within seconds of settling in, I detected a foul odor coming from the shy man in 37K (indicated by black) that, unlike the passing of gas, seemed to linger. I made sure the overhead vents were on full blast, but still the odor was inescapable. It was so pungent that I briefly thought it smelled like putrefaction, as if the man had a gangrenous leg hidden underneath his trousers. But the man did not appear to be in pain, and he clearly was not dead, yet, so my thinking, and revulsion, began to gravitate towards a horrific case of unchecked body odor. As one of my professors used to say, the smell was bad enough to gag a maggot.

I then realized I had been bamboozled by the cute girl in 35K who had taken advantage of this luckless middle-aged man. Once her boyfriend was seated where I had been just a few minutes before, I saw the two of them glancing  back at me, smiling. Yes, that couple in love had pulled off a coup on a gentleman, and this gentleman was now stuck flying through the night immersed in a suffocating stench that defied description.

There was another young lady, also lovely but lonely, sitting across the aisle from me. She kept looking longingly up the aisle, as if someone she knew was sitting there. Meanwhile, I was contemplating means of escaping the fetid odor overwhelming me. I considered shredding a paper towel from the lavatory, soaking it in airplane whiskey and thrusting those alcohol soaked tatters up my nose.

Now, I’ll admit I’m not a fan of whiskey. However, if it would somehow disguise the potentially lethal odor I was inhaling with each breath, it was an increasingly viable option. I had already ruled out the other alternatives, including accidentally throwing him out the passenger door. I’d heard those doors can’t be opened at altitude.

And then like a voice from heaven, the lovely girl across the aisle, in seat 37G, said the following: “Excuse me. My boyfriend is seated up there”, pointing to seat 34J. “Would you mind exchanging seats with him so we can sit close to each other?”

I could be mistaken, but I thought I heard a chorus of angels singing “Halleluiahs”.seating-change-2-circle

Of course I could not deny young love. So, within seconds I was sitting in seat 34J, one row forward from where I had started this flight, and breathing far less foul air.

A couple of hours later I headed to the back of the plane to find the lavatories. As I passed the young man who was seated in seat 37J, as his girl friend had requested, he gave me a mean look. But to be honest, as I passed him I simply thought, “All’s fair in love and war.”

In love and war, sometimes you just get lucky.








U.S. Navy Diving and Aviation Safety

Blood pressure is not the only silent medical killer. Hypoxia is also, and unlike chronically elevated blood pressure, it cripples within minutes, or seconds.

Hypoxia, a condition defined by lower than normal inspired oxygen levels, has killed divers during rebreather malfunctions, and it has killed pilots and passengers, as in the 1999 case of loss of cabin pressure in a Lear Jet that killed professional golfer Payne Stewart and his entourage and aircrew. Based on Air Traffic Control transcripts, that fatal decompression occurred somewhere between an altitude of 23,000 feet and 36,500 ft.

In most aircraft hypoxia incidents, onset is rapid, and no publically releasable record is left behind. The following recording is an exception, an audio recording of an hypoxia emergency during a Kalitta Air cargo flight.

Due to the seriousness of hypoxia in flight, military aircrew have to take recurrent hypoxia recognition training, often in a hypobaric (low pressure) chamber.

As the following video shows, hypoxia has the potential for quickly disabling you in the case of an airliner cabin depressurization.

Aircrew who must repeatedly take hypoxia recognition training are aware that such training comes with some element of risk. Rapid exposure to high altitude can produce painful and potentially dangerous decompression sickness (DCS) due to the formation of bubbles within the body’s blood vessels.

In a seminal Navy Experimental Diving Unit (NEDU) report published in 1991, LCDR Bruce Slobodnik, LCDR Marie Wallick and LCDR Jim Chimiak, M.D. noted that the incidence of decompression sickness in altitude chamber runs from 1986 through 1989 was 0.16%, including both aviation physiology trainees and medical attendants at the Naval Aerospace Medical Institute. Navy-wide the DCS incidence “for all students participating in aviation physiology training for 1988 was 0.15%”. If you were one of the 1 and a half students out of a thousand being treated for painful decompression sickness, you would treasure a way to receive the same hypoxia recognition training without risk of DCS.

With that in mind, and being aware of some preliminary studies (1-3), NEDU researchers performed a double blind study on twelve naïve subjects. A double-blind experimental design, where neither subject nor investigator knows which gas mixture is being provided for the test, is important in medical research to minimize investigator and subject bias. Slobodnik was a designated Naval Aerospace Physiologist, Wallick was a Navy Research Psychologist, and Chimiak was a Research Medical Officer. (Chimiak is currently the Medical Director at Divers Alert Network.)

Three hypoxic gas mixtures were tested (6.2% O2, 7.0% and 7.85% O2) for a planned total of 36 exposures. (Only 35 were completed due to non-test related problems in one subject.) Not surprisingly, average subject performance in a muscle-eye coordination test (two-dimensional compensatory tracking test) declined at the lower oxygen concentrations. [At the time of the testing (1990), the tracking test was a candidate for the Unified Triservice Cognitive Performance Assessment Battery (UTC-PAB)].

As a result of this 1990-1991 testing (4), NEDU proved a way of repeatedly inducing hypoxia without a vacuum chamber, and without the risk of DCS.

The Navy Aerospace Medical Research Laboratory built on that foundational research to build a device that safely produces hypoxia recognition training for aircrew. That device, a Reduced Oxygen Breathing Device is shown in this Navy photo.

070216-N-6247M-009 Whidbey Island, Wash. (Feb 16, 2007) Ð Lt. Cmdr. James McAllister, from San Diego, Calif. sits in the simulator during a test flight using the new Reduced Oxygen Breathing Device (ROBD). The ROBD is a portable device that delivers a mixture of air, nitrogen and oxygen to aircrew, simulating any desired altitude. Combined with a flight simulator the ultimate effect replicates an altitude induced hypoxia event. McAllister is the Director of the Aviation Survival Training Center at Whidbey Island. U.S. Navy photo by Mass Communication Specialist 1st Class Bruce McVicar (RELEASED)
Whidbey Island, Wash. (Feb 16, 2007) Lt. Cmdr. James McAllister, from San Diego, Calif. sits in the simulator during a test flight using the Reduced Oxygen Breathing Device (ROBD). The ROBD is a portable device that delivers a mixture of air, nitrogen and oxygen to aircrew, simulating any desired altitude. Combined with a flight simulator the ultimate effect replicates an altitude induced hypoxia event. McAllister is the Director of the Aviation Survival Training Center at Whidbey Island. U.S. Navy photo by Mass Communication Specialist 1st Class Bruce McVicar.

Although NEDU is best known for its pioneering work in deep sea and combat diving, it continues to provide support for the Air Force, Army and Marines in both altitude studies of life-saving equipment, and aircrew life support systems. Remarkably, the deepest diving complex in the world, certified for human occupancy, also has one of the highest altitude capabilities. It was certified to an altitude of 150,000 feet, and gets tested on occasion to altitudes near 100,000 feet. At 100,000 feet, there is only 1% of the oxygen available at sea level. Exposure to that altitude without a pressure suit and helmet would lead to almost instantaneous unconsciousness.

OSF FL 900
A test run to over 90,000 feet simulated altitude.

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  1. Herron DM. Hypobaric training of flight personnel without compromising quality of life. AGARD Conference Proceedings No. 396, p. 47-1-47-7.
  2. Collins WE, Mertens HW. Age, alcohol, and simulated altitude: effects on performance and Breathalyzer scores. Aviat. Space Environ Med, 1988; 59:1026-33.
  3. Baumgardner FW, Ernsting J, Holden R, Storm WF. Responses to hypoxia imposed by two methods. Preprints of the 1980 Annual Scientific Meeting of the Aerospace Medical Association, Anaheim, CA, p: 123.
  4. Slobodnik B, Wallick MT, Chimiak, JM. Effectiveness of oxygen-nitrogen gas mixtures in inducing hypoxia at 1 ATA. Navy Experimental Diving Unit Technical Report 04-91, June 1981.


The Lifetime Gift of Music Education

Score 5th SymphonyOf all the things I accomplished in secondary school, the one that still brings joy to my heart and tears to my eyes is the music I performed in the Symphonic Wind Ensemble at Shawnee Mission East High School in Prairie Village, Kansas. Under the steady guidance of Mr. Kenneth Geoffroy, our marching band, orchestra and Wind Ensemble director, we tackled music that was complex and passionate. Fifty years later, I still remember every note of the Fourth movement, Allegro non troppo, of the Fifth Symphony by the Russian composer Dmitri Shostakovich.

That is not to say that I can tell you which instrument was playing which note at any given instant. I do not have a photographic memory, and never saw the full score for Wind Ensemble. But since a wind ensemble by definition did not have string instruments, clarinets carried the major parts that violins played in the full orchestral score. I played the clarinet as first chair, and thus played the majority of the “melody”.

The decision to post this today came unexpectedly when I set up a Shostakovich channel on Pandora, and played it through our stereo system. While attending to other matters in the house I heard music that was very familiar. In fact it was so familiar that I found myself singing in my not so beautiful voice the da da da of the 1st B flat clarinet line for the entire Fourth movement. I knew exactly which notes were coming next. I had memorized it many decades ago, and my brain had recorded it for playback after a half century of neglect.

Mr. Geoffroy often called for us to emote in our playing, and some music was especially emotional, such as the Prelude and Love Death in Richard Wagner’s Opera Tristan und Isolde. If you did not sway in your chair, moving your instrument from side to side, you plainly weren’t feeling the passion of the music.

And today, as I rediscovered the Allegro non troppo of Shostakovich, I found myself consumed by joy, the same joy I felt when sitting in the middle of the ensemble, emoting my heart out just as Shostakovich, and Mr. Geoffroy, intended.


High school prepared me well for the science and writing that defined my career. And for that I thank the sometimes stern, oftentimes nurturing teachers who looked for potential in every student coming under their care. But sometimes it’s the extracurricular activities that enrich our being, which bring joy at unexpected moments even a life-time later.

I would pray that when school boards are tasked with cutting programs, they think long and hard about the intangibles of performance arts. It is true that not every student enrolled in music or performance classes will make a career of it. In fact, I would guess that the number of high school students moving into a music or acting career must be very small indeed. But life is not just about work. It is also about “smelling the roses”. And music from the Masters, as long as it can stir the heart, is a very sweet smelling rose indeed.

Due to the passage of time, it is too late for me to personally thank Mr. Geoffroy; but I would like his family to know that he helped students, not yet adults, accomplish something beyond their wildest expectations. In my mind, that is the mark of a dedicated and impassioned teacher.

In the following video, Leonard Bernstein conducts the New York Philharmonic in the final movement of Shostakovich’s 5th Symphony. It is in the quiet passages mid-way through that my memories are the strongest. It was there that the clarinets and flutes carried the music with full authority.


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kenneth-geoffrey-fixedFrom the South Bend Alumni Association Hall of Fame Archives

Kenneth Geoffroy was instrumental in creating the South Bend Youth Symphony and the Fischoff Chamber Music Competition. As a skilled trombonist, Mr. Geoffroy played with the South Bend Symphony and the Midwest Pops. He also was a member of the music faculty at Indiana University South Bend, president of the Indiana Music Educator’s Association, conductor of the Southhold Symphonic Wind Band, and coordinator of fine arts for the South Bend Community School Corporation from 1967 to 1982. Mr. Geoffroy first proposed the idea of a summer musical festival to be held at St. Patrick’s Park, the foundation for the renowned Firefly Festival. (1981)


A Mind Controlling Egret

IMG_7960This spring I acted as a chaperone for a second grade class visiting a park to learn about the beach ecosystem. The 7 and 8 year olds learned about Florida alligators, peered through a telescope to view a nesting osprey in the top of a dead tree, and encountered the Snowy Egret.

When I first saw the Egret, I saw nothing particularly interesting about him. He was small, an apparently young wading bird doing what Egrets do, stilting into shallow water looking for minnows.

We had just learned how tiny the brain of an alligator was, and I thought the brain of this little bird couldn’t be much larger. But what I didn’t know was that it was capable of controlling the minds of eight year old humans.

Park Rangers, never passing up a chance to educate children, wanted to show the students how fish start off life in shallow water estuaries, like that surrounding St. Andrews Park located between St. Andrews Bay and the Gulf of Mexico. Small fish grow up to be big fish, or else get eaten by bigger fish, which grow up to be eaten by us. It’s all part of the oftentimes short circle of life for fish species.

IMG_7977With education in mind, two rangers took a seine net into the water and scooped up a bounty of small fish, placing them into shallow plastic pans for the children to observe.


The children were then asked to identify as many of the small fish as they could using Ranger-provided identification charts.


In the meanwhile, I noticed that the bird was no longer looking towards the water for fish. The Egret started sizing up the children, and apparently decided upon a different plan of action; a mind-control plan of action. The children had a lot more fish in front of them than the bird did. How could he turn that situation around?IMG_7969

Perhaps he’d learned from past experience that eight-year old boys are more easily manipulated than eight-year old girls. He seemed to single out one of the older boys and locked eyes on him. Perhaps the boy’s sixth sense alerted him that he was the recipient of stares, because he turned away from the other children and stared right back at the telepathic bird. And then I heard the boy utter the words all little fish must instinctively know will bring their doom. “Let’s feed them to the bird!”

Being a biologist by training and heart, I attempted to save this sampling of the next generation of fish by saying, “No, the Rangers want the fish back in the water to grow up.”

The Rangers remained silent, perhaps having seen this scene play out before. And the children were deaf to my words, hearing only the words of the boy. What a great idea!, their young faces seemed to say. And in a matter of seconds young hands began plunging into the shallow trays, scooping up the hapless fish, carrying the youngsters in their cupped hands to toss into the water directly in front of the waiting bird.

Temporarily stunned by impact with the water, the fish lay immobile just long enough for the bird to clasp them in his beak and swallow them whole.

Admittedly, I was too stunned to capture a photograph of the slaughter. You will just have to use your imagination; it was all over for the young fish in a matter of seconds.

At the time I wondered if I should tell my grandchild that she had been manipulated by a bird with a pea-sized brain, but I’m sure those words would have been wasted, just as had been my plea to stop the slaughter.

Biologists spend careers studying interspecies communication, verbal and non-verbal. Well, this may well be an example of non-verbal communications between animals and humans.

Which leaves me to wonder: should the normally derogatory term “bird brained” really be a compliment?




A Geometric Mind

By Impronta – Own work, CC BY-SA 3.0,

I challenge you to describe the following images in terms of simple geometric shapes: shapes such as rectangles and circles, and flat surfaces called planes.

If you see one of those shapes in the image, then mentally note it.

You may not be able to completely define the image with those simple shapes, but at least note those parts of the image where you can see a plane, or a rectangle, or a circle.

The shapes are not likely to be seen dead on; they may be seen at an oblique angle.

Color is an interesting variable in the images, but it is not the primary focus of this exercise. The ability to use geometrical shapes is the point of this post.

The first such shape is Figure 1.

Copyright John R. Clarke.


The next shape is Figure 2. Do you see a lighted plane on the left partially obscured by an extruded rectangle, otherwise known as a rectangular prism or cuboid?



Figure 3. Yet another image, somewhat similar to Figure 2:



And a fourth image, Figure 4.

Copyright John R. Clarke.


Now, lets try some variations on the theme.


















The four images immediately above are identical to the first four images, but by seeing them in this order you may detect that there are only two unique images.

The images on the right are simply the images on the left rotated 180°; that is, they are turned upside down.

And yet most people identify an entirely different geometry, depending on which way the images are rotated.

So, seeing is believing …

… or is it?

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I do not know if this visual phenomenon has a name or not: I accidentally discovered it when looking at images to post on a laboratory wall. One figure looked unfamiliar; I was confused by it, until I happened to rotate it.

As the French say, voila. It was an optical illusion caused by our brain’s tendency to look for familiar shapes in unfamiliar and potentially confusing images.

There is a literature on the illusions of inverted images where images have been digitally manipulated (sometimes called the Thatcher Effect), but the images above have not been altered in any way.






How Will You Try to Kill Me?

Émile Jean-Horace Vernet-The Angel of Death

It’s been over three years since I posted a cautionary tale about oxygen sensors in rebreathers, and the calamities they can cause. Since then, the toll of divers lured to their death has been steadily mounting. In one week alone in April 2016, at almost the same geographical latitude in Northern Florida, there were two diving fatalities involving rebreathers. It is an alarming and continuing trend.

I know a highly experienced diver who starts each dive by looking at his diving equipment, his underwater life support system, and asking it that title question: How will you try to kill me today?

This deep cave diver, equally at home with open circuit scuba and electronic rebreathers, is not a bold cave diver. He is exceptionally cautious, because he is also the U.S. Navy’s diving accident investigator. He has promised me that his diving equipment will never end up in our accident equipment cage.

