AD NUMBER: 2003-13-10
MANUFACTURER: Rolls Royce SUBJECT: Airworthiness Directive 2003-13-10
SUMMARY: CORRECTION - 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 hydro-mechanical 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.