“The flight data recorder from a USAir Boeing 737 which crashed near Pittsburgh three years ago showed the control column pulled fully back as the bank angle reached 90 degrees and staying there as the aircraft rolled fully upside down.
"In 1991 there was a similar crash of a United 737 at Colorado Springs. The FAA investigators considered the possibility that the aircraft was upset by turbulence and that the pilots’ reactions were not timely and appropriate. Keeping the control column fully aft while inverted is not a good survival tactic for an aircraft of this size, which highlights the need for even the most basic aerobatic skills when flying for a commercial operator.

"Training should include flights in aerobatic aircraft to practice recovery techniques because no simulator can model the disorientation of actually being upside down... recurrent training every two years, with time in an actual aircraft, would be a good start.”

Source: Aviation Week & Space Technology, May 8, 1995
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