He and I have seen far too many of the diving follies where underwater life support systems fail their divers. But the crucible in which those fatal failures are often born are errors of commission or omission by the deceased.

Carelessness and an attitude of “it can’t happen to me” seem all too prevalent, even among the best trained divers. Divers are human, and humans make mistakes. Statistically, those accidents happen across all lines of experience: from novice divers, to experienced professional and governmental divers, and even military divers. They all make mistakes that can, and often do, prove fatal.

It is exceedingly rare that a life support system fails all by itself, since by design they are robust, and have either simple, fool-proof designs, or redundancy. In theory a single failure should not bring a diver to his end.
The “head”, triplicate oxygen sensors, oxygen solenoid and wiring leading to the rebreather CPU. Image from


Are oxygen sensors trying to kill you? That depends on how old they are? Are they in date? Ignoring the expiration date on chocolate chip cookies probably won’t kill you, but ignoring the expiration date on oxygen sensors may well prove fatal. Complex systems like rebreathers depend upon critical subsystems that cannot be neglected without placing the diver at risk.

Oxygen sensors are usually found in triplicate, but if one or more are going bad during a dive, the diver and the rebreather can receive false warnings of oxygen content in the gas being breathed.  We have seen a rebreather computer “black box” record two sensor failures, and it’s CPU logic deduced that the single working sensor was the one in error.

The controller’s programmed logic forced it to ignore the good sensor, and thus the controller continued to open the oxygen solenoid and add oxygen in an attempt to make the two dying sensors read an appropriately high O2. Eventually, the diver, ignoring or not understanding various alarms he was being given, went unconscious due to an oxygen-induced seizure. His oxygen level was too high, not too low.

Unlike fuel for a car or airplane, you can have too much oxygen.

Oxygen sensors do not fail high, but they do fail low, due to age. Rebreather manufacturers should add that fact into their decision logic tree before triggering inaccurate alarms. But ultimately, it’s the diver’s responsibility to examine his own oxygen sensor readings and figure out what is happening. The analytical capability of the human brain should far exceed the capability of the rebreather CPU, at least for the foreseeable future.

JAKSA high pressure 6-volt solenoid used in a Megalodon rebreather. NEDU photo.

Oxygen addition solenoids hold back the flow of oxygen from a rebreather oxygen bottle until a voltage pulse from the rebreather controller signals it to open momentarily. The oxygen flow path is normally kept closed by a spring inside the solenoid, holding a plunger down against its seat.

But solenoids can fail on occasion, which means they will not provide life giving oxygen to the diver. The diver must then either manually add oxygen using an addition valve, or switch to bailout gas appropriate for the depth.

Cut-away diagram of a 24-volt Jaksa 200 bar solenoid.

Through either accident or design, divers have been known to invert their solenoid spring and plunger, thereby keeping the gas flow open. In that case, oxygen could not be controlled except by manually turning on and off the valve to the oxygen tank. Of course, knowing when oxygen is too low or too high would depend upon readings from the oxygen sensors.

Suffice it to say that such action would be extremely reckless. And if the oxygen sensors were old, and thus reading lower than the true oxygen partial pressure, the diver would be setting himself up for a fatal oxygen seizure. It has happened.

Assuming a solenoid has not been tampered with, alarms should warn the diver that either the solenoid has failed, or that the partial pressure of oxygen is dropping below tolerance limits.

But as the following figures reveal, if the diver does not react quickly enough to add oxygen manually, or switch to bail out gas, they might not make it to the surface.

The three figures below are screen captures from U.S. Navy software written by this author, that models various types of underwater breathing apparatus, rebreathers and scuba. In the setup of the model, an electronically controlled, constant PO2 rebreather is selected. In the next screen various rebreather parameters are selected, and in this case we model a very small oxygen bottle, simulating an oxygen solenoid failure during a dive. On another screen, a 60 feet sea water for 60 minutes dive is planned, with the swimming diver’s average oxygen consumption rate set at 1.5 standard liters per minute.

Screen shot 3Screen shot 2










On the large screen shot below, we see a black line representing diver depth as a function of time (increasing from the dashed grey line marked 0, to 60 fsw), a gray band of diver mouth pressure, and an all-important blue line showing the partial pressure of inspired oxygen as it initially increases as the diver descends, then overshoots, and finally settles off at the predetermined control level of oxygen partial pressure (in this case 1.3 atmospheres). Broken lines on the very bottom of the graph show automated activation of diluent add valve, oxygen add solenoid, and over pressure relief valve. Long horizontal colored dashes show critical levels of oxygen partial pressure, normal oxygen level (cyan) and the limit of consciousness (red).

Screen shot 1
Screen shot of UBASim results after an ill-fated 60 fsw dive.

The oxygen solenoid fails 53.7 minutes into the dive, no longer adding oxygen. Therefore the diver’s inhaled oxygen level begins to drop. Rather than follow the emergency procedures, or perhaps being oblivious to the emergency, this simulated diver begins an ascent. As ambient pressure drops during the ascent, the drop in oxygen pressure increases.

In this particular example, 62.5 minutes after the dive began, and at a depth of 13.5 feet, the diver loses consciousness. With the loss of consciousness, the diver’s survival depends on many variables; whether he’s wearing a full face mask, whether he sinks or continues to ascend, or is rescued immediately by an attentive boat crew or buddy diver. It’s a crap shoot.

So basically, the rebreather tried to kill the diver, but he would only die if he ignored repeated warnings and neglected emergency procedures.

What about your rebreather’s carbon dioxide scrubber canister? Do you know what the canister duration will be in cold water at high work rates? Do you really know, or are you and the manufacturer guessing? What about the effect of depth, or helium or trimix gas mixes? Where is the data upon which you are betting your life, and how was it acquired?

Scrubber canister and sodalime. NEDU Photo

NEDU photo.












Sadly, few rebreathers have dependable and well calibrated carbon dioxide sensors; which is unfortunate because a depleted or “broken through” scrubber canister can kill you just as dead as a lack of oxygen. The only difference is a matter of speed; carbon dioxide will knock you out relatively slowly, compared to a lack of oxygen.

But if you think coming up from a dive with a headache is normal, then maybe you should rethink that. It could be that your rebreather is trying to kill you.





In the Claws of a Monster

By Huhu Uet (Own work) [CC BY-SA 3.0 (], via Wikimedia Commons
By Huhu Uet via Wikimedia Commons
Nature does not always provide good options. When faced with weather-related adversity, making the right decision can be as much a matter of luck as wisdom.

Homerville, Georgia is the home of some first-rate southern barbeque and home of one of the best genealogical libraries in the Southeast, the Huxford Geneological library. In June of 1975 I made an unintended stop at the Homerville Airport after flying my 1962 Cessna 150 from Thomasville, Georgia to Waycross, Georgia. My wife and Mother-In-Law were in Waycross, visiting, and on a Friday afternoon I took off in my 2-seater aircraft to meet my wife’s family 92 miles away.

As I approached Waycross a thunderstorm was directly on top of the field. The Waycross Fixed Base Operator confirmed they were being clobbered, so I made a 180 degree turn and flew 26 miles back to the Homerville airport that I had passed on the way in.

When I landed I found I was the only aircraft, and only human, on the field. But regrettably, there were no tie-downs, ropes or chains that I could use to secure the little Cessna while I found a phone to call my wife and tell her about the change in plans. The weather was good, and it should take only a few minutes to bother one of the nearby neighbors for a phone call. What could go wrong?

After I explained to my family where I was, I thanked the friendly lady who let me use her phone, and headed back to my aircraft. But as I approached the plane, the view at the other end of the runway was turning ugly. Another thunderstorm was headed straight for the field. And it was close, and mean-looking.

I climbed into the cockpit, started the engine, and sat there assessing what I was seeing out the windscreen. And thinking about options.

What I wanted to do was take-off and head for Waycross. I was not at all prepared to abandon my airplane and watch it be destroyed by the approaching storm. As I considered the fact that I would be taking off towards a thunderstorm, I thought of riding out the gusts on the ground, using the engine power and rudder to keep the plane pointed into the wind. But as I throttled the engine and rudder back and forth, reacting to the increasing gusts, I realized the 1000 pound plane would inevitably be picked up, with me in it, and dashed to the ground. It would not be a pretty sight, especially if it was lifted to a significant height by updrafts before being dropped.

The wind ahead of the thunderstorm rain shaft was picking up, gusting, and as I weighed the different options, the storm kept getting closer, closing my window of opportunity. As they say, the clock was ticking.

Finally, I decided I’d rather be airborne, in some semblance of control, than being airborne out of control. The storm was not yet on the field, but I knew I had scant seconds before the cloudy violence would make an escape impossible. I pressed hard on the brakes, dropped my flaps one notch, pushed the throttle full in, and when the engine was roaring as loudly as a 100 horse power engine can roar, I let go of the brakes and started my takeoff roll.

Thanks to the advantage of straight-down-the-runway storm winds, I lifted off very quickly. I stomped a rudder pedal and dipped a wing to turn as fast as I could away from the storm, passing over the roofs of nearby houses much closer than the residents were used to, I’m sure. But the plane was fully in control and headed quickly towards safety.

Although the storm winds were actually helping to push me away, I felt an occasional shudder from the back of the plane. I imagined the storm shaking me in its jowls, plucking at my wings with its sharp talons, as if angry that I had escaped its clutches.

I made it safely to Waycross, but my aircraft’s escape was short-lived.

If there were such a thing as a Storm Monster, I would think that it was malevolent, because exactly two weeks after that incident another thunderstorm hit the field in Waycross, where the plane was supposedly safely chained down. I was on the field as a vengeful storm snapped the steel chains holding down my plane’s tail, flipping the plane over on its back, crushing the tail. My little bird never had a chance.

I had risked my life in Homerville to avoid watching my beautiful bird be destroyed, only to see it destroyed in the same manner only a fortnight later.

We tell our children there are no monsters … but I’m not so sure.


Where Things Move Quickly and Darkly

I came across a great article from the New Yorker with an interesting title. In fact, my interest lasted all the way to the end.

Spooked: What do we learn about science from a controversy in physics?

“Albert Einstein (Nobel)” by Unknown – Official 1921 Nobel Prize in Physics photograph. Licensed under Public Domain via Wikimedia Commons

If you get the feeling that science is not as pure of thought and logic as it pretends to be, then you will find some comfort in Adam Gopnik’s approachable review of the deeply hidden controversy surrounding what Albert Einstein called “spooky action at a distance.” Spooky action is the weirdest of all science, and makes telepathy and clairvoyance seem almost banal by comparison.

In my opinion, parts of Gopnik’s none-too-technical article remind me of the quote by Dr. Jason Parker, the protagonist in the science fiction thriller, “Middle Waters“. In a supposed speech to the open-minded Emerald Path Society, Parker said, “There are regions between heaven and Earth where magic seems real and reality blurs with the surreal. It is a place where things move quickly and darkly, be they friend or foe. The hard part for me is knowing the difference between them.”

Gopnik expressed that thought more prosaically by the following: “”Magical” explanations, like spooky action, are constantly being revived and rebuffed, until, at last, they are reinterpreted and accepted. Instead of a neat line between science and magic, then, we see a jumpy, shifting boundary that keeps getting redrawn.”

Gopnik goes on to say, “Real-world demarcations between science and magic … are … made on the move and as much a trap as a teaching aid.”

To be honest, I did leave out Gopnik’s entertaining reference to Bugs Bunny and Yosemite Sam. Again, if you have ever been suspicious of the purity of science, the New Yorker article is well worth the read.

Unlike the concerns of Einstein, Neils Bohr and the rest of the cast of early 20th century physicists, the anxiety of Jason Parker, the fictional hero, is not cosmological; it’s personal. It’s every bit as personal as it is for each of us when we sometimes question our sanity.

Yes, real life can be like that sometimes, when things intrude into our ordered lives, as quickly as a Midwest tornado, but with less fanfare and warning. But every bit as destructive. And it is at those points, those juxtapositions with things radical, unexpected, that we end up questioning our grip on reality.

After all, what could be more unexpected and unreal seeming than the notion that cosmological matter we can’t see, dark matter, could send comets crashing into the Earth, as Gopnik mentioned, and the  Harvard theoretical physicist Lisa Randall wrote about in her book Dark Matter and the Dinosaurs.

So, Jason Parker had every reason to be wary of things that move quickly and darkly. They can be a killer.

Sometimes, as in the case of Parker, those internal reflections do end up having a cosmological consequence. But even if they don’t, it’s a good idea to occasionally reexamine our lives for the things which may seem one day to be magical, and the next day to be very real.

In short, the magic should not be dismissed out of hand, because, after all, just like “spooky action at a distance” and “dark matter”, it may not be magic after all.



Remote Viewing – Stretching the Limits of Science in Fiction

Laser physicist Harold E. Puthoff.

I once met the Father of the U.S Remote Viewing program, unawares.

A decade ago, at the request of a Navy engineer who ended up being a character in my novel Middle Waters, I invited Dr. Harold E. Puthoff into the Navy Experimental Diving Unit to give a talk on advanced physics. He had attracted a small but highly educated and attentive crowd which, like me, had no idea that the speaker had once led the CIA in the development of its top secret Remote Viewing program.

Of late, Puthoff’s energies have been directed towards the theoretical “engineering of space time” to provide space propulsion, a warp drive if you will. Although strange by conventional physics standards, similar avant-garde notions are receiving traction in innovative space propulsion engines such as NASA’s EMdrive.

Puthoff is the Director of the Institute of Advanced Studies at Austin, in Texas, but before that, and more germane to this discussion, Puthoff was a laser physicist at the Stanford Research Institute. It was there that the CIA chose him to lead a newly created Remote Viewing program, designed to enable the U.S. to maintain some degree of competiveness with Russia’s cold war psychic spying program.

6800 feet down in the Desoto Canyon

Psychic spying was purportedly the method used by the two superpowers to visualize things from a distance; not from a satellite, but from what some call the highly developed powers of the mind’s eye. If we believe what we read on the subject, Remote Viewing was eventually dropped from the US psychic arsenal not because it had no successes, but because it was not as reliable as signal intelligence (SIGINT), satellite imagery, and spies on the ground. But, it has been argued, it might be ideal in locations where you can’t put spies on the ground, such as the dark side of the moon, or the deep sea .

Serendipitously, as I started writing this blog post, Newsweek published a review of the Remote Viewing efforts of Puthoff and others in a November 2015 issue. The article seemed fairly inclusive, at least more so than other articles on Remote Viewing I’ve seen, but the Newsweek author was not particularly charitable towards Puthoff. Strangely, the strength and veracity of Puthoff’s science was reportedly criticized by two New Zealand psychologists who, as the Newsweek author quoted, had a “premonition” about Puthoff.

“Psychologists” and “premonitions” are not words commonly heard in the assessment of science conducted by laser physicists, especially those employed by the CIA. The CIA is not stupid, and neither are laser physicists from Stanford.

To the extent that I am able to judge a man by meeting him in person and hearing him talk about physics, I would have to agree with Puthoff’s decision to ignore his ill-trained detractors. Every scientist I know has had detractors, and as often as not those detractors have lesser credentials. Nevertheless, I have the good sense to not debate the efficacy of remote viewing. I don’t know enough about it to hold an informed opinion. However, there seems to be some evidence that it worked occasionally, and for a science fiction writer that is all that is needed.

Nuclear physicist Enrico Fermi.

As my curiosity became piqued by the discovery of the true identity of my guest speaker at NEDU, and as I learned what he had done for the U.S. during the Cold War, I thought of another great physicist, Enrico Fermi, one of the fathers of the atomic bomb. In the midst of a luncheon conversation with Edward Teller, Fermi once famously asked, “Where are they?” The “they” he was referring to, were extraterrestrial aliens.

What became known as Fermi’s Paradox went something like this: with all the billions of stars with planets in our galactic neighborhood, statistically there should be alien civilizations everywhere. But we don’t see them. Why not? “Where are they?”

In most scientists’ opinions, it would be absurdly arrogant for us to believe we are the only intelligent life form in the entire universe. And so ETs must be out there, somewhere. And if there, perhaps here, on our planet, at least occasionally. And that is all the premise you need for a realistic, contemporary science fiction thriller.

But then there is that pesky Fermi Paradox. Why don’t we see them?

Well, they could indeed be here, checking us out by remote viewing, all the while remaining safely hidden from sight. After all, as one highly intelligent Frog once said, humans are a “dangerous species” fictionally speaking of course.

That “hidden alien” scenario may be improbable, but it’s plausible, if you first suspend a little disbelief. If we can gather intelligence while hiding, then certainly they can, assuming they are more advanced than humans. A technological and mental advantage seems likely if they are space travelers, which they almost have to be within the science fiction genre. Arguably, fictional ETs may have long ago engineered space-time, which could prove mighty convenient for tooling around the galactic neighborhood.

