COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Piper PA-31 Series Aeroplanes
AD/PA-31/110
Amdt 3
Emergency Electrical Fuel Pumps 12/90
Applicability: All models PA-31, PA31-300, PA-31-325, PA-31-350, PA-31P-350 and PA-31-
350T1020, fitted with emergency fuel pumps part nos 42113-02, 42113-05 and 42113-06.
Requirement: a. Recondition the emergency fuel pumps, and in addition replace the blade retaining rings; in accordance with the aircraft manufacturer’s Maintenance Manual, or
b. Replace the emergency fuel pumps blade retaining rings in accordance with the aircraft manufacturer’s Maintenance Manual.
Compliance: Within 2000 hours aircraft time in service since new or reconditioned, thereafter at intervals of 2000 hours aircraft time in service, or for those fuel pumps which have achieved more than 2000 hours aircraft time in service after 28 February 1986, within 100 hours aircraft time in service after 31 March 1986, and thereafter at intervals of 2000 hours aircraft time in service.
Background: Reports have been received of loss of engine power caused initially by the failure of the emergency fuel pump blade retention ring. Pieces of the ring travel through the fuel system and lodge in the engine driven fuel pump, causing it to fail.
Amendment 2 is raised to allow replacement of the fuel pump retaining ring without overhauling the pump and to extend compliance. Loss of the emergency pump will not affect overall system safety, provided the retaining ring is intact.