Federal investigators Tuesday revealed key moments in the final minutes of Asiana Airlines Flight 214 that caused the Boeing 777 to fly into San Francisco International Airport too low and slow, and ultimately crash.
During a hearing in Washington, D.C., investigators with the National Transportation Safety Board determined that last summer's crash was caused by pilot "mismanagement," saying they were confused over aspects of the jet's key controls. The board also cited issues with the complexity of those controls and the training the pilots received.
The NTSB released a four-minute animated video that detailed how the jet fell "well below" the desired glide path and reached a "rapidly dropping" speed not safe for the landing. An alarm sounded 11 seconds before the plane clipped a sea wall and slammed into the runway.
Three people — all high school students from China — were killed and more than 180 were injured in the July 6 crash.
The NTSB animation describes the following sequence of events:
The animation begins with the plane's autopilot on, directed for a 14-mile final approach. At that point, the narrator said, “through a sequence of speed and configuration changes, the flight had diverged well above the desired glide path and was descending too slowly."
Though the landing gear was extended, the pilot monitoring the flight noted: "This seems a little high."
"I will descend more," the pilot flying the plane said.
The autopilot was then programmed to descend the plane at 1,500 feet per minute. The move initially put the plane back toward the desired glide path, but about six miles out from the runway, the descent rate was set back to 1,000 feet per minute.
The plane was still "still well above" the desired glide path. About five miles out from the runway, it was still about 400 feet higher than desired.
Crews then began slowing the plane. The pilot flying the jet switched the auto pilot to the "flight level change mode," but that didn't help with the descent. Instead, the plane began to climb to an altitude of 3,000 feet an autopilot command set earlier in case the pilots decided to abort the landing.
To keep the plane from climbing, the pilot disconnected the autopilot and put the thrust levels on idle. That put the auto throttle in hold mode, when the auto throttle doesn't control air speed.
The plane began descending at a rate of about 1,500 feet per minute. Just under 1 1/2-miles from the runway, it fell through the desired glide path and below the approach speed. The pilot tried to maintain the glide path, but the jet continued to fall, traveling 15 knots below the desired speed "and rapidly dropping."
An alarm then sounded, warning that the speed was too low. Four seconds later, the pilot monitoring the flight tried to advance the throttle and called for a "go-around" — an aborted landing.
"These actions were too late," the narrator said.
The video ends with surveillance footage of the jet slamming into the runway, its tail breaking off as it careened down the runway. It ultimately spun on its nose before coming to rest in a plume of smoke.
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