{"id":"F2006B09629","name":"AD/F100/28 - MLG Apex Joint and Shimmy Damper Attachment","slug":"ad-f100-28-mlg-apex-joint-and-shimmy-damper-attachment","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54413,"registerId":"commonwealth-F2006B09629-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F100/28 - MLG Apex Joint and Shimmy Damper Attachment","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 F100 (F28 Mk 100) Series Aeroplanes\n\nAD/F100/28 MLG Apex Joint and Shimmy Damper Attachment 4/99\n\nApplicability: F.28 Mk.0070 and Mk.0100 aircraft, all serial numbers, if equipped with Menasco Aerospace Main Landing Gear (MLG) Units (LH) Part Number (P/N) 41050-5, 41050-7 or P/N 41060-1; and (RH) P/N 41050-6, 41050-8 or P/N 41060-2.\n\nRequirement: Inspect the Main Landing Gear Apex Joint and Shimmy Damper in accordance with the Accomplishment Instructions of Fokker 70/100 Service Bulletin (SB) F100-32- 113 dated 28 May 1998.\n\nNote: RLD BLA 1998-058(A) refers.\n\nCompliance: Unless already accomplished before 3 June 1999. After 22 April 1999, no affected spare MLG units may be installed as a replacement part unless it has been inspected in accordance with the Requirement of this directive.\n\nThis Airworthiness Directive becomes effective on 22 April 1999.\n\nBackground: An operator reported a landing incident with a F.28 Mk.0070 where heavy vibration was felt during roll-out, coming from the main landing gear. The initial inspection, after the aircraft had been stopped on the runway, revealed the torque links of the RH MLG to be disconnected at the apex joint. Subsequent inspections of other aircraft revealed that in some cases, loss of torque was also found on the torque link centre joint apex bolt and shimmy damper attachment bolts. The compliance date for inspections of affected parts installed on aircraft has already passed.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect identified in a particular aircraft component. It has not expanded beyond its original purpose of mandating inspections for the identified landing gear defect."},"complexity_factors":["Single, specific technical requirement (inspect per referenced service bulletin)","Limited applicability (specific aircraft models and specific part numbers only)","No nested exceptions or conditional logic","Only 3 compliance conditions (already done, deadline for installed parts, deadline for spare parts)","No defined terms section (relies on external technical references)","Short document (approximately 200 words)"],"plain_english_summary":"This Airworthiness Directive orders mandatory inspections of the apex joint and shimmy-damper attachments on main landing gear of certain Fokker 70/100 (F28 Mk.0070/Mk.0100) aircraft equipped with specified Menasco MLG units after reports of loose bolts causing violent landing/taxi shimmy. If undetected, bolt failure could lead to gear collapse or loss of control.\n\nThe AD took effect 22 April 1999, banned installation of uninspected spare gears after that date, and required in-service inspections by 3 June 1999."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"Scope remains aligned with the corrective intent stated in the directive: inspect specified MLG apex joint and shimmy damper units on defined Fokker models and bar installation of uninspected spare units. The instrument targets those aircraft and parts identified after reports of torque-link and bolt loss; the source shows no expansion beyond that corrective purpose."},"complexity_factors":["Technical specificity: multiple Menasco MLG part numbers listed (LH and RH variants) increase identification burden.","Conditional applicability: applies only to aircraft \"if equipped with\" specified MLG units, requiring record checks.","External procedural dependence: inspection method delegated to Fokker Service Bulletin F100-32-113 (external document access required).","Staggered compliance timing: effective date (22 April 1999) and separate compliance allowance (unless done before 3 June 1999) create scheduling nuance.","Installation restriction: prohibition on fitting affected spare MLG units after 22 April 1999 adds supply-chain compliance and tracking obligations.","Safety-critical hardware: potential for immediate operational risk raises urgency and may demand rapid resource allocation.","Cross-references: note to RLD BLA 1998-058(A) requires consult of additional records for full context."],"plain_english_summary":"Requires mandatory inspection of the main landing gear apex joint and shimmy damper on Fokker F.28 Mk.0070 and Mk.0100 aircraft equipped with specified Menasco MLG part numbers, using Fokker Service Bulletin F100-32-113. Operators, maintenance organisations and spare-parts suppliers must inspect affected gear by the stated dates, and may not fit affected spare MLG units after 22 April 1999 unless inspected. The measure responds to reports of torque-link and attachment-bolt loss that produced heavy vibration on roll-out."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f100-28-mlg-apex-joint-and-shimmy-damper-attachment","history":"/api/acts/ad-f100-28-mlg-apex-joint-and-shimmy-damper-attachment/history","analysis":"/api/acts/ad-f100-28-mlg-apex-joint-and-shimmy-damper-attachment/analysis","conflicts":"/api/acts/ad-f100-28-mlg-apex-joint-and-shimmy-damper-attachment/conflicts","importantCases":"/api/acts/ad-f100-28-mlg-apex-joint-and-shimmy-damper-attachment/important-cases","documents":"/api/acts/ad-f100-28-mlg-apex-joint-and-shimmy-damper-attachment/documents"}}