AD/Turmo/5 Amdt 4 Centrifugal Compressor (Cth)

AIRWORTHINESS DIRECTIVE

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/TURMO/5 Amdt 3 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.

Turbomeca Turbine Engines - Turmo Series

AD/TURMO/5 Amdt 4 Centrifugal Compressor 5/2005

Applicability:

Turmo IV A and IV C model turboshaft engines installed in Aerospatiale SA 330 F, G and J “Puma” helicopters.

Requirement:

Inspect the centrifugal compressor in accordance with Turbomeca Mandatory Service Bulletin No. A249 72 0100.

Note 1:  DGAC AD F-2005-037 EASA approval No. 2005-1910 dated 22 February 2005 refers, which supersedes DGAC AD 1997-122R3.

Compliance:

Within 50 hours or within 6 months (whichever occurs first) from the effective date with the following frequency:

• At intervals not to exceed 200 flight hours if the engine has no TU 191, TU 197, TU 215 and TU224 modifications; or
• At intervals not to exceed 750/K flight hours if the engine is equipped with TU 197 or TU 215 modifications; or
• At intervals not to exceed 1,000 flight hours if the engine is equipped with TU 191 or TU 224 modifications.

Note 2:  The value of K is determined by the calculations given in Turbomeca Mandatory Service Bulletin No. A249 72 0100.

This Amendment becomes effective on 12 May 2005.

Background:

This Directive is in response to reports of engine power loss and in-flight shut down events resulting from the release of compressor wheel fragments.  This Directive requires the inspection of the centrifugal compressor.

This amendment requires different inspection intervals to be followed based upon the modification status of the engine.

Amendment 3 was issued in response to the latest revision of the reference document and became effective 10 August 2000.

Amendment 2 was issued to amend the inspection frequency of this Directive became effective 17 June 1999.

Amendment 1 was issued to reflect the latest revision to the reference document and became effective 25 February 1999.

The original issue of this Directive became effective 14 August 1997.

James Coyne
Delegate of the Civil Aviation Safety Authority

31 March 2005