Margin of Safety

A diver’s breathing equipment, helmet, gas bottle, umbilicals and buoyancy compensator lie stretched out on the grey concrete floor.  The diving gear has a look of sadness about it. Perhaps that equipment will tell a story of why its owner is dead, but usually it does not.

Storm clouds from 30,000 ft. Photo by Wendell Hull.

In another part of the world the NTSB catalogs the fragments of an airplane shredded by the elements and thrown in a heap back to earth. The only good thing to come from an aircraft accident is that usually there are enough clues from wreckage, radio recordings, radar returns and weather reports to piece together a story of the end of life for pilot and passengers.

It’s always the question of “Why?” that drives any investigation.

Perhaps it is the knowing of how death comes, so unexpectedly to surprised souls, that makes it just a little bit easier to make the mental and emotional connection between an interesting moment and a deadly moment. If that is true, and I believe it is, then the telling of such macabre stories can be justified. It is not a telling through morbid interest, but a sincere belief that by examining death closely enough we can somehow force it to keep its distance.

That may be foolish thinking, but humankind seems to have a hunger for it, that esoteric knowledge, so perhaps it is a truism. Perhaps we sense instinctively that the knowing of something makes it less fearsome.

Being a student of diving and diving accidents, I know full well how unexpected events can make you question what is real and what is not, what is normal and what is abnormal. Without practiced calm and reasoning, unexpected events can induce panic, and underwater, panic often leads to death. That is also true for aviation.

The best preventative for panic is a realistic assessment of risk. Risks are additive. For instance, flying in the clouds is accompanied by a slight degree of risk, but with a properly maintained airplane, with a judicious use of backup instruments and power supplies, and with recent and effective training, that risk can be managed. In fact, I delight in flying in clouds; it is never boring, and I know that I am far safer than if I had been driving on two lane roads where the potential for death passes scant feet away every few seconds.

Flying at night is another risk. If something were to go terribly wrong, finding a safe place to land becomes a gamble. On the other hand, seeing and avoiding aircraft at night is simple because of the brilliant strobe lighting which festoons most aircraft. For me, the beauty, peace and calm air of night flight makes it well worth the slight risk.

Garmin NEXRAD Weather display.

Technology has made weather flying safer and, I have to admit, more enjoyable. The combination of GPS driven maps and NEXRAD weather has made it almost impossible to blunder into truly bad weather. During the daytime, my so-called eyeball radar helps to confirm visually what NEXRAD is painting in front of me. If it looks threatening, it probably is.

Unlike aircraft weather radar, virtually every pilot can afford to have NEXRAD weather in the cockpit. And unlike aviation radar, NEXRAD can see behind storms to show the view 100 miles downrange, or more. Having often flown in stormy weather without benefit of NEXRAD,  I truly rejoice in the benefits of that technology.

WX 900 Stormscope

I routinely fly with not only NEXRAD, but also a “Storm Scope” that shows me in real time where lightning is ionizing the sky. Those ozone-laced areas are off-limits to wise aviators. But sometimes even a Storm Scope is not enough to keep the willies, or as some call it, your spidey sense, from striking. (Presumably spiders are not particularly cerebral, but they are pretty adept at surviving, at least as a genus and species.)

I was recently flying around stormy weather, carefully avoiding the worst of it, and maneuvered into a position that would provide a straight shot home with yellow tints showing on the weather screen, suggesting at most light to moderate precipitation. I had flown that sort of weather many times; it usually held just enough rain to wet the windshield.

However, my internal risk computer made note of the following factors: we were in the clouds so if weather worsened I wouldn’t see it. Night was approaching which markedly darkened the wet skies we were beginning to enter.  The clouds and darkness conspired to make useless my eyeball radar. In addition, the Storm Scope was unusually ambiguous at that moment. I thought it was confirming a safe passage home, but I could not be 100% certain.

On top of that, the FAA recently warned that NEXRAD signals can be considerably more delayed than indicated on the weather display. The device might say the data is 2 min old, but the actual delay could be 10 minutes or more. In other words, the displayed image could be hiding the truth.

Aircraft weather radar.

Planes have been lost because of untimely NEXRAD data. For that reason there is a philosophical difference between NEXRAD and true radar. On board weather radar is said to be a tactical weather penetration aid, and NEXRAD is a strategic avoidance asset. My gut told me that at that moment in airspace and time the boundaries between those two uses, tactical and strategic, were getting fuzzy.

It is times like that when an awareness of the slim margin between a safe flight or dive, and a deadly flight or dive, becomes a survival tool. In this case, I and many other experienced pilots have made the call to turn around and land. Unfortunately, the record and the landscape is littered with the wreckage of those who chose otherwise.

They forgot just how thin the margin of safety can be.

The flight (green line) from Cobb County Regional (KRYY) to Panama City (KECP) was interrupted by a stop at Montgomery AL.









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