{"id":"F2006B06799","name":"AD/SC7/25 - Brake Unit Friction Pads","slug":"ad-sc7-25-brake-unit-friction-pads","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114656,"registerId":"commonwealth-F2006B06799-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SC7/25 - Brake Unit Friction Pads","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)  Short SC7 (Skyvan) Series Aeroplanes\n\n \n\nAD/SC7/25 Brake Unit Friction Pads 2/96\n\nApplicability: All Shorts Skyvan and Shorts Skyliner aircraft, with Dunlop Brake Unit Part No.\n\nAHA2133 or AH52109 installed.\n\n \n\nRequirement: Action in accordance with Dunlop Limited Mandatory Service Bulletin 32-1108.\n\n \n\nNote: Shorts Service Bulletin 32-71 refers.\n\n \n\nCompliance: Unless already accomplished, before 31 December 1995; thereafter as specified in the Requirement Document.\n\n \n\nBackground: A new friction pad material has been introduced because of the unavailability of the previously used material. Dynamometer tests have now shown that the permitted friction pad wear must be reduced to make sure that the brake can achieve a maximum high energy or rejected take-off stop.\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":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific technical issue with specific brake units on specific aircraft. It has not expanded beyond its original purpose of ensuring brake safety following a material change."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 defined part numbers for applicability","Single requirement referencing an external document (Dunlop Service Bulletin 32-1108)","No nested conditions or exceptions","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Straightforward compliance deadline structure"],"plain_english_summary":"This CASA Airworthiness Directive applies to Shorts Skyvan and Skyliner aircraft fitted with Dunlop brake units P/N AHA2133 or AH52109, requiring compliance with Dunlop Service Bulletin 32‑1108 (and related Shorts guidance) to inspect and replace brake friction pads. \n\nIt was issued because the replacement pad material wears differently and can reach an unsafe wear limit sooner, risking inadequate braking (e.g., on rejected take‑offs); initial compliance was required by 31 Dec 1995 with ongoing actions per the bulletin."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive's scope matches its stated purpose: it applies only to the named aircraft fitted with the specified Dunlop brake units and requires the actions in Dunlop Mandatory Service Bulletin 32-1108 to reduce permitted pad wear to meet braking performance. It does not expand obligations beyond those targeted maintenance and inspection requirements."},"complexity_factors":["Narrow applicability to a small fleet and two specific Dunlop part numbers (AHA2133, AH52109).","Primary technical requirements are normatively referenced to an external Mandatory Service Bulletin (Dunlop SB 32-1108), moving detail out of the regulatory text.","Retroactive compliance deadline (before 31 December 1995) plus ongoing intervals as specified in the service bulletin increases administrative tracking.","Safety-critical performance metric (reduced permitted pad wear) requires measurement, recordkeeping and verifiable maintenance practices.","Regulation text is brief; implementation depends on technical tests and procedures in the service bulletin and possibly Shorts Service Bulletin 32-71."],"plain_english_summary":"Mandates that operators of Shorts Skyvan and Shorts Skyliner aeroplanes fitted with Dunlop brake units AHA2133 or AH52109 carry out the work set out in Dunlop Mandatory Service Bulletin 32-1108. Mechanically, it reduces the allowable friction-pad wear limit for those brake units so the brakes can meet required high-energy and rejected-takeoff stopping performance. Operators must comply by 31 December 1995 if not already done and thereafter follow the service bulletin's ongoing instructions; costs and maintenance effort fall to the aircraft owners/operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sc7-25-brake-unit-friction-pads","history":"/api/acts/ad-sc7-25-brake-unit-friction-pads/history","analysis":"/api/acts/ad-sc7-25-brake-unit-friction-pads/analysis","conflicts":"/api/acts/ad-sc7-25-brake-unit-friction-pads/conflicts","importantCases":"/api/acts/ad-sc7-25-brake-unit-friction-pads/important-cases","documents":"/api/acts/ad-sc7-25-brake-unit-friction-pads/documents"}}