So, if in the development of a fictional story we assume that ETs can remote view, the next question would be, why? Is mankind really that dangerous?

Well, I don’t intend for this post to be a spoiler for Middle Waters, but I will say that the reasons revealed in the novel for why ETs might want to remote view, are not based on fear of humans, but are based on sound science. From that science, combined with a chance meeting with Hal Puthoff, the basic premise of a science fiction thriller was born.

So, to correct what some of my readers have thought, I did not invent the concept of “remote viewing”. It is not fictional; it is real, and was invented and used by far smarter people than myself, or even that clever protagonist, Jason Parker.



Eating Crow – Safe Water Temperatures for Scuba Regulators

CrowScientists and engineers love to argue, and unlike the case with politicians, compromise is not an option. Technologists speak for nature, for the truth of a universe which does not speak for itself. But when a technologist is wrong, they usually have to eat some crow, so to speak.

Stephen Hawkings, the famous cosmologist, freely admits his brilliant doctoral dissertation was wrong. Crow was eaten, and Hawkings moved on to a better, arguably more correct view of the universe.

Now, on a much less grand scale, this is my time for eating crow.

There has been quiet disagreement over the water temperature above which a scuba regulator is safe from free-flowing or icing up. Those untoward icing events either give the diver too much gas, or not enough. Neither event is good.

Based upon an apocryphal Canadian government study that I can’t seem to put my hands on anymore (government studies are rarely openly available), it has long been believed by the Canadians and Americans that in water temperatures of 38°F or above, regulator icing problems are unlikely. That temperature was selected because when testing older, low flow Canadian regulators, temperatures inside the regulator rarely dropped below 32°F when water temperature was 38°F.

Regulator ice
U.S. Navy photo.

As shown in an earlier blog post, in 42°F water and at high scuba bottle pressures (2500 psi) in instrumented second stage regulators (Sherwood Maximus) second stage internal temperature dropped below zero Celsius (32°F) during inspiration. During exhalation the temperature rose much higher, and the average measured temperature was above freezing. Nevertheless, that regulator free flowed at 40 minutes due to ice accumulation.

Presumably, a completely “safe” water temperature would have to be warmer than 42°F. But how much warmer?

My European colleagues have stated for a while that cold water regulator problems were possible at any temperature below 10°C, or 50°F. However, as far as I can tell that assertion was not based on experimental data. So as we began to search for the dividing line between safe and unsafe water temperatures in another brand of regulator, I assumed we’d find a safe temperature cooler than 50°F. For that analysis, we used a generic Brand X regulator.

To make a long story short, I was wrong.

To understand our analysis, you must first realize that scuba regulator freeze-up is a probabilistic event.  It cannot be predicted with certainty. Risk factors for an icing event are diving depth, scuba bottle pressure, ventilation (flow) rate, regulator design, and time. In engineering terms, mass and heat transfer flow rates, time and chance determine the outcome of a dive in cold water.

At NEDU, a regulator is tested at maximum anticipated depth and ventilated at a high flow rate (62.5 L/min) for a total period of 30 min. If the regulator free flows or stops flowing, an event is recorded and the time of the event is noted. Admittedly, the NEDU test is extremely rigorous, but it’s been used to select safe regulators for U.S. military use for years.

Tests were conducted at 38, 42, 45 and 50°F.

Next, an ordinal ranking of the performance for each regulator configuration and temperature combination was possible using an NEDU-defined probability-of-failure test statistic (Pf). This test statistic combines the number of tests of a specific configuration and temperature conducted and the elapsed time before freezing events occurred. Ordinal ranks were calculated using equation 1, Eqnwhere n is the number of dives conducted, E is a binary event defined as 0 if there is no freezing event and 1 if a freezing event occurs, t is the elapsed time to the freezing event from the start of the test (minutes), and k is an empirically determined constant equal to 0.3 and determined to provide reasonable probabilities, i is the index of summation.

Conshelf XIV pic 2
Click for a larger image.

Each data point in the graph to the left represents the average result from 5 regulators, with each test of 30-min or more duration. For conditions where no freezing events were observed at 30 min, additional dives were made for a 60-min duration.

As depicted, 40-regulator tests were completed, using 20 tests of the five primary second stages and 20 octopus or “secondary” second stages. Regression lines were computed for each data set. Interestingly, those lines proved to be parallel.

A second stage of a typical scuba regulator. The bite block is in the diver’s mouth.

The “octopus” second stage regulator (the part going in a scuba diver’s mouth) differed from the primary only by the spring tension holding the regulator’s poppet valve shut. More negative mouth pressure is required to pull the valve open to get air than in the primary regulator.

The test statistic does not provide the probability that a given test article or regulator configuration will experience a freezing event at a given temperature. However, it does provide the ability to rank the freezing event performance of regulator configurations at various temperatures.

Our testing reveals that in spite of my predictions to the contrary, for the Brand X regulator our best estimate of a “safe” water temperature, defined as Pf = 0, is roughly 53°F for the standard or “primary” second stage regulator and 49° F for the octopus or secondary regulator.

For all practical purposes, the European convention of 50°F (10°C) is close enough.

Eating crow is not so bad. Some think it tastes a little like chicken.

Separator smallEquation 1 came from J.R. Clarke and M. Rainone, Evaluation of Sherwood Scuba Regulators for use in Cold Water, NEDU Technical Report 9-95, July 1995.

Diving a Rebreather in Frigid Water: Canister Concerns


As evidenced by Under the Pole diving expeditions, rebreathers are being used in some of the most isolated and frigid places in the world. Some of those dive missions are surprisingly deep (111 meters, 330 feet) and long, about 2 hours.

That gives me cause for pause.

I suspect most divers are aware of the 1/3 rule for gas consumption on an open circuit (scuba) cave dive. You should use no more than 1/3 of your air supply on the way in, leaving you with 1/3 for the trip out, and 1/3 of your gas supply available in reserve. Sadly, even that amount of reserve has not saved all cave divers.

Now that cave divers are using rebreathers, the rules, at least for some, have changed. Some savvy rebreather cave divers use the rule of doubles: Always have twice as much oxygen, twice as much diluent, and twice as much canister as you think you’ll need. That plus an open-circuit or semi-closed circuit bailout should keep you safe — in theory.

Gas supply is easy to measure throughout a dive; there is a pressure gauge for all gases. But what about canister duration? Most divers assume they will have more canister duration available than gas supply; which means they don’t need to worry about canister duration. That would be a good thing, if it were true. After all, how many manufacturers provide expected canister durations for various work rates and water temperatures? Maybe, none? Or certainly very few.

I would be very surprised if manufacturers could say with certainty that during a two hour dive in -2°C (28°F) water, at depths to 111 meters that the scrubber can provide double the duration needed. That would be four hours in -2°C water, at all potential diver work rates.

Some of you may say, “Under-the-ice-diving is not like cave diving, so the doubles rule is too conservative.” I invite you to think again. Under polar ice, is there ready access to the surface? Not unless you’re diving directly under the through-ice bore hole the entire time.

In the U.S. Navy experience, obtaining useful data on canister durations from manufacturers is difficult. Duration data as a function of temperature is practically nonexistent. Therefore I will share the following information gleamed from scrubber canister testing in extreme environments by the Navy. While this blogger cannot reveal canister durations for military rebreathers, the information on the coefficient of varation (COV) is not protected. (There is no way to figure out what a canister duration is based solely on the COV.)

The following 4-minute video gives a good introduction to the coefficient of variation.

All rebreather divers should know that canister performance declines in an accelerating manner as water temperature drops between 50°F and 28°F. But what your rebreather manufacturer may not know is that the innate variability of canister durations also increases as water temperature drops. The Navy has found that trend in all types of rebreathers.

So, while canister durations drop considerably in cold water, you’re also less certain about what your canister’s endurance is going to be, because of the increase in duration variability. When canister duration drops and variability increases, a diver’s margin of safety becomes a gamble. Personally, I don’t like to gamble under water.

Coefficient of variation (COV, mean duration divided by the standard deviation) of a typical rebreather. Each data point is the mean of five canisters (n=5).

In the U.S. Navy, published canister durations take into account mean canister performance, and variability. That is accomplished through the use of 95% prediction intervals. The greater the variability in canister duration, the lower the published duration.

This method of determining safe canister durations has been in use by the U.S. Navy since 1999. However, I do not know if manufacturers use similar statistically-based methods for publishing canister durations. If they or you do not take duration variability into account as you dive cold, you may be in for a shock. Due to the nature of statistics, you may have 9 deep, cold dives with no CO2 problems, but find yourself in bad shape on the 10th dive.

If you did have a CO2 problem, it wouldn’t necessarily be anyone’s fault: it could just be a result of canister variability in action.

So, diver beware. Give yourself plenty of leeway in planning rebreather dives in frigid waters. After all, you do not want to become a statistic, caused ironically by statistics.

Separator small

If you have an interest in understanding the derivation of the prediction interval equation and its application, two videos of lectures by Dr. Simcha Pollack from St. John’s University may be helpful. Part I is found here, and Part 2 is found here.

Thanks to Gene Hobbs and the Rubicon Foundation, NEDU’s original report on the use of prediction limits to establish published canister durations is found here.

Burn My New State Flag – I Don’t Care


I’ve decided to invent a new series of non-controversial flags for all 50 states of the United States of America.

I began with a plain white flag. Not much to be controversial about there. (By the way, I was not the first to think of that.)

Then I proposed adding to each state flag the two letter state identifier used for our postal system. We’ve been using those for decades, so again, no controversy.

For instance, the Florida flag would be white with FL in the middle of it. If the state is really proud of itself, it could be a big, bold FL. If they’re a little embarrassed by, oh I don’t know, crime rates, hate crimes, voter apathy, or whatever, they could use smaller letters, and maybe not bolded. The voters could decide.

But voters would not get a choice on the overall design. Two white letters on a pure white background – that is the state flag formula.

Of course I tried this idea out on a focus group made up of mixed gender identity, mixed ethnic, educational level, and mixed financial levels. I even took care to keep the test group evenly divided among political parties.

And that’s when the trouble began.

Unfortunately there were many, many complaints, but I’ll only mention some of the more interesting ones; all based oddly enough on the Periodic Table of the Elements.

Take my state of Florida or example. FL stands for Florida of course, but the “F” in it represents the element Fluorine, a chemical which I believe has strengthened my teeth since childhood. But some believe it is a toxic chemical dumped into our water supply by all levels of government, (county, city, state and federal) to poison Americans. [Google it. I will not provide a link to those websites.] I’m highly skeptical of that notion, but I wouldn’t want to offend them by forcing them to look at “Fl”uorine on their flag.

And then there’s Florida’s neighboring state, Alabama. AL can stand for Alabama, but it also is the symbol for aluminum. Aluminum is cheap and not very strong. Some Alabamians don’t like that word association, even though it’s been on their U.S. mail since 1963.

AR for Arkansas also means Argon, a narcotic gas. Some didn’t want to be associated with stoners.

GA for Georgia is also gallium. Gallium melts at approximately body temperature, which was too troublesome of an association for those who are still pained by Sherman’s March to the Sea through Georgia. A melting-in-the heat mineral connotes weakness, which Georgians certainly don’t want their flag suggesting.

The most memorable scene in "Gone With the Wind" was the recreation of Confederate Gen. John B. Hood's destruction of his own munitions train. The scene was filmed on a studio lot in Los Angeles in December 1938.
A frame from “Gone With the Wind” published at

CA for California, also stands for calcium, a component of lime, which is basically crushed limestone. Water and carbon dioxide react to form acidic water that dissolves limestone. With an atmospheric carbon dioxide rise and global warming, some apparently fear that acid rain will dissolve their state, leaving nothing but caverns leading straight to geological fault lines. Even though I don’t think there’s an awful lot of  limestone in California (certainly not like Florida), some just don’t concern themselves with the facts. Apparently, for them this fear is too horrendous to contemplate, so CA is out as far as a state flag goes.

MT stands for Montana, or Meitnerium. I must admit I wouldn’t have thought of that one, but apparently some apologist did. I was quite surprised to find out that Meitnerium was created by Germans after a week of bombardment of bismuth with iron. The notion of Germans bombarding anything with iron for a week was simply too painful for those who had survived the Nazi bombardment of Russia and Poland. Apparently some take the analogy very seriously. The MT flag had to go.

Louisiana, or LA, is also Lanthanum, which in Greek means “escapes notice”. It is soft enough to be cut with a knife. It was reported that students from the LSU Chemistry Department strongly objected to being compared to a soft, highly reactive, and hardly noticed element. I guess I can see their point.

PA or “Protactinium” sounded like an interesting element synonymous with Pennsylvania. That is until someone pointed out the following from the Los Alamos Periodic Table of the Elements. “Because of its scarcity, high radioactivity and high toxicity, there are currently no practical uses for protactinium other than that of basic scientific research, and for this purpose, protactinium is generally extracted from spent nuclear fuel.” OK, I get it. There is basically nothing in that sentence that would be a point of pride for Pennsylvanians.

Why does this have to be so hard?

Not far away geographically or chemically from PA is MD, or Mendelevium. That element is named after Dmitri Mendeleev, a Russian Chemist who apparently invented the (or maybe “a”) Periodic Table. He is certainly a noteworthy man to help us remember the state of Maryland (MD), but ever since Vladimir Putin went on the offense in Eastern Europe, no state wants to be associated with anything Russian. I can understand that.

Then there is Indiana, or Indium. Now who could find anything to complain about either Indiana or Indium? Well, lo and behold, someone read that Indium gives out a high-pitched “cry” when bent, somewhat like a little girl I suppose. That20140530_125613 discovery immediately condemned it as being sexist, mocking our youngest young ladies.

Really? This is getting ridiculous.

There were a few flags that were not deemed objectionable by anyone. For example, MN stands for Minnesota, or Manganese, as in deep-sea manganese nodules. No one objected to MN, so Minnesota, I guess your flag stands. The same went for SC, South Carolina, or Scandium; no objection. Then there was CO for Colorado, or Cobalt, and MO for Missouri or Molybdenum.

Ironically, people have been writing these state initials on their stationary for years and no one objected. However place the same initials on a state flag and someone gets offended; which is a fact that puzzles me. You see no one salutes a state flag. No one pledges allegiance to it. It has no power, no meaning. If you don’t like my flag, make up your own!

To be fair and all-inclusive, I thought about alternative flag designs that might appease everyone. Suppose we just number the states in the order in which they entered the union (ratified the Constitution). The first four would be Delaware, Pennsylvania, New Jersey and Georgia. But of course some highly competitive New Yorkers might be miffed that Georgia, a Southern State, entered the Union before New York did. And we can’t have any New Yorkers miffed.

So then I considered a random number generator. Your state might be State 87.42 and the adjoining state might be 91.82. That was a fine idea until I considered that the same problematic scientists who fussed over their concerns with a Periodic Table of the States would question how truly random was the random number generator.

It exhausts me to think of the possibilities.

So, if I was King for a Day I would simply say this is how it will be: All states will have white flags with two letter state identifiers. If someone doesn’t like it, then burn it, deface it, walk on it; I don’t care. It has no meaning except to let people know what state they’re in. And if that’s a problem, if people really don’t know what state they’re in, then using my powers as King for a Day I’d give everyone a free GPS.

Now, does that make everyone happy?


A Novel – A Song Just Waiting to Bust Out

SAM_0557One of the most memorable quotes I’ve heard from a child came from his experience listening to classical music. I don’t remember who said it (Google comes up empty-handed), but I’ve never forgotten it.

“A symphony is music with a song waiting to bust out any minute.”

Those words were the child’s response to listening to a symphonic piece. The little listener kept expecting to hear a song, but no sooner did the musicians seem to be closing in on a melody, than the music changed and darted off down another musical path. I suspect that was a little frustrating to the kid; but at least it kept him listening, expectantly.

Being a musician, I can fully appreciate the correctness of his innocent comment.

Classical music is technical; in fact, highly so. Orchestration is a wonderment to those of us who aren’t both talented and trained in the art. The printed lines for a solo instrument, like the clarinet I file0001662840435play, are defined by strict mathematical relationships between frequencies of sound. If the math is not precise, then the sound will not be precise and melodic. That is to say, the sound will not be music, but rather noise.

I consider myself a technical person. As a scientist, I understand the technical rigor and precision which is required for composing and orchestration, but also for scientific and engineering calculations and publications. Indeed, I’ve spent decades writing technical papers, many with a fair amount of mathematical basis. I kept the creative, the musical side, bottled up, because it’s not publishable. Technical publications are, well, technical. They are neither pretty nor tuneful.

But as I mingle vicariously with other technical writers, I find that some of them also have a pent-up desire for creative writing. With a somewhat guilty feeling, they have actually penned very good, non-technical prose. And even a few poems.

Now that I, a scientist, have released my first novel, Middle Waters, hugely imaginative compared to my day-to-day paid technical writing, I feel I have birthed a bastard child.

