ABC News has learned that the pilot of the Continental Express commuter plane that crashed in Buffalo, N.Y. Feb. 12 may have put the plane into its deadly plunge.
A source close to the investigation says information from the flight data recorder indicated that the pilot's control column, essentially the device he uses to steer the plane, moved sharply backward, pitching the nose of the turboprop upward.
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Investigators say they were surprised that a pilot would take that action so they want to make sure there isn't some other explanation for the movement of the plane's controls.
"There is no reason that I can think of that a pilot would voluntarily pull the nose up to 30 degrees after a stall warning," ABC News aviation consultant John Nance said today. "This has got to be some combination of misperception, misunderstanding of what was happening, or something else that we haven't discovered yet."
Nance said it's premature to say the crash was the result of a pilot's error.
"It's really wrong to assign an individual error to the pilot or to the crew because they may have been reacting to something that they perceived, and that reaction may have been exactly right and the perception was wrong," said Nance.
"We don't know exactly what this pilot was seeing, feeling, and perceiving at that point and until we've got a pretty good idea of that we're not going to know why that yoke moved back," Nance added.
Today, Colgan Air, which operated the flight for Continental, defended the pilot's experience and stressed confidence in its operations.
"Colgan has instilled a systemic culture of safety throughout our organization that is rooted in significant investment in crew training, systems, leadership and equipment," the airline said in a Wednesday statement. "Our crew training programs meet or exceed the regulatory requirements for all major airlines. Our ground and air training is designed in coordination with the aircraft manufacturer, one of the most respected providers of aviation flight training and the Federal Aviation Administration utilizing state-of-the-art training devices, such as full-motion simulators, among others."
The violent pitch up occurred just after the pilots received a warning in the cockpit that the plane was about to stall. A stall occurs when the airflow has been disrupted over the wings or tail and the plane can no longer stay aloft. Icing may still have been a factor, contaminating the wing or tail and making a stall more likely. In aviation lingo, a stall doesn't mean the engines stopped running -- the National Transportation Safety Board has said the plane's engines were at full power. Instead, the stall in this case refers to a lack of lift on the wing or tail, causing the aircraft to fall.
The normal stall recovery procedure for wing icing is to push the nose down and add engine power. A tail stall recovery calls for the opposite action, pulling the nose up and reducing power. In this case, the pilot appeared to have pulled up, but also increased engine power to its maximum setting.
"If you think you're stalling, you don't pull, you push," Nance explained.
After the sharp pitch-up, the plane's nose went down 45 degrees. It rolled to the left, then far to the right, partially upside down.