glencar
Ex Member
|
From the WSJ:
Pilot Action May Have Led to Crash Investigators examining last week's Continental Connection plane crash have gathered evidence that pilot commands -- not a buildup of ice on the wings and tail -- likely initiated the fatal dive of the twin-engine Bombardier Q400 into a neighborhood six miles short of the Buffalo, N.Y., airport, according to people familiar with the situation.
The commuter plane slowed to an unsafe speed as it approached the airport, causing an automatic stall warning, these people said. The pilot pulled back sharply on the plane's controls and added power instead of following the proper procedure of pushing forward to lower the plane's nose to regain speed, they said. He held the controls there, locking the airplane into a deadly stall, they added.
........
According to people familiar with the investigation, Capt. Marvin Renslow, 47 years old, who lived outside Tampa, Fla., was at the controls of Flight 3407. The safety board said Mr. Renslow was relatively new to the Q400, which he began flying only in December, when he upgraded from another type of airplane. First Officer Rebecca Lynne Shaw, 24, of Seattle, had accumulated 774 hours in the 74-seat aircraft.
The recovered flight data described in detail how the crew of Continental Flight 3407 handled the emergency, the people said.
During the flight from Newark, Mr. Renslow and Ms. Shaw noticed ice building up on the windshield and wings of the airplane after they had already activated the craft's de-icing system, which inflates a series of rubber bladders on the leading edge of the wings and tail surfaces to break up accumulated ice.
According to the plane's flight recorders, Flight 3407's descent into Buffalo was routine until roughly a minute before impact, when the crew lowered the landing gear, followed by the command to extend the wing flaps, which enable the plane to fly at slower speeds.
Almost immediately, these people say, the plane's air speed slowed rapidly, causing a stall-warning device known as a "stick-shaker" to cause the pilots' control column to vibrate. This was followed by a "stick-pusher," which automatically forces the stick forward.
At this point, the captain appears to have pulled back with enough force to overpower the stick-pusher and shoved the throttles to full power, according to people familiar with the matter. Safety board officials said the nose pitched up to a 31-degree angle. Already at a dangerously low speed, the wings immediately stopped generating lift. The plane whipped to the left and then entered a steep right turn, losing 800 feet of altitude in less than five seconds. At one point the right wing was perpendicular to the ground, according to information taken from the flight data recorder.
The pilots continued to fight with the controls almost all the way to the ground, and in the final moments, "it appeared that they were beginning to make headway when they ran out of altitude," said one person who looked at the data.
|