Elevator Malfunctions In MD-83’s Rejected Takeoff
Jon Sanderson
WASHINGTON—Ameristar Jet Charter pilots attempting to takeoff from Runway 23L at the Willow Run Airport in Ypsilanti, Michigan, on March 8, were not able to lift the nose of the aircraft at the 152-kt. takeoff speed due to a jammed right elevator.
According to a preliminary report by the NTSB, flight data recorder (FDR) information showed that the pilots continued accelerating for 5 sec. with no pitch change, until reaching a speed of 166 kt., before initiating a rejected takeoff procedure.
The MD-83, operated by Ameristar Air Cargo, reached a maximum speed of 173 kt. (199 mph) before decelerating.
The aircraft—carrying the University of Michigan men’s basketball team to Washington for a Big Ten tournament game—traveled 1,000 ft. past the end of the runway, coming to rest in a field where the 109 passengers and seven crewmembers evacuated, using escape slides. One passenger received a minor injury. The NTSB said the forward right slide did not deploy correctly.
Ameristar’s chief pilot, in the right seat, was acting as pilot-in-command and providing “differences training” to the pilot-flying in the left seat. Both pilots had the correct type ratings and thousands of hours in DC-9-type aircraft. A strong headwind with right crosswind component was blowing at the time of takeoff, from 260 deg. at 35 kt., gusting to 50 kt.
According to investigators, a post-accident examination revealed that the cockpit controls moved normally; however, upon inspecting the elevator assembly on the tail, investigators found the right side to be jammed. The cause was a bent linkage to a control tab on the trailing edge of the right elevator, which prevented the elevator from moving from to the nose-up position. The left side of the split elevator functioned normally.
The FDR showed that the left elevator moved normally throughout the incident, but the right elevator did not. Data from previous flights showed both elevators operating normally.
One possible cause the NTSB will investigate is whether strong winds may have damaged the elevator while the aircraft was parked after arriving March 6 in Ypsilanti. According to Weather Underground, winds were gusting to 25 kt. March 6, to 35 kt. March 7, and to 50 kt. March 8.
The NTSB, which did not make any conclusions in the preliminary report, plans to issue a final report in 12–18 months.
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