The Asiana Crash and Swiss Cheese

     After any airline incident, especially a crash, I am always asked by anyone who knows or finds out what I do for a living about what happened, as if my insight into flying would provide some magic answer.  I am certain that every airline pilot gets asked the same thing.
The bottom line is that you know as much about what happened as I do and I can only speculate as to what happened.  I won't necessarily divulge what my thoughts are.  Also, I will be the last person to throw another pilot under the bus.  There, but for the grace of God go I, I often say.
     As a Navy trained Aviation Safety Officer, I was taught to look at facts with no preconceived notions or agendas.  The facts of this incident are not all known.  They will be eventually.  They have an abundance of resources.  The crew survived, most of the passengers survived and the bulk of the aircraft is available for investigation, unlike the Air France Airbus lost tin the south Atlantic.
     So when I hear people telling me what they think happened, I ask them if they are pilots.  Usually they are not, so I ask them how they are deriving their opinions.  I get some very interesting responses.  Until the investigation is complete and published we really won't know why or how.  In the past, these things were done quietly without public disclosure until it was complete.  Now, there are press conferences detailing every aspect and discovery as a result of the investigation.   Pundits and talking heads all begin to formulate the why and how.  In Naval Aviation, "mishaps," (as they were called) were investigated in relative secrecy.  It wasn't until the "Mishap Report" was published that the investigative board's conclusions were published.  If there was an apparent failure of some part or procedure, typically these things would be scrutinized and airplanes would be immediately grounded or a procedure quickly modified as a result of certain obvious discoveries.
     What I do know is this:  regardless of what and how an accident happened, it will always be the pilot's fault; "pilot error."  Ultimately it comes down to the pilot and his or her ability to fly a good plane correctly or a bad plane safely.  
      It is important to know that pilots, even though they are supposed to be "in control," are often out of control of a lot of things that they rely on.  It is vital that others do their jobs correctly and attentively in order for them to be successful.  Flying and operating an airliner is part of a system that has many checks and balances.  Just as in Naval Aviation (and Air Force too, though I can only speak from my experience), there is a support system for pilots operating aircraft, there is a support system for airline pilots.
     In the safety world, we talk about the "swiss cheese" model.  The Swiss Cheese model of accident causation is a model used in the risk analysis and risk management of human systems, commonly aviation, engineering, and healthcare. It likens human systems to multiple slices of swiss cheese, stacked together, side by side. It was originally propounded by Dante Orlandella and James T. Reason of the University of Manchester (Reason 1990), and has since gained widespread acceptance and use in healthcare, in the aviation safety industry, and in emergency service organizations. It is sometimes called the cumulative act effect.
     The theory is that most accidents can be traced to one or more of four levels of failure: Organizational influences, unsafe supervision, preconditions for unsafe acts, and the unsafe acts themselves. In the Swiss Cheese model, an organization's defenses against failure are modeled as a series of barriers, represented as slices of Swiss cheese. The holes in the cheese slices represent individual weaknesses in individual parts of the system, and are continually varying in size and position in all slices. The system as a whole produces failures when all of the holes in each of the slices momentarily align, permitting (in Reason's words) "a trajectory of accident opportunity", so that a hazard passes through all of the holes in all of the defenses, leading to a failure.
     I won't bore you with more safety theories, but I understand that we all want to know the why and how of the Asiana crash.  Ultimately, the only thing that people will hear about is "pilot error," but I hope that this at least begins to make you aware of the fact that any accident involves more than the "mistakes" of just one or two people, especially if those two people are the pilots.