Airworthiness Directives; British Aerospace BAe Model ATP Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace BAe Model ATP airplanes, that requires a detailed visual inspection of the flap drive torque tubes in the wing root area to detect inadequate clearance between the torque tubes and surrounding structure or scoring damage to the tubes; and follow-on repetitive inspections or corrective action, if necessary. Accomplishment of certain replacements and modifications would constitute terminating action for the repetitive inspections. This amendment is prompted by reports of inadequate clearance between flap drive torque tubes and surrounding structures, and possible scoring damage to the tubes. The actions specified by this AD are intended to prevent failure of the torque tubes, which could result in an asymmetric flap condition and reduced controllability of the airplane.