Air crashes and the rush to judge

When a plane crashes, who doesn't want quick - comforting - answers to dozens of questions?

But as airline safety advances, quick answers about accidents are going to be a lot harder to come by. Most simple causes for crashes have been eliminated through what we've learned from past accidents. More complex causes - the stuff of lingering mystery and public concern - are the future of airline crashes.

The international furor over the rush to judgment on the crash of EgyptAir 990 last month is just a sample of what's to come if we don't somehow control our seemingly irresistible urge to speculate, and if we don't show some patience while accident investigators do their work.

One would hope we'd have learned our lesson from the frenzy of speculation surrounding TWA 800. Apparently we didn't.

The problem isn't that we want answers, but that in our eagerness we jump to conclusions with only fragmentary or no evidence. The resulting speculation contributes nothing to help the National Transportation Safety Board (NTSB) and others determine the real causes of the accident, does nothing to improve safety, and doesn't make the tragedy any easier to bear for those who've lost loved ones. Safety isn't improved when journalists compete to be first to report the cause. Safety is improved by careful actions taken once the causes of an accident are well understood.

The speculation often seems like a catalog of the suspected, often unproven, causes of recent crashes. Within hours of the EgyptAir crash, some speculated about wire insulation (suspected in the 1998 Swissair crash). Others raised the specter of a problem with the thrust reverser (the cause of the 1991 Lauda Air crash).

EgyptAir was then condemned by some as having one of the world's worst airline safety records - an inaccurate condemnation.

As bits of evidence emerged, from the aircraft radar track and from the flight data recorder, that there probably wasn't a fire in the wiring or a failure of a thrust reverser, attention turned to the cockpit. Some speculated a terrorist might have entered and caused the crash (the cause of the 1987 Pacific Southwest Airlines crash) or that one of the pilots might have committed suicide by intentionally crashing the plane (suspected in the 1997 Silk Air crash).

Then, as the first small pieces of evidence began to emerge from the cockpit voice recorder, speculation - in bold headlines - turned to the actions of one of the crew, based on a phrase uttered apparently shortly prior to disengaging the autopilot. Now the head of the NTSB is sniping at sources that leaked the information, calling it "flat-out wrong."

Without clear and conclusive evidence, speculating about - or even implying - the causes is simply irresponsible. Modern airline accidents are usually complex events that don't reveal their causes quickly or easily.

As aircraft and their various components have been developed and improved over the years, many of the straightforward causes of airline accidents prevalent in the past have been largely eliminated. Engines and control systems are much less prone to failure; wings don't fail from metal fatigue; pilots have better information to help avoid wind-shear conditions; weather forecasting and navigational aids have improved; pilots receive much more comprehensive training; and ground proximity warning systems largely prevent pilots from inadvertently flying into the ground.

As a result, accidents are less frequent when measured against the global growth in airline travel. The accidents that do occur are likely to have more subtle, complex causes.

The elimination of many of the past causes of airline accidents has consequences. It is increasingly difficult for NTSB and others to point definitively to the unambiguous cause of every accident.

Investigations will take longer, the more uncertainty there is. This uncertainty about accident causes can lead to uncertainty about the effectiveness of steps taken to improve safety in response to an accident. So it may become increasingly difficult to continue to get the dramatic improvements in aviation safety that we've come to expect from the progress of the last 50 years.

There are still safety improvements to be made, but we shouldn't be surprised if progress is a bit more modest in the future.

*Clint Oster is a professor in the school of public and environmental affairs at Indiana University, in Bloomington. He is co-author of 'Why Airplanes Crash' (Oxford University Press, 1992).

(c) Copyright 1999. The Christian Science Publishing Society