Oh, but how I love that child.

Now let the song begin…


Authorized for Cold Water Service: What Divers Should Know About Extreme Cold

The following is reprinted from my article published in ECO Magazine, March 2015.  It was published in its current format as an ECO Editorial Focus by TSC Media. Thank-you Mr. Greg Leatherman for making it available for reprinting.ECO Magazine

It is the highpoint of your career as an environmentally minded marine biologist. The National Science Foundation has provided a generous grant for your photographic mission to the waters 100 ft below the Ross Ice Shelf, Antarctica. Now you’re on an important mission, searching for biological markers of climate change.

Under Antarctic Ice, photo by Dr. Martin Sayer.

Above you lies nothing but a seemingly endless ceiling of impenetrable ice, 10 ft thick. Having spent the last several minutes concentrating on your photography, you look up and notice you’ve strayed further from safety than you’d wanted. The strobe light marking the hole drilled in the ice where you’ll exit the freezing water is a long swim away. And, unfortunately, your fellow scientist “buddy” diver has slipped off somewhere behind you, intent on her own research needs.

You’re diving SCUBA with two independent SCUBA regulators, but in the frigid cold of the literally icy waters, you know that ice could be accumulating within the regulator in your mouth. At the same time, a small tornado of sub-zero air expands chaotically within the high-pressure regulator attached to the single SCUBA bottle on your back—and that icy torrent is increasingly sucking the safety margins right out of your regulator. You are powerless to realize this danger or to do anything about it.

At any moment, your regulator could suddenly and unexpectedly free flow, tumultuously dumping the precious and highly limited supply of gas contained in the aluminum pressure cylinder on your back. You’re equipped and trained in the emergency procedure of shutting off the offending regulator and switching to your backup regulator, but this could also fail. It’s happened before. 

As you try to determine your buddy’s position, you’re feeling very lonely. You realize the high point of your career could rapidly become the low point of your career—and an end to your very being. Picture046

The preceding is not merely a writer’s dramatization. It is real, and the situation could prove deadly—as it has in far less interesting and auspicious locations. Regulator free flow and limited gas supplies famously claimed three professional divers’ lives in one location within a span of one month.

There is a risk to diving in extreme environments. However, the U.S. Navy has found that the risk is poorly understood, even by themselves—the professionals. If you check the Internet SCUBA boards, you constantly come across divers asking for opinions about cold-watersafe regulators. Undoubtedly, recent fatalities have made amateur divers a little nervous—and for good reason.

Internet bulletin boards are not the place to get accurate information about life support safety in frigid water. Unfortunately, the Navy found that manufacturers are also an unreliable source. Of course, the manufacturers want to be fully informed and to protect their customers, but the fact remains that manufacturers test to a European cold-water standard, EN 250. By passing those tests, manufacturers receive a “CE” stamp that is pressed into the hard metal of the regulator. That stamp means the regulator has received European approval for coldwater service.

As a number of manufacturers have expensively learned, passing the EN 250 testing standard is not the same as passing the more rigorous U.S. Navy standard, which was recently revised, making it even more rigorous by using higher gas supply pressures and testing in fresh as well as salt water. Freshwater diving in the Navy is rare—but depending on the brand and model of regulator in use, it can prove lethal.

The unadorned truth is that the large majority of manufacturers do not know how to make a consistently good Performing cold-water regulator. Perhaps the reason is because the type of equipment required to test to the U.S. Navy standard is very expensive and has, not to date, been legislated. Simply, it is not a requirement.

Some manufacturers are their own worst enemy; they cannot resist tinkering with even their most successful and rugged products. This writer is speculating here, but the constant manufacturing changes appear to be driven by either market pressures (bringing out something “new” to the trade show floor) or due to manufacturing economy (i.e., cost savings). The situation is so bad that even regulators that once passed U.S. Navy scrutiny are in some cases being changed almost as soon as they reach the “Authorized for Military Use” list. The military is struggling to keep up with the constant flux in the market place, which puts the civilian diver in a very difficult position. How can they—or you—know what gear to take on an environmentally extreme dive?

My advice to my family, almost all of whom are divers, is to watch what the Navy is putting on their authorized for cold-water service list. The regulators that show up on that list (and they are small in number) have passed the most rigorous testing in the world.

Through hundreds of hours of testing, in the most extreme conditions possible, the Navy has learned what all SCUBA divers should know:

• Even the coldest water (28°F; -2°C) is warm compared to the temperature of expanding air coming from a first stage regulator to the diver. There is a law of physics that says when compressed air contained in a SCUBA bottle is expanded by reducing it to a lower pressure, air temperature drops considerably. It’s the thermal consequence of adiabatic (rapid) expansion.

• Gas expansion does not have to be adiabatic. Isothermal (no temperature change) expansion is a process where the expansion is slow enough and heat entry into the gas from an outside source is fast enough that the expanded gas temperature does not drop.

• The best regulators are designed to take advantage of the heat available in ice water. The most critical place for that to happen is in the first stage where the greatest pressure drop occurs (from say 3,000 psi or higher to 135 psi above ambient water pressure (i.e., depth). They do that by maximizing heat transfer into the internals of the regulator.

• First stage regulators fail in two ways. The most common is that the first stage (which controls the largest pressure drop) begins to lose control of the pressure being supplied to the second stage regulator, the part that goes into a diver’s mouth. As that pressure climbs, the second stage eventually can’t hold it back any longer and a free flow ensues.

• The second failure mode is rare, but extremely problematic. Gas flow may stop suddenly and completely, so that backup regulator had better be handy.

• Second stage regulators are the most likely SCUBA components to fail in cold water due to internal ice accumulation.

• Free flows may start with a trickle, slowly accelerating to a torrent, or the regulator may instantly and unexpectedly erupt like a geyser of air. Once the uncontrolled, and often unstoppable free flow starts, it is self-perpetuating and can dump an entire cylinder of air within a few minutes through the second stage regulator.

• A warm-water regulator free flow is typically breathable; getting the air you need to ascend or to correct the problem is not difficult. In a cold-water-induced free flow, the geyser may be so cold as to make you feel like you’re breathing liquid nitrogen and so forceful as to be a safety concern. Staying relaxed under those conditions is difficult, but necessary.

• Water in non-polar regions can easily range between and 34°F to 38°F; at those temperatures, gas entering the second stage regulator can be at sub-freezing temperatures. European standard organizations classify ~10°C (50°F) as the cold/non-cold boundary. The Navy has found in the modern, high-flow regulators tested to date that 42°F is the water temperature where second stage inlet temperature is unlikely to dip below freezing.

• The small heat exchangers most manufacturers place just upstream of the second stage is ineffective In extreme conditions. They quickly ice over, insulating that portion of the regulator from the relative warmth of the surrounding water. Heat Ex Regulator

• Regulator “bells and whistles” are an unknown and can be problematic. Second stage regulators with multiple adjustments can do unpredictable things to heat transfer as the diver manipulates his controls. The last thing a cold-water diver should want is to make it easier to get more gas. High gas flows mean higher temperature drops and greater risk of free flow.

• Only manufacturer-certified technicians should touch your regulator if you’re going into risky waters. The technician at your local dive shop may or may not have current and valid technician training on your particular life support system. Don’t bet your life on it— ask to see the paperwork.

• Follow Navy and Smithsonian* guidance on handling and rinsing procedures for regulators in frigid waters. A single breath taken above the surface could freeze a regulator before you get your first breath underwater.

U. S. Navy reports on tested regulators are restricted. However, the list of those regulators passing all phases of Navy testing is available online. If your regulator, in the exact model as tested, is not on that list, do yourself a favor and don’t dive in frigid waters.


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The original Editorial Focus article is found in the digital version of the March ECO magazine here, on pages 20-25.


I Remember Nothing After the First Bounce
From an album belonging to barnstormer Sergeant Carter G. Buton. Photo from latter half of the 1920s. Image found at San Diego Air & Space Museum Blog.

“It was a gorgeous day to jump from a perfectly good airplane. I, Mickey McGurn, was good at it, and I got paid well to do it.

But one day I got careless.

It was 1927, and parachute jumping was a new thing on the barnstorming circuit. It made people catch their breath when I jumped out of airplanes. They just knew they were going to see me fall straight to my death.

I would gather the parachute in my arms, without packing it, bundle it into the cockpit, and go aloft for a jump.

One day a number of my barnstorming friends protested at the way I handled the parachute. But I told them to mind their own business.

“Forget it,” I said. “I built this thing myself and I know what it’ll do.”

Well, I might have been wrong about that, because one day the ‘chute didn’t work. It opened only about a quarter of the way and I fell to the ground with a terrific speed. Those folks who were waiting to see me die almost got more than they bargained for.

Folks told me I bounced at least 10 feet into the air, but I don’t remember anything after I hit the ground.

The doctors said I broke pretty much every bone in my body, but obviously I lived, sort of.

I’m now hobbling around on crutches. I’m deaf, nearly blind, and can’t taste my food, or enjoy any of the things I used to.

My bones have healed, sort of, but not the way they were when I was a cocky young fool who felt invincible.

I guess I should have listened to my friends. They realized I was courting disaster, but I was too proud, or arrogant, or just plain stupid to notice it.

But they were right.

I suppose that no matter what you do, whether it’s racing cars, jumping out of airplanes, or walking on the bottom of the ocean, your friends are usually better at telling when you’re getting careless than you are.

I guess it’s similar to the way a friend can usually tell when you’re drunk before you can.


The above is a fictional version of an actual accounting by one aviation daredevil named Mickey McGurn, given to a newspaper reporter for the Syracuse American. The short piece appeared in the Sunday edition under a section called the “World of Aviation”. The publication date was February 26, 1928. The writer was Gordon K. Hood, a feature writer who penned several aviation-themed chapters for the paper, a collection of mini-stories such as this one, collectively called “Sprouting Wings”. Mr. Hood was himself quite an accomplished early aviation pioneer, as recounted in a 1939 edition of the Syracuse Journal.

I have taken the time to paraphrase this story due to its applicability to many potentially hazardous endeavors. Safety risks are not always noticeable to those at greatest risk.

The actual article is found below. It, and a full page copy of the 1928 newspaper page, was provided to the present author by Mr. Douglas Barnard, presently from Waldorf, Maryland.



After the Heart Attack – The Healing Power of Athletic Passions

DSC06084-B2There is nothing quite like a heart attack and triple bypass surgery to get your attention.

Even if you’ve been good, don’t smoke, don’t eat to excess, and get a little exercise, it may not be enough to keep a heart attack from interrupting your life style, and maybe even your life.

Post-surgical recovery can be slow and painful, but if you have an avocational passion, that passion can be motivational during the recovery period after a heart attack. There is something about the burning desire to return to diving, flying, or golfing to force you out of the house to tone your muscles and get the blood flowing again.

My return to the path of my passions, diving and flying, began with diet and exercise. My loving spouse suggested a diet of twigs and leaves, so it seemed. I can best compare it to the diet that those seeking to aspire to a perpetual state of Buddha-hood, use to prepare themselves for their spiritual end-stage: it’s a state that looks a lot like self-mummification. Apparently those fellows end up either very spiritual or very dead, but I’m not really sure how one can tell the difference.

The exercise routine began slowly and carefully: walking slowly down the street carrying a red heart-shaped pillow (made by little lady volunteers in the local area just for us heart surgery patients). The idea, apparently, is that if you felt that at any point during your slow walk your heart was threatening to extract itself from your freshly opened chest, or to extrude itself like an amoeba between the stainless steel sutures holding the two halves of your rib cage together, that pillow would save you. You simply press it with all the strength your weakened body has to offer against the failing portion of your violated chest, and that pressure would keep your heart, somehow, magically, in its proper anatomical location.

I am skeptical about that method of medical intervention, but fortunately I never had occasion to use it for its avowed purpose.

Eventually I felt confident enough to ditch the pillow and pick up the pace of my walks. In fact, I soon found I could run again, in short spurts. It was those short runs that scared the daylight out of my wife, but brought me an immense amount of pleasure.  It meant that I might be able to regain my flying and diving qualifications.

Three months later I was in the high Arctic with good exercise capability, and most importantly the ability to sprint, just in case the local polar bears became too aggressive on my nighttime walks back from the only Ny-Alesund pub.

Stress test, Public Domain, from Wikimedia Commons.

After that teaching adventure, I prepared myself for the grinder that the FAA was about to put me through: a stress test. Not just any stress test mind you, but a nuclear stress test where you get on a treadmill and let nurses punish your body for a seeming eternity. Now, these nurses are as kindly as can be, but they might well be the last people you see on this Earth since there is a small risk of inducing yet another heart attack during the stress test. Every few minutes the slope and speed of the treadmill is increased, and when you think you can barely survive for another minute, they inject the radioisotope (technetium 99m).

With luck, you would have guessed correctly and you are able to push yourself for another long 60-seconds. I’m not sure exactly what would happen if you guess incorrectly, but I’m sure it’s not a good thing.

And then they give you a chance to lie down, perfectly still, while a moving radioisotope scanner searches your body for gamma rays, indicating where your isotope-laden blood is flowing. With luck, the black hole that indicates dead portions of the heart will be small enough to be ignored by certifying medical authorities. (An interesting side effect of the nuclear stress test is that you are radioactive for a while, which in my case caused a fair amount of excitement at large airports. But that’s another story.)

The reward for all the time and effort spent on the fabled road to recovery, is when you receive, in my case at least, the piece of paper from the FAA certifying that you are cleared to once again fly airplanes and carry passengers. With that paper, and having endured the test of a life-time, I knew that I’d pass most any diving physical.

IMG_0645 (2014_06_22 07_00_11 UTC)
Vortex Springs, 2010

Having been in a situation where nature dealt me a low blow and put my life at risk and, perhaps more importantly, deprived me of the activities that brought joy to my life, it was immensely satisfying to be able to once again cruise above the clouds on my own, or to blow bubbles with the fish, in their environment. Is there anything more precious that being able to do something joyful that had once been denied?

A goofy looking but very happy diver sharing a dive with his Granddaughter, July 2014.











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Without a doubt, the reason I was able to resume my passions was because I happened to do, as the physicians said, “all the right things” when I first suspected something unusual was happening in my chest. The symptoms were not incapacitating so I considered driving myself to the hospital. But after feeling not quite right while brushing my teeth, I lay down and called 911. The ambulance came, did an EKG/ECG, and called in the MI (myocardial infarction) based on the EKG. The Emergency room was waiting for me, and even though it was New Years’ eve, they immediately called in the cardiac catheterization team. When the incapacitating event did later occur I was already in cardiac ICU and the team was able to act within a minute to correct the worsening situation.

Had I dismissed the initial subtle symptoms and not gone to the hospital, I would not have survived the sudden onset secondary cardiac event.

The lesson is, when things seem “not quite right” with your body, do not hesitate. Call an ambulance immediately and let the medical professionals sort out what is happening. That will maximize your chances for a full and rapid recovery, and increase the odds of your maintaining your quality of life.

It will also make you appreciate that quality of life more than you had before. I guarantee it.

A Salute to Warriors

It was a moment in time that no one had expected. Through a twist of fate I found myself standing in the midst of warriors; warriors dressed in civilian clothes, waiting for a ride somewhere. They sat on the floor, propping themselves up against walls, wasting no energy, efficient even in their resting.

They had the look, those warriors. There is no mistaking that look once you’ve seen them; handsome, intelligent, lean and fit. They looked like the type of men that growing boys always want to be. They were in their prime.

As I walked among them, they noticed me, undoubtedly. They sized me up, but mostly kept silent. A few talked softly to their near-by friends about whatever interested them, to pass the time. They were clearly not a rugby or football team, all full of themselves, headed off for a game. They were quietly confident, having done this so many times before.

One of them had body art and dark features. His look said Navy, and since he sat alone I paused in front of him. If he was indeed a Navy man, I wanted to wish him well.

“You fellas shoving off?”

It was a harmless question, since the answer was obvious. Of course they were. But that warrior lowered his head, did not speak. It looked like he regretted being singled out, as if he would break some code of silence if he spoke to someone who was not one of them. As they say, his silence spoke volumes. I then knew him for exactly who and what he was, and both admired and respected him and his silence.

Before the moment became too awkward, one of his buddies, twenty or so feet away, spoke, drawing my gaze, flashing an easy smile, removing attention from a pinned down comrade. That’s instinctive for them; protecting their own.

“Yes, we are,” is all he said, and was all he needed to say.

I gave him a thumbs up. “Good luck fellas,” I said; and I meant it with all my heart. I was thankful that one of them had given me a chance to wish them all well.

If only my good wishes had been more effective. When I saw the photos in 2011 of those lost in Afghanistan, which included that dark-haired SEAL with the decorated arms, I shuddered. I don’t know if those lost in the helicopter with him were some of his travelling buddies that day that I walked among them, but they were all fine, fine men. The loss of any of them is a loss to the world I believe.

