When an Asiana Airlines Boeing 777 airplane crashed at the San Francisco International Airport, it was traveling far below the 137 knots per hour (157 miles per hour) required for a safe landing.
Now, the Los Angeles Times reports that the pilots told investigators that an automatic throttle did not function properly during landing. Auto throttles give pilots the option to set the plane's speed at any part of the flight, including landing. The pilots claim they set the speed to 137 knots and did not notice that the auto throttle was not maintaining speed until it was too late to correct the speed and abort the landing.
Which raises more questions: Did an auto-pilot defect cause the Asiana airplane crash? Were the throttles activated correctly? Are the pilots responsible for failing to monitor the aircraft's speed?
Yet, as one air safety consultant, Barry Schiff, told the LA Times, "Whether [the auto throttle] was engaged or not working is almost irrelevant. The big mystery of Flight 214 is why ... did these two pilots sit there and allow the air speed to get so low." Why were they not properly monitoring the air speed before the plane crash?
It appears that the pilots (one of whom was in training and had never landed at San Francisco International Airport) did not notice how slow the plane was traveling until a stall warning advised them of the problem. The pilots then unsuccessfully attempted to abort the landing and accelerate to prevent the accident.
Many safety experts have noted that the pilots had ultimate responsibility to maintain the aircraft safely, including monitoring the auto pilot systems. Yet, the airplane's manufacturer and the manufacturer of the auto throttles may also hold some responsibility for this serious plane crash that killed two people and injured 182, many critically.
Source: Los Angeles Times, "Asiana Airlines Pilots Say Auto-Throttle Didn't Maintain Landing Speed," Dan Weikel, Ralph Varabedian, Laura J. Nelson