Commonwealth legislation

AD/AL 250/91 Amdt 2 Engine Compressor Module - Removal from Service

In ForceCTH

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

6/10 complexity

Requires operators of all Rolls‑Royce (Allison) 250‑series engines to check logbooks for listed compressor‑module serial numbers and remove affected modules from service. C20B/C20R modules must go to an approved maintenance organisation and have specified rotor wheels replaced and quarantined; C18/C28/C30/C47 modules must be assessed by an approved maintenance organisation and have impellers replaced or returned only under an OEM repair scheme. Compliance times vary (some before next flight; others within 50 hours, set dates, or next shop visit).

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5,156 words · generated 12/06/2026

What it does

This Civil Aviation Safety Authority airworthiness directive (AD/AL 250/91 Amdt 2, dated 4 May 2020, commencing 8 May 2020) requires operators of Rolls‑Royce Allison 250 series engines to identify and remove specified compressor modules from service, and to have those modules assessed and, where required, repaired or have specific compressor components replaced before the engine is returned to service. The AD applies to all Rolls‑Royce Allison 250 series engines (Applicability). The directive sets out five core actions under the heading Requirement: review engine logbooks for specified compressor module serial numbers listed in Table 1 and Table 2; remove affected C20B and C20R compressor modules; remove affected C18, C28, C30 and C47 compressor modules; send affected C20B/C20R modules to an approved maintenance organisation for OEM‑specification assessment and replace specified compressor rotor wheels before returning to service, with the removed rotor wheels quarantined or scrapped; and send affected C18/C28/C30/C47 modules to an approved maintenance organisation for OEM assessment, with compressor impellers either replaced or returned to service only through an approved OEM repair scheme, and any unrecoverable impellers quarantined or scrapped.

Compliance timing is explicit and series‑dependent (Compliance). For all affected modules the overarching requirement is to act before further flight in some cases. For C20B and C20R series the compliance requirement is "Before further flight". For C18/C28/C30/C47 series the AD prescribes the earlier of: within 50 hours time in service, 12 April 2020, or the next engine shop visit, with a specific serial number CAC44094 subject to 50 hours or 4 June 2020. The AD permits a single non‑revenue ferry flight to the nearest maintenance facility for aircraft located away from a maintenance facility. It also directs that CASA be notified of any engines found to have an affected module fitted via the Defect Reporting Service.

Current sections

Direct links to the current provisions in AD/AL 250/91 Amdt 2 Engine Compressor Module - Removal from Service.