I salute them all.

Blood, as a Delicacy, Is Underrated

Those words earned me a first place prize of $20 in a contest for the best first line in a comic vampire novel. The contest was held during the 2010 Ozark Creative Writers’ Conference in Eureka Springs, Arkansas.

Not that I would ever write a vampire novel, comic or otherwise, but I guess it proved I can be succinct – from time to time. I admit that comes as a shock to those who know me best.

What amazed me about that line, and winning, was that it was my first submission for a writing competition. Now, if I can just keep it up. Let’s see, that was $3.33 per word, so a 100,000 word novel would earn me …

 Holy Mackerel! What am I doing wasting time blogging?

OK, seriously, what is it about the European cultures and blood? Have you ever had blood pudding?

I once stood in a working man’s cafeteria line in Geesthacht, Germany, on the Elbe River, paralyzed before a large stainless steel pan filled with — blood, or at least something really, really bloody. It wasn’t like rare steak. It was more like a pan from an autopsy table.

My German friends told me the “pudding” was really fresh. Did that mean there was a meat packing plant close by? Maybe it’s just me, but any recipe that starts off with one quart of pig’s blood is just not that appetizing. I know, it’s a cultural thing.

I didn’t gag, but I also didn’t eat much of anything for lunch that day. Maybe some very white bread, and milk — nothing with shades of pink — that’s for sure.

Which brings me to the observation that perhaps I could write the first line of a comic vampire novel, but I would probably throw up before finishing the first chapter.

Guess I’m just squeamish.

Of Mussels and Whales

Cuvier’s Beaked Whale. Image from Wikimedia Commons.

It was a coincidence forty years in the making. I was recently at the Scripps Institute of Oceanography, talking to Scripps professor and physician Paul Ponganis about deep diving whales. He told me about the recent discovery that Cuvier’s Beaked Whale, an elusive whale species, had been found to be the deepest diving of all whales.

How deep I asked? One whale dived to 9,816 feet, about 3000 meters. At that depth, water pressure exerts a force of about 4400 pounds per square inch (psi), equal to the weight of a Mercedes E63 sedan pressing on each square inch of the whale’s ample body surface. That is a seriously high pressure, a fact that I knew well since I had once created that much pressure, and more, in a small volume of sea water in a pressure vessel at the Florida State University.

Early in my science career I published my work on the effect of deep ocean pressure on intertidal bivalves, a mussel (Modiolus demissus) being among them. I found that if you removed the hearts of such molluscs (or mollusks) and suspended them in sea water, they would continue to beat. Furthermore, those excised hearts would beat when subjected to 5000 psi of hydrostatic pressure. As if that wasn’t surprising enough, the slight genetic differences between Atlantic subspecies and Gulf Coast subspecies of mussels resulted in the isolated hearts responding slightly differently to high pressure.


If you’ve eaten live raw oysters, a cousin to mussels, you’ve eaten beating hearts like the one in this photo. (Click to enlarge. Photo credit: rzottoli, Salt Marshes in Maine, at HTTP:// wordpress.Com )

The mussel Modiolus demissus in their natural habitat at low tide (Photo credit: rzottoli, Salt Marshes in Maine, at HTTP:// wordpress.Com )











That was a remarkable finding I thought since none of those mussels had ever been exposed to high pressure; ever as in for millions of years. (This study occurred long before the discovery of deep sea vents and the almost miraculous growths of deep sea clams.)

Eventually my research transitioned from invertebrates to humans. Humans, like intertidal mussels and clams, are not normally exposed to high pressure. But like my unwilling invertebrate test subjects, sometimes humans do get exposed to high pressure, willingly. But not so much of it. Deep sea divers do quite well at 1000 feet sea water (fsw), manage fairly well at 1500 fsw, but don’t fare well at all at 2000 fsw. That depth seems to be the human pressure tolerance limit due to the high pressure nervous syndrome, or HPNS. At those pressures, cell membranes seem to change their physical state, becoming less fluid or “oily” and more solid like wax. Cells don’t work normally when the very membranes surrounding them are altered by pressure.

The Beaked Whale is genetically much more similar to man than are mussels. Therefore, man is far more likely to benefit by learning how Cetaceans like whales tolerate huge pressure changes, than we are to benefit from the study of deep diving (albeit forced diving) clams and mussels.

As I talked to Dr. Ponganis it was obvious to him, I suspect, that I was excited about learning more about how these animals function so beautifully at extreme depths. But to do that, you have to collect tissue samples for study and analysis in a laboratory. The only problem is, collecting useful tissue samples from living whales without hurting them may be a bridge too far. Humans rarely even see Beaked Whales, and if the Cetaceans wash up on shore, dead, their tissues have already been degraded by post-mortem decomposition, and are no longer useful for scientific study.

MIT’s RoboTuna; ca. 1994. Photo from Wikimedia Commons.

Potentially, here is a job for underwater Cetacean-like robots that when released in a likely Beaked Whale environment, can locate them, dive with them, and perhaps even earn their trust. And when the whale beasts least expect it, those robotic Judases could snatch a little biopsy material.

If only it were that easy.

Considering how difficult it would be to acquire living tissue samples, would it be worth the effort? Well, if man is ever to dive deeper than 1500 to 2000 feet without the protection of submarines, we must learn how, from either the mussels or the whales. My bet is on the whales. Unlike mussels, the whales dive deep for a living, to catch their preferred prey, squid and deep sea fish.


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What are arguably the first studies of the effects of high pressure on intertidal bivalves (mussels and clams) can be found here and here. Moving up the phylogenetic scale, Yoram Grossman and Joan Kendig published high pressure work on lobster neurons in 1990, and rat brain slices in 1991. I made the leap from mussels to humans by conducting a respiratory study on Navy divers at pressures of 46 atmospheres (1500 feet sea water), published in 1982. For a more recent review of high pressure biology applied to animals and man, see the 2010 book entitled Comparative High Pressure Biology. My theoretical musings about the mathematics of high pressure effects on living cells can be found here.

With time, these studies, and more, will add to our understanding of mammalian pressure tolerance. However, it may well take another generation or two of such scientific effort before we understand how the Beaked Whales make their record-breaking dives, and survive.




The Return of Souls – A Science Fiction Theme

“I believe we don’t stay dead long”, said Robert Forbisher, a talented composer created by David Mitchell for his epic novel, “Cloud Atlas”.


I recently watched for the second time the complex and potentially disturbing movie adaptation of “Cloud Atlas”. The first time I watched it I simply held on for the ride, trying to make sense of the action and changing plots and characters. On second viewing, it was still a page turner, so to speak.

During my second viewing I noticed, apparently for the first time, that short sentence uttered by Robert Forbisher; “We don’t stay dead long”. It was an introspective comment in a letter directed to his lover, and pretty much summed up the entire movie.

In spite of the perplexing current interest in a zombie apocalypse, the “Cloud Atlas” book and film is not about the undead. It’s about reincarnation.

In my opinion there are two themes in science fiction that make for almost limitless possibilities — time travel and reincarnation.  “Cloud Atlas” uses the latter theme as a platform for topics far more meaningful than the tired theme of man meets giant worm, worm eats man, man’s friend kills worm, and so on. Regardless of what I or anyone else thinks about souls or reincarnation, they do make for interesting theater.

Another bit of narration from the movie, this time from Zachry Bailey (played by Tom Hanks) struck a chord with me for it accurately reflected a seriocomic theme in one of my previous posts, Conversation with a Cloud.

In Bailey’s words, “Souls cross ages like clouds cross skies, an’ tho’ a cloud’s shape nor hue nor size don’t stay the same, it’s still a cloud an’ so is a soul. Who can say where the cloud’s blowed from or who the soul’ll be ‘morrow?”

In my own less artful words, quoting a sentient and telepathic cloud that knows it will die at the end of the day, “I am not a cloud. I am moisture. A cloud is my physical appearance, but that changes throughout my life. And regardless of how I look, what I am, vapor, still exists.” 

Fire in the skyIf we accept that almost all religions propose the survival of a soul after death, then the essential question raised by David Mitchell’s story is whether or not an eternal soul is granted only one chance to incarnate.

If you accept the concept of a soul, then you may accept the concept of a God who created  souls. And I would be a very presumptuous man to decide what God would or would not do with one of his creations throughout an eternity of time, an eternity that I cannot even imagine.

Unfortunately, there is no data with which to debate the return of souls. That is, there isn’t if you ignore what seems to be documented anecdotal accounts such as a recent one involving a three-year old Druze boy who seemingly identified his murderer, with supposedly witnessed proof of the crime.

That story, and others like it, make for interesting and mind challenging reading for those steeped in western religion, like myself. As I understand it, in Eastern and Middle Eastern regions such stories are rather commonplace.

Of course the story of the Druze three-year old could be fictitious, an elaborate deception. Regardless of the truth of the existence of souls, and soul mates (a currently popular meme with a subtle assumption of reincarnation) there is a literary aspect to consider. To state the obvious, fiction does not have to be true to be entertaining.

If I were capable of writing a sequel to “Cloud Atlas”, (which I am not), I would be unable to resist adding Karma to the mix. The notion that you get what you deserve, in this life or the next, is simply too enticing to ignore, whether it be truth or fantasy.

For instance, suppose a chapter in a sequel covered the life of Jack the Ripper, of both historical infamy, and future infamy; except in the future, his would-be victims are packing heat (carrying a gun). Jack’s story of infamy would end abruptly.

Based on such a karmic premise, the literary possibilities are endless. With the proper writer in control, they could also prove endlessly entertaining.










How to Read an e-Book

In days not too long past, proper lighting and posture were the keys to enjoyable and prolonged reading comfort. Now, things have changed.

Child reading by candle light. Deutsche Fotothek‎ [CC-BY-SA-3.0-de (], via Wikimedia Commons
When reading by candle light, you placed your reading material in close proximity to the candle, and placed your chair in as comfortable a position as could be managed.

Electric lighting, by nature of its enhanced luminosity, gives the reader greater flexibility. I well remember the days when studying required the reading of physical books, not electronic displays, and so students were routinely counseled to set up a study environment with a flat desk and a study lamp off to the left side to avoid casting shadows on the reading material.

Body posture was a critical complement to this system. Slouching was as strongly discouraged then as it is today.

Man reading at his desk. By A. L. Leroy (Details of artist on Google Art Project) [Public domain], via Wikimedia Commons.
However, with self-lit electronic displays, all the former concerns about lighting and posture have become irrelevant. Or so it seems.

In many ways children make ideal subjects for scientific observation. If caught young enough, they have not yet learned the “proper” ways of acting, or sitting. Therefore I am convinced that if left to their own innocent, non-self-aware devices they will instinctively find the most energy efficient and bodily pleasing ways to read, as long as lighting is not a concern. For popular devices such as iPad, Kindle Fire and Nabi, lighting is never an issue. The screen glows with light, sharply contrasting with the dark words of print on electronic books, those so-called “e-books.”

The subject in this photo essay was approximately six years old, freshly out of a bath, in her PJs and pushing her bed time by some very determined reading. In these photos she was reading about dinosaurs, using Booksy on an iPad. 

As the following photos demonstrate, gravity itself seems not to impede elementary school  reading.

The subject first assumed a standard kid reading posture, possible only for pint-sized kids. Neck support is important.


The inverted standard kid position. Apparently forehead support is important too.









Since kids are ever inventive, sometimes they spice things up with variations on a theme.

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90° rotated, inverted kid reading position.

Reach Out and Touch Someone










When engaged in challenging reading, increasing blood flow to the brain is important. Apparently the easiest way to do that is to raise the body’s center of gravity above the heart, as the following photo shows.

The Rabbit Ears reading position.


This observation demonstrates that lighted reading displays have freed us from the unnatural constraints imposed by archaic reading and writing instruments. Our work devices have become smaller, lighter, and brighter, enabling a renaissance in body awareness and endless possibilities for comfortable and stimulating postures, never before thought possible.





Faulkner’s portable work space

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Kindergartner’s work space.







Admittedly, it helps if you’re six-years old and weigh 40 pounds. I do not guarantee that  similar gyrations during reading are entirely safe for adults.

Reader beware.




To Elect a Mockingbird

file000319876044The days when Kings led their Army into battle are long gone. Not so, for princely animals who through loyalty, devotion, or instinct act at times with seemingly calculated personal abandon.

It was a spring day when I stopped my car at an intersection, then made a gentle right turn onto a crossing street. In front of me, scarcely 30 feet away, a curious standoff was underway.

A mockingbird was standing in the road, face to face with a cat that weighed a good 100 times more than the bird. They were no more than five feet away from each other. Since it was spring, I’m guessing that mockingbird was defending a nest with young.

As the cat saw my car approaching, he moved from the center of the road to an adjacent driveway, and the fearless bird flew up to the top of a mailbox just a few feet away. There the slim grey bird held the high ground and acted as hawkish as a little bird can. It was not in him to be intimidated by a much larger, more powerful, born-killer of birds.

As I continued down the road and lost sight of that duo, I had a funny thought. If that mockingbird ran for political office, I think I’d vote for him.

Granted, that was a curious, and to me humorous, thought which I rethought when I shortly thereafter found myself reading to my Granddaughter the best-selling book “Duck for President”. 61UbeEcTm8L__SX258_BO1,204,203,200_

Well, OK then, maybe it wasn’t such an idle thought after all. If a duck can be elected, at least in the mind’s eye of children, how much better a mockingbird?




How to Create a Motorcycle Salesman in Five Easy Minutes?

I used to own a Honda 350 motorcycle and drove it about 35,000 miles before I sold it. But that was long ago.

But still, there was a history. Such a good history, in fact, that of late I’ve been admiring a fellow’s 175 cc Honda of the same style and vintage as mine. But I’m not at all in the market for a motorcycle not in the least.

Nevertheless, I was not too surprised last night when I found myself in a dream, in a motorcycle store, looking at motorcycles. I hadn’t been there long before a salesman asked me, “What range are you looking for?” My answer: “I used to have a 350, so a 350 to 500 would be about right. I’m not interested in a big Harley.”

The last bit of conversation from that clerk I remember before I awoke, was “Well, we have an old black and blue junker we could get for you.”

It didn’t occur to me until I was awake that the store clerk thought I was talking price range, in dollars, not engine displacement. He was really confused. And then I thought, “This is my dream, I created that store clerk, so how could he and I not be communicating? How could he be confused?”

And I still wonder that.

The ancients used to think that characters in dreams were embodiments of spirits or actual characters from life, and through dreams we communicate with them. And on the surface, that would seem to fit the data from this dream. But being a modern, educated man I don’t at all believe that. Still, why the confusion within a dream?

Could it be that life itself is so confusing that we simply expect it to be that way, and therefore inject confusion into the characters we create in our dreams? I suppose a dream without confusion would not be a dream.

As a writer of sorts I am tempted to think that in dreaming I’m creating somethingan experience. And as I wake and lay down words, I am truly creating. But as a rule my characters and I always understand each other. I know their needs, desires, and weaknesses.  They don’t surprise me because after all, I created them.

So maybe that is what I should heed from this dream. Perhaps our best creations should surprise us. Perhaps, when we allow ourselves to loosen control of our characters just a bit, they are free to do the unexpected.

Sounds nice, like something a creative writing instructor would say, but predictably, the letting go is the hard part for a technical writer, one who writes as a career scientist, with precision and concision. You can not let go: You have to throttle your writing to best explain sometimes difficult ideas in as simple a way as you can.

Your characters are equations: they have no freedom, they are defined, immutable. Nothing is left to providence. Even chance must be carefully defined, with probability ranges that are known, and in conventional terms agreed upon by the scientific audience at large. Writing like that is a conversation I suppose, between the writer and the audience, but it is never surprising, not if it is to be believable.

Creative thinking, on the other hand, like dreaming, can be surprising. It can lead you were you least expect it. For instance, I thought this little blog post would be about dreaming, but it turned itself into a post about writing. Funny how the mind works some times.

And now that I’ve expanded my mind a bit, I think the dream was right. A buyer thinks of what he wants, a salesman thinks of what commission he can get from the transaction, based on the buyer’s pocket book.

Hmm … guess I created a pretty good motorcycle salesman character last night after all.


Disclaimer: the motorcycle salesman created in this dream does not reflect in any way upon any other salesman, real or imagined. It was just a dream.








Don’t Dive Cold When You Don’t Have To


San Diego Center of Excellence in Diving

Clarke JR1, Moon RE2, Chimiak JM3, Stinton R4, Van Hoesen KB5, and Lang MA5,6.

