Airworthiness Directives; Fokker Model F27 Mark 050 Airplanes

The FAA is superseding an existing airworthiness directive (AD), which applies to all Fokker Model F27 Mark 050 series airplanes. The existing AD currently requires using a torque wrench to repetitively tighten the screws for the attachment of the leading edges of the elevators, rudder, and ailerons. This new AD requires the same actions as those of the existing AD, but with reductions in the intervals for repetitive actions. This AD also requires modifying the elevator, rudder, and aileron leading edge attachments with additional locking devices. This AD results from a report of an in-flight vibration caused by a loose leading edge section of the elevator. We are issuing this AD to prevent binding of the flight controls caused by loose attachment screws, which could result in reduced controllability of the airplane.