NYC01IA024

On October 26, 2000, at 1755 Eastern Daylight Time, a Bombardier CL-600 Regional Jet (CRJ), N958CA, experienced an in-flight upset while passing over the Falmouth VOR (FLM), Falmouth, Kentucky, at 10,850 feet. There was no damage to the airplane, and the 3-member crew and 47 passengers were uninjured. Visual meteorological conditions prevailed at the time of the accident. The flight was operating on an instrument flight rules flight plan, between Fort Lauderdale-Hollywood International Airport (FLL), Fort Lauderdale, Florida, and Cincinnati/Northern Kentucky International Airport (CVG), Covington, Kentucky. The scheduled passenger flight was conducted under 14 CFR Part 121.

According to the captain, the airplane was in level flight, with the autopilot engaged. The airplane rolled to the left, hesitated, then rapidly continued the left roll. The captain disconnected the autopilot, and manually returned the airplane to level flight. During the recovery, the captain noticed that the rudder trim was steady, and deflected approximately 1/2 scale. The captain also said that the first officer, "confirmed rudder deflection on ICAS flight cont. page."

The captain further stated that, "other than [the] significantly out-of-trim position of the controls, controls and trims responded well to manual input. Once recovered, aircraft flew well to touchdown."

According to data retrieved from the airplane's digital flight data recorder (DFDR), the airplane rolled 10 degrees to the left in 1/2 second, and to about 22 degrees left in another 1/2 second, before reaching a maximum of 24 degrees left in an additional 1/2 second. During the roll, the left aileron reached a maximum downward deflection of 6 degrees, while the right aileron reached a maximum upward deflection of 6 degrees, about 1/3 of a second later.

Prior to the roll, the rudder had been 1/2 degree to the right. During the roll, the rudder deflected a maximum of 6 degrees to the left within 1 second, then varied between 3 and 5 degrees left for the next 3 1/2 seconds. It remained about 2 degrees left for the following 35 seconds, before beginning to center.

Pitch attitude had been about 2 degrees up as the airplane entered the roll, then increased to 5 degrees up as the airplane came out of the roll, before stabilizing to between 1 and 3 degrees up. During the event, the airplane climbed about 250 feet, before descending back down to its original altitude.

Radar data indicated that the flight was at 10,850 feet when the event occurred. One minute, 24 seconds earlier, a Boeing 767-300 had flown through the same area, at 11,000 feet.

Winds, recorded on the CRJ's flight data recorder at the time of the incident, were from 318 degrees, at 10 knots. Weather conditions, at an airport about 30 nautical miles to the north, included surface winds from 220 at 6 knots, a few clouds at 5,000 feet, and a scattered layer at 25,000 feet.