{"id":"F2006B09801","name":"AD/F28/67 Amdt 1 - MLG Main Fitting Subassembly","slug":"ad-f28-67-amdt-1-mlg-main-fitting-subassembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54722,"registerId":"commonwealth-F2006B09801-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F28/67 Amdt 1 - MLG Main Fitting Subassembly","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)  \nFokker F28 Series Aeroplanes\n\nAD/F28/67\n\nAmdt 1\n\n  \nMLG Main Fitting Subassembly 4/92\n\nApplicability: Model F28 series (except Mk 0100), equipped with Dowty Aerospace main undercarriage units with part/type numbers listed in the Requirement Document.\n\nRequirement: Action in accordance with Dowty Aerospace Mandatory Service Bulletin 32-161R Revision 2\n\nNote: RLD AD 91-080 refers.\n\nCompliance: Prior to 1 September 1992.\n\nNote: Revision 2 of the Requirement Document extends the applicability to additional undercarriage units.\n\nThe compliance of the previous issue of this Directive was \\- Prior to 31 December 1991.\n\nThis amendment is effective from 2 April 1992.\n\nBackground: Main fitting sub-assemblies have been found cracked through the side strut attachment lug to the main bore, causing loss of fluid. These failures were caused by damage to the anodic film and subsequent corrosion. The compliance time required by the Netherlands Authority was extended by one month.\n\nAmendment 1 is issued to reflect a revision of the manufacturer’s document.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope of addressing cracked main landing gear fittings. The changes are procedural: extending the compliance deadline and expanding the list of affected part numbers based on new manufacturer data. The core safety purpose — preventing landing gear failure due to corrosion — remains unchanged."},"complexity_factors":["Short, single-purpose directive (approximately 200 words)","Only 1 defined term implicitly referenced (the 'Requirement Document' containing part numbers)","Single cross-reference to Netherlands aviation authority (RLD AD 91-080) and one manufacturer service bulletin","Simple conditional logic: applicability limited to specific aircraft model and specific manufacturer part numbers","No nested exceptions or complex procedural requirements — essentially 'do what the manufacturer says by this date'","Amendment structure is straightforward: changes deadline and expands applicability list"],"plain_english_summary":"This CASA Airworthiness Directive requires inspections and repairs to the main landing gear main‑fitting subassembly on certain Fokker F28 aircraft due to cracking and hydraulic leaks caused by corrosion of the protective coating—risks that can lead to landing‑gear failure. It applies to operators with the specified Dowty gear.\n\nThe AD mandates compliance with Dowty Aerospace Mandatory Service Bulletin 32‑161R Revision 2, and this amendment extends the compliance deadline to 1 September 1992 while widening the list of affected gear part numbers."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment alters scope by adopting Revision 2 of the manufacturer’s Requirement Document, which 'extends the applicability to additional undercarriage units' (Note). It also updates the compliance deadline to 'Prior to 1 September 1992' replacing the previous requirement ('Prior to 31 December 1991') and records that the Netherlands Authority extended its compliance time (Compliance; Note; Background)."},"complexity_factors":["Mandatory reliance on a manufacturer service bulletin (Dowty Aerospace Mandatory Service Bulletin 32-161R Revision 2) for technical procedures and scope (Requirement).","Applicability limited to specific airframe model and listed Dowty part/type numbers, with an exclusion (except Mk 0100) (Applicability).","Amendment revises the Requirement Document (Revision 2) and extends applicability to additional undercarriage units (Note).","Fixed compliance deadline that replaces an earlier deadline (Compliance; previous compliance date stated).","Operators must identify affected parts from the Requirement Document, creating administrative burden to locate and verify listed part/type numbers.","Coordination/consistency with another authority (Netherlands Authority) and prior directive referenced (Background; Note: RLD AD 91-080)."],"plain_english_summary":"This directive requires operators of Fokker F28 aeroplanes (except Mk 0100) fitted with specified Dowty main undercarriage units to carry out the inspection/repair actions set out in Dowty Aerospace Mandatory Service Bulletin 32-161R Revision 2 to address corrosion-related cracking and fluid loss. Operators must comply before 1 September 1992. The regulator mandates the work and the manufacturer’s revised document expands the set of affected undercarriage units and updates the compliance timetable."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f28-67-amdt-1-mlg-main-fitting-subassembly","history":"/api/acts/ad-f28-67-amdt-1-mlg-main-fitting-subassembly/history","analysis":"/api/acts/ad-f28-67-amdt-1-mlg-main-fitting-subassembly/analysis","conflicts":"/api/acts/ad-f28-67-amdt-1-mlg-main-fitting-subassembly/conflicts","importantCases":"/api/acts/ad-f28-67-amdt-1-mlg-main-fitting-subassembly/important-cases","documents":"/api/acts/ad-f28-67-amdt-1-mlg-main-fitting-subassembly/documents"}}