On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/LYC/90 Amdt 1 and issues the following 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.
Lycoming Piston Engines
AD/LYC/90 Amdt 2
Fuel Injection Supply Lines
All Lycoming Engines fuel injected horizontally opposed piston engines.
1. Inspect all fuel nozzle supply lines between the fuel injector manifold and the fuel injector nozzles for evidence of cracking, corrosion, pitting, physical damage and stains caused by fuel leakage.
2. Replace any fuel nozzle supply line with evidence of cracking, corrosion, pitting, physical damage or stains caused by fuel leakage.
3. Inspect all fuel nozzle supply lines between the fuel injector manifold and the fuel injector nozzles for fitment and integrity of fuel line support clamps, in accordance with the engine manufacturer's published data.
4. Fit or replace as necessary, fuel nozzle supply line support clamps not in accordance with the engine manufacturer's published data.
Note 1: The latest approved revision of Lycoming Mandatory Service Bulletin (MSB) 342 pertains to the subject of this Airworthiness Directive.
Note 2: AD/LYC/90 Amdt 2 is based on FAA Airworthiness Directive (AD)
2011-26-04 Amendment 39-16894, or the latest FAA approved revision, but extends the applicability to all Lycoming fuel injected horizontally opposed piston engines, whilst introducing specific inspection criteria.
Requirement 1 & 3: At the next scheduled maintenance after the affective date of this AD and thereafter, at intervals not exceeding 110 hours time in service.
Requirement 2 & 4: Before further flight, following the inspections in accordance with Requirement 1 & 3 of this Directive.
This Amendment becomes effective on 25 January 2012.
This Directive has been issued, not to reflect a design error or a material fault, but to address inadequate maintenance. The FAA has reports of fatal accidents attributable to fuel injector supply line failure because of the inadequate maintenance.
A review of Australian Service Difficulty Reports (SDRs) has revealed many reports of fuel nozzle supply line defects. The majority of these reports advise of fuel leaks. In each report, there was evidence of inadequate maintenance.
This AD requires inspection and replacement as necessary of the fuel nozzle supply lines and their support clamps to preclude a fuel nozzle supply line failure, which may result in an engine failure or an engine fire event.
The current amendment enhances an existing visual inspection and directs specific attention to inspect for the presence of pitting and corrosion in the fuel nozzle supply line which was determined by ATSB to be the causal factor behind failure of one of the fuel lines. (ATSB Report reference BO/200601291).
The current amendment also makes reference to the latest FAA Airworthiness Directive as well as to Lycoming MSB 342 pertaining to the subject of this AD.
Amendment 2 of this AD refers to FAA AD 2011-26-04 Amendment 39-16894, or the latest FAA approved revision, and is effective on 25 January 2012.
Amendment 1 of this AD became effective on 21 July 2006.
The original issue of this AD became effective on 17 September 1992.
Delegate of the Civil Aviation Safety Authority
6 January 2012