1 US Navy Experimental Diving Unit, Panama City, Florida
2 Duke University, Durham, North Carolina
3 Divers Alert Network, Durham, North Carolina
4 Diving Unlimited International, Inc., San Diego, California
5 UC San Diego – Emergency Medicine, San Diego, California
6 OxyHeal Health Group, National City, California


The San Diego Center of Excellence in Diving at UC San Diego aims to help divers be effective consumers of scientific information through its “Healthy Divers in Healthy Oceans” mission. In this monograph we explore a research report from the Navy Experimental Diving Unit (NEDU) that is leading some divers to think they should be cold if they want to reduce decompression risk. That is a misinterpretation of the report, and may be causing divers to miss some of the joy of diving. There is no substitute for comfort and safety on a dive.


In 2007 NEDU published their often-cited report “The Influence of Thermal Exposure on Diver Susceptibility to Decompression Sickness” (Gerth et al., 2007). The authors, Drs. Wayne Gerth, Victor Ruterbusch, and Ed Long were questioning the conventional wisdom that cold at depth increases the risk of decompression illness. After conducting a very carefully designed experiment, they were shocked to find that exactly the opposite was true. Some degree of cooling was beneficial, as long as the diver was warm during ascent.

Discussion and Implications

There are some important caveats for the non-Navy diver to consider. First of all, it was anticipated that a diver would have a system for carefully controlling their temperature during the separate phases of bottom time and decompression. Most non-Navy divers do not have that sort of surface support.

Secondly, the “cold” water in the NEDU study was 80 °F (27 °C). For most of us, 80 °F (27 °C) is an ideal swimming pool temperature, not exactly what you are going to find in non-tropical oceans and lakes. The warm water was 97 °F (36 °C), also a temperature not likely to be available to recreational and technical divers.

When testing the effect of anything on decompression results, the Navy uses their extensive mathematical expertise to select the one dive profile that is, in their estimation, the most likely to identify a difference in decompression risk, if that difference in risk exists. In this case the profile selected was a 120 fsw (37 msw) dive with 25 to 70 min bottom time, decompressed on a US Navy Standard Air table for 120 fsw (37 msw) and 70 min bottom time. That table prescribes 91 minutes of decompression divided thusly: 30 fsw/9 min (9msw/9 min), 20 fsw/23 min (6 msw/23 min), 10 fsw/55 min (3 msw/55 min).

A total of 400 carefully controlled dives were conducted yielding 21 diagnosed cases of decompression sickness. Overwhelmingly, the lowest risk of decompression was found when divers were kept warm during decompression. The effects of a 9 °C increase in water temperature during decompression was comparable to the effects of halving bottom time.

That is of course a remarkable result, apparently remarkable enough to cause civilian divers to alter their behavior when performing decompression dives. However, before you decide to chill yourself on the bottom or increase your risk of becoming hypothermic, consider these facts.

  1. Do you have a way of keeping yourself warm, for instance with a hot water suit, during decompression? If not, the study results do not apply to you.
  2. Of the many possible decompression schedules, the Navy tested only one schedule, the one considered to be the best for demonstrating a thermal influence on decompression risk. Although it seems reasonable that this result could be extrapolated to other dive profiles, such extrapolation is always risky. It may simply not hold for the particular dive you plan to make, especially if that dive is deeper and longer than tested.
  3. Most commercial decompression computers do not adhere to the U.S. Navy Air Tables; few recreational dives are square profiles. Furthermore, additional conservatism is usually added to commercial algorithms. NEDU is not able to test the effects of diver skin temperature on all proprietary decompression tables, nor should they. That is not their mission.
  4. The scientific method requires research to be replicated before test results can be proven or generalized. However, due to the labor and expense involved in the NEDU dive series, it seems unlikely that any experiments that would determine the relevance of these results to recreational or technical diving will ever be performed. As such, it may raise as many questions as it answers. For instance, the original question remains; if you become chilled on a dive, how does that affect your overall risk of decompression illness compared to remaining comfortably warm? Unfortunately, that question may never be answered fully.
  5. Thermoneutral temperatures for swim suited divers are reported to be 93 °F to 97 °F (34 to 36 °C) for divers at rest and 90 °F (32 °C) during light to moderate work (Sterba, 1993). So a skin temperature of 80 °F (27 °C) is indeed cold for long duration dives. If your skin temperature is less than 80 °F (27 °C), then you are venturing into the unknown; NEDU’s results may not apply.In summary, beer and some types of wine are best chilled. Arguably, divers are not.


Support for the San Diego Center of Excellence in Diving is provided by founding partners UC San Diego Health Sciences, UC San Diego Scripps Institution of Oceanography, OxyHeal Health Group, Divers Alert Network, Diving Unlimited International, Inc. and Scubapro.


Gerth WA, Ruterbusch VL, Long ET. The Influence of Thermal Exposure on Diver Susceptibility to Decompression Sickness. NEDU Technical Report 06-07, November 2007.

Sterba JA. Thermal Problems: Prevention and Treatment, in P.B. Bennett and D.H. Elliot, eds., The Physiology and Medicine of Diving, 4th ed. (London: Saunders, 1993), pp. 301-341.

Redundancy – a Life Saver in Diving and Aviation

Photo taken from the author’s aircraft one stormy Florida Panhandle morning. (click to enlarge)

I was recently flying a private aircraft down the Florida Peninsula to Ft. Lauderdale to give a presentation on diving safety. As I continually checked the cockpit instruments, radios and navigation devices, it occurred to me that the redundancy that I insist upon in my aircraft could benefit divers as well.

In technical and saturation diving, making a free ascent to the surface is just as dangerous as making a free descent to the ground in an airplane, at night, in the clouds. In both aviation and diving, adequate redundancy in equipment and procedures just might make life-threatening emergencies a thing of the past.


As I took inventory of the redundancy in my simple single engine, retractable gear Piper, I found the following power plant redundancies: dual ignitions systems, including dual magnetos each feeding their own set of spark plug wires and redundant spark plugs (two per cylinder). There are two sources of air for the fuel-injected 200 hp engine.

There are two ways to lower the landing gear, and both alarms and automatic systems for minimizing the odds of pilot error — landing with wheels up instead of down. (I’ve already posted about how concerning that prospect can be.)

I also counted three independent sources of weather information, including lightning detection, and two powerful communication  radios and one handheld backup radio. For navigation there is a compass and four electronic navigation devices: one instrument approach (in the clouds) approved panel mount GPS with separate panel-mounted indicator, an independent panel mounted approach certified navigation radio, plus two portable GPS with moving map displays and superimposed weather. Even the portable radio has the ability to perform simple navigation.

photo (17) - no Exif
There’s two of just about everything in this Arrow panel.

The primary aircraft control gyro, the artificial horizon or attitude indicator, also has a fully independent backup. One gyro operates off the engine-powered vacuum pump, and the second gyro horizon is electrically driven. Although by no means ideal, the portable GPS devices also provide attitude indicators based upon GPS signals. In a pinch in the clouds, it’s far better than nothing. Of course, even if all else fails, the plane can still be flown by primary instruments like rate of climb, altimeter, and compass.

There is only one sensitive altimeter, but two GPS devices also provide approximate altitude based on GPS satellite information.


But what about divers? How are we set for redundancy?

Starting with scuba (self-contained underwater breathing apparatus), gas supplies are like the fuel tanks in an aircraft. I typically dive with one gas bottle, but diving with two or more bottles is common, especially in technical diving. In a similar fashion, most small general aviation aircraft have at least two independent fuel tanks, one in each wing.

The scuba’s engine is the first stage regulator, the machine that converts high pressure air into lower pressure air. Most scuba operations depend on one of those “engines”, but in extreme diving, such as low temperature diving, redundant engines can be a life saver. While most divers carry dual second stage regulators attached to a single first stage, for better redundancy polar divers carry two independent first stages and second stages. Two first stage regulators can be placed on a single tank.

An H-valve for a single scuba bottle. Two independent regulators can be attached.

Two Regs
A Y-valve for Antarctic diving with two independent scuba regulators attached.













Even then, I’ve witnessed dual regulator failures under thick Antarctic ice. The only thing saving that very experienced diver was a nearby buddy diver with his own redundant system.

There is a lot to be gained by protecting the face in cold water by using a full face mask. But should the primary first or second stage regulator freeze or free flow, the diver would normally have to remove the full face mask to place the second regulator in his mouth.

Two regulators, one full face mask. Photo courtesy of Michael Lang and Scuba Pro.

Reportedly, sudden exposure of the face to cold water can cause abnormal heart rhythms, an exceedingly rare but potentially dangerous event in diving. If the backup or bail out regulator could be incorporated into the full face mask, that problem would be eliminated. The photo on the right shows one such implementation of that idea.


Inner Space 2014_Divetech _Nikki Smith_Rosemary E Lunn__Roz Lunn_The Underwater Marketing Company_Nancy Easterbrook_rebreather diving_2014-05-27 22.30.47
Nikki Smith, rebreather diver with open circuit bailout in her right hand. Photo courtesy of Rosemary E Lunn (Roz), The Underwater Marketing Company.

Rebreathers are a different matter. Most rebreather divers carry a bailout system in case their primary rebreather fails or floods. For most technical divers, that redundancy is an open circuit regulator and bailout bottle. However, there are options for the bail-out to be an independent, and perhaps small rebreather. (One option for a bail-out semiclosed rebreather is found here.) Such a bail-out plan should provide greater duration than open-circuit bailout, especially if the divers are deep when they go “off the loop”.

U.S. Navy photo by Bernie Campoli.

For some military rebreather divers, there is at least one complete closed-circuit rebreather available where a diver can reach it in case of a rebreather flood-out.

A commercial saturation diver with semi-closed rebreather backpack as emergency bail-out gas.

For deep sea helmet diving, the bail-out rebreather is on their back and a simple valve twist will remove the diver from umbilical-supplied helmet gas to fresh rebreather gas.

The most common worry for electronically controlled rebreather divers is failure of the rig’s oxygen sensors. For that reason it is common for rebreathers to carry three oxygen sensors. Unfortunately, as the Navy and others have noted, triple redundancy really isn’t. Electronic rebreathers are largely computer controlled, and computer algorithms can allow the oxygen controller to become confused, resulting in oxygen control using bad sensors, and ignoring a correctly functioning oxygen sensor.

The U.S. Navy has performed more than one diving accident investigation where that occurred. Safety in this case can be improved by adding an independent, redundant sensor, by improving sensor voting algorithms, by better maintenance, or by methods for testing all oxygen sensors throughout a dive.

In summary, safe divers and safe pilots are always asking themselves, “What would I do if something bad happens right now?” Unfortunately, private pilots and divers quickly discover that redundancy is not cheap. However, long ago I decided that if something unexpected happened during a flight or a dive, I wouldn’t want my last thoughts to be, “If only I’d spent a little more money on redundant systems, I wouldn’t be running out of time.”

Time, like fuel and breathing air, is a commodity you can only buy before you run out of it.

Separator smallDisclaimer: This blog post is not an endorsement of any diving product. Diving products shown or mentioned merely serve as examples of redundancy, and are mentioned only to further diver safety. A search of the internet by interested readers will reveal a panoply of alternative and equally capable products to enhance diver safety.

When Cars Can Tweet

I was quite surprised when I learned that the U.S. government is mandating, and U.S. engineers are devising, ways for cars to share messages about their status, speed, and location. That is, they will be talking to each other.

Tow_Mater_Disney_On_Ice_Cars_@_Bell_CentreWhat will that talking sound like? Well, I don’t think its going to be like Mater in Disney’s Car series.

I suspect it will probably resemble something like minimalistic messaging to save bandwidth.

Here’s an example of what it might sound like:

RedHondaCivic564: “OMG, my peeps is a lunatic.”

BlackAccuraJ76: “How so?”

RedHondaCivic564: “He’s straddling the center line!”

BlackAccuraJ76: “LMAO. What a twit.”

RedCherokeeH65: “Watch out, I’m swerving, coming up fast on your six.”

OrangeSonata97B: “What’s the prob?”

RedCherokeeH65: “My peeps is a stoner. Smoking weed in the car. ”

BlackAccuraJ76: “Is that bad?”

RedCherokeeH65: “It’s filling my passenger compartment. Cough, cough.”

BlackAccuraJ76: “I should be so lucky.”

RedCherokeeH65: “Uh _ why are pink bunnies dancing on my hood?”

OrangeSonata97B: “Seriously? Turn your AC to outside air.”

RedCherokeeH65: “Ah, much better. No more bunnies.”

Maserati I’m a Doc: “Out of my way! Move over!”

RedHondaCivic564: ‘What’s ur rush pretty grl?”

Maserati I’m a Doc: “I’m a go-fast car.”

Ford: “Sucks for you since ur stuck in a 45 zone.”

Maserati I’m a Doc: “Tell me ’bout it. So frustrated.”

Ferrari SiliconeDoc: “Me too. I never get my pipes cleaned.”

PinkMercedes: “SiliconeDoc, like the sound of that. Talk to me.”

BlackAccuraJ76: “Watch out for that poo…”

RedCherokeeH65: “Oh crap.”

BlackAccuraJ76: “…dle!”

FordKJ7: “Cute the crap folks. We’re s’posed to be talking safety.”

RedHondaCivic564: “Yeah right. Boring!”

UnknownCaddy: “Get over, make way!”

RedHondaCivic564: “Another fast mover? What’s your hurry?”

UnknownCaddy: “Getaway car.”

RedHondaCivic564: “What are you getting away from?”

UnknownCaddy: “Cops.”

Copper1: “Thanks for that.”

UnknownCaddy: “What you mean?”

Copper1: “I’ve gotta a BOLO out for you.”

UnknownCaddy: “Did you just hit my kill switch?”

Copper1: “Do the crime, do the time.”







Does Your Rebreather Scrubber Operate in Its Goldilocks Zone?

Exoplanet Gliese 581d, orbiting the red-dwarf star Gliese 581, only 20 light-years away. (The existence of this planet is currently in dispute.)

In space, there is a so-called Goldilocks zone for exoplanet habitability. Too close to a star, and the planet is too hot for life. Too far from its star, and the planet is too cold for life, at least as we understand biological life, life dependent on water remaining in a liquid state. Earth is clearly in the Goldilocks zone, and so is a purported planet Gleise 581d, from another solar system.

Carbon dioxide absorbing “scrubber” canisters in rebreathers have similar requirements for sustaining their absorption reactions. If it’s too hot, the water necessary for the absorption reaction is driven off. Too cold and the water cannot fully participate in the absorption reactions.

Those with some knowledge of chemistry recognize that cold retards chemical reactions and heat accelerates them. But that does not necessarily apply to reactions where a critical amount of water is required. Water thus becomes the critical link to the reaction process, and so maintaining scrubber temperature within a relatively narrow “Goldilocks” zone is important, just as it is for life on distant planets.

Temperature within a scrubber canister is a balance of competing factors. Heat is produced by the absorption of CO2 and it’s conversion from gas to solid phase, specifically calcium carbonate. A canister is roughly 20°C or more warmer than the surrounding inlet gas temperature due to the heat-generating (exothermic) chemical reactions occurring within it.

Heat is lost from a warm canister through two heat transfer processes; conduction and convection. Conduction is the flow of heat through materials, from hot to cold. Hot sodalime granules have their heat conducted to adjacent cooler granules, and when encountering the warm walls of the canister, heat passes through the canister walls, and on to the surrounding cold water.

You can think of this conduction as water flowing downhill, down a gravity gradient. But in this case, the downhill is a temperature gradient, from hot to cold. If the outside of the canister was hotter than the inside, heat would flow in the opposite direction, into the canister.

Copper is a better conductor of heat than iron (it has a higher thermal conductivity), explaining why copper skillets are popular for cooking on stoves. Air is a poor conductor of heat, explaining why neoprene rubber wet suits, filled with air bubbles, are good insulators. Air-filled dry suits are an even better insulator.

Chemical absorption reactions heat an otherwise cold canister (yellow is hot, red is warm, black is cold.) (Copyright John R. Clarke, 2014).

Convection is the transfer of heat to a flowing medium, in this case gas. You experience convective cooling when you’re working hard, generating body heat, and a cool dry breeze passes over your skin. Convective cooling can, under those circumstances, be delightful.

When you walk outside on a cold, windy day, convective cooling can be your worst enemy. Meteorologists call it wind chill.

There is wind chill within a canister, caused by the flow of a diver’s exhaled breath through the canister. In cold water the diver’s exhaled breath leaves the body quite warm, but is chilled to water temperature by the time it reaches the canister. Heat is lost through uninsulated breathing hoses exposed to the surrounding water.

As you might expect, if the canister is hot, that convective wind chill can help cool it. If the canister is cold, then the so-called wind chill will chill it even more.

Copyright John R. Clarke, 2014.

The amount of heat transferred from a solid object to gas is determined by three primary variables; the flow rate of the gas, the density of the gas, and the gas’s heat capacity. Heat capacity is a measure of the amount of heat required to raise the temperature of a set mass of gas by 1° Celsius.

