{"id":"F2009L03366","name":"AD/F27/160 - MLG Sliding Member End-Stop","slug":"ad-f27-160-mlg-sliding-member-end-stop","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":140941,"registerId":"commonwealth-F2009L03366-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Fokker F27 Series Aeroplanes","sectionType":"division","heading":"Fokker F27 Series Aeroplanes","content":"### Fokker F27 Series Aeroplanes\n\n| AD/F27/160 | MLG Sliding Member End-Stop | 10/2009 |\n| ---------- | --------------------------- | ------- |\n\n| Applicability: | Model F27 Mark 500 and 600 aircraft, serial numbers 10452, 10525, 10530, 10531, 10550, 10557, 10559, 10566, 10569, 10589, 10603, