What happened
During a takeoff roll intended for an elevator test, the aircraft experienced elevator binding, which forced the crew to abort the takeoff. The issue was identified as a mechanical interference within the elevator control mechanism.
The investigation
The investigation focused on the installation of the elevator drive torque tube. It was discovered that maintenance personnel had placed washers under the heads of the bolts used to attach the inboard portion of the elevator drive torque tube to the outboard portion of the tube.
Because these washers were not required by the installation specifications, their presence reduced the clearance between the bolt heads and the elevator structure. Under the flight loads generated during the takeoff roll test, this lack of clearance caused the binding. Investigators determined that the mechanics had simply copied a previous, incorrect installation they observed while removing the old elevator.
Following the incident, maintenance personnel consulted the Illustrated Parts Catalog (IPC), which confirmed that no washers should be used in this assembly. A subsequent inspection of the elevator installation on the opposite side of the aircraft showed it had been installed correctly without washers.