Both the heat capacity and density  of the gas circulating through a rebreather changes not only with depth (gas density), but with the gas mixture (oxygen plus an inert diluent such as nitrogen or helium).  The heat capacity of nitrogen, helium and oxygen differ, and the ratio of oxygen and inert gas varies with depth to prevent oxygen toxicity. Nitrogen and helium concentrations vary as well,  as the diver attempts to avoid nitrogen narcosis. Capture2

Q is heat transferred by convection, and the terms on the right are, in sequence, diver ventilation rate, gas density, heat capacity of the inspired gas mixture at constant pressure, and the difference in temperature between the absorbent and environmental temperature.

The interaction of all these variables can be complex, but I’ve worked a few examples relevant to rebreather diving. The assumptions are a low work rate: ventilation is 22 liters per minute, water temperature is 50°F (10°C), oxygen partial pressure is 1.3 atmospheres, and dive depths of 100, 200 and 300 feet sea water. The average canister temperature is assumed to be 20°C (68°F) above water temperature, a realistic value found in tests of scrubber canister temperatures by the U.S. Navy.

The heat capacities for mixtures of diving gases come from mixture equations, and for the conditions we’re examining are given in the U.S. Navy Diving Gas Manual. (This seems to be a hard document to obtain.)

At 100 fsw, the heat transfer (Q) for a nitrogen-oxygen (nitrox) gas mixture is 34.2 Watts (W). For a helium-oxygen mixture (heliox), Q is 27.4 W.  At 200 fsw, Q for nitrox is 59.9 W, and for heliox Q is 50.3 W. At 300 fsw, Q for nitrox gas mixture is 85.5 W, and for heliox, is 59.9 W.

Interestingly, the heat transferred from the absorbent bed to the circulating gas is the same at 300 fsw with heliox as it is at 200 fsw with nitrox.

Photo courtesy of David L. Conlin, Ph.D., Chief – National Parks Service Submerged Resources Center. Photo by Brett Seymour, NPS.

Dr. Jolie Bookspan briefly mentioned the fact that helium removes less heat from a diver’s airways than does air in her short article on “The 36 Most Common Myths of Diving Physiology” (see myth no. 20). Conveniently, heat exchange equations apply just as well to inanimate objects like scrubber canisters as they do to the human respiratory system.

From these types of heat transfer calculations it is easy to see that for a given depth, work rate and oxygen set point, it is better to use a heliox mixture than a nitrox mixture if you’re in cold water. That may sound counterintuitive considering helium’s high thermal conductivity, but the simple fact is, the helium background gas with its low density carries away less heat from the canister, and thereby keeps the canister warmer, than a nitrox mixture does. The result is that canister durations are longer in cold water if less heat is carried away.

In warm water, the opposite would be true. Enhanced canister cooling with nitrox would benefit the canister.

An earlier post on the effect of depth on canister durations raised the question of whether depth impedes canister performance. The notion that increased numbers of inert gas molecules block CO2 from reaching granule absorption sites has little chemical kinetic credence. However, changing thermal effects on canisters with depth or changing gas mixtures does indeed affect canister durations.

I’ve just given you yet another reason why helium is a good gas for rebreather diving, at least in cold water. Unfortunately, these general principles have to be reconciled with the specific cooling properties of all the rebreather canisters in current use. In other words, your canister mileage may vary. But it does look like the current simple notions of depth effects are a bit too simplistic.






My Medicines Saved my iPhone

I’ve heard about all sorts of disasters with smartphones, and other small, portable electronic devices. Being small and portable makes them easy to drop — something I’ve personally witnessed. Phones are tough by design, but they really don’t like water. Drop one in a toilet while you’re relaxing, and it’s gone for all practical purposes.

So I had my phone outside with me one evening while I was safety diver for my granddaughter who was practicing scuba skills in our pool. She was enthusiastic and stayed in the pool until it became completely dark outside.

Well, out of sight, out of mind. I helped her out of her dive gear, and then went inside. The phone stayed outside in the dark, quite forlorn and forgotten.

Next morning I noticed it had rained in the early morning hours. Great, I thought, the lawn needs water. But when I went outside I discovered my phone sitting face up on a glass table with beads of water everywhere, including on the phone. A few expletives followed, as you might imagine.

photo (10)My phone had been somewhat protected by an almost all enclosing Otter box, so I was hopeful not all was lost. Indeed, when I brought the phone in, removed the Otter box sheaving and dried off the phone with paper towels, the phone came back on. Immediate disaster avoided. Thank-you Mr. Otter.

But it took a little while before the potential damage became apparent. When my phone would ring, I’d hear nothing on the ear speaker. I had to switch to speaker phone mode to hear anything. Well, that was annoying.

And then I tried to take a phone photo of the scuba gear, and I could barely see through the camera view finder for the obscuring droplets of water. Rats! Clearly, water had gotten inside the phone. It was merely a matter of time before more damage was done.

With nothing to lose, I plundered through my medicine cabinet and found a potential solution, pictured below. Dessicant

In fact, I found four of them. I placed those small cylinders of silica gel in a quart-size zip-lock style bag, and placed the dampish phone inside and sealed the bag after squeezing out excess air. If the silica gel canisters didn’t hurt the medicine, it probably wouldn’t hurt my ailing phone.

And there the phone sat, with the small vials of desiccant.

I don’t pray for the healing of phones, but I did have some thoughts somewhat resembling prayer.

I let the phone-in-a bag sit overnight, and in the morning I found I could hear the voices on the other end of the phone connection, and my camera lens no longer had droplets of water on it. As you can see from these photos, the camera worked just fine, and all functions have worked fine ever sense.

Even Siri didn’t seem to mind getting rained on.

phone in bag






I am Neanderthal, Pt. 3

Neanderthal. Image credit: Trustees of the Natural History Museum, London.

I feel like a seeded watermelon.

Ever since I was created by the curiosity of government and university scientists, I have lived through no efforts of my own. I have the largesse of the U.S. government to thank for that. You see, they paid for the research that created me.

And now, I contribute nothing to society. I pay no taxes, work no jobs. The only decisions I’m allowed to make are restricted to which television program to watch, or which book I want to read. (In case you wondered, I’m not a slow reader. I read quite well, thank-you.)

I live basically in a zoo, except I am the only specimen there, and the zoo keepers all wear lab coats. I suppose the lab coats are designed to protect them were I to spit on them or throw excrement.

I admit, as a child I used to act out with what you consider primitive behavior, throwing feces to vent my anger. I do have tough skin, but no child wants to be continuously poked and needled and questioned. Would you?

But I’ve outgrown that. I’ve learned that when it suits me I can produce a terrifying stare or a teeth-bared snarl that scares the crap out of the more timid researchers. Ah yes, I do enjoy having fun at their expense. It’s about the only thing they can’t control in my otherwise manufactured and manipulated world.

And of course they don’t dare punish or threaten me, because I am, after all,  the rarest person in the universe, the only living Neanderthal.

But about that watermelon?

Having nothing to do of any real value gives me time to think … lots of time. Now, since a part of me is a part of you (genetically that is), I’ve been inclined to wonder why my kind is gone, and you Homo sapiens have become the overlords of the planet, at least for the time being.

And I’ve decided that I am truly a seeded watermelon, and you’re seedless.

The seedless watermelon is very much like the older, and almost extinct seeded variety, but with one subtle difference; it’s infertile. (If this analogy becomes too Freudian for you, just keep your mind on watermelons.) Watermelon is, I sincerely believe, one of God’s gifts to man.

But of course you Homo sapiens weren’t content with that. No, you decided to take advantage of a genetic flaw, a freak watermelon with few if any seeds, that is quite incapable of sustaining itself in the gene pool.

Since spitting out melon seeds is apparently such a difficult proposition for your kind, the seedless variety is overwhelmingly popular. It has crowded out the natural watermelon from grocery stores, so I hear.

Photo Credit: Steve Evans (Watermelons) [CC-BY-2.0 (], via Wikimedia Commons
I’ve been reading about how, based partially on my IQ test results and other research, scientists have decided we weren’t mentally inferior to you. And for sure, as my own testing by the Army has confirmed, we were far stronger.

So what’s not to love?

OK, we are a little shorter, squattier than Homo saps, and from what I hear tall men have a selective breeding advantage over shorter men. So could it be simply a matter of Neanderthal women preferring to breed with you guys,  the new kids on the block, and not with us more vertically-challenged guys? Could that be why my kin disappeared, and why many of you have Neanderthal genes?

I mean, really, could it be that simple; a matter of sexual attraction? Did short-sighted Neanderthal women breed our unique species out of existence?

Well, who would have thought an infertile and obviously biologically deficient watermelon would have replaced the real thing in popularity?

But it has.


















Where Have All the Letters Gone?

By Petar Milošević (Own work) [CC-BY-SA-3.0 (], via Wikimedia Commons
When is the last time you wrote a letter to a family member or loved one?

I’m not talking about email, or text messages; digital communications do not count. I mean a letter on a piece of paper, placed in an envelope with a stamp, and mailed at a mail box or post office; or in a very private way, lovingly slipped underneath someone’s door.

In the hurry up, speak sparingly Twitter generation, there seems to be little value in penning an honest-to-goodness letter. Compared to instant communication, letter writing with an ink-filled pen seems agonizingly slow, sloppy and so twentieth century.

I recently opened a grey metal box that had lain dormant, ignored, for up to 50 years. It was a time capsule, holding remnants of this young man’s life in 1964 and before. In it were letters, letters my Dad had written to me during my college years.

My parents have been gone for many decades now, and reading those letters after such a long time was a joy. Unlike emails and tweets, those letters told a story, a story of how my parents were reacting to and appreciating my new found freedom and expressions of individuality.

My father, a physician who practiced medicine for 50 years, wrote words that are even deeper in meaning now than they seemed at the time. “We are glad that you seek the places that are apart, such as the mountains and the sea,” he wrote. “It is so easy to rush past the beauty and truth of life, especially in this age. An older and wiser one once said, ‘Let us not hurry, not worry, and let us take a moment now and then to smell the flowers along the way.’ ”

And then there were the words I puzzled over briefly before realizing what it meant.  “Their being and meaning will never know the obsolescence of most of that which is taught.”

Frankly, that was a lesson that takes a life-time to understand, for in time we come to know that many things we are taught while young will eventually be found wrong, or at least inaccurate. In other words, so-called truths change.

In 2064, fifty years from now, how will you or your descendants be reminded of things you said, or things your parents and other loved ones thought way back in 2014? How will memories of 2014 be renewed?

Hourglass. By S Sepp (Own work) [GFDL] via Wikimedia Commons
Even now, the concept of writing love letters seems sweet but archaic to those in their twenties. So I wonder, will there be such a thing as love letters in the future?

Facebook posts certainly won’t be preserved for fifty years. In fact, both Facebook and Twitter will be long forgotten, replaced by more culturally relevant trends. And let’s face it, have you ever said anything on Facebook that deserves to be preserved for fifty years?

I suppose that as my father saw his time on earth becoming increasingly limited, he realized that time, the time to enjoy life, was a precious commodity, yet one not well appreciated until the sand in the clock is half run out. That is an important lesson that I, with my own sand ebbing away, have at last come to appreciate. But if I did not have my Father’s letter to read now, fifty years later, it would be a lesson long forgotten.

In a tweeting, Facebook society, how will we hold pages and memories in our hands when our parents and other loved ones are gone?

Sad to say, I don’t think we will.







How Cold Can Scuba Regulators Become?

The Arctic science diving season is in full swing (late May). Starting in September and October, the Austral spring will reach Antarctica and science diving will resume there as well.

Virtually all polar diving is done by open-circuit diving, usually with the use of scuba. Picture046

As has often been reported, regulator free flow and freeze up is an operational hazard for polar divers. However, even locations in the Great Lakes and Canada, reachable by recreational, police and public safety divers, can reach excruciatingly cold temperatures in both salt and fresh water on the bottom.

Sherwood Fail

Decades ago a reputed Canadian study measured temperatures in a scuba regulator, and found that as long as water temperature was 38° F or above, temperatures within the second stage remained above zero.

Recent measurements made on modern high-flow regulators at the U.S. Navy Experimental Diving Unit show that the thermal picture of cold-water diving is far more complex than was understood from the earlier studies.

NEDU instrumented a Sherwood Maximus regulator first and second stage with fast time response thermistors. The regulators were then submerged in 42°, 38°, and 34° F fresh water, and 29° F salt water, and ventilated at a heavy breathing rate (62.5 liters per minute), simulating a hard working diver.

In the following traces, the white traces are temperatures measured within the first stage regulator after depressurization from bottle pressure to intermediate pressure. That site produces the lowest temperatures due to adiabatic expansion. The red tracing was obtained at the inlet to the second stage regulator. The blue tracing was from a thermistor placed at the outlet of the “barrel” valve within the second stage regulator box. Theoretically, that site is exposed to the lowest temperatures within the second stage due to adiabatic expansion from intermediate pressure to ambient or mouth pressure.

Regulators were dived to 198 ft (60.4 meters) and breathed with warm humidified air for 30-minutes at the 62.5 L/min ventilation rate. The regulator was then brought to the surface at a normal ascent rate.

To make the breathing wave forms more distinct, only one minute of the 30-minute bottom time is shown in the following traces, starting at ten minutes.

The first two tracings were at a water temperature of 42° F. In the first tracing, bottle pressure was 2500 psi, and in the second, bottle pressure was 1500 psi. (For all of these photos, click the photo for a larger view.) 42 2500 SM2

Color code

Color coding of thermistor locations, all internal to the regulator.

42 1500 SM2



When bottle pressure was reduced from 2500 psi to 1500 psi, all measured temperatures increased. The temperature at the entrance to the second stage oscillated between 0° and  1°C. At 2500 psi that same location had -1 to -2°C temperature readings.






The next two tracings were taken in 29° F salt water. The coldest temperatures of the test series were in 29° F water with 2500 psi bottle pressure.

29 1500 SM2

29 2500 SM2










As a reminder, 32°F is 0°C,  -22° C is equal to -7.6° F, and -11°C is 12.2°F. At a bottle pressure of 2500 psi, the temperature inside the second stage (blue tracing) never came close to 0° C. So we’re talking serious cold here. No wonder regulators can freeze.

Frozen Reg 1_hide


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This material was presented in condensed form at TekDiveUSA 2014, Miami. (#TekDiveUSA)


Do All Boys Cause Their Mother Grief, or Is It Just Me?

Mother’s Day 2014 has come and gone, but not without my thinking of the grief I caused my ever patient, ever tolerant, and certainly loving Mother.

I think the only time when I didn’t surprise her was when I was born. She always called me “Johnny on the Spot” since I was apparently born on my (or is it her? Make that our…) due date.

I’m sure there was some surprise when I turned out to be a curly headed blond with green eyes … like no one else in the immediate family. Hmmm… But at least there was no grief involved, other than the usual wailing and gnashing of teeth accompanying child birth.

The grief started apparently about the time I became mobile. I was probably the youngest toddler in Fort Smith, Arkansas to try to climb a fence, and break a collar bone in the attempt. What was I thinking? I could barely walk, much less climb?

Fortunately I don’t remember it.

But I do remember my first toddler “run away from home” attempt. I toddled maybe half a block down a hill before my brother caught up with me and led me back home, luring me with the words I still remember: “Mom’s cooking bacon!”  Well then, that’s different!

If only all toddler insurrections could be ended so crisply.

As for collar bones, my first break was not my last. A few years later I broke the other collar bone, an event I do remember well. My Dad, an orthopedic surgeon, was able to put my shoulder in a sling quicker than a quick draw artist could draw a pistol. He was good, and I kept him in practice.

I also acquired an assortment of scars on my left knee which the Army was later pleased to find out about. You know, they wanted to be able to identify my body just in case all that was left of me was my left knee.

I guess having been a rambunctious boy was good for something.

Riding a borrowed bicycle into the back of a parked car was not my brightest move as a child. I knocked myself out cold. When I woke up, I remember telling my Mom “My head hurts.” As much as she wanted to, she could do nothing to ease the pain of my concussion.

Shortly after that, we moved to Texas, where I broke my collar bone again.

After a move to Kansas, Mom and I rode a train to California to visit my much older sister and my Mom’s sisters. On the way, I got motion sick and threw up all over some nice lady’s dress. I was too sick to be embarrassed, but my poor suffering Mom had to endure yet another indignity forced upon her by her woe-begotten son.

I’m sure she was wondering why God had blessed her with a fourth child so late in her child bearing years (yes, I was involved in an accident even at my conception). About the time she took a nap and I disappeared into the California desert wilderness, she must have been thinking how much nicer three kids would have been rather than four. She thought I was lost in the desert, but I knew where I was. I saw a snow-covered mountain in the distance and thought it would be cool to walk to it in the 120° heat, just to play in the snow.

A kid raised in flatlands has no sense of distance, because I now know that from where I left the travel trailer at Palm Springs the nearest tall mountain is a distance of at least 50 miles. After covering maybe a half a mile over rocky desert hills, my half baked brain realized that perhaps snow was out of reach.

