{"id":"F2008L00879","name":"AD/PW300/1 Amdt 1 - Engine High Pressure Compressor Drum","slug":"ad-pw300-1-amdt-1-engine-high-pressure-compressor-drum","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":73001,"registerId":"commonwealth-F2008L00879-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Pratt and Whitney Canada Turbine Engines","sectionType":"division","heading":"Pratt and Whitney Canada Turbine Engines - PW300 Series","content":"### Pratt and Whitney Canada Turbine Engines - PW300 Series\n\n| AD/PW300/1 Amdt 1 | Engine High Pressure Compressor Drum | 4/2008 |\n| ----------------- | ------------------------------------ | ------ |\n\n| Applicability: | All post-Service Bulletin (SB) 24287, Pratt and Whitney Canada PW305A and PW305B Engines without SB PW300-72-24376 incorporated. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | On all PW305A and PW305B engines with post SB PW300-72-24462 HPC drum rotor assemblies P/Ns 30B2478 and 30B2542, accomplish the following:1.a. Gain access to inside of affected HPC rotor assembly and inspect (boroscope) its interior for cracks in accordance with the PW305 MM 05-20-00 \"Periodic Inspections, Boroscope\" requirements.1.b. If a crack is found, remove the engine for HPC drum rotor replacement.Inspection of affected HPC drum rotor assembly per SB PW300-72-24462 and/or PW305 MM 05-20-00 requirements prior to the effective date of this directive satisfy the actions detailed in Requirement 1 of this AD.2. Repeat the boroscope inspection per Requirement 1.a of this AD.2.b. If a crack is found, remove the engine for HPC rotor drum replacement.Replacement of the affected HPC rotor assembly P/N 30B2478 or 30B2542withPost-SB PW300-72-24376 assembly P/N 31B6325-01 or later superseding P/N, will constitute terminating action for the inspection requirements of this AD.Note: Transport Canada AD CF-2007-25R1 dated 13 February 2008 refers. |\n| Compliance: | 1.a. Remains unchanged as: Within 500 flight hours after 17 January 2008 (the effective date of the original issue of this AD).1.b. Before further flight.2.a. At intervals not to exceed 1350 flight cycles per PW305 MM 05-20-00.2.b. Before further flight. |\n| | This Amendment becomes effective on 10 April 2008. |\n\n| Background: | P&WC has determined that the Post-Service Bulletin (SB) PW300-72-24287 High Pressure Compressor (HPC) drum rotor assemblies P/N 30B2478 and 30B2542 on PW 305A and PW305B engines with single stage coated labyrinth seals are susceptible to developing significant cracks in the region of the labyrinth seal.P&WC issued SB PW300-72-24462 for initial inspection of affected HPC drum rotor assemblies for cracks. In addition, the PW305 Maintenance Manual (MM) 05-20-00 was revised (Revision No.26) accordingly, to add a requirement for repeat inspection intervals. A new P/N 31B6325-01, HPC drum rotor assembly, which is not susceptible to the subject cracking, is made available through SB PW300-72-24376, as a terminating action for the required repeat inspection.Recent data (Ref: Service Information Letter: PW300-093) indicates that a number of high-time Pre-SB-PW300-72-24376 HPC drum rotor assemblies (P/Ns 30B2478 and 30B2542), with potential for a hazardous disk failure in consequence of non-compliance with the inspection requirements, are still in-service. This AD is issued to mandate the inspection of the affected P/N 30B2478 and 30B2542 HPC drum rotor assemblies in accordance with PW305-MM-05-20-00 requirements.This amendment corrects a typographical error in the P/N of HPC drum assemblies listed in Requirement 2 of this AD.The original issue of this AD became effective on 17 January 2008. |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n\n![](image.001.png) \nDavid Punshon \nDelegate of the Civil Aviation Safety Authority\n\n26 February 2008","sortOrder":0},{"sectionNumber":"AD/PW300/1 Amdt 1","sectionType":"part","heading":"AD/PW300/1 Amdt 1","content":"## AD/PW300/1 Amdt 1","sortOrder":1},{"sectionNumber":"Engine High Pressure Compressor Drum","sectionType":"part","heading":"Engine High Pressure Compressor Drum","content":"## Engine High Pressure Compressor Drum","sortOrder":2},{"sectionNumber":"4/2008","sectionType":"part","heading":"4/2008","content":"## 4/2008","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment is purely corrective — it fixes a typographical error in part numbers listed in Requirement 2. The scope remains identical to the original January 2008 directive: mandatory safety inspections for specific at-risk engine components. No expansion of regulated parties, activities, or compliance obligations occurred."