A terrifying situation develops minutes after an AirPeru Boeing 757 leaves Lima for Chile. The central computer that governs the instruments appears to blow a fuse. The pilots are deprived of information about air speed and altitude. Not only that but one warning after another sounds. The instruments are erratic and the warnings are offering contradictory actions.
It's night, and the crew are unable to orient themselves over the dark Pacific Ocean. The air traffic controller is guiding them back to the airport at Lima but, though he doesn't know it, he's receiving the wrong information about altitude. The situation becomes critical in the cockpit. The "Overspeed" warning comes on, indicating that the airplane is flying too fast. Simultaneously, the controls begin to shake, an indication that they are flying too slow and about to stall. And it's all happening too quickly to be thought through bit by bit.
The pilots request interception by another airplane to provide guidance, since they can't tell where they are or how fast they're flying. In the US, the Coast Guard provides such interception and they're extremely efficient. I've seen them go from a cold start to take off in about five minutes. But that wouldn't have solved AirPeru's problems.
Everyone aboard is killed in the crash. With the help of the US Navy robotic recovery machine and the National Transportation Safety Board in Washington, the two "black boxes" -- the cockpit voice recorder and the flight data recorder -- are analyzed.
So why did the computer go berserk? It was remarkably simple. The instruments on both the pilot's and the co-pilot's side get information from hollow tubes, Pitot tubes, on each side of the aircraft. The ports were blocked with tape. It's routine to cover the static ports while cleaning the airplane but the maintenance worker forgot to remove the tape, and his supervisor was out sick, replaced by a mechanic who also failed to notice the tape. The captain did a "walk around" before take off, looking for exactly that kind of anomaly, but he didn't notice it either.
There followed law suits galore. AirPeru and Boeing settled out of court and the families of the victims were awarded about one million dollars per victim. The mechanic who forgot to remove the tape wound up in jail.
It's night, and the crew are unable to orient themselves over the dark Pacific Ocean. The air traffic controller is guiding them back to the airport at Lima but, though he doesn't know it, he's receiving the wrong information about altitude. The situation becomes critical in the cockpit. The "Overspeed" warning comes on, indicating that the airplane is flying too fast. Simultaneously, the controls begin to shake, an indication that they are flying too slow and about to stall. And it's all happening too quickly to be thought through bit by bit.
The pilots request interception by another airplane to provide guidance, since they can't tell where they are or how fast they're flying. In the US, the Coast Guard provides such interception and they're extremely efficient. I've seen them go from a cold start to take off in about five minutes. But that wouldn't have solved AirPeru's problems.
Everyone aboard is killed in the crash. With the help of the US Navy robotic recovery machine and the National Transportation Safety Board in Washington, the two "black boxes" -- the cockpit voice recorder and the flight data recorder -- are analyzed.
So why did the computer go berserk? It was remarkably simple. The instruments on both the pilot's and the co-pilot's side get information from hollow tubes, Pitot tubes, on each side of the aircraft. The ports were blocked with tape. It's routine to cover the static ports while cleaning the airplane but the maintenance worker forgot to remove the tape, and his supervisor was out sick, replaced by a mechanic who also failed to notice the tape. The captain did a "walk around" before take off, looking for exactly that kind of anomaly, but he didn't notice it either.
There followed law suits galore. AirPeru and Boeing settled out of court and the families of the victims were awarded about one million dollars per victim. The mechanic who forgot to remove the tape wound up in jail.
