Do Computers Make Planes Less or More Safe?

In other words, the pilot in the Airbus flight deck is constantly digitally monitored and provided for. This new safety philosophy seemed irresistible at first. Nevertheless, its introduction was accompanied by a disaster. Three months after the initial delivery of the A320, an Airbus crashed, in front of live cameras, into a forest during an air show in Alsace in 1988. The image of a huge cloud of smoke rising above the treetops seemed like a bad omen, and some believed Airbus would never recover from this setback.

Was it merely a mishap, practically unavoidable whenever a new technology is introduced? Or did it expose a fundamental weakness in the new Airbus philosophy?

The experts argued passionately over the question. Some said that the computers and the pilot were not communicating properly in what was a complicated flight maneuver. Airbus still maintains that the pilot's behavior was not sufficiently disciplined.

Another accident occurred five years later, on a stormy day in Warsaw. In heavy wind and rain, a Lufthansa A320 slid off the end of the runway and broke apart. Two people died. The wind had suddenly turned, and perhaps the pilots should have aborted the landing. Instead, they carefully brought down the plane. Because of hydroplaning, the tires did not rotate on the wet runway. This confused the flight computer, which failed to recognize that the jet had already touched down. The system hesitated for nine seconds before the flight computer finally allowed the thrust reversers and brake flaps to engage -- nine long seconds in which the pilots were forced to look on helplessly as the jet rapidly approached the beaconing at the end of the runway.

At the time, Boeing more or less openly touted its own strategy, which gave the pilots more options to intervene. It cited the case of a Boeing 747 that two Chinese pilots had saved from an almost hopeless situation, in which the craft was exposed to four times the force of gravity. The Airbus computers wouldn't have allowed the pilots to perform such a radical maneuver.

Airbus fired back with its own examples. One was of a Boeing 757 that had crashed in Columbia, killing 159. The collision warning system had warned the crew of an impending collision. The pilot pulled up the plane, but it failed to clear the mountain ridge it was approaching, because he had forgotten to retract the brake flaps. An A320, Airbus said, would have done this automatically.

The PR battle has since been decided, according to the aircraft maker based in Toulouse, France, where a senior safety official says: "The accident statistics prove that we were right."

His claim is difficult to refute, because a meaningful comparison of accident figures between Boeing and Airbus models doesn't exist. However, the statistics also do not suggest that there is a clear advantage to the Airbus strategy. Aircraft made by both manufacturers crash, and whenever it comes time to investigate the causes of an accident, Airbus takes pains not to allow any questions to be raised about its fly-by-wire system. The company has played down the Qantas incident, saying that speculation is pointless before the ATSB releases its final report. This is even more applicable, says Airbus, to the case of the Air France A330 crash.

Boeing or Airbus? Among pilots, this has become almost a question of faith. "That's just as hard to decide as the question of whether Mercedes or BMW is better," says pilot representative Braun.

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