The Fear: Was Air France 447 a Computerized Crash?
There is little known about what actually happened to Air France Flight 447, a non-stop from Rio de Janeiro to Paris, that never made it.
But already the camps are forming, and this is shaping up to be one of the formative philosophical battles of the modern era, pitting those who have faith in the technology that works the systems we use every day in every walk of our lives, and those who do not have such faith. And this is not just an aviation issue.
There is a long-simmering debate over the question of whether Airbus aircraft utilize too much technology to keep their airplanes safe from harm, thereby preventing the pilots from taking corrective action in the case of a malfunction. The first crash of an Airbus, at an airshow in 1988, has, in the view of many, never been satisfactorily explained. The A320-111 was executing a low pass and never gained altitude, as it settled into trees at the end of the runway. Three of the 130 onboard died in the crash, and the data from the flight recorders was compromised, so questions will remain. But many, including French pilots' unions, believed the safety systems, prevented the pilots from adding power and recovering the airplane. French investigators eventually ruled the crash was solely due to pilot error.
And whether we ever know just what happened to Flight 447 will depend on whether searchers recover the airplane's recorders, and today, with listening and recovery vessels on site or on their way, there is hope that they will be found.
Already we know, from automated messages sent by the airplane, that there were inconsistencies between the airspeed readings on the different displays, and we know that Air France is busy replacing those sensors fleet wide at this time. But what we don't yet know is why those sensors failed, if indeed they did. Was it because of icing? And what was the response of the autoflight system to those faulty inputs? We do know that the autopilot shut down, but by then was it already too late? Had the faulty speed readings already prompted the autopilot to fly the airplane into a regime of flight that human pilots couldn't fly back out of? The argument will be--and you will hear this, if you haven't already--that the envelope protection on the A330 prevented the human pilots from saving the flight, that technology in this case was lurking around the corner, like a trained wolf, seeming to be our friend but secretly waiting for an opportunity to leap at our throats.
Before we leap to any such conclusion, though, I think it's important that we look at the conditions that the Airbus encountered. Anyone who's ever wandered too close to a thunder storm--and several years ago I was a passenger on a US domestic flight that did just that-- knows that there are forces contained in a strong storm that stagger the imagination and can defeat any airplane and any crew.
If the storm that 447 encountered was as fierce as it seemed, for all we know the autoflight system merely delayed the inevitable. And if the autopilot were fooled by faulty readings, and that is certainly a possibility, the question needs to be asked: Just how well would the human crew have fared in handling the challenge of flying an airplane in the dark in the middle of a raging storm with bad primary flight data? We do know that they were unable to recover once the autopilot disconnected. Was it too late by then? Maybe.
But we should keep the facts straight here. Airbus jets are built to hand control of the airplane back to the pilot, depending on the "laws" of the situation. The computer normally determines what current law applies, but pIlots can manually take direct control of the airplane, disabling all of its envelope protection. So any argument that the airplane prevented the pilots from doing their job is hard to believe.
Moreover, there has been a great deal of discusson about the fly-by-wire system. Could a strong strike have disabled it? Highly unlikely. The reliability and redundancy of fly-by-wire controls is phenomenally good.
So did electronics doom Flight 447? it is very unlikely.
If we do recover the recorders and successfully extract their data, we will know much more. But even before then, it's clear that the crash of Air France 447 occurred at the intersection between technological and human input.
And I have no doubt that we will be discussing this accident, and its probable or possible causes, for many years to come, and I have little doubt that those discussions will inform our future decisions about what we ask machines to do for us and what we don't. How solidly those decisions are based on fact and not fear remains to be seen.