Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Fokker Model F28 Mark 0100 series airplanes. This proposal would require repetitive checks to detect backlash in the elevator mechanical control system, and various follow-on actions. The proposed AD would also provide for an optional terminating action for the repetitive check requirements. This proposal is prompted by a report indicating that corrosion was found on the pivot bolts and bushings of the backlash remover lever mechanism on the elevator booster control unit (BCU) of a Model F28 Mark 0100 series airplane. The actions specified by the proposed AD are intended to prevent such corrosion, which could result in backlash in the elevator controls and reduced elevator control authority in the manual mode.