Federal Register of Legislation - Australian Government

Primary content

AD/AL 250/91 Amdt 2 Airworthiness Directives as made
This instrument repeals and replaces the previous Airworthiness Directive on this subject to incorporate changes to add compressor module C47 serial number CAC44094.
Administered by: Infrastructure, Transport, Regional Development and Communications
Exempt from sunsetting by the Legislation (Exemptions and Other Matters) Regulation 2015 s12 item 15
Registered 06 May 2020
Tabling HistoryDate
Tabled HR12-May-2020
Tabled Senate12-May-2020

AIRWORTHINESS DIRECTIVE

On the commencement date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below repeals Airworthiness Directive (AD) AD/AL 250/91 Amdt 1 and issues the following AD under subregulation 39.001 (1) of CASR and subsection 33 (3) of the Acts Interpretation Act 1901. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct an 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.

Rolls-Royce (Allison) Turbine Engines - 250 Series

AD/AL 250/91 Amdt 2

Engine Compressor Module - Removal
from Service

10/2020

 

Applicability:

All Rolls-Royce Allison 250 series engines.

Requirement:

1.     Review engine logbooks and determine if a compressor module with a serial number listed in Table 1 and 2 is installed in the engine.

2.     Remove affected Rolls-Royce Allison C20B series and C20R series compressor modules with a serial number listed in Table 1 from service.

3.     Remove affected Rolls-Royce Allison C18 series, C28 series, C30 series and C47 series compressor modules with a serial number listed in Table 2 from service.

4.     All affected Rolls-Royce Allison C20B series and C20R series compressor modules must be sent to an approved maintenance organisation to be assessed in accordance with Original Equipment Manufacturer (OEM) specifications.

Compressor rotor wheels in the position numbers listed in Table 1 for a module with a serial number listed in Table 1 must be replaced before returning the compressor module to service, the subject removed rotor wheels must be quarantined or scrapped so they cannot be installed as a serviceable part.

5.     All affected Rolls-Royce Allison C18 series, C28 series, C30 series and C47 series compressor modules must be sent to an approved maintenance organisation to be assessed in accordance with OEM specifications.

Compressor impellers must be replaced, or may only be returned to service through an approved OEM repair scheme before returning the compressor module to service. Impellers deemed as not recoverable must be quarantined or scrapped so they cannot be installed as a serviceable part.

Table 1: Affected C20B and C20R compressor modules.

Affected Compressor Module Serial Numbers (S/N):

C20B series

C20R series

Module S/N:

Compressor Rotor Wheel Position Number:

Module S/N:

Compressor Rotor Wheel Position Number:

CAC23900

1, 2, 3 & 4

CAC15280

1

Table 1 (Continued)

Module S/N:

Compressor Rotor Wheel Position Number:

Module S/N:

Compressor Rotor Wheel Position Number:

CAC30243

CAC30972

CAC31261F

CAC31394

CAC32128

CAC33247

CAC33931

CAC34205

CAC35463

CAC36132

CAC37795

CAC37814

CAC37978

CAC38521

CAC39053

CAC40090

CAC40093

CAC40446

CAC40483

CAC40560

CAC41262

CAC41846

CAC41917

CAC42465

CAC43498

1

1

1

To be advised (TBA).

2, 3 & 4

1 & 6

1 & 2

TBA.

4

2, 3, 4, & 6

1

1, 2, 3, 4 & 5

1

TBA.

TBA.

1

1

TBA.

TBA.

1 & 5

1

TBA.

1

1 & 4

1 & 5

CAC15850

CAC15973

CAC28209

1 & 4

1 & 4

3 & 4

Table 2: Affected C18, C28, C30 and C47 compressor modules.

Affected Compressor Module Serial Numbers (S/N):

C18 series

C28 series

C30 series

C47 series

CAC21705B

CAC28017

CAC28022

CAC28048

CAC28119

CAC70026

CAC70243

CAC70779

CAC28046

CAC90011

CAC90052

CAC90069

CAC90507

CAC90719

CAC91119

CAC91305

CAC91311

CAC91507

 

CAC44094

CAC44293

CAC44294

CAC45072

CAC45750

Table 2 (Continued)

C18 series

C28 series

C30 series

C47 series

 

 

CAC91607

CAC91623

CAC91635

CAC91820

CAC98516

CAC98537

 

Compliance:

1.    Before further flight.

2.    For C20B and C20R series compressor modules: Before further flight.

3.    For C18, C28, C30 and C47 series compressor modules: the earlier of the following:

(i)    within 50 hours’ time in service;

(ii)   12 April 2020;

(iii)  next engine shop visit.

(iv)  for C47 compressor module Serial Number CAC44094, within 50 hours’ time in service or 4 June 2020.

4.    Before returning to service.

5.    Before returning to service.

            For aircraft located away from a maintenance facility, a special flight permit may be issued for one non-revenue ferry flight to return the aircraft to the nearest maintenance facility to carry out the requirements of this AD.

            CASA is to be notified of any engines found to have an affected module fitted via the Defect Reporting Service.

Note 1: Civil Aviation Authority of New Zealand (CAA NZ) Airworthiness Directive DCA/AL250/60A has been referenced as a source document for Tables 1 and 2.

Note 2: The primary safety concern with C18, C28, C30 and C47 series compressor modules relates to unauthorised drilling of compressor impellers for balancing.

Note 3: The primary safety concern with C20B and C20R series compressor modules relates to blending repairs on compressor rotor wheels with the lack of shot peening.

 

This AD commences on 8 May 2020.

Background:

A recent audit of a New Zealand maintenance organisation by CAA NZ has determined that compressor module inspections and repairs of these modules may not have been carried out in accordance with approved Rolls-Royce procedures.

 

 

 

Amendment 1 adds the C18 series compressor module, introduces additional serial numbers to each module series and makes minor editorial changes throughout the text.

Amendment 2 adds C47 series compressor module serial number CAC44094, with compliance action time of 50 hours’ time in Service or 4 June 2020.

A drawing of a face

Description automatically generated

Pieter van Dijk
Delegate of the Civil Aviation Safety Authority

4 May 2020