Summary
This document proposes adopting a new airworthiness directive (AD) for Robinson Model R22, R22 Alpha, R22 Beta, and R22 Mariner helicopters, and Model R44 and R44 II helicopters. The AD would require visually inspecting each tail rotor (T/R) control pedal bearing block support (support) for a crack, measuring the thickness of each uncracked support, installing support safety tabs on certain supports, and replacing supports of a certain thickness during overhaul. This proposal is prompted by two reports of Model R22 helicopters experiencing broken supports during flight, which resulted in the T/R control pedals becoming jammed. The actions specified by the proposed AD are intended to prevent the supports from breaking, which can bind the T/R control pedals, resulting in a reduction of yaw control and subsequent loss of control of the helicopter.