AD/CFE 738/4 Stage 2 High Pressure Turbine Aft Cooling Plate (Cth)

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 39.001(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.

CFE Company Turbine Engines - CFE 738 Series

AD/CFE 738/4 Stage 2 High Pressure Turbine
Aft Cooling Plate 3/2006

Applicability:

CFE Model CFE738-1-1B turbofan engines, part number (P/N) 3050000-5, with gas generator modules P/N 6091T09G01, serial numbers (SN's) 800421, 800422, 800423, 800424, 800425, 800426, 800427, 800428, 800429, and 800430 installed.

Note 1:  These engines are installed on, but not limited to Dassault-Breguet Falcon 2000 series aeroplanes.

Requirement:

1.    Inspect the stage 2 HPT aft cooling plate for nicks, dents, and scratches on surface D in accordance with the requirements of CFE Alert Service Bulletin (ASB) No. CFE738-A72-8031, Revision 4, dated 27 March 2002, paragraph 2.B.(1).

2.    Repair those stage 2 HPT aft cooling plates with indentation 0.003 inch deep or less in accordance with ASB No. CFE738-A72-8031, Revision 4 paragraph 2.B.(1).

3.    Remove from service before further flight those stage 2 HPT aft cooling plates that have nicks, dents, and/or scratches that exceed the acceptance limits in accordance with ASB No. CFE738-A72-8031, paragraph 2.B.(1), and replace with serviceable parts.

4.    Inspect the stage 2 HPT rotor disk post aft mating surface for raised metal, and remove raised metal if present in accordance with ASB No. CFE738-A72-8031, Revision 4, paragraph 2.B.(2).

Note 2:  FAA AD 99-27-16R1 Amdt 39-12791 refers.

Compliance:

Unless previously accomplished, carry out at the next shop visit where the HPT assembly is sufficiently disassembled to afford access to the stage 2 HPT aft cooling plate but not later than 4,500 part cycles-since-new.

This Airworthiness Directive becomes effective on 16 March 2006.

Background: The actions detailed in this AD are intended to prevent stage 2 high pressure turbine (HPT) aft cooling plate failure, which could result in an uncontained engine failure and damage to the aeroplane.

James Coyne
Delegate of the Civil Aviation Safety Authority

1 February 2006