AD/SF340/93 - Engine Bottom Mounts (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Safety 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 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.

SAAB SF340 Series Aeroplanes

AD/SF340/93 Engine Bottom Mounts 7/2003

Applicability: Model SF340A aircraft, serial numbers 004 through 159.

Model 340B aircraft, serial numbers 160 through 459.

Requirement: Action in accordance with Saab Aircraft Mandatory Service Bulletin 340-71-059, dated 16 May 2003.

Note: LFV AD 1-192 refers.

Compliance: Within 500 flight hours after 10 July 2003.

This Airworthiness Directive becomes effective on 10 July 2003.

Background: The engine bottom mounts molded assembly part number 00-13226-03 with certain cure dates, have exhibited de-bonding of the elastomer from the metal inner core and shim after a few hundred hours of operation. This de-bonding will reduce the redundancy and change the stiffness and damping characteristics of the engine support system, causing heavy chafing on the nacelle structure and chafing of the fire sensor loop.

David Villiers Delegate of the Civil Aviation Safety Authority 30 May 2003