Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to supersede an existing airworthiness directive (AD) for Bell Helicopter Textron, Inc. (BHTI) Model 204B, 205A, 205A-1, 205B, and 212 helicopters. The existing AD currently requires conducting various inspections associated with the main rotor grip (grip). If a crack is found, that AD requires replacing the grip before further flight. If delamination of the buffer pad on the grip tang inner surface is found, that AD requires inspecting the grip surface for corrosion or other damage and repairing or replacing the grip if corrosion or other damage is found. That AD also requires determining and recording the hours time-in-service (TIS) and the engine start/stop cycles for each grip on a component history card or equivalent record. Additionally, that AD requires you to report certain inspection results to the FAA. Since we issued that AD, additional cracks in grips have been found. Analysis of these events has shown that a retirement life is needed for certain grips, and the AD applicability needs to be expanded to include additional grips similar in design, as well as to include the Model 210 helicopter, which was issued an FAA type certificate after the existing AD was issued. The proposed actions are intended to prevent failure of a grip, separation of a main rotor blade, and subsequent loss of control of the helicopter.