{"id":"F2005L03545","name":"AD/B737/10 Amdt 2 - Aft Lower Cargo Doorway Frame","slug":"ad-b737-10-amdt-2-aft-lower-cargo-doorway-frame","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":39056,"registerId":"commonwealth-F2005L03545-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 737 Series Aeroplanes","sectionType":"division","heading":"Boeing 737 Series Aeroplanes","content":"### Boeing 737 Series Aeroplanes\n\n| AD/B737/10 Amdt 2 | Aft Lower Cargo Doorway Frame | 13/2005 |\n| ----------------- | ----------------------------- | ------- |\n\n| Applicability: | Model 737-200 and -300 series aircraft, line numbers 6 through 1204.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 93-14-10Amdt 39-8634.Note: Boeing Service Bulletin 737-53-1096 original issue, or later FAA approved revision, refers.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of 22 December 2005.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |\n|                | This Amendment becomes effective on 22 December 2005.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |\n| Background:    | Frame cracking is attributed to fatigue from pressurisation loads. Frame cracks may result in severing of the frames and cracking of the adjacent fuselage skin. This would seriously reduce the strength of the fuselage in this area, and present a high risk of a rapid decompression.Amendment 1 made reference to the related FAA AD, and the fact that only frame modifications to the improved standard of Revision 1 to the related SB constitute terminating action.Amendment 2 is issued to update this Directive to the current FAA AD, which requires repetitive inspections to continue after installation of the optional terminating modification. This action was prompted by a structural reassessment of the Model 737 series aircraft. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n8 November 2005","sortOrder":0},{"sectionNumber":"AD/B737/10 Amdt 2","sectionType":"part","heading":"AD/B737/10 Amdt 2","content":"## AD/B737/10 Amdt 2","sortOrder":1},{"sectionNumber":"Aft Lower Cargo Doorway Frame","sectionType":"part","heading":"Aft Lower Cargo Doorway Frame","content":"## Aft Lower Cargo Doorway Frame","sortOrder":2},{"sectionNumber":"13/2005","sectionType":"part","heading":"13/2005","content":"## 13/2005","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This instrument maintains its original scope as a safety directive for specific Boeing 737 cargo door frame issues. While Amendment 2 tightens compliance requirements (removing the terminating action exemption), this represents a refinement within the original safety purpose rather than scope creep. The instrument has not expanded to cover unrelated aircraft systems or models."},"complexity_factors":["Short, single-purpose instrument (approximately 250 words)","Only 2 defined applicability criteria (model series and line numbers)","Single cross-reference to FAA AD 93-14-10 and Boeing Service Bulletin 737-53-1096","No nested conditional logic or exceptions within the instrument itself","Technical complexity is externalised — the actual inspection procedures reside in the referenced FAA document and Boeing Service Bulletin, not in this legislative text","Simple amendment structure tracking changes from Amendment 1 to Amendment 2"],"plain_english_summary":"Operators of certain Boeing 737-200 and 737-300 aircraft (line numbers 6–1204) must inspect and, if needed, repair the aft lower cargo door frame to prevent cracking from pressurisation cycles that could lead to structural failure and rapid decompression. The AD mandates compliance with FAA AD 93-14-10 using Boeing Service Bulletin 737-53-1096, and Amendment 2 removes the previous terminating-action exemption—modified frames now require ongoing repetitive inspections."},"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":3,"scope_assessment":{"changed":true,"description":"Amendment 2 changes the scope of operator obligations compared with the earlier amendment. Amendment 1 treated a specific frame modification (Revision 1 to the Boeing Service Bulletin) as terminating action that would end the need for further inspections. Amendment 2 updates the Directive to the current FAA AD and removes that practical relief: it requires repetitive inspections to continue even after the optional modification. That change increases ongoing compliance obligations and lifecycle maintenance costs for operators who installed or plan to install the modification, and shifts the balance from a one‑time corrective pathway to a continuing inspection regime."