{"id":"F2006B02798","name":"AD/B727/94 Amdt 1 - Forward Cargo Compartment Sidewall Frame","slug":"ad-b727-94-amdt-1-forward-cargo-compartment-sidewall-frame","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42140,"registerId":"commonwealth-F2006B02798-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/94 Amdt 1 - Forward Cargo Compartment Sidewall Frame","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nBoeing 727 Series Aeroplanes\n\nAD/B727/94\n\nAmdt 1\n\n  \nForward Cargo Compartment Sidewall Frame 1/93\n\nApplicability: All models B727-100 and \\-100C series aircraft with line numbers 1 to 478 and 480.\n\nRequirement: Visually inspect internally the forward cargo compartment sidewall frames from BS 480 to BS 680 for cracks in accordance with Boeing SB 727-53-0068 Revision 4.\n\nNote: FAA AD 90-20-14 refers.\n\nCompliance: Inspect before 15600 flights, or within 2000 flights after 7 January 1993, or within 9000 flights since the last internal inspection in accordance with the original issue of this AD, or within 4000 flights since the last external inspection in accordance with the original issue of this AD, whichever occurs last.\n\nRe-inspect at intervals not exceeding 9000 flights until modified in accordance with Boeing SB 727-53-0068.\n\nBackground: Cracking of the forward cargo compartment frames was detected during fatigue testing and a number of operators have experienced cracks in those frames.\n\nAmendment 1 eliminates the previous option of the external inspection procedure. This procedure has been reassessed as inadequate to prevent a hazardous depressurisation.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment maintains the original safety purpose — preventing catastrophic failure of cargo compartment frames. It narrows rather than expands scope by removing the external inspection option, making the directive more stringent but not broader in application."},"complexity_factors":["Multiple alternative compliance deadlines ('whichever occurs last' calculation with 4 different flight count triggers)","Cross-reference to external Boeing Service Bulletin (SB 727-53-0068 Revision 4) and FAA AD 90-20-14","Technical aviation terminology requiring domain knowledge (BS 480/680 body stations, line numbers, flight cycles)","Amendment structure modifying previous requirements rather than standalone text"],"plain_english_summary":"This directive forces internal inspections of the forward cargo-compartment frames on early Boeing 727-100/-100C aircraft (roughly the first 479 airframes) operating in Australia, banning the previously allowed external-only checks. It sets firm deadlines and requires repeat inspections every 9,000 flights until Boeing’s permanent modification is installed.\n\nWhy it matters: undetected cracks in those frames can cause hazardous cabin depressurisation, so the amendment closes a safety gap left by unreliable external inspections."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment 1 narrows the compliance methods by eliminating the external inspection option and mandates internal inspections per Boeing SB 727-53-0068 Revision 4 (see 'Requirement' and 'Amendment 1'). This increases required inspection intrusiveness and ongoing re‑inspection obligations until modification, thereby expanding operational compliance burden while reducing an earlier, less invasive compliance route."},"complexity_factors":["Technical reference to Boeing Service Bulletin (SB 727-53-0068 Rev 4) — requires access to and interpretation of a manufacturer document","Multiple conditional compliance timings (before 15600 flights, within 2000 flights after a date, or within 9000/4000 flights since prior inspections — 'whichever occurs last')","Applicability limited to specific airframe line numbers (1–478 and 480), requiring record checks","Removal of the external-inspection option narrows compliance methods and may increase internal-access work-scopes","Mandatory re‑inspection interval (not exceeding 9000 flights) until modification — creates ongoing scheduling and tracking obligations","Detection of cracks may trigger repairs or modification, adding variable cost and downtime","Safety rationale tied to fatigue testing and operator reports, requiring operators to reconcile testing findings with fleet condition"],"plain_english_summary":"This Airworthiness Directive requires operators of specified Boeing 727‑100 and -100C aircraft (line numbers 1–478 and 480) to perform internal visual inspections of forward cargo compartment sidewall frames (BS480–BS680) for cracks, following Boeing Service Bulletin 727‑53‑0068 Revision 4, and to re‑inspect at prescribed intervals until the modification is done. It removes the previously permitted external inspection option. Operators pay for inspections and any repairs; the change is justified by detected fatigue cracking and to reduce the risk of hazardous depressurisation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-94-amdt-1-forward-cargo-compartment-sidewall-frame","history":"/api/acts/ad-b727-94-amdt-1-forward-cargo-compartment-sidewall-frame/history","analysis":"/api/acts/ad-b727-94-amdt-1-forward-cargo-compartment-sidewall-frame/analysis","conflicts":"/api/acts/ad-b727-94-amdt-1-forward-cargo-compartment-sidewall-frame/conflicts","importantCases":"/api/acts/ad-b727-94-amdt-1-forward-cargo-compartment-sidewall-frame/important-cases","documents":"/api/acts/ad-b727-94-amdt-1-forward-cargo-compartment-sidewall-frame/documents"}}