Rolls-Royce (Allison) Turbine Engines -

Rolls-Royce (Allison) Turbine Engines - 250 Series

AD/AL 250/91 Amdt 2	Engine Compressor Module - Removalfrom Service	10/2020

<table cellspacing="0" cellpadding="0" style="width:510.3pt; margin-top:0pt; margin-bottom:0pt; border-collapse:collapse"><tbody><tr><td style="width:74.35pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>Applicability:</span></p></td><td style="width:414.55pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>All Rolls-Royce Allison 250 series engines.</span></p></td></tr><tr><td style="width:74.35pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>Requirement:</span></p></td><td style="width:414.55pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>1.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>Review engine logbooks and determine if a compressor module with a serial number listed in Table 1 and 2 is installed in the engine.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>2.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>Remove affected Rolls-Royce Allison C20B series and C20R series compressor modules with a serial number listed in Table 1 from service.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>3.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>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.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>4.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>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.</span></p><p style="margin-left:22.65pt"><span>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.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>5.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>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</span><span>.</span></p><p style="margin-left:22.65pt; text-indent:-1.4pt"><span>Compressor impellers must be </span><span>replaced, or</span><span> may only be returned to service through an approved OEM repair scheme </span><span>before returning the compressor module to service. Impellers deemed as not recoverable </span><span>must </span><span>be quarantined or </span><span>scrapped so they cannot be installed as a serviceable part.</span></p><p style="text-align:center"><span>Table 1: Affected C20B and C20R compressor modules.</span></p><table cellspacing="0" cellpadding="0" style="margin-top:0pt; margin-bottom:0pt; border:0.75pt solid #000000; border-collapse:collapse"><tbody><tr><td colspan="4" style="width:403pt; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">Affected Compressor Module Serial Numbers (S/N):</span></p></td></tr><tr><td colspan="2" style="width:216.05pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C20B series</span></p></td><td colspan="2" style="width:176.15pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C20R series</span></p></td></tr><tr><td style="width:81.4pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:123.85pt; border:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td><td style="width:72.7pt; border:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td></tr><tr style="height:23.35pt"><td style="width:81.4pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC23900</span></p></td><td style="width:123.85pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1, 2, 3 &amp; 4</span></p></td><td style="width:72.7pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC15280</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p></td></tr></tbody></table><p style="margin-top:12pt; text-align:center"><span>Table 1 (Continued)</span></p><table cellspacing="0" cellpadding="0" style="margin-top:0pt; margin-bottom:0pt; border:0.75pt solid #000000; border-collapse:collapse"><tbody><tr><td style="width:81.4pt; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:123.85pt; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td><td style="width:74.25pt; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:91.1pt; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td></tr><tr style="height:349.85pt"><td style="width:81.4pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC30243</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC30972</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC31261F</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC31394</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC32128</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC33247</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC33931</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC34205</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC35463</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC36132</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC37795</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC37814</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC37978</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC38521</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC39053</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40090</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40093</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40446</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40483</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40560</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC41262</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC41846</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC41917</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC42465</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC43498</span></p></td><td style="width:123.85pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">To be advised (TBA).</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">2, 3 &amp; 4</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 6</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 2</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">4</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">2, 3, 4, &amp; 6</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1, 2, 3, 4 &amp; 5</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 5</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 4</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 5</span></p></td><td style="width:74.25pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC15850</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC15973</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC28209</span></p></td><td style="width:91.1pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 4</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 4</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">3 &amp; 4</span></p></td></tr></tbody></table><p style="text-align:center"><span>Table 2: Affected C18, C28, C30 and C47 compressor modules.