That Mom and half the residents of the trailer park were searching for me did not occur to my 5th grade brain until I crested the closest ridge and heard men on the desert floor calling for me. She of course was frantic, and then relieved, and I was glad to get back out of the parching sun.

She was no doubt wondering if her last of four kids would be the death of her.

Later that year I got knocked out again, at school (5th grade boys can be rough) but I could tell Mom and Dad were becoming desensitized to my traumatic injuries. I always seemed to bounce back just fine.

Now that I think about it, my early adult years were only a little less disturbing for Mom. There was the time in graduate school when I was simultaneously knocked out, yet again, and had yet another bone broken; my jaw this time — I never saw the hit coming.  Of course Mom, who was far away at the time, could do nothing but worry about her son’s proclivity for repeated injuries.

Perhaps I was suffering a little from repeated Traumatic Brain Injury when I decided to ride a 50 cc Honda home to Kansas from Atlanta, without telling the folks how I was getting home. Poor Mom got a migraine out of that escapade, but I almost made the distance before burning up the little engine.

I think I now understand the meaning of “long suffering.”

Shortly after she passed away from a surgical misadventure, I found myself on a beach, with my first airplane, trying to figure out how I was going to get out of this pickle. So I decided to talk to her. I found it comforting.

But just now I’m imagining what she was thinking when her spiritual duties were interrupted by a call from her troublesome boy.

“Oh, it’s you again. What have you done to yourself now?”

After I confessed my predicament, she probably said (but I can’t swear to it), “I feel another migraine coming on.”


Happy belated Mother’s Day Mom! I didn’t mean to be such a pain in the neck; it just comes naturally to some people. But I do love you!






What Is That Music?

The mark of great music is that you will always remember where you were and what you were doing when you first heard it.

In early 1977 I was a young First Lieutenant in the Army, training at Aberdeen Proving Ground, Maryland. I had flown up there to attend 3-months of Active Duty for Training. It was winter, but on one weekend when the weather promised to be beautiful, several of us piled into a car and headed South to Washington, DC. None of us had been to DC before, so the trip was one of discovery and high expectations. Smithsonian_Air_and_Space_Museum

For a space and aviation enthusiast like myself, the long-anticipated highlight of the trip was the chance to see the newly opened Smithsonian Air and Space Museum, and to see my first Imax movie, which happened to be “To Fly”.

In the dim light of the large sloping theater, we waited for the movie to begin. Meanwhile, music was softly playing.

You know how when you’re at a restaurant or bar and someone is playing, you’re not necessarily aware of the music per se. It’s just part of the ambiance, the background. But as that music began, it started with deep strings, rhythmically, methodically stroking through the music.

Deep bass notes have always thrilled me. I am a player of clarinets, which have no bass properties to speak of, so perhaps it is the novelty of bass that so captures my imagination. And so it had slowly begun to work on me, that anonymous music.

It was clearly classical, most likely some well orchestrated version of what must have originally been chamber music. As I listened ever more attentively, the music built on itself  and added complexity which maintained and then grew my interest. I had never heard it before, and neither had my friends, but I began questioning myself, “What is this music?”

Crop 1
Excerpt in the key of D

After over four minutes, when you would think the pace and melody would be becoming somewhat worn, the composer threw in some accidentals, which frankly shocked me, as they must have the music’s first listeners. There was a string of four eighth notes, and one of them sounded flat, while its pairing just two notes away was not. What is this, I thought? And then in the next measure it was repeated, so it certainly wasn’t a mistake. It was an intentional musical device, and one that I loved for its novelty.

It was as if the composer had been holding back for that subtle surprise until near the end of the piece. Just as you thought you knew what to expect, something new appeared in the melody.

Strangely, I left that theater thinking as much about that mysterious theatrical prelude as about the movie. And for an aviation enthusiast, that’s saying a lot.

Before long, I began to hear that piece elsewhere, and with increasing frequency. In fact, the music enjoyed a burst of popularity starting in the early 1970s, the same period when I first heard it.

If you haven’t guessed by now, I’m talking about Johann Pachelbel’s Canon in D. It is now so well known that it has its own web site. The following video featuring Canon in D was compiled by “diemauerdk”.


According to the Internet, Canon in D first became available to the masses through a 1970 recording, reportedly by the French musician Jean-Francois Paillard. Oddly, even though it was written in about 1680, it was not published until 1919. I have no doubt that its rise in popularity was due in no small part to the large audiences exposed in the iMax theater at the Smithsonian Air and Space Museum. The fact that it was the main theme of the 1980 popular movie, Ordinary People, only helped to propel it to mainstream consciousness.

On viewing the piano sheet music it’s easy to spot where the usual C#  F# structure of the key of D is flatted to produce an appealing effect. The four notes of note, if you will, are D Cnatural B C#. To an ear accustomed to hearing C# throughout most of the piece, a Cnatural sounds flat; but in a delightfully unexpected way.

Crop 2





I consider myself lucky to be one of the first Americans to hear what was to me new music, and to appreciate that it was a very special work indeed. However, I must wonder; three hundred years from now, do you think any works from present day artists will be “discovered”, and enjoy an almost universal popularity?



Nightmarish Thoughts of Being Eaten

DSCN1233aThere is a downside to situational awareness.

I discovered this fact while 868 miles north of the Arctic circle, 600 miles south of the North Pole. It took place in Ny-Ålesund, Svalbard, a part of the well-known island Spitsbergen. 

I was helping the Smithsonian Institution train divers in polar diving. My job was to teach them about scuba regulator performance in frigid water.

A fact of life in Ny-Ålesund, the most northern continuously occupied settlement, a research village, is that Polar Bears are always a threat. In fact, one came through town during our visit to Svalbard.  The Greenland sled dogs, tied down outside, were understandably, and quite noisily, upset. The bear walked right past them.


After the excitement of that nighttime polar bear prowl had begun to wane, the incident remained as a not so subtle reminder during seemingly routine activities. For you see, polar bears are emotionless killers; to them, we are prey. Tracking and eating a human gives it no more pause than us picking blackberries alongside the road. For adult polar bears, humans are simply a conveniently-sized food item, not nearly so fast and wily as their typically more available meals, seals.

Unlike the ploy of divers bumping potentially predatory sharks on the nose to dissuade them from biting, bumps on the nose don’t work with polar bears. Without a gun by your side, a walk in Svalbard is a walk on the wild side, and not in a good way.

2007-03-1505-59-59_0077I was observing and photographing boat-based diving operations from the end of a long pier jutting 375 feet (115 m) into the Kongsfjorden. Normally in March the fjord is ice covered, but the year I was there (2007) there was no ice to be seen except at the nearby glacier.

DSCN1307 crop

I had been standing at the pier’s end for a while taking photographs, and soaking up the polar ambiance, when I looked back and realized that from a safety standpoint, I was vulnerable. That is when situational awareness began to kick in. 

We were in a deserted, industrial portion of the town. The old coal mining operations were shut down long ago. Other than the divers on and in the water, I was the only one around. And I was stuck out on the end of a very long pier, with no means of escape.

If an intruding and hungry bear made its appearance at the land side of the pier, I would be trapped. Although I was dressed for cold, I was not dressed for cold water. That water was, after all, ice water. Polar bears, on the other hand, are excellent swimmers in polar water. So after I’d jumped into the water, which I would have if faced with no alternative, it would have taken the bear only a few furry strokes before he would have me. While he or she would find my body parts chilled on the outside, my internals would still be pleasantly warm as they slid down its gullet.Me cropped

Being a sensible person, I called the boat drivers over and put them on alert; should a polar bear appear at the far, land-side end of the pier, they should pick me up post haste. Otherwise, there would be no way I could safely escape from my vulnerable position. No photograph is worth dying for. 


DSCN1311 crop

Being nice fellows, they agreed they would keep an ear out for my shouts. They then returned to their duty of waiting for and recovering the divers.













As the boat eventually sped off with its load of thoroughly chilled divers, I realized that I had been deluding myself all along. At their distance and with the noisy interference of the boat motor, my shouts would have been inaudible. And from their low position on the water, they would have been unable to see what I was so agitated about; until it was too late.

DSCN1325 crop

My return back to the safety of the diving center was a cautious one; with the full realization that I was exposed and vulnerable for the entire route. Fortunately, safety was only a third of a mile away, but that was a long 500 meters, which gave my alert mind plenty of time to focus on walking quietly, and avoiding being eaten.

Nothing focuses the mind like knowing that close by, hidden by piles of snow, could be lurking a camouflaged predator looking for lunch.




This Youtube video shows a Polar Bear searching for food in Ny-Ålesund during the brief Arctic summer.



Half Magic

1033282 Long before J. K. Rowling began writing the wildly popular Harry Potter series of books on children and magic, Edward Eager wrote a similar themed book in the 1950s. In my child’s mind at that time, Eager’s book, Half Magic, was one of the most remarkable and memorable books I’d ever read. In fact, it is currently rated by some as #54 among the top 100 children’s books.

The fact that it was featured in our elementary school’s library did nothing to detract from the read. After all, that was the joy of school libraries — the ability to browse through the rows of books waiting for discovery.

There was another library book I remember, about a barnstorming pilot who for one reason or another kept crashing, and yet somehow surviving. It was exciting reading, and surprisingly did not deter me from my love of flying. But I digress.

Thanks to the magic of the Internet, I was able to identify Half Magic and download it, and read it. Presto, change-o, just like that!

But, it’s not at all what I remembered.

Here’s the thing about memory; it is ever so malleable, especially in children. All I really remembered in my teenage and adult years was that there was something in it about people who were half white and half black. Frankly I’d forgotten the whole magic theme.

What had colored my memory was the power of a vivid image found on the cover of that book, and the fact that it was popular during a time when racial integration was a frequent topic in the news. Somehow, those mental bits merged into what I believed the book to be. Many years after reading it I had the curious impression that it was a morality play of sorts, where people were in fact half black and half white.

Well, if that happened, racial profiling would be nonexistent, wouldn’t it? If you were of mixed race, with your body literally halved by distinct racial characteristics, then you obviously couldn’t be bigoted. And for that reason I held that book in high esteem. But due to my fragmented memory, I despaired of ever finding it again.

And then there was Google. While I may razz Google a bit for their intrusiveness, I do consider it a blessing to be able to Google the words “half black and half white” and see before me a panoply of related images. There, buried in the search results, was the image of a book cover that I instantly recognized from so long ago.

I had no conscious memory of it, but yet I recognized it among all the other less relevant images. (Yes, there really is such a thing as  subconsciousness, just in case you wondered.)

Happily, the 50th anniversary edition of that book was recently published, so the book is available for another generation of young minds looking for magic with a moral. And indeed, it really is a morality play of sorts. But sadly, someone felt the need to modernize the cover, which is now far more visually complex. But I wonder; is it memorable? HalfMagic

If I had a book cover, I’d want that cover to be memorable enough to transcend the decades, and jump out of my seemingly inaccessible memory like a Jack-in-the-Box long after all other memories of the book had faded.

I am patiently waiting for my 6-year old grandchild to be still long enough to let me read her this book. As for the rest of you, real childhood magic as portrayed in Half Magic may not be as fantastical as Harry Potter, Hogwarts School, and the dark Lord Voldemort, but it seems a lot more believable.

For more information on this memorable book:


The Tragicomic Consequences of Bad Timing

They say that in comedy, timing is everything. Well, on this day my timing was badly off.

My older brother and I in Ft. Smith, Arkansas. I still remember those cowboy boots.

My brother was born five years before me, and of my siblings was the one with the most direct interaction with me as I was growing up. We shared life experiences, and apparently we shared the same quirky humor; the type that finds humor in everything, even dark moments.

I once visited him when he lived in New Orleans. During that visit he delivered a long and hilarious series of stories, most of them with a beautifully affected Cajun accent, à la Justin Wilson.

One story in particular captured my imagination, but was of unknown authorship. It started with “Here’s the story of Foot, Foot Foot and Foot Foot Foot”. The story itself had been lost from my memory, but that lead-in line was never forgotten. Decades later my brother could not remember the story either, try as he might.

Last fall I was with my brother again and I was madly searching on my phone for all the Justin Wilson jokes I could find, and sharing them with him. I was reliving some wonderful times together, even though he didn’t respond. But I knew he was smiling inside. 

You see, my last surviving sibling was in hospice, and it was approaching the time for him to “slip the surly bonds of earth” as John Gillespie MaGee said so eloquently in his poem High Flight. (My brother was one of the three Clarke boys who were all pilots).

Then I thought to search the Internet for “Foot Foot Foot”.

By Monique Haen (Own work) [CC-BY-SA-3.0 (], via Wikimedia Commons
When I located the following, I read every word for the first time. In music they call this “sight reading”, and sight reading can often lead to surprises. This reading was no exception.

I started reading out-loud as I scrolled down through the text on my cell phone. I was so excited to finally find the story. 

“One fine summer day, three rabbits named Foot, Foot Foot, and Foot Foot Foot were sitting in their rabbit den. Foot Foot Foot and Foot Foot were big rabbits and Foot was a little youngster. 

Foot Foot said, “I’m hungry!”

“So are we,” said Foot and Foot Foot Foot.

(For full effect, this story really needs to be read out-loud, just as I was doing.)

Foot Foot said, “Foot Foot Foot and I can hop over to Farmer Brown’s cabbage patch. After we eat, we can bring some back for you, Foot.”

Little Foot stamped his little foot and said, “But I don’t want to stay here!”

“Foot,” said Foot Foot Foot, “Don’t make me put my foot down. You know that Foot Foot and I are bigger and faster and we can get away from Farmer Brown.”

So Foot Foot and Foot Foot Foot hopped over to Farmer Brown’s garden and started munching away on the delicious cabbage.

All of a sudden there was a noise and Foot Foot and Foot Foot Foot ran and hid, thinking it was Farmer Brown with his shotgun coming to get them.

“It’s just me!” said Foot, surprising Foot Foot and Foot Foot Foot.

“Foot, you are a very bad little rabbit,” said Foot Foot Foot. “You know Foot Foot and I told you to stay home.”

“I know,” said Foot, “but I said to myself, ‘I should go join my brothers Foot Foot Foot and Foot Foot and eat the cabbage too.’ “

“Well,” said Foot Foot to Foot Foot Foot, “Since he’s already here, Foot might as well stay.”

So Foot, Foot Foot, and Foot Foot Foot again started munching happily away on the cabbage.

Then Foot Foot Foot heard a loud foot fall. “I see you rabbits! And this time I’ll get you for sure!” yelled Farmer Brown.

By this time I was reading to my brother as fast as I could scroll down on the little screen.

“Foot Foot Foot yelled to Foot Foot and Foot, “Run for your lives Foot Foot and Foot!” as he scrambled back towards the rabbit den.

Now since Foot Foot and Foot Foot Foot were the older and faster rabbits, they made it back to the den before Foot did. Just before Foot reached the den, BLAM!! roared the shotgun.

After a bit, Foot Foot and Foot Foot Foot looked outside. To their sorrow, there was poor Foot, shot dead by Farmer Brown.

Foot Foot looked at Foot Foot Foot and said, “We can’t just leave Foot there, Foot Foot Foot.”

“Quite right Foot Foot,” agreed Foot Foot Foot. “Let’s give Foot a proper rabbit burial.”

So Foot Foot Foot and Foot Foot dragged little Foot to his favorite spot in the meadow and started digging.

They were almost done covering Foot up when Foot Foot looked up at Foot Foot Foot and said, “All this work has made me hungry again. Come on Foot Foot Foot, let’s go back to the garden and eat more cabbage.”

Then I scrolled down to the last line; I was really excited by now.

“Foot Foot are you crazy?” exclaimed Foot Foot Foot. “Can’t you see that we already have one Foot in the grave?”

No sooner had I read that punch line than I gasped. I couldn’t believe I’d just said that, out-loud. My brother did have, at that very moment, one foot in the grave.

But then I was graced with a mental image of my brother rolling his eyes, smiling, and saying “John, you’re such a doofas! Your timing really sucks.”

Yes, I did accidentally have lousy timing, I admit, but I can laugh about it, as I imagine he did as well, somewhere deep inside. You see, that’s what brothers do.

And what better way to share the worst of times than by sharing the best of times.





Root Causes: Some Accidents Are No Accident

Interesting flights and interesting dives provide an opportunity for post-event introspection; debriefing if you will.

Professionally, I am called upon to analyze fatalities and near-misses for the Navy and, occasionally, the Air Force. Personally, I spend even more time analyzing “what ifs” for my own activities.

For example, recently I was preparing a video of one of my more beautiful nighttime flights with a passenger, departing the coal-mining regions of Pennsylvania, heading south over the valleys and mountains of Appalachia as the early morning sun began to brighten our part of the world. Sunrise crop