{"id":"F2006B10989","name":"AD/JT8D/35 Amdt 1 - Combustion Chamber Outer Case","slug":"ad-jt8d-35-amdt-1-combustion-chamber-outer-case","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56578,"registerId":"commonwealth-F2006B10989-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT8D/35 Amdt 1 - Combustion Chamber Outer Case","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/35\n\nAmdt 1\n\n  \nCombustion Chamber Outer Case 1/99\n\nApplicability: Pratt & Whitney JT8D-1, \\-1A, \\-1b, \\-7 ,-7A, \\-7B, \\-9, \\-11, \\-15, \\-15A, \\-17, \\-17A, \\-17R\n\nand \\-17AR turbofan engines, with combustion chamber outer case (CCOC) part numbers 490547, 5421555, 616315, 728829, 728829-001, 730413, 730413-001,\n\n730414, 730414-001, 767197, 767279, or 767279-001 installed.\n\nRequirement: For engines identified by serial number (S/N) in Table 1 of FAA AD 98-04-39, perform a one time borescope inspection of the CCOC rear flange in accordance with paragraph 2.A.(5) of Pratt and Whitney Alert Service Bulletin (ASB) No.A6202, Revision 1, dated 4 January, 1998.\n\nCompliance: Unless previously accomplished:\n\n    For engines installed on McDonnell Douglas DC-9 series aircraft, inspect within 1,000 cycles in service (CIS) since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD AD/JT8D/22 Amdt 4 (FAA AD 96-23- 14), or within 100 CIS after the effective date of this AD, whichever occurs later.\n\n    2. For engines installed on Boeing 737 series aircraft, inspect within 1,500 CIS since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD/JT8D/22 Amdt 4 (FAA AD 96-23-14), or within 100 CIS after the effective date of this AD, whichever occurs later.\n\n    3. For engines installed on Boeing 727 series aircraft, inspect within 2,500 CIS since the last ultrasonic inspection of the CCOC rear flange performed in accordance with AD/JT8D/22 Amdt 4 (FAA AD 96-23-14), or within 100 CIS after the effective date of this AD, whichever occurs later.\n\nThis Amendment becomes effective on 28 January 1999.\n\nBackground: The FAA has advised that certain serial number JD8D engines have been inspected using an out-of-calibration ultrasonic probe. The inspection in question is the subject of AD/JT8D/22 Amdt 4. The one time borescope inspection will ensure the integrity of the CCOC aft flange has not been compromised by the discrepant inspection.\n\nThis amendment corrects the reference to FAA AD 98-04-39.\n\nThe original issue of this Airworthiness Directive became effective on 8 October 1998.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"This amendment corrects the reference to FAA AD 98-04-39 but does not expand the set of affected engines or add recurring obligations. It retains the original one‑time borescope inspection requirement tied to the serial numbers and the aircraft-type‑specific compliance windows; it is therefore an administrative correction rather than a change of substantive scope."},"complexity_factors":["Cross-references to FAA AD 98-04-39 and Pratt & Whitney Alert Service Bulletin No. A6202 Revision 1 (requires reading external documents to implement).","Applicability tied to specific engine serial numbers listed in Table 1 of FAA AD 98-04-39 (serial-number-specific scope).","Multiple engine CCOC part numbers listed (requires parts verification during maintenance).","Different compliance windows by aircraft type (DC-9: 1,000 CIS; 737: 1,500 CIS; 727: 2,500 CIS, or 100 CIS after effective date) increases tracking complexity.","Technical inspection method (borescope) follows earlier ultrasonic inspections, so implementers must check inspection history and prior AD AD/JT8D/22 Amdt 4 records.","Administrative amendment solely corrects a reference, requiring confirmatory checks of referenced ADs and dates."],"plain_english_summary":"AD/JT8D/35 Amdt 1 mandates a one‑time borescope inspection of the combustion‑chamber outer case (CCOC) rear flange on specified Pratt & Whitney JT8D engines (listed part‑ and serial‑numbers). It was issued because certain engines had earlier ultrasonic inspections performed with an out‑of‑calibration probe.\n\nOperators of affected McDonnell Douglas DC‑9, Boeing 737 and Boeing 727 aircraft must complete the inspection within the cycle limits set for each airframe type; operators bear the inspection and compliance costs."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope of the directive. It is a minor technical correction that fixes a reference citation without expanding or altering the substantive requirements, applicability, or intent of the original October 1998 directive."},"complexity_factors":["Multiple applicability criteria: specific engine models, specific part numbers, and specific serial numbers listed in an external table (Table 1 of FAA AD 98-04-39)","Three-tiered compliance schedule based on aircraft type (DC-9, 737, 727) with different cycle limits","Conditional compliance timing: 'whichever occurs later' clauses creating alternative deadlines","Cross-references to previous directives (AD/JT8D/22 Amdt 4, FAA AD 96-23-14, FAA AD 98-04-39) and external documents (Pratt & Whitney Alert Service Bulletin A6202)","Technical aviation terminology requiring specialized knowledge (CIS = cycles in service, borescope inspection, CCOC, ASB)"],"plain_english_summary":"This safety directive mandates a one-time borescope inspection of the combustion chamber outer case on certain Pratt & Whitney JT8D engines installed on McDonnell Douglas DC-9, Boeing 737, and Boeing 727 aircraft because earlier checks used an out-of-calibration ultrasonic probe and may have missed cracks. Compliance deadlines vary by aircraft type (shorter for DC-9, longer for 727). The check prevents possible engine failure, fire, or catastrophic damage. Amendment 1 only corrects the FAA reference number."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt8d-35-amdt-1-combustion-chamber-outer-case","history":"/api/acts/ad-jt8d-35-amdt-1-combustion-chamber-outer-case/history","analysis":"/api/acts/ad-jt8d-35-amdt-1-combustion-chamber-outer-case/analysis","conflicts":"/api/acts/ad-jt8d-35-amdt-1-combustion-chamber-outer-case/conflicts","importantCases":"/api/acts/ad-jt8d-35-amdt-1-combustion-chamber-outer-case/important-cases","documents":"/api/acts/ad-jt8d-35-amdt-1-combustion-chamber-outer-case/documents"}}