Airworthiness Directive · Amendment 39-13232 · Aerospatiale Model ATR42 Series Airplanes and Model ATR72 Series Airplanes
Aerospatiale Model ATR42 Series Airplanes and Model ATR72 Series Airplanes
Model ATR42-200, -300, -320, and -500 series airplanes; and Model ATR72 series airplanes; certificated in any category; equipped with IPP JANCO Automatic Takeoff Power Control System (ATPCS) test selector switch, part number (P/N) ACE 0002; except those airplanes having received modification 5162 in production and on which no replacement of the ATPCS test selector switch has been performed afterwards.
This amendment adopts a new airworthiness directive (AD), applicable to certain Aerospatiale Model ATR42-200, -300, -320, and - 500 series airplanes; and Model ATR72 series airplanes; that requires replacement of a certain Automatic Takeoff Power Control System (ATPCS) test selector switch with a different test selector switch. This action is necessary to prevent shorting of a contact in the ATPCS test selector switch due to abnormal wear of contact surfaces, which could result in dual engine power drop with associated loss of both alternating current wild and main hydraulic power during ground maneuvers, and consequent reduced controllability of the airplane and increased flightcrew workload. This action is intended to address the identified unsafe condition.
