Summary
This document proposes to adopt a new airworthiness directive that would apply to Pilatus Britten-Norman Ltd. (Pilatus Britten- Norman) BN-2A, BN-2B, and BN-2T series airplanes. The proposed AD would require repetitively inspecting the junction of the torque link lug and upper case of the main landing gear (MLG) torque link assemblies for cracks, and replacing any MLG torque link assembly with a Modification A39 MLG torque link assembly, either immediately when cracks are found or after a certain period of time if cracks are not found. Replacing all MLG torque link assemblies with Modification A39 MLG torque link assemblies would eliminate the need for the repetitive inspections. These proposed repetitive inspections are currently required by AD 86- 07-02 for the BN-2A, BN-2B, and BN-2T series airplanes, as well as the BN2A MK. 111 series airplanes. There are no improved design parts for the BN2A MK. 111 series airplanes. The Federal Aviation Administration (FAA) is issuing in a separate action a proposed revision to AD 86-07- 02 to retain the repetitive inspection and replacement (if cracked) requirements for the BN2A MK. 111 series airplanes. The actions specified in the proposed AD are intended to prevent failure of the main landing gear caused by cracks in the torque link area, which could lead to loss of control of the airplane during landing operations.