Summary
We propose to adopt a new airworthiness directive (AD) for certain Eurocopter Deutschland GmbH (Eurocopter) Model EC135P2+ and EC135T2+ helicopters. This proposed AD would require inspecting the mechanical air conditioning system compressor bearing block upper bearing (upper bearing) for corrosion, leaking grease, condensation, or water. This proposed AD is prompted by metallic debris from an upper bearing found in the air inlet areas of both engines in a Model EC135P2+ helicopter. The proposed actions are intended to prevent metallic debris from damaging the engine, causing loss of engine power, and subsequent loss of helicopter control.