</span></p><table cellspacing="0" cellpadding="0" style="margin-top:0pt; margin-bottom:0pt; border:0.75pt solid #000000; border-collapse:collapse"><tbody><tr><td colspan="4" style="width:403pt; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">Affected Compressor Module Serial Numbers (S/N):</span></p></td></tr><tr><td style="width:92.65pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C18 series</span></p></td><td style="width:92.65pt; border:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C28 series</span></p></td><td style="width:92.65pt; border:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C30 series</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C47 series</span></p></td></tr><tr style="height:142pt"><td style="width:92.65pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif; font-weight:bold">CAC21705B</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC28017</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC28022</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC28048</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC28119</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC70026</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC70243</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC70779</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC28046</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC90011</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC90052</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC90069</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC90507</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC90719</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91119</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91305</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91311</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91507</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt"><span style="font-family:'Times New Roman', serif"></span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC44094</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC44293</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC44294</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC45072</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC45750</span></p></td></tr></tbody></table><p style="margin-top:12pt; text-align:center"><span>Table 2 (Continued)</span></p><table cellspacing="0" cellpadding="0" style="margin-top:0pt; margin-bottom:0pt; border:0.75pt solid #000000; border-collapse:collapse"><tbody><tr><td style="width:92.65pt; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">C18 series</span></p></td><td style="width:92.65pt; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">C28 series</span></p></td><td style="width:92.65pt; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">C30 series</span></p></td><td style="width:92.65pt; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">C47 series</span></p></td></tr><tr style="height:94.4pt"><td style="width:92.65pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold"></span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif"></span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91607</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91623</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91635</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC91820</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC98516</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC98537</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif; font-weight:bold"></span></p></td></tr></tbody></table><p class="Note"></p></td></tr><tr><td style="width:74.35pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>Compliance:</span></p></td><td style="width:414.55pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p style="margin-left:21.6pt; text-indent:-21.6pt"><span>1.</span><span style="width:12.6pt; text-indent:0pt; display:inline-block"> </span><span>Before further flight</span><span>.</span></p><p style="margin-left:21.6pt; text-indent:-21.6pt"><span>2.</span><span style="width:12.6pt; text-indent:0pt; display:inline-block"> </span><span>For C20B and C20R series </span><span>compressor modules: Before further flight.</span></p><p style="margin-left:21.6pt; text-indent:-21.6pt"><span>3.</span><span style="width:12.6pt; text-indent:0pt; display:inline-block"> </span><span>For </span><span>C18, </span><span>C28, C30 and C47 series </span><span>compressor modules: the earlier of the following:</span></p><p style="margin-left:43.2pt; text-indent:-21.6pt"><span>(</span><span>i</span><span>) </span><span style="width:7.27pt; text-indent:0pt; display:inline-block"></span><span>within 50 hours’ time in service;</span></p><p style="margin-left:43.2pt; text-indent:-21.6pt"><span>(ii) </span><span style="width:3.94pt; text-indent:0pt; display:inline-block"></span><span>12 April 2020;</span></p><p style="margin-left:43.2pt; text-indent:-21.6pt"><span>(iii)</span><span style="width:3.61pt; text-indent:0pt; display:inline-block"> </span><span>next engine shop visit.</span></p><p style="margin-left:43.2pt; text-indent:-21.6pt"><span>(iv)</span><span style="width:4.27pt; text-indent:0pt; display:inline-block"> </span><span>for C47 compressor module Serial </span><span>Number</span><span> CAC44094, within 50 hours’ time in service or 4 June 2020.</span></p><p style="margin-left:21.6pt; text-indent:-21.6pt"><span>4.</span><span style="width:12.6pt; text-indent:0pt; display:inline-block"> </span><span>Before returning to service.</span></p><p style="margin-left:21.6pt; text-indent:-21.6pt"><span>5.</span><span style="width:12.6pt; text-indent:0pt; display:inline-block"> </span><span>Before returning to service.</span></p><p style="margin-left:0.3pt; text-indent:-0.3pt"><span style="width:0.3pt; text-indent:0pt; display:inline-block"></span><span>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.</span></p><p style="margin-left:0.3pt; text-indent:-0.3pt"><span style="width:0.3pt; text-indent:0pt; display:inline-block"></span><span>CASA </span><span>is to be notified </span><span>of any engines found to have an affected module fitted</span><span> via the Defect Reporting Service.</span></p><p style="margin-left:0.3pt; text-indent:-0.3pt"><span style="font-style:italic">Note</span><span style="font-style:italic"> 1: </span><span style="font-style:italic">Civil Aviation Authority of New Zealand (CAA NZ) Airworthiness Directive DCA/AL250/60A has been referenced as a source document for Table</span><span style="font-style:italic">s</span><span style="font-style:italic"> 1</span><span style="font-style:italic"> and 2</span><span style="font-style:italic">.</span></p><p style="margin-left:0.3pt; text-indent:-0.3pt"><span style="font-style:italic">Note 2: </span><span style="font-style:italic">The primary safety concern with C18, C28, C30 and C47 series compressor modules relates to unauthorised drilling of compressor impellers for balancing.</span></p><p><span style="font-style:italic">Note 3: </span><span style="font-style:italic">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.</span></p></td></tr><tr><td style="width:74.35pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span></span></p></td><td style="width:414.55pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>Th</span><span>is</span><span> </span><span>AD </span><span>commences on</span><span> 8 May 2020.</span></p></td></tr><tr><td style="width:74.35pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>Background:</span></p></td><td style="width:414.55pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>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.</span></p></td></tr></tbody></table>

