{"id":"F2006B09786","name":"AD/F28/51 - Main Landing Gear Bay Cracking","slug":"ad-f28-51-main-landing-gear-bay-cracking","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54705,"registerId":"commonwealth-F2006B09786-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F28/51 - Main Landing Gear Bay Cracking","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)  Fokker F28 Series Aeroplanes\n\n \n\nAD/F28/51 Main Landing Gear Bay Cracking 2/86\n\nApplicability: All model F28 with S/Nos 11003 to 11091, 11094 to 11135, 11991 and 11992. Requirement:               Action in accordance with Fokker SB F28/57-76.\n\nNote: RLD AD 85-87 refers.\n\n \n\nCompliance: Prior to 31 March 1986.\n\n \n\nThe manufacturer reports an instance of a crack in the area of Station 2635 and the rear spar.\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":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive addressing a specific structural defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating inspection/repair of main landing gear bay cracking."},"complexity_factors":["Extremely short document (under 200 words)","Only one substantive requirement: comply with external technical document (Fokker SB F28/57-76)","No defined terms section — relies entirely on external references","Simple applicability test based on aircraft serial number ranges","Single compliance deadline with no conditional extensions or exceptions","No nested logic, cross-references to other legislation, or procedural steps beyond 'do what the manufacturer says'"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\nOrders owners and operators of specific Fokker F28 aircraft to inspect and repair a known safety problem — cracking in the main landing gear bay area (specifically around \"Station 2635\" and the rear spar, which are structural reference points on the aircraft).\n\n**Who it affects:**\nOwners and operators of Fokker F28 aircraft with serial numbers 11003 to 11091, 11094 to 11135, 11991 and 11992.\n\n**What they must do:**\nFollow the manufacturer's instructions in **Fokker Service Bulletin F28/57-76** (a technical repair notice from the plane maker). The directive references a Dutch aviation authority notice (RLD AD 85-87) for additional context.\n\n**When:**\nThe work had to be completed before 31 March 1986.\n\n**Why it matters:**\nCracks in the landing gear bay can compromise the aircraft's structural integrity — potentially leading to gear failure or loss of control. This directive forces operators to fix the problem before the aircraft can continue flying, preventing accidents."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument itself states applicability, the required action (referring to the manufacturer’s service bulletin), and a compliance date. It contains no language indicating an amendment to its own scope or a change from an earlier stated intent within the text provided. Therefore there is no evidence in this document that the scope has changed."},"complexity_factors":["Narrow applicability specified by a list of serial numbers (requires checking operator records).","Technical procedures and repair/inspection detail are delegated to an external document (Fokker SB F28/57-76), increasing reliance on that bulletin.","Short, fixed compliance deadline (prior to 31 March 1986) creates urgency for affected operators.","Issue is technical (main landing gear bay / rear spar cracking), so implementation requires structural inspection/repair expertise.","Cross-reference to another AD (RLD AD 85-87) introduces an additional external dependency."],"plain_english_summary":"This directive requires owners/operators of specific Fokker F28s (S/Ns 11003–11091, 11094–11135, 11991–11992) to carry out the actions in Fokker Service Bulletin F28/57-76 to address a reported crack near Station 2635 and the rear spar. Compliance is mandatory by 31 March 1986; the AD delegates inspection/repair detail to the manufacturer’s bulletin and does not state cost, enforcement, or payment arrangements."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f28-51-main-landing-gear-bay-cracking","history":"/api/acts/ad-f28-51-main-landing-gear-bay-cracking/history","analysis":"/api/acts/ad-f28-51-main-landing-gear-bay-cracking/analysis","conflicts":"/api/acts/ad-f28-51-main-landing-gear-bay-cracking/conflicts","importantCases":"/api/acts/ad-f28-51-main-landing-gear-bay-cracking/important-cases","documents":"/api/acts/ad-f28-51-main-landing-gear-bay-cracking/documents"}}