{"id":"F2006B09007","name":"AD/DHC-1/27 - Seat Restraint Installations - Modification","slug":"ad-dhc-1-27-seat-restraint-installations-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52662,"registerId":"commonwealth-F2006B09007-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-1/27 - Seat Restraint Installations - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  De Havilland DHC-1 (Chipmunk) Series Aeroplanes\n\n \n\nAD/DHC-1/27 Seat Restraint Installations - Modification 10/76\n\nApplicability: All models.\n\n \n\nRequirement: Modify each seat restraint installation by fitting a safety harness in accordance with a scheme approved by the Secretary.\n\n \n\nNote: Guidelines for installation schemes are outlined in Airworthiness Advisory Circular No. 62 dated March 1972.\n\n \n\nCompliance: Unless already accomplished, before 1 October 1976.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1546},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The instrument remains precisely focused on its original purpose: mandating safety harness retrofits for Chipmunk aircraft. No expansion of scope beyond seat restraints is evident."},"complexity_factors":["Single, straightforward mechanical requirement with no exceptions","Only one external reference (Airworthiness Advisory Circular No. 62)","No defined terms or conditional logic","Clear, absolute compliance deadline"],"plain_english_summary":"**What this does:** This directive mandates a safety upgrade for all De Havilland DHC-1 Chipmunk aircraft. Owners and operators must install proper safety harnesses (seat belts) in each seat.\n\n**Who it affects:** Anyone operating or maintaining De Havilland DHC-1 (Chipmunk) series aeroplanes.\n\n**What must be done:**\n- Install a safety harness for each seat restraint installation\n- The installation must follow a specific plan (scheme) approved by the Secretary (the senior government official responsible for aviation)\n- Guidance on how to create these installation plans can be found in Airworthiness Advisory Circular No. 62 from March 1972\n\n**Deadline:** The modification had to be completed before 1 October 1976, unless the aircraft already had compliant harnesses fitted."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-1-27-seat-restraint-installations-modification","history":"/api/acts/ad-dhc-1-27-seat-restraint-installations-modification/history","analysis":"/api/acts/ad-dhc-1-27-seat-restraint-installations-modification/analysis","conflicts":"/api/acts/ad-dhc-1-27-seat-restraint-installations-modification/conflicts","importantCases":"/api/acts/ad-dhc-1-27-seat-restraint-installations-modification/important-cases","documents":"/api/acts/ad-dhc-1-27-seat-restraint-installations-modification/documents"}}