AD/PC-6/49 - Aileron Control System Bellcrank Assembly (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 Porter PC-6 Series Aeroplanes

AD/PC-6/49 Aileron Control System Bellcrank Assembly 1/2003

Applicability: Model PC-6 series aircraft, with all Manufacturers Serial Numbers (MSN) up to and including MSN 939.

Requirement: Action in accordance with Pilatus Aircraft Mandatory Service Bulletin No. 27-001, dated 5 June 2002.

Note: Switzerland FOCA AD HB 2002-642 refers.

Compliance: Within 100 hours time in service or 3 months after 23 January 2003, whichever occurs first.

This Airworthiness Directive becomes effective on 23 January 2003.

Background: The FOCA received a report of an incident of increased friction in the aileron control system of a PC-6 aircaft. Investigation revealed that axial movement in certain aileron bellcrank assemblies can occur in the aileron control system which could result in interference of the control cable attachment bolts with the adjacent structure. The axial movement was found to be caused by deterioration of the bond between the surfaces of the bellcrank bearings and their housings.