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-31/124 Wing Spar Splice Plate (Chieftain) 13/94 DM
Applicability: All Piper Chieftain PA-31-350, PA31-350/A1 AND PA31-350/A2.
Requirement: Remove from service the splice plate which joins the wing main spar lower cap at the aircraft centre line, in accordance with compliance below.
Report as a major defect any fretting, corrosion or crack found in the splice plate upon removal.
Attach a tag to the splice plate marked:
Attention: Fatigue Section Airworthiness Branch Canberra
On the same tag, identify the aircraft registration and splice plate time in service.
Send all splice plates removed in accordance with this Directive to the nearest CAA Airworthiness Office.
Compliance: 1. Subject to paragraphs 2., 3., and 4. below, remove from service splice plates which have achieved 13000 hours time in service (TIS), or 2000 hours TIS after the splice plate was inspected as part of the Gippsland Aeronautics main spar modification (see AD/PA-31/37), whichever is the later.
2. For splices plate that have exceeded the above limit by less than 1000 hours, as at 31 October 1994, remove before 31 January 1995.
3. For splice plates that have exceeded the above limit by between 1000 and 3000 hours, as at 31 October 1994, remove before 31 December 1994.
4. For splice plates that have exceeded the above limit by more than 3000 hours, as of 31 October 1994, remove before 30 November 1994.
Background: Fretting has caused fatigue cracking in PA-31 Navajos.
Although the PA-31-350 design in this area is an improvement over the PA-31, fretting has been found. This requires control action for those aircraft that have had their spar life extended without replacement of the splice plate.