Airworthiness Directives; Eurocopter France Model AS-350B, BA, B1, B2, and D; and AS-355E, F, F1, F2, and N Helicopters

This amendment supersedes an existing airworthiness directive (AD) that applies to Eurocopter France (ECF) Model AS-350B, BA, B1, B2, and D; and AS-355E, F, F1, F2, and N helicopters. That AD currently requires inspecting the main gearbox suspension bi-directional cross beam (cross beam) for cracks, replacing the cross beam if a crack is found, and adding time intervals for repetitive dye-penetrant inspections on cross beams with 5,000 or more hours time-in-service (TIS). This amendment requires the same inspections as the existing AD but would delete repetitive dye-penetrant inspections on cross beams with 5,000 or more hours TIS. This amendment is prompted by the discovery that repetitive dye-penetrant inspections were erroneously required in the existing AD. The actions specified by this AD are intended to prevent failure of the cross beam that could lead to rotation of the main gearbox, severe vibrations, and a subsequent forced landing.