Accident Investigation

The following comes from a friend of mine, Dr. Antonio Cortés, the Associate Dean of the College of Aviation at Embry-Riddle Aeronautical University in Daytona Beach, Florida. He wrote these back in 2002 when he was a first officer for Midwest Express.

While the Dust Settles

An accident investigator helps make sense of the emotional frenzy following an airline accident.

With the Nov. 12, 2001, crash of American Airlines Flight 587 in New York fairly fresh in our minds, I would like to share some thoughts on the science of accident and incident investigation and on making sense of the chaos following a major airline accident. These musings have often helped me assuage the confusion of family, friends, flight attendants, and concerned passengers—all of whom grill me for answers following any type of aviation disaster.

The days following an airline accident contain a caustic blend of news media hype, "expert" analysis, and wild speculation. How can one come to terms with the deluge of theories and eyewitness accounts? How can we use our intellect to ease our emotional torment? First, we must start with the facts.

The 5-second rule

What facts? How can we start with facts when absolutely everything seems to be shrouded in speculation? At the end of the day of the accident, you can summarize the facts by answering, in 5 seconds or less, the question, "What happened?" In the case of American Flight 587, the summary would go something like this: "Today, an American Airlines Airbus 300 crashed shortly after takeoff from JFK Airport." That’s all!

Let’s face it, at this point, your 5-second statement contains almost all the indisputable facts that exist until an intensive investigation is complete, if then. This "5-second rule" works very well at winnowing out the facts from the chaff. Anything that cannot be summarized in 5 seconds usually belongs to the realm of speculation.

My recommendation is to check the news initially to come up with your own "5-second statement" and then ignore the news media for the most part over the next few days. You will miss the intriguing "expert" analysis (pointless), the footage of the NTSB team setting off for another investigation (useless), the wailing of the interviewed populace (disturbing), the often ridiculous eyewitness testimony (distracting), and other fascinating stories that leave you feeling emptier than when you started. Take comfort in the fact that you probably know about as much as anyone, including the NTSB, at this stage.

The news coverage following accidents, often labeled a "media circus," is heavy on emotion but lean on substance. If circumstances were different and human suffering were not an issue, some of the eyewitness testimony and reporters’ questions could be seen as downright hilarious.

I watched the news media’s coverage of the American Airlines Flight 587 crash with detached intellectual curiosity. Among my favorite questions asked of bystanders who claim they saw the jet crash was, "How high was the plane flying?" The range of answers was absolutely staggering. Then again, estimating the distance to the corner gas station with any accuracy is extremely difficult, even if you can see it. One person will tell you the gas station is a mile away, and the next will say 500 feet. How high was the plane flying? Well, I’m going to go out on a limb here and estimate, roughly, that the jet’s altitude at the time of impact was approximately zero feet. I mean, come on now!

Airline accidents are usually multi-causal, complex puzzles that demand time and attention to detail to solve.

I am reminded of the trick question asked of people as they take in the views from a scenic overlook on a sunny day: "What’s the farthest thing you can see?" Answers range from this or that geographic feature to this or that distant city, but no one ever mentions the obvious answer: the sun! At approximately 93 million miles, the sun is probably the farthest thing you can see from the overlook (at least until other stars become visible at night).

Questions that ask bystanders how they feel about an accident are especially indicative that a reporter has exhausted his or her repertoire of substantive questions and is resorting to emotional appeal to garner viewer interest. Yes, it’s pathetic, and it does absolutely nothing to quench your thirst to know the accident’s causes.

Another news media phenomenon, which I affectionately refer to as "journalistic inbreeding," occurs when reporters start interviewing reporters. The time has come to turn off the TV, before they start interviewing psychics.

Now mind you, the reporters have jobs to do, and they honestly try to do them as well as they can, but no one says that you have to watch, read, or listen to them. After all, we already know 90 percent of everything they are going to say!

"First facts" are anything but "facts"

How does this all tie in with the science of accident investigation? Consider two basic concepts: (1) almost all initial theories proposed during an accident investigation are flat-out wrong, and (2) accidents are multi-causal. That is to say, accidents are almost always due to a series of causes working synergistically against the victims in an "error chain."