},"complexity_factors":["Short, single-issue Airworthiness Directive focused on one structural location","One external normative reference: FAA AD 93-14-10 (Amendment 39-8634)","Reference to Boeing Service Bulletin 737-53-1096 (original issue or later FAA‑approved revision)","Conditional logic: optional terminating modification exists but Directive requires continued repetitive inspections (overrides prior terminating-action expectation)","Narrow applicability: specific models and line numbers (737-200 and -300, line numbers 6–1204)","No extensive defined‑term section or nested exceptions within the Directive text"],"plain_english_summary":"**What this instrument does**\n\n- This is an Airworthiness Directive (a mandatory safety instruction) that applies to Boeing 737-200 and 737-300 aeroplanes with line numbers 6 through 1204. (Line numbers identify individual airframes.)\n- It requires operators to carry out the inspection and corrective actions set out in the referenced FAA Airworthiness Directive (FAA AD 93-14-10, Amendment 39-8634) and refers to Boeing Service Bulletin 737-53-1096 (original issue or a later FAA‑approved revision).\n- The Directive’s effective date is 22 December 2005.\n\n**Why the rule exists (official rationale)**\n\n- Boeing and the regulator found cracking in the aft lower cargo doorway frame caused by fatigue from cabin pressurisation cycles. The cracks can grow, sever frames and damage the nearby fuselage skin. That damage can materially weaken the fuselage and create a high risk of rapid decompression.\n\n**What changed in this amendment (mechanical effect)**\n\n- Earlier advice (Amendment 1) said that installing a particular frame modification to the improved standard (Revision 1 of the Boeing Service Bulletin) would be a terminating action — i.e. it would end the need for further inspections. Amendment 2 updates the Directive to match the current FAA AD and requires operators to continue repetitive inspections even after installing the optional modification. In short: the optional modification does not relieve an operator from future inspections under the current FAA AD.\n\n**Who is affected and who pays**\n\n- Aircraft operators and owners of the specified 737-200/300 airframes must comply. Maintenance organisations doing the inspections and corrective work will carry out the tasks and hold records. Operators pay the costs of inspections, repairs and any modification work, plus associated downtime and logistics.\n\n**How it works in practice**\n\n- Operators must follow the inspection intervals, inspection procedures and corrective-action requirements spelled out in the FAA AD and the referenced Boeing Service Bulletin (or later FAA‑approved revision).\n- If cracks or damage are found, repairs or modifications specified by the FAA AD/SB must be done.\n- Even if an operator installs the optional \"terminating\" modification described in the Service Bulletin, the directive (as amended) requires them to keep doing repetitive inspections according to the FAA AD.\n\n**Practical consequences, trade-offs and implementation risks**\n\n- Safety benefit: ongoing inspections are aimed at detecting fatigue cracks before they threaten structural integrity (Background). That benefit is concentrated on passengers and crew who fly in affected airframes and on the operator’s risk exposure.\n- Cost and operational impact: owners/operators bear the direct costs of inspections, any repairs, and any modification work, plus aircraft downtime while work is done. Requiring inspections to continue after a modification raises the long‑run maintenance cost and schedule burden compared with a regime where the modification terminated further inspections.\n- Supply and scheduling risks: implementation depends on availability of approved parts, maintenance capacity and access to technical records. Delays in parts or maintenance slots can increase aircraft out-of-service time.\n- Compliance certainty: the Directive delegates technical detail to the FAA AD and the Boeing Service Bulletin; operators must ensure they use the current FAA‑approved revision. That reliance on external documents concentrates technical discretion in the FAA/Boeing documents and means Australian compliance depends on keeping in step with FAA updates.\n\n(References: Requirement and Background sections of the Directive.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-10-amdt-2-aft-lower-cargo-doorway-frame","history":"/api/acts/ad-b737-10-amdt-2-aft-lower-cargo-doorway-frame/history","analysis":"/api/acts/ad-b737-10-amdt-2-aft-lower-cargo-doorway-frame/analysis","conflicts":"/api/acts/ad-b737-10-amdt-2-aft-lower-cargo-doorway-frame/conflicts","importantCases":"/api/acts/ad-b737-10-amdt-2-aft-lower-cargo-doorway-frame/important-cases","documents":"/api/acts/ad-b737-10-amdt-2-aft-lower-cargo-doorway-frame/documents"}}