AD/HILLER 12/43 - Control System Linkage (Cth)

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

Hiller UH-12 Series Helicopters

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.

AD/HILLER 12/43 Control System Linkage 3/2001

Applicability: Model UH-12, UH-12A, UH-12B, UH-12C, UH-12D, UH-12E, UH-12E-L, UH-12L, and UH-12L4 helicopters.

Requirement: Replace all undrilled-shank bolts at pivoting joints in the control system linkage with drilled-shank bolts, and install castellated nuts and cotter pins in accordance with Hiller Aircraft Corporation Service Bulletin No. 10-4, Revision 2, dated December 20, 1999.

Note: FAA AD 2000-24-21 Amendment 39-12028 refers.

Compliance: At the next annual inspection or within 12 months after 22 March 2001, whichever occurs first, unless already accomplished.

This Airworthiness Directive becomes effective on 22 March 2001.

Background: The FAA received a report of an accident caused by separation of the control system linkage of a Model UH-12E helicopter. The actions specified by this Directive are intended to prevent separation of the control system attachments at pivoting joints, and subsequent loss of control of the helicopter.