Summary
This document proposes to adopt a new airworthiness directive (AD) that would apply to all British Aerospace (Operations) Limited (British Aerospace) Model B.121 Series 1, 2, and 3 airplanes. The proposed AD would require repetitively inspecting (using visual methods) the internal and external surfaces of the brake torque tube assemblies in the cockpit area for cracks. The proposed AD would also require obtaining and incorporating repair procedures for any brake torque tube assembly found cracked. The proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by the proposed AD are intended to detect and correct cracks in the brake torque tube assemblies, which could result in reduced brake efficiency with possible reduced and/or loss of airplane control.