Summary
This document proposes superseding an existing airworthiness directive (AD) that applies to Eurocopter France (Eurocopter) Model EC 155B, SA-365N and N1, AS-365N2, and AS 365 N3 helicopters. That AD currently requires inspecting the hydraulic brake hose (hose) for crazing, pinching, distortion, or leaks at the torque link hinge and replacing the hose, if necessary. That AD also requires inspecting the hose and the emergency flotation gear pipe to ensure adequate clearance, and adjusting the landing gear leg, if necessary. This action would require the same actions as the existing AD and would add a model to the applicability. This proposal is prompted by notification by the manufacturer and the European Authority that another affected model helicopter, the Model EC155B1, may have the same unsafe condition and should be added to the existing AD. The actions specified by the proposed AD are intended to prevent failure of a hose, resulting in failure of hydraulic pressure to thebrakes on the affected landing gear wheel, and subsequent loss of control of the helicopter during a run-on landing.