Summary
This document proposes the adoption of a new airworthiness directive (AD) for MD Helicopters, Inc. (MDHI) Model MD-900 helicopters. The AD would require modifying the non-rotating swashplate assembly and re-identifying it and the swashplate assembly with a new part number (P/N). The AD would also require creating a component history card or equivalent record to track the life of the newly identified non-rotating swashplate assembly and establishing a life limit of 1800 hours time-in-service (TIS). In addition, the AD would require inspecting and modifying, if necessary, the longitudinal drive link assembly. This proposal is prompted by reports of damage to the longitudinal drive link assembly caused by the sharp inner edge of the bushing in the non-rotating swashplate assembly. The actions specified by the proposed AD are intended to prevent damage to the longitudinal drive link, loss of control of the main rotor system, and subsequent loss of control of the helicopter.