Summary
This document proposes adopting a new airworthiness directive (AD) for MD Helicopters, Inc. (MDHI) Model MD900 series helicopters. The AD would require modifying the pilot and co-pilot dual-control directional pedal assemblies, or the pilot single-control directional pedal assembly (directional control pedal assembly). This proposal is prompted by an accident which has been attributed to loss of directional control due to failure of the welds in the directional control pedal assembly. The actions specified by the proposed AD are intended to prevent fatigue cracking in the welds that connect the directional control pedal to the pedal shaft, resulting in loss of directional control and subsequent loss of control of the helicopter.