Summary
We propose to adopt a new airworthiness directive (AD) for certain Eurocopter France Model AS350 helicopters. This proposed AD is prompted by an in-flight fire caused by ignition of hydraulic fluid leaking from a damaged forward (pitch) servo-control hydraulic hose. The proposed actions are intended to prevent the forward servo-control hydraulic hoses from becoming damaged and leaking hydraulic fluid that could ignite in flight, which can result in loss of main rotor control, power loss, structural damage, propagation of fire, and subsequent loss of control of the helicopter.