	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

AD/AL 250/91 Amdt 2

Engine Compressor Module - Removalfrom S

Engine Compressor Module - Removalfrom Service

Engine Compressor Module - Removal

from Service

10/2020

Source text: opening excerpt

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

Rolls-Royce (Allison) Turbine Engines - Rolls-Royce (Allison) Turbine Engines - 250 Series

Rolls-Royce (Allison) Turbine Engines - 250 Series

AD/AL 250/91 Amdt 2	Engine Compressor Module - Removalfrom Service	10/2020

<table cellspacing="0" cellpadding="0" style="width:510.3pt; margin-top:0pt; margin-bottom:0pt; border-collapse:collapse"><tbody><tr><td style="width:74.35pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>Applicability:</span></p></td><td style="width:414.55pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>All Rolls-Royce Allison 250 series engines.</span></p></td></tr><tr><td style="width:74.35pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p><span>Requirement:</span></p></td><td style="width:414.55pt; padding-right:5.35pt; padding-left:5.35pt; vertical-align:top"><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>1.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>Review engine logbooks and determine if a compressor module with a serial number listed in Table 1 and 2 is installed in the engine.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>2.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>Remove affected Rolls-Royce Allison C20B series and C20R series compressor modules with a serial number listed in Table 1 from service.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>3.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>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.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>4.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>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.</span></p><p style="margin-left:22.65pt"><span>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.</span></p><p style="margin-left:22.65pt; text-indent:-22.65pt"><span>5.</span><span style="width:13.65pt; text-indent:0pt; display:inline-block"> </span><span>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</span><span>.</span></p><p style="margin-left:22.65pt; text-indent:-1.4pt"><span>Compressor impellers must be </span><span>replaced, or</span><span> may only be returned to service through an approved OEM repair scheme </span><span>before returning the compressor module to service. Impellers deemed as not recoverable </span><span>must </span><span>be quarantined or </span><span>scrapped so they cannot be installed as a serviceable part.</span></p><p style="text-align:center"><span>Table 1: Affected C20B and C20R compressor modules.</span></p><table cellspacing="0" cellpadding="0" style="margin-top:0pt; margin-bottom:0pt; border:0.75pt solid #000000; border-collapse:collapse"><tbody><tr><td colspan="4" style="width:403pt; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">Affected Compressor Module Serial Numbers (S/N):</span></p></td></tr><tr><td colspan="2" style="width:216.05pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C20B series</span></p></td><td colspan="2" style="width:176.15pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p style="text-align:center"><span style="font-weight:bold">C20R series</span></p></td></tr><tr><td style="width:81.4pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:123.85pt; border:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td><td style="width:72.7pt; border:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td></tr><tr style="height:23.35pt"><td style="width:81.4pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC23900</span></p></td><td style="width:123.85pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1, 2, 3 &amp; 4</span></p></td><td style="width:72.7pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC15280</span></p></td><td style="width:92.65pt; border-top:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p></td></tr></tbody></table><p style="margin-top:12pt; text-align:center"><span>Table 1 (Continued)</span></p><table cellspacing="0" cellpadding="0" style="margin-top:0pt; margin-bottom:0pt; border:0.75pt solid #000000; border-collapse:collapse"><tbody><tr><td style="width:81.4pt; border-right:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:123.85pt; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td><td style="width:74.25pt; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Module S/N:</span></p></td><td style="width:91.1pt; border-left:0.75pt solid #000000; border-bottom:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p><span style="font-weight:bold">Compressor Rotor Wheel Position Number:</span></p></td></tr><tr style="height:349.85pt"><td style="width:81.4pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC30243</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC30972</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC31261F</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC31394</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC32128</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC33247</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC33931</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC34205</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC35463</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC36132</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC37795</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC37814</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC37978</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC38521</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC39053</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40090</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40093</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40446</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40483</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC40560</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC41262</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC41846</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC41917</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC42465</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">CAC43498</span></p></td><td style="width:123.85pt; border-top:0.75pt solid #000000; border-right:0.75pt solid #000000; border-left:0.75pt solid #000000; padding-right:5.03pt; padding-left:5.03pt; vertical-align:top"><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">To be advised (TBA).</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">2, 3 &amp; 4</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 6</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 2</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">4</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">2, 3, 4, &amp; 6</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1, 2, 3, 4 &amp; 5</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">TBA.</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt; font-size:12pt"><span style="font-family:'Times New Roman', serif">1 &amp; 5</span></p><p class="Bodytext" style="margin-left:0pt; margin-bottom:0pt; text-indent:0pt;

The AD sets a sequential, documentable compliance workflow. The following steps follow the AD’s Requirements and Compliance paragraphs and translate them into an operational checklist. Each required action should be documented in maintenance records showing who performed the action, when, and what the outcome was.

