{"id":"F2006B02997","name":"AD/B737/97 - Fwd Galley Service Door Lower Gate Hinge","slug":"ad-b737-97-fwd-galley-service-door-lower-gate-hinge","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42356,"registerId":"commonwealth-F2006B02997-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B737/97 - Fwd Galley Service Door Lower Gate Hinge","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 737 Series Aeroplanes\n\nAD/B737/97 Fwd Galley Service Door Lower Gate Hinge 9/96\n\nApplicability: Model 737 series aircraft, as listed in Boeing Service Bulletin 737-52A1124; on which the actions specified in Boeing Service Bulletin 737-52-1097, Revision 1, or Revision 2, have not been accomplished.\n\nRequirement: Perform a detailed visual inspection to detect cracks of the lower gate hinge of the forward galley service door, in accordance with Boeing Alert Service Bulletin 737- 52A1124.\n\nNote 1: Replacement of the lower gate hinge of the lower galley service door with an improved hinge, in accordance with Boeing Alert Service Bulletin 737-52A1124, constitutes terminating action for the requirements of this Directive.\n\nNote 2: FAA AD 96-10-06 Amdt 39-9611 refers.\n\nCompliance: Within 400 flight cycles after 15 August 1996, and thereafter at intervals not to exceed 4500 flight cycles; until replacement with an improved hinge.\n\nBackground: The FAA received reports of fatigue cracks in the lower gate hinge on the forward galley service door. If the hinge fails, the hinge and its associated parts and the emergency escape slide could separate from the aircraft and be ingested into the engine, or could strike and damage the flight control surfaces.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, technical safety directive focused on a specific mechanical defect in a specific aircraft series. It has not expanded beyond its original purpose of addressing the identified fatigue crack risk in the forward galley service door hinge."},"complexity_factors":["Single, specific mechanical component targeted (one hinge on one door type)","Only one substantive requirement: visual inspection per manufacturer bulletin","Two straightforward compliance pathways: recurring inspections OR one-time replacement","Minimal cross-referencing (only to specific Boeing Service Bulletins and one FAA AD)","No defined terms section, no conditional logic, no nested exceptions","Total length: approximately 200 words"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspections of the lower hinge on the forward galley service door of affected Boeing 737s in Australia unless the hinge has been replaced per Boeing Service Bulletin 737-52-1097 (Rev 1 or 2). It targets operators of those aircraft to ensure the hinge is free of fatigue cracking.\n\nIt matters because cracked hinges can lead to door and escape-slide separation, risking engine ingestion or damage to wings/tail controls — a potential catalyst for catastrophic accidents — so the AD enforces preventive action."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD's scope aligns with its stated safety objective: it targets specific Boeing 737s listed in the referenced service bulletin and mandates inspections and optional replacement to mitigate hinge fatigue cracks. It does not broaden applicability beyond the aircraft identified or add unrelated obligations; it cross-references FAA AD guidance for coordination (Applicability; Requirement; Compliance; Note 2)."},"complexity_factors":["Targeted applicability — limited to aircraft listed in Boeing Service Bulletin 737-52A1124 (Applicability).","Clear, single technical action — detailed visual inspection for cracks (Requirement).","Recurring compliance timing with a defined terminating action — initial and repetitive flight‑cycle intervals, replacement ends inspections (Compliance; Note 1).","Reference to manufacturer service bulletins and FAA AD — dependence on external documents for scope and procedures (Applicability; Note 2).","Operational cost and logistics concentrated on aircraft operators — inspections and part replacement are operator expenses (Requirement; Compliance).","Safety-driven consequence specification — background links hinge failure to engine ingestion or control-surface damage, motivating mandatory action (Background)."],"plain_english_summary":"This Airworthiness Directive requires operators of specified Boeing 737 aircraft to carry out detailed visual inspections for cracks in the forward galley service door lower gate hinge and, if desired, replace the hinge with an improved part to stop the inspection cycle. It applies to aircraft listed in Boeing Service Bulletin 737-52A1124 and matters because a hinge failure could allow parts to separate and be ingested by an engine or strike flight controls, so operators pay for inspections and replacements."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-97-fwd-galley-service-door-lower-gate-hinge","history":"/api/acts/ad-b737-97-fwd-galley-service-door-lower-gate-hinge/history","analysis":"/api/acts/ad-b737-97-fwd-galley-service-door-lower-gate-hinge/analysis","conflicts":"/api/acts/ad-b737-97-fwd-galley-service-door-lower-gate-hinge/conflicts","importantCases":"/api/acts/ad-b737-97-fwd-galley-service-door-lower-gate-hinge/important-cases","documents":"/api/acts/ad-b737-97-fwd-galley-service-door-lower-gate-hinge/documents"}}