Airworthiness Directive · Amendment 39-13210 · Rolls-Royce Corporation (Formerly Allison Engine Company, Allison Gas Turbine Division, and Detroit Diesel Allison) Models 250-C30R/3, -C30R/3M, -C47B, and -C47M Turboshaft Engines
Rolls-Royce Corporation (Formerly Allison Engine Company, Allison Gas Turbine Division, and Detroit Diesel Allison) Models 250-C30R/3, -C30R/3M, -C47B, and -C47M Turboshaft Engines
Superseded. A later AD replaced this one: AD 2004-24-04. Comply with the one in force.
This AD is applicable to Rolls-Royce Corporation (formerly Allison Engine Company, Allison Gas Turbine Division, and Detroit Diesel Allison) models 250-C30R/3, -C30R/3M, -C47B, and -C47M turboshaft engines. These engines are installed on, but not limited to, Bell OH-58D, Bell Helicopter Textron 407, Boeing AH/MH-6M, and MD Helicopters Inc. 600N helicopters.
The FAA is adopting a new airworthiness directive (AD) for Rolls-Royce Corporation (formerly Allison Engine Company, Allison Gas Turbine Division, and Detroit Diesel Allison) models 250-C30R/3, -C30R/ 3M, -C47B, and -C47M turboshaft engines. This AD requires initial and repetitive electrical signal inspections of the hydromechanical unit (HMU) Power Lever Angle (PLA) potentiometer. This AD is prompted by an investigation by the National Transportation Safety Board (NTSB), which revealed that a potential undetected failure of the PLA potentiometer electrical signal could cause uncommanded and sudden changes in engine power. The actions specified in this AD are intended to prevent uncommanded and sudden changes in engine power.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Engines