Trim Issue Sent Challenger 300 Into 4.2 G Upset, Killing Passenger

A fatal mishap that was originally reported as turbulence-related turned out to be a suspected issue with the stabilizer trim on the Challenger 300, according to the NTSB preliminary report….

A fatal mishap that was originally reported as turbulence-related turned out to be a suspected issue with the stabilizer trim on the Challenger 300, according to the NTSB preliminary report. The privately operated flight left Keene, New Hampshire, on a flight to Leesburg, Virginia, in the late afternoon of March 3. A passenger aboard the aircraft was killed during an in-flight upset, and at the time the FAA confirmed other reports that turbulence was involved but that was an error. It seems the correct checklist response to an Engine Indicating and Crew Alerting System (EICAS) stabilizer trim alert (moving the stabilizer trim switch from Primary to Off) sent the plane into a couple abrupt climbs and descents that recorded a maximum of 4.2 Gs.

"As soon as the switch position was moved, the airplane abruptly pitched up," the report says. "The PIC reported that his left hand was on the flight controls and his right hand was guarding the right side of the flight controls. He immediately with both hands regained control of the airplane in what he estimated to be a few seconds after the airplane’s pitch oscillated up and down." The crew diverted to Bradley International Airport at Windsor Locks, Connecticut, and the passenger, a former White House lawyer from Virginia, was rushed to a local hospital, where she died. As for the turbulence that was initially reported as the cause of the upset, it didn't exist. "The flight crew reported that they did not experience any remarkable turbulence during the flight, nor during the time immediately surrounding the in-flight upset event," the report says.

The flight did not start out well, either. During the takeoff run, the first officer noticed an airspeed disagreement between the two MFDs and the takeoff was aborted at 104 knots. After they stopped, the FO jumped out of the aircraft and discovered one of the two pitot covers still in place. He removed it, saw no damage and the crew took off again.

Russ Niles is Editor-in-Chief of AVweb. He has been a pilot for 30 years and joined AVweb 22 years ago. He and his wife Marni live in southern British Columbia where they also operate a small winery.