{"id":"F2006B06390","name":"AD/PW4000/1 - Thrust Reverser Aft Cascade Support","slug":"ad-pw4000-1-thrust-reverser-aft-cascade-support","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47692,"registerId":"commonwealth-F2006B06390-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PW4000/1 - Thrust Reverser Aft Cascade Support","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nPratt and Whitney Turbine Engines \\- PW4000 Series\n\nAD/PW4000/1 Thrust Reverser Aft Cascade Support 2/97\n\nApplicability: PW4000 series engines installed on Airbus A300-600 and A310-300 series aircraft incorporating a thrust reverser per Supplemental Type Certificate No. SJ514NE.\n\nRequirement: Inspect the thrust reverser aft cascade support frame in accordance the technical requirements of Pratt and Whitney Service Bulletin No. PW4NAC 78-78, Revision 6 dated 6 March 1996, Part 1 - Interim inspection.\n\nIncorporation of aft cascade support frames, Part Nos. 221-0516-505 (LH) and 221- 0516-506 (RH), constitutes terminating action for this Directive. Refer to Pratt and Whitney Service Bulletin No. PW4NAC 78-78, Revision 6, dated 6 March 1996, Part 2 - Permanent Modification.\n\nNote 1: FAA AD 96 \\-13-08 also refers.\n\nNote 2: Inspection and modification to later issues of the referenced service bulletin satisfies the intent of this Directive.\n\nCompliance: Effective 30 January 1997; as detailed in the requirement document.\n\nBackground: There have been reports of thrust reverser aft cascade support failures which have resulted in liberation of thrust reverser hardware during reverse thrust operation.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical failure mode in a defined population of engines. It has not expanded beyond its original purpose of addressing thrust reverser aft cascade support failures."},"complexity_factors":["Single, specific technical requirement referencing an external document (Pratt & Whitney Service Bulletin)","Only 2 defined part numbers for terminating action","Limited applicability (specific engine series, specific aircraft models, specific Supplemental Type Certificate)","Simple conditional logic: inspect first, then optionally replace to terminate the requirement","Short length (approximately 200 words of substantive content)","Two notes providing alternative compliance paths (later revisions of service bulletin acceptable, FAA AD cross-reference)"],"plain_english_summary":"This CASA Airworthiness Directive orders operators of Airbus A300-600 and A310-300 aircraft with Pratt & Whitney PW4000 engines (specific thrust reverser configuration) to address failures of the aft cascade support frame in the thrust reverser.  \n\nIt requires inspection per Pratt & Whitney instructions and replacement with an improved support frame to eliminate the defect. Compliance prevents debris loss, engine damage, and landing hazards."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The Directive's scope aligns with its stated safety objective: it mandates inspection per the Pratt & Whitney service bulletin for PW4000 engines on the specified Airbus types under STC SJ514NE and offers a defined terminating action by fitting identified part numbers. It does not broaden coverage to other engines or airframes and allows later service‑bulletin revisions to satisfy compliance (Requirement; Incorporation; Note 2)."},"complexity_factors":["Narrow technical scope but safety‑critical: focuses on a single component (aft cascade support) with failure reports (Background).","Relies on an external service document for inspection procedure and modification details (Service Bulletin No. PW4NAC 78-78 Rev 6) (Requirement).","Terminates when specific replacement parts are installed (Part Nos. 221-0516-505/506) — creates a clear but binary compliance path (Incorporation of aft cascade support frames).","Applicability limited to engines installed under a specific Supplemental Type Certificate (STC SJ514NE) — adds precision to which operators are affected (Applicability).","Regulatory acceptance of later revisions of the service bulletin reduces friction but introduces potential variability in what is taken as compliant (Note 2).","Cross‑reference to a corresponding FAA AD provides overlapping regulatory context but may require operators to track multiple authorities (Note 1).","Compliance deadline (effective date) imposes operational scheduling and potential downtime/costs for inspections or modifications (Compliance)."],"plain_english_summary":"Requires operators of PW4000 engines on Airbus A300‑600 and A310‑300 aircraft fitted under STC SJ514NE to carry out interim inspections of the thrust reverser aft cascade support per Pratt & Whitney Service Bulletin PW4NAC 78‑78 Rev 6, and allows fitting specified replacement frames (PNs 221‑0516‑505/506) as terminating action. It responds to reported support failures that released reverser hardware; compliance is effective 30 January 1997. Inspection and modification costs and aircraft downtime fall to operators; the Civil Aviation Safety Authority enforces the directive."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pw4000-1-thrust-reverser-aft-cascade-support","history":"/api/acts/ad-pw4000-1-thrust-reverser-aft-cascade-support/history","analysis":"/api/acts/ad-pw4000-1-thrust-reverser-aft-cascade-support/analysis","conflicts":"/api/acts/ad-pw4000-1-thrust-reverser-aft-cascade-support/conflicts","importantCases":"/api/acts/ad-pw4000-1-thrust-reverser-aft-cascade-support/important-cases","documents":"/api/acts/ad-pw4000-1-thrust-reverser-aft-cascade-support/documents"}}