The actuators that move the elevators of a privately operated MD-87 that crashed at Houston Executive Airport Oct. 19 were jammed in the trailing edge down position and that made it impossible for the aircraft to take off. The NTSB preliminary report says the elevator actuators were both bent enough that they prevented the elevators from fully responding to pilot control inputs. “Upon reaching rotation speed, the recorded elevator positions split, but neither moved to a trailing edge up position,” the report says. The aircraft ended up 1400 feet off the end of the runway after the rejected takeoff. All 23 occupants escaped and two were seriously injured. Most of the plane was consumed by a post-crash fire but the tail stayed intact.
The elevators on those types of aircraft are not directly connected to the control yoke. Rather, they are free hinged and moved up and down aerodynamically through the manipulation of small control tabs on the trailing edge. Therefore, there is no way to check the operation of the elevators during the preflight. The report doesn’t say how the actuators that connect the tabs to the elevators got bent but it does draw comparisons to the overrun of an MD-83 in Michigan in 2017. In that incident, the board concluded that the actuators were damaged by high winds while the aircraft was parked. The aircraft in the Houston mishap had reportedly been parked for 11 months and there has been plenty of wind in the Houston area in that time. All the components and recorders are being studied by investigators and the official cause of the crash won’t likely be released for a year or more.
