AD/PC-12/48 Centre Fuselage Frame 21 (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Pilatus PC-12 Series Aeroplanes

AD/PC-12/48 Centre Fuselage Frame 21 6/2006

Applicability:

Model PC-12 and PC-12/45 aircraft, manufacturer serial numbers 101 through 617.

Requirement:

1.    Perform an inspection of Centre Fuselage Frame 21 (FR21) in the area of the outer sidewall frame attachment lug forward and aft side faces, left and right, to determine if there is any drill damage.

If damage is detected during the Requirement 1 inspection that is less than 0.1 mm (0.004-inch), before further flight, repair the damage in accordance with Pilatus PC-12 Service Bulletin No. 53-004.

If damage is detected during the Requirement 1 inspection that is more than 0.1 mm (0.004-inch), before further flight, contact Pilatus Aircraft Ltd. for technical advice.

2.    Perform an inspection of FR21 in the area of the top surface of the wing upper-attachment lugs, left and right, to determine if there is any drill damage.

If damage is detected during the Requirement 2 inspection that is less than 0.1 mm (0.004-inch), before further flight, repair the damage in accordance with Pilatus PC-12 Service Bulletin No. 53-004.

If damage is detected during the Requirement 2 inspection that is more than 0.1 mm (0.004-inch), before further flight, contact Pilatus Aircraft Ltd. for technical advice.

Note:  FOCA AD HB-2006-223 refers.

Compliance:

Within 12 months after 8 June 2006.

This Airworthiness Directive becomes effective on 8 June 2006.

Background: The Federal Office for Civil Aviation received reports of drill mark damage on some Centre Fuselage Frame 21 lug fittings on the production line, and during a number of mid life wing lug inspections.  The damage to the lug fittings is thought to have occurred during assembly of the aircraft.  Depending on the size and location of damage, the fatigue life of the wing attachment lugs may be affected.

Richard Castles
Delegate of the Civil Aviation Safety Authority

19 April 2006