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Thursday, September 15, 2011

Does This Make Sense ?




I never noticed this interesting conundrum until it was recently pointed out to me. There are Braille markings on drive up ATMs.  Does this make sense?  Just as absurd, I have always wondered why are there handicap parking spots at Sonic Drive In.  You couldn’t walk in and buy a cheeseburger if you wanted to.   These are just a few examples of the paradox that is created when a myopic perspective is used to universally implement regulatory policy and procedure.  It is surprising how many things we take for granted that just don’t make sense when we really think about them. 

Accident prevention is an oxymoron that applies to aviation.  Mishaps can be prevented, bad decisions can be avoided, but not accidents.    “Accident” is defined as an event that happens unexpectedly and did not have a cause or intended plan.  Accidents are bad luck, not mistakes.   I am not arguing that plane crashes are an objective of deliberate intention by the crew.  At the same time, however, most crashes are the result of a lack of a deliberate plan to avoid them.  Human initiated mishaps occur every day.  True accidents are fortunately quite rare.

Stephen Barlay stated in the introduction of his 1990 dissertation on airline disasters, The Final Call , “There are no new types of air crashes – only people with short memories.  Every accident has its own forerunners, and every one happens either because somebody did not know where to draw the vital dividing line between the unforeseen and the unforeseeable or because well-meaning people deemed the risk acceptable.”

No airline crew ever departs with an objective or outcome in mind other than a safe operation and a successful flight.  All flights do not result in a successful outcome however.  Somewhere on that very, very small number of unsuccessful flights, somewhere between departure and arrival, Mr. Barlay’s prophecy creeps in.  If I, or anyone, could explain that anomaly thousands of lives could be saved.  One thing I do know is that victory over unmanaged human error can only be achieved one flight at a time.  A quote by Gerry Bruggink referenced in Final Call very perceptibly describes the root of all pilot error, especially with respect to multi pilot crews,  “uncritical acceptance of easily verifiable assumptions”.

Pilots specifically and the aviation industry in general have a lexicon that is ripe for misinterpretation.  Comedians have exploited the aviation malapropism “near miss” in their routines for years.  It’s funny because the audience understands the contradiction.  Here are two aviation terms that beg for an serious explanation when there is none. Wind shear takeoff and night visual approach.

Wind shear takeoff is the one that confuses me the most.  I have said this before, “Takeoffs are 100% voluntary.”   Why would a pilot or crew knowingly takeoff into conditions that include or are likely to produce wind shear?  Some aircraft flight manuals, when discussing wind shear, actually contain statements like, “If after careful consideration, takeoff is attempted the following performance enhancements should be used.” And the manual goes on to suggest things like a higher takeoff speed, lower flap setting and extra thrust from the engines.  Are they really serious?  The most effective configuration for an airplane when wind shear conditions exist or are expected is with the parking brake set.

Night visual approach is another oxymoron.  Does this one really need an explanation?   Night visual approaches are conducted all the time though.  Why?  Is it more convenient?  Is it easier?  Is it necessary?  Or is it that, as Mr. Barlay writes in Final Call, “Well-meaning people deemed the risk acceptable”?  Data supports that far too often airline pilots come close to terrain and obstacles during these “night visual” approaches.  Can we quantify “too often” in this context?  How does “ever” sound? 

When the goal is a safe operation, how do we rationalize a wind shear takeoff or, even in areas without hazardous terrain, a night visual approach?   Have we become too complacent, too dependent on enhanced flight directors and ground proximity warning systems?  Maybe some wind shear is not hazardous?  Pardon the pun, but maybe we just don’t see night visual approaches as risky.  Why are they not perceived as risky?  Maybe, like the handicapped spot at Sonic, we just take them for granted.

I just thought of one more aviation oxymoron, “acceptable risk”.

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