Wednesday, November 16, 2011

Tapestry of Disaster - An Aviation Accident Story


Often, in his most reflective moments, he would extol the many virtues of flying; the splendor of sights, of new places but mostly of its freedom.  He was 60 on his last birthday, a Vietnam veteran with an artificial leg flying with a 2nd class medical certificate and a Statement of Demonstrated Ability (SODA).
He flew with precision, dedicated to his hobby and mode of transportation.  Every flight was enriching to him.  He carried his task of flying with zeal, from checklist to checklist, double-checking while motoring one to two miles above terra firma.
Soon that cold, rainy night in October, when I got the news of his plane crash, it scared me, then chilled me, and finally numbed me.  He was, in my mind, going to be an old pilot, for he was never bold.  He flew this immaculately dressed Mooney 201.  But the crashed plane was a Cherokee Six.
He apparently flew it with the gust locks still attached!
The plane had taken-off, gained 500 feet and then, predictably, plowed into the woods.  This man, in life a stickler for checklists, in death was now the object of a storm of controversy and was leaving a legacy of stuff that he would not have been proud of.
They tried to piece together the shattered dreams of his mind and the associated features of the ill-fated flight on that chilled rainy night in October. 'Accidents don't just happen,' said the aviation counselor from the FAA, 'Planes don't just fall out of the sky.'  There is some truth to this, if you were to evaluate the cumulative vapor trail that eventually condenses into the big splash, multiplicity of factors have been involved.
Let's look at the so-called 10-17 percent catastrophic engine failures in piston aircraft.  I am not a betting man, but I can wager that most, or all of them, gave plenty of warning signals and hence, could have been averted.  The gremlins may have shown up in a previous flight, in the pre-flight, or in the intuitive feel.  The oil analysis may have revealed the chewed metal in the filter, maybe the need for more oil, a blob of oil on the ground, or discordant magnetos.  In flight, it may have been a change of the aircraft's behavior, in its speed, sound, dynamics, the hum, and all of the subtle noises that we are attuned to in the cockpit.  This subtle vapor trail of metal, sound, feel, and dynamics is there for us to recognize.

When we commit an error it is generally an isolated one, and we get away with it.  This 'getting away' mentality, unfortunately, reinforces the behavior as being okay - it sets up a confirmation bias. But start stitching a series of these scenarios together, and a tapestry of disaster unfolds.
Imagine a series of cards with random holes in it reflecting the error-prone deficiencies of human beings.  Each little hole reflects an act of omission or commission (failing to check the trim, or the fuel quantity, and so on; you get the point).  Once in an unfortunate while, when those holes line up in sequence, an accident occurs.

The first priority to safety remains trying to patch the holes in each of those successive cards.  Learning the art of flying, practicing it, constructing a practical checklist for all possibilities, and never taking flying for granted.  For instance, every time before I fly into an airport, I look at its layout to see on departure where a straight-in engine out on take-off or landing would save my bacon.  Not much but it keeps your guard up.

Consider the big boys who dream of flying Mooney's but are stuck with the Boeings.  They, too, can have a bad day.  The flapless take-off in Detroit, Michigan, led to hundreds dead - a minor mistake that led to a major tragedy.  A Continental aircraft was about to land gear-up at the Newark airport until advised by an American pilot on the ground to put the wheels down.  Mistakes from shoddy cockpit behavior, taking things for granted, or having the attitude that 'I am the greatest' will bite.

Flying in low overcast without the prerequisite experience or attempting a crosswind landing beyond your abilities speaks volumes of the male gender.  Some of the newly minted and even long-time pilots with little weather experience who venture into the gray unknown of an overcast day just for a rush or, better, stupidity.  How can you justify that with anything but the remark, 'idiots?'
The former is not flying with adequate charts, plates, or lack of their utility, etc.  The latter is when your instinct tells you, 'It is not good to go even on severe clear and a million,' so heed it.
There are preconditions for these unsafe acts [as per the Office of Aerospace Medicine's technical report, The Human Factors Analysis and Classification System (Shappell & Wiegmann, 2000)]:

  • Substandard Conditions of Operators
  • Adverse mental states
  • Psychological states
  • Physical and mental limitations
  • Substandard Practices of Operators
  • Cockpit Resource Management and Personal Readiness
Now, I'll get back to the story.  My veteran aviator would occasionally drink beer but cognizant of the regulations, he would wait eight hours before flying.  He mostly flew his Mooney, where his checklist was always dangling from the mixture control knob and he never allowed himself to rush.
On that fateful night, our 60 year-old pilot had consumed alcohol nine hours before, but he also had taken an over-the-counter medication for allergies, which it turns out, decreases the alcohol metabolism in the body (slows the breakdown of alcohol, hence the effects of alcohol are prolonged in the body).  He was flying an aircraft that he was not totally familiar with, and all his tell-tale readiness checklists were not present to help him where they usually presented themselves before flight, and he was in a rush to pick up his friend from an airport only 20 miles away before a line of thunderstorms came through (that friend owned the Cherokee).
A careful, analytic mind reduced in alacrity, unencumbered by the weight of his previous knowledge through the harmful effect of persistent alcohol in his body, failed to see the cues of impending disaster.  Having found none of the patterned elements that had kept him safe for 60 years, 4 months and 3 days, his clouded brain edged him on that evening and sought to play its own game of chance.
There are many lessons to learn from this story.  My own guidelines are as follows; add on to them as you please:
  • Know your limits
  • Observe those limits
  • Develop good habits - use checklists
  • Follow those habits
  • Rectify a 'getting away' scenario; do not amplify it
  • Be constructively critical of each flight
  • Even the best pilots make mistakes - minimize the number and break the chain
  • Always think about where is the possible error
  • If intuition tells you something is wrong, prove the intuition to be wrong before proceeding.  Intuition is mostly right (Intuition arises from more then your six senses. It originates from the plethora of sensory input including skin, joints, muscles etc) - Read the book "User Illusion."
  • Alcohol, with or without medicines, is dangerous - Affects the brain function directly through euphoria (I can do anything) and then depression (head in the toilet bowl).
  • Ground yourself voluntarily if you need to for any medical reason.  Death is not an option.
  • Improve technique; periodically practice safe flight with an instructor - Proficiency is the name of the game - gives you clarity of purpose and a skill set to achieve it.
  • If flying a different aircraft, become thoroughly familiarized with it before flight
  • Do not violate the rules; they are the products of previous tragedies!

Good decisions are born of good judgments, and good judgments are born of prepared, rested, and alert minds.  Fly safe - always.

Published previously in FAA Aviation News  and Federal Air Surgeon's Bulletin

1 comment:

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