},"complexity_factors":["Heavy use of alphanumeric part numbers and service bulletin references (SB PW300-72-24287, P/N 30B2478, etc.) that require cross-referencing external technical documents","Nested applicability conditions: applies to 'post-SB 24287' engines but 'without SB PW300-72-24376 incorporated' — creating a narrow window of affected equipment","Multiple compliance timelines with different triggers (flight hours vs. flight cycles, 'before further flight' immediate actions)","Technical terminology assumes aviation maintenance knowledge (boroscope inspection, labyrinth seals, HPC drum rotor assemblies)","Circular logic in compliance: Requirement 2 references Requirement 1.a, creating internal cross-referencing"],"plain_english_summary":"This CASA Airworthiness Directive mandates boroscopic inspections of the High Pressure Compressor (HPC) drum rotor on certain Pratt & Whitney Canada PW305A/B engines to detect cracks near the labyrinth seals. It targets operators with specific drum-rotor parts installed after SB 24287 but before SB PW300-72-24376. The inspections (and removal if cracked) prevent catastrophic engine failure; replacing the part with the improved design ends the inspections. This amendment corrects a typographical error in the January 2008 AD."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The amendment corrects a typographical error in the part number listed in Requirement 2 but does not change the substantive applicability, inspection requirements, compliance timings, or terminating action of the original AD (original effective 17 January 2008; amendment effective 10 April 2008)."},"complexity_factors":["Technical specificity: multiple precise part numbers (30B2478, 30B2542, 31B6325‑01) increase identification burden","Cross‑references to external documents (Service Bulletins PW300‑72‑24462, PW300‑72‑24376 and PW305 MM 05‑20‑00) require operators to consult other sources","Inspection method specified (boroscope) and decision rule (remove engine if crack found) impose operational procedures and possible engine removal","Multiple compliance thresholds and timings (initial 500 flight hours; repeat ≤1,350 flight cycles; 'before further flight' if crack found) increase scheduling complexity","Terminating action (part replacement) shifts costs from repeated inspections to discrete capital replacement for some operators","Applicability conditional on prior incorporation of specified SBs (engines without SB PW300‑72‑24376) requires record checks","Amendment scope limited to correcting a typographical error in a P/N, which creates a need to reconcile versions of the AD and SBs"],"plain_english_summary":"This directive forces operators of certain Pratt & Whitney PW305A/B engines to boroscope-inspect specified high‑pressure compressor (HPC) drum rotor assemblies for cracks and to remove and replace the engine if any crack is found. Replacing the affected drum with the post‑service‑bulletin assembly (P/N 31B6325‑01) ends the inspection requirement.\n\nThe AD sets initial and repeat inspection deadlines (initial within 500 flight hours; repeats not to exceed 1,350 flight cycles), creating direct maintenance costs and downtime for operators. The amendment corrects a typographical part‑number error and does not alter required actions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pw300-1-amdt-1-engine-high-pressure-compressor-drum","history":"/api/acts/ad-pw300-1-amdt-1-engine-high-pressure-compressor-drum/history","analysis":"/api/acts/ad-pw300-1-amdt-1-engine-high-pressure-compressor-drum/analysis","conflicts":"/api/acts/ad-pw300-1-amdt-1-engine-high-pressure-compressor-drum/conflicts","importantCases":"/api/acts/ad-pw300-1-amdt-1-engine-high-pressure-compressor-drum/important-cases","documents":"/api/acts/ad-pw300-1-amdt-1-engine-high-pressure-compressor-drum/documents"}}