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clydes's activity in the archive.
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The authors point is irrelevant. It is not some design "policy" decision difference between Americans and Europeans pertaining to attitudes toward personal freedom. It is about the design decisions made, the quality of the designers and manufacturers, the quality of aircraft maintenance, pilot traing, etc. And in some cases just bad luck. If the accident turns out to be pitot tube icing, then the mode of accident would have been the same for Boeing and Airbus (read example below) Yes, this is a well known difference between Airbus and Boeing. I for one, prefer Boeings approach. But Boeings approach is, and always has been, to build a more robust aircraft anyway. Airbus builds essentially throw-away aircraft, after 20-30 years they're done. Whereas, you can still find few 707s flying , the last produced in 1979. And look at B-52s, the last was produced in 1962, but all have been re-skinned by now. But Airbus and Boeing are full of computers for many tasks. To the point here, yes computers take control any from the pilots to an extent - but the failure rate of the fly-by-wire systems are comparable to those of the more traditional hydraulic systems in terms of accidents and casualties. The leading theory seems to be that the pitot system iced over - essentially failing producing incorrect airspeed measurements - probably caused by icing in bad weather. This did cuase several things to occur, the least of which being confusion on the part of the pilots. The readings probably showed the pilots and the computer low airspeed, indicating to both the danger of a stall. So the pilot would want to increase power, and the computer generally speaking would probably try to get out of autopilot to allow the pilot control. The problem here is that when flying at high altitude control the aircraft is in what aeronautical engineers call a coffin corner in the performance envelope - because of the very low density at altitude the stall speed of the aircraft is much higher than near the ground, and because of the speed the aircraft is also working toward the structural limits of the aircraft. A good example of potentially a similar accident is Austral LÃneas Aéreas Flight 2553, a DC-9 (hydraulic vs. computer). The aircraft diverted to avoid a storm, but shortly thereafter started showing dangerously low airspeed. Pilots reacted by increasing power, but saw no increase in airspeed. At this point the pilots deplyed slats; one of which promptly tore off making the wings assymetric. the aircraft was uncontrolable and crashed vertically into the ground. The culprit was an iced over pitot tube which caused false speed readings. The pilots deployed slats well above safe deployment speed. The B-1 that crashed on takeoff on Gaum was traced back to the pitot tube system if I remember correctly. The system indicated a higher than actually airspeed so the flight computer rotated the nose up at too low an airspeed causing the aircraft to stalll and crash. Pitot tube faults (due to maintenance, not icing) have been attributed to two Boeing 757 crashes - Birgenair Flight 301 (189 fatalities) and Aeroperà Flight 603 (70 fatalities). The difference in Airbus and Boeing is that for the former the limit (flight envelope protection) is determined by the computer, and in the later by the hydraulics. In the Airbus system the computer determines the limits of control; the pilot can increase the limit by selecting and alternate mode. In the Boeing case, the pilot can excede flight envelopes by exerting more force on the flight controls - allowing the pilotto do what the computers do not calculate as correct. American Flight 587 (Airbus 300) in New York in 2001 is an example of a crash that could have been averted if flight envelope control had been in place. The aircraft was flying at an altitude and airspeed at which the pilot could defelct the rudder enough that the aerodynamic forces exceded the structural limits of the aircraft, eventually causing the tail to break off. We should not be quick to condemn the computers as the p
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last link: http://www.airdisaster.com/statistics/
The authors point is irrelevant. It is not some design "policy" decision difference between Americans and Europeans pertaining to attitudes toward personal freedom. It is about the design decisions made, the quality of the designers and manufacturers, the quality of aircraft maintenance, pilot traing, etc. And in some cases just bad luck. If the accident turns out to be pitot tube icing, then the mode of accident would have been the same for Boeing and Airbus (read example below) Yes, this is a well known difference between Airbus and Boeing. I for one, prefer Boeings approach. But Boeings approach is, and always has been, to build a more robust aircraft anyway. Airbus builds essentially throw-away aircraft, after 20-30 years they're done. Whereas, you can still find few 707s flying , the last produced in 1979. And look at B-52s, the last was produced in 1962, but all have been re-skinned by now. But Airbus and Boeing are full of computers for many tasks. To the point here, yes computers take control any from the pilots to an extent - but the failure rate of the fly-by-wire systems are comparable to those of the more traditional hydraulic systems in terms of accidents and casualties. The leading theory seems to be that the pitot system iced over - essentially failing producing incorrect airspeed measurements - probably caused by icing in bad weather. This did cuase several things to occur, the least of which being confusion on the part of the pilots. The readings probably showed the pilots and the computer low airspeed, indicating to both the danger of a stall. So the pilot would want to increase power, and the computer generally speaking would probably try to get out of autopilot to allow the pilot control. The problem here is that when flying at high altitude control the aircraft is in what aeronautical engineers call a coffin corner in the performance envelope - because of the very low density at altitude the stall speed of the aircraft is much higher than near the ground, and because of the speed the aircraft is also working toward the structural limits of the aircraft. A good example of potentially a similar accident is Austral LÃneas Aéreas Flight 2553, a DC-9 (hydraulic vs. computer). The aircraft diverted to avoid a storm, but shortly thereafter started showing dangerously low airspeed. Pilots reacted by increasing power, but saw no increase in airspeed. At this point the pilots deplyed slats; one of which promptly tore off making the wings assymetric. the aircraft was uncontrolable and crashed vertically into the ground. The culprit was an iced over pitot tube which caused false speed readings. The pilots deployed slats well above safe deployment speed. The B-1 that crashed on takeoff on Gaum was traced back to the pitot tube system if I remember correctly. The system indicated a higher than actually airspeed so the flight computer rotated the nose up at too low an airspeed causing the aircraft to stalll and crash. Pitot tube faults (due to maintenance, not icing) have been attributed to two Boeing 757 crashes - Birgenair Flight 301 (189 fatalities) and Aeroperà Flight 603 (70 fatalities). The difference in Airbus and Boeing is that for the former the limit (flight envelope protection) is determined by the computer, and in the later by the hydraulics. In the Airbus system the computer determines the limits of control; the pilot can increase the limit by selecting and alternate mode. In the Boeing case, the pilot can excede flight envelopes by exerting more force on the flight controls - allowing the pilotto do what the computers do not calculate as correct. American Flight 587 (Airbus 300) in New York in 2001 is an example of a crash that could have been averted if flight envelope control had been in place. The aircraft was flying at an altitude and airspeed at which the pilot could defelct the rudder enough that the aerodynamic forces exceded the structural limits of the aircraft, eventually causing the tail to break off. We should not be quick to condemn the computers as the p