Initial theories are, literally, "first guesses" as to what created the accident. During my training as an Air Force accident investigator, I convinced myself that I knew the causes of accidents I studied after only a few hours of introspection. Almost without fail, the first conclusions that my colleagues and I reached were flawed. Scenario after scenario, the only hard fact that emerged was that we needed to be completely objective when studying the initial clues.

Think back to the major accidents of 2001—the SAS MD-87 that crashed in Milan in the summer and the Tupolev 154 that mysteriously disappeared into the Black Sea, or 2000’s Alaska Airlines MD-83, which plunged into the Pacific Ocean off Pt. Mugu, and the Concorde accident near Paris. Do you remember the initial theories about the causes of these accidents? Some were extremely farfetched and proved to be totally wrong. Others were not farfetched enough, and the truth proved to be even more alarming than expected.

Once again, we cannot escape the notion that initial theories are often fraught with error, because they arise from conjecture in the absence of facts. Therefore, the best advice is to come to terms with the notion that you will not know the truth for quite some time, if ever. After all, experts still debate what brought down the Hindenburg more than 60 years ago.

The myth of "pilot error"

You’d be hard-put to find an accident or incident that is not multi-causal. Historically, accidents were often conveniently written off by deeming the cause to be "pilot error" and taking scant further action. The public was relieved to know that a single "bad apple" had created the problem, and the aviation world could return to business as usual.

In a sense, we treated the symptoms of a disease while permitting the underlying cause to grow unchecked.

Over the past few decades, investigators have shown that accidents usually have more than one cause and have thus produced tremendous advances in accident prevention. One byproduct of this investigative exposé has been the decreased use of the myth of pilot error.

I often think of pilots as soldiers who fight not for a piece of land, but for safety. Soldiers are only as effective as their equipment, training, support, and tactics. When a battle is lost, it is tempting to point at a defeated soldier and proclaim, "You failed!" Any general will warn you that such thoughts tend to boomerang right back in the face of those leaders who think that way. After all, the soldier’s failure represents poor resources and planning, which fall under the general’s purview. Thus, a soldier becomes a metaphor for a pilot, in that placing sole blame for an accident on a pilot is extremely shortsighted and ineffective.

Accident investigators dig up an error chain by "reverse engineering" the accident’s causes, so to speak. Whenever something of relevance is uncovered, an investigator must probe deeper by asking, "Yes, but why did that occur?" By asking, "Why? Why? Why?" over and over, an investigator can usually uproot most of the causal tree instead of just seeing the obvious branches. Only then can all the shortcomings of training programs, coordinating agencies, and quality-control measures be addressed to prevent future problems.

The teamwork involved in airline operations gets underscored as investigators uproot an error chain. Small mistakes, assumptions, or distractions in one area can add to those in another and so forth until, if no one intervenes to break the error chain, an accident or incident will occur. For example, the error chain for a windshear accident may look something like this: Unforecast weather + Inadequate windshear detection + No hint on ATIS + No ATC warning + Crew complacency = Accident.

An experienced investigator picks apart each of these causes and asks all the "whys" of each, until a comprehensive picture of the failures is seen and corrective actions can be recommended. Each error by itself will not bring down an aircraft, but the likelihood of an accident increases with each error "link" added to the chain.

So how does this all relate to us?

Modern society expects instantaneous answers that are simple yet comprehensive. I am reminded of the saying, "You want it bad? You’ll get it bad!" Airline accidents are usually multi-causal, complex puzzles that demand time and attention to detail to solve.

Let’s summarize the first few days following an airline accident: conflicting eyewitness reports, misdirected reporters’ questions, a tendency to believe initial causal theories because they sound good, and the temptation to oversimplify what happened. To wade through all that chaos, accident investigators must exercise patience and focus on minutiae, yet strive to see the big picture.

As awed spectators who have a stake in our profession, we can follow the lead of seasoned accident investigators by staying objective about an accident’s cause, recognizing that a confluence of several negative events is what brings down airplanes, being suspicious of early findings, and placing intellect over emotion by practicing patience. This is not just the smart and professional thing to do; it spares us a ton of emotional grief as well!