Immediate logbook review. Per Requirement 1, review all engine logbooks for the presence of compressor module serial numbers listed in Table 1 (C20B/C20R) and Table 2 (C18, C28, C30, C47). Record the findings, including engine serial number, module serial number, installation date and hours in service. If logbooks are incomplete or missing, escalate to trace parts history via maintenance records and owners.
If an affected module is fitted, remove the module from service. For serial numbers listed in Table 1 and Table 2, Requirements 2 and 3 require removal from service. For C20B/C20R modules this must be done "Before further flight" (Compliance 2). For C18/C28/C30/C47 modules act per the earlier‑of rule in Compliance 3: within 50 hours' time in service, by 12 April 2020, or at next engine shop visit, except serial CAC44094 where the deadline is within 50 hours TIS or 4 June 2020.
Arrange one ferry flight only if necessary. If the aircraft is located away from an approved maintenance facility, arrange a special flight permit for one non‑revenue ferry flight to the nearest maintenance facility. Ensure the ferry flight is non‑revenue and that all operational and airworthiness conditions for the permit are satisfied.
Transfer the module to an approved maintenance organisation. For all affected modules the AD requires transfer to an approved maintenance organisation that can assess the module "in accordance with OEM specifications" (Requirements 4 and 5). Confirm the AMO’s approval scope and their capability to carry out OEM‑level assessment and to perform or coordinate OEM repair schemes where required.
Component‑level actions at AMO. For C20B/C20R modules follow Requirement 4: have the AMO assess the module to OEM specifications, and replace the compressor rotor wheels in the positions listed in Table 1 for that module serial number before returning the module to service. For C18/C28/C30/C47 modules follow Requirement 5: impellers must be replaced or can only be returned to service through an approved OEM repair scheme. The AMO must determine recoverability under OEM criteria.
Quarantine and disposal. Remove and either quarantine or scrap subject rotor wheels and impellers that are not returned to service, as required by Requirements 4 and 5. Maintain chain‑of‑custody records that demonstrate quarantine/scrap steps and ensure scrapped parts cannot be reintroduced as serviceable.
Documentation and certification of assessment/repairs. Obtain written evidence from the AMO that assessment and any repairs or replacements were completed in accordance with OEM specifications. Ensure maintenance release paperwork, certification, and part replacement records are appended to the engine and aircraft maintenance records.
CASA notification. Notify CASA via the Defect Reporting Service of any engines found to have an affected module fitted. Record the notification reference in your maintenance file.
Re‑entry to service only after OEM‑compliant assessment. Do not return the module to service, or the aircraft to commercial operation, until the AMO has completed the OEM assessment and any required replacements or OEM repair scheme actions. For modules where the AD requires "Before further flight", the aircraft must not fly with the affected module installed until compliant.
Monitor for amendments and TBA table entries. Because Table 1 contains "TBA" entries and the AD has been amended at least twice, maintain a process for checking CASA publications and AD amendments for updated serial numbers, position numbers and timing. If position numbers in the Table are TBA, contact CASA or the OEM for guidance and document the advice.
Operational planning and spare parts. Anticipate lead times for OEM repair schemes and rotor/impeller replacements. Plan shop visits and spare parts procurement accordingly. Consider potential need to ground aircraft while awaiting AMO availability or parts; schedule work to conform with the AD's timing windows.
Insurance and contractual steps. Notify insurers and relevant contractual counterparties where necessary, especially where parts are scrapped and replacements will be charged under maintenance contracts or warranties.
Record retention. Retain logbook entries, AMO reports, quarantine/scrap evidence, CASA Defect Reporting Service notifications, and any special flight permit documentation for the durations required by applicable maintenance record rules. The AD itself requires these steps to be traceable in practice even though it does not state retention periods.
Escalation where ambiguity or TBA. If the AD tables present a TBA position number or ambiguous instruction, do not guess. Escalate to CASA and the OEM, obtain written direction, and document that correspondence as part of the compliance record.

Executing these steps will satisfy the AD’s stated machine of obligations. The AD requires documented proof of assessment in accordance with OEM specifications, quarantine/scrap of certain components, and reporting to CASA. Each of those is a discrete compliance requirement that should be attainable through proper AMO selection, documentation controls and procurement planning.

AD/AL 250/91 Amdt 2 Engine Compressor Module - Removal from Service

Plain English Summary

Deep Dive

What it does

Current sections

Rolls-Royce (Allison) Turbine Engines - 250 Series

Rolls-Royce (Allison) Turbine Engines - 250 Series

AD/AL 250/91 Amdt 2

AD/AL 250/91 Amdt 2

Engine Compressor Module - Removalfrom Service

Engine Compressor Module - Removal

10/2020

10/2020

Source text: opening excerpt

Rolls-Royce (Allison) Turbine Engines - Rolls-Royce (Allison) Turbine Engines - 250 Series

Rolls-Royce (Allison) Turbine Engines - 250 Series

Main concepts

Who it affects

Key duties and rights

Penalties and enforcement

How it interacts with other laws

Amendment history

Litigation history

Gotchas

How to comply