{"id":"F2006B10981","name":"AD/JT8D/20 Amdt 2 - Combustion Chamber Cans","slug":"ad-jt8d-20-amdt-2-combustion-chamber-cans","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56565,"registerId":"commonwealth-F2006B10981-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT8D/20 Amdt 2 - Combustion Chamber Cans","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 \\- JT8D Series\n\nAD/JT8D/20\n\nAmdt 2\n\n  \nCombustion Chamber Cans 5/96\n\nApplicability: All JT8D models fitted with combustion chamber cans other than P/N 5001958-02/- 022 or 5001959-02/-022.\n\nRequirement: Inspect the combustion chamber liners for cracking in accordance with Pratt and Whitney (P&W) Service Bulletin (SB) 5639, Revision 10 or as otherwise approved by the Authority.\n\nNote: FAA AD 86-09-02 Revision 2 refers.\n\nCompliance: Effective: 25 April 1996:\n\nUnless otherwise accomplished, as detailed in the requirement document.\n\nBackground: This Directive has been raised to repetitively inspect JT8D combustion chamber liners which have accumulated specific time since new, since repair or since last inspection in order to monitor their in-service condition.\n\nThis amendment references the use of the latest P&W SB and advises the latest revision of the applicable FAA Directive.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment (Amdt 2) maintains the original scope of AD/JT8D/20. It updates the referenced technical document to the latest Pratt & Whitney Service Bulletin revision and notes the corresponding FAA directive revision. The core purpose — repetitive inspection of combustion chamber liners for cracking — remains unchanged from the original 1996 directive."},"complexity_factors":["Single, clearly defined applicability criterion (engine model + part number exclusion)","One primary technical requirement referencing an external document (P&W Service Bulletin)","Simple compliance structure: effective date plus 'unless otherwise accomplished' standard language","No nested exceptions or conditional logic beyond the initial part number exclusion","Background section provides clear rationale without adding legal conditions","Cross-reference to FAA AD 86-09-02 Revision 2 is informational only, not a separate compliance obligation"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific maintenance actions on aircraft engines.\n\n**What it does:** This directive orders repetitive inspections of **combustion chamber cans** (the metal containers where fuel burns inside jet engines) on **Pratt & Whitney JT8D series engines**. These engines power older Boeing 737-100/200 aircraft and some military planes.\n\n**Who must comply:** Anyone operating aircraft with JT8D engines **except** those already fitted with specific improved part numbers (P/N 5001958-02/-022 or 5001959-02/-022). If your engine has the old-style combustion chamber cans, this applies to you.\n\n**What must be done:** Operators must inspect the combustion chamber liners (the inner walls of the combustion chamber) for cracks following Pratt & Whitney Service Bulletin 5639, Revision 10 — or use an alternative method pre-approved by CASA.\n\n**Why it matters:** Cracked combustion chamber liners can lead to engine failure, fire, or catastrophic damage. The directive requires **repetitive inspections** based on accumulated flight hours since the part was new, repaired, or last inspected. This catches fatigue cracks before they become dangerous.\n\n**Key timing:** The directive became effective on **25 April 1996** and remains ongoing (repetitive inspections required throughout the engine's life)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment does not change the core scope of the directive (it continues to require repetitive inspections of JT8D combustion chamber liners and to exclude the two listed P/Ns). The principal change described in the text is procedural: the amendment updates the directive to reference the latest Pratt & Whitney service bulletin and the latest revision of the applicable FAA AD, and it specifies the effective date (Background, Requirement, Compliance). The substantive obligation—inspect liners for cracking—remains the same."},"complexity_factors":["Dependence on external technical document (P&W SB 5639 Rev 10) for inspection intervals and procedures (Requirement).","Reference and linkage to another regulator’s directive (FAA AD 86-09-02 Revision 2) without reproducing its text (Note).","Applicability carve-outs by part number create a limited exclusion set (Applicability).","Allowance for alternative procedures subject to Authority approval introduces administrative discretion (Requirement).","Technical nature of inspections (crack detection) requires specialised maintenance capability, though the AD itself is short and prescriptive about the obligation (Requirement, Background)."],"plain_english_summary":"This AD mandates repetitive inspections of Pratt & Whitney JT8D combustion chamber liners for cracking, to be carried out per P&W Service Bulletin 5639 Revision 10 or an Authority‑approved alternative, and cross‑references the related FAA AD. It applies to all JT8D cans except P/Ns 5001958-02/-022 and 5001959-02/-022, is effective 25 April 1996, and places inspection and repair costs and compliance responsibility on operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt8d-20-amdt-2-combustion-chamber-cans","history":"/api/acts/ad-jt8d-20-amdt-2-combustion-chamber-cans/history","analysis":"/api/acts/ad-jt8d-20-amdt-2-combustion-chamber-cans/analysis","conflicts":"/api/acts/ad-jt8d-20-amdt-2-combustion-chamber-cans/conflicts","importantCases":"/api/acts/ad-jt8d-20-amdt-2-combustion-chamber-cans/important-cases","documents":"/api/acts/ad-jt8d-20-amdt-2-combustion-chamber-cans/documents"}}