AD/PC-12/30 - MLG Hydraulic Actuator Special Bolts (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

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 39.1 (1) of CAR 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-12/30 MLG Hydraulic Actuator Special Bolts 13/2001 DM

Applicability: Model PC-12 and PC-12/45 aircraft, serial numbers MSN 349, MSN 352, MSN 357, MSN 359, MSN 362 through MSN 365, MSN 367, MSN 369, MSN 371, MSN 375, MSN 377, MSN 380, MSN 384, MSN 385, MSN 388, MSN 390, MSN 391, MSN 393, MSN 401, and MSN 409.

Requirement: Inspect in accordance with Pilatus Aircraft Service Bulletin No. 30-012, dated 18 October 2001.

Note: FOCA AD HB 2001-603 refers.

Compliance: At the next scheduled 100 hour inspection or within 30 days after 21 November 2001, whichever occurs first.

This Airworthiness Directive becomes effective on 21 November 2001.

Background: It has been found on some PC-12/45 aircraft that special bolts connecting the hydraulic actuators to the main landing gear assemblies have the potential to fail during operation. Investigation revealed that the problem is caused by an improper cadmium plating process applied to the high strength steel part, which can cause hydrogen embrittlement.