Sunday, July 14, 2013
Let's Try Looking At The Forest Instead Of The Trees
I have really struggled this week to organize my thoughts on the Asiana 777 tragedy at SFO last Saturday. Sadness with the loss of life of course, was my first reaction. I was awed at the scenes from amateur video showing the evacuation where lives were saved as well as lost. I am frustrated that once again, experienced professional airmen with the best intentions were unable to prevent this accident.
The NTSB team that is investigating this accident will determine the factors, the set of threats if you will, that led to this fatal, hull loss. They ultimately will determine the probable cause and contributing factors. We do know that the aircraft was in an undesired state from which the crew could not or did not recover, but that is just the starting point.
It has been said that there are three crucial points in the evolution of an accident. They are the point at which an accident becomes possible, the point when an accident becomes probable and then the point where an accident is inevitable. Avoidance or recovery by the crew is possible, but becomes increasingly more difficult until the third point is reached.
The analysis of approach and landing accidents resulting in a runway excursion has shown that unstable approaches are a major contributing factor. In a majority of these accidents, absence of a go around or missed approach was the point at which probable became inevitable.
It is far too early in the investigation of Asiana 214 to discuss or speculate what factors, i.e. threats and errors, contributed to the accident. It is certainly appropriate, however, to discuss the psychological factors that go into the critical decision to execute or not execute a go around.
The psychology of a go around is a profound and complex topic. It would appear to be very simple, particularly in light of the fact that most operators and regulators have very clear procedural guidance on the continuation of an unstable approach. Why then, do the statistics show that only a small number of unstable approaches by scheduled carriers result in a go around? FOQA (Flight Ops Quality Assurance) recorders, LOSA (Line Operational Safety Audit) observers as well as anecdotal data all confirm the same paradigm. Airline pilots fly very few (far less than 5%) approaches that would be classified as unstable. However, of that small number of unstable approaches, very few go-arounds are performed. It is this conundrum that defines the psychology of a go around.
Why is the continuation of an unstable approach to a landing such a common occurrence? The same pilots who land out of an unstable approach would never consider continuing below a decision altitude on an instrument approach. Years ago one would occasionally come across a “cowboy pilot” that would duck under, but I haven’t heard of that in many years. Why do pilots treat the bottom line or decision altitude on an instrument approach differently than the stabilized bottom line, usually 500’ AGL, on a visual approach? Is it because we have not “given ourselves emotional permission” to go around? Is it just a matter of ego or saving face? Is it the same mental process that allows drivers to be ok with talking on a mobile phone because they have “gotten away” with it in the past? Is it because pilots see their immediate and specific goal as landing vs. the general objective of maintaining a safe operation? Is it because the crew does not think a go around is necessary at that point to remain safe?
I am not a psychologist and I struggle to completely resolve these questions in my own mind. I could not begin to answer them for anyone else or the pilot population as a whole. I wonder what would be the effect of making a go around the default termination of a visual approach like that of an approach in instrument conditions. We are always emotionally prepared as well as mentally committed to a missed approach in low visibility. Why can’t we be as prepared and committed to a go around on a visual approach?
Accident investigation data has shown that policy and procedure alone are not adequate to address this perplexing issue. The data has also shown that non-compliance is seldom an overt act, but rather the result of some distraction or other operational threat. In fact, sometimes the rigid or compulsive pursuit of procedural compliance becomes the distraction. It’s the classic case of getting lost in the forest because of all the trees. The points where an accident or incident progresses from possible to probable to inevitable are not objective, but rather exist subjectively in the mindset of the crew.
Are we, individually and collectively, prepared and committed to execute an unnecessary go around to avoid the point where probable becomes inevitable?