Document ID: chunk:federal_register_of_legislation:F2020L00555:body:0:p1
Version: federal_register_of_legislation:F2020L00555
Segment Type: other
Provision Reference: 
Character Range: 0–3434

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  10/2020
                     from Service

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     1                                        CAC15850     1 & 4
                CAC30972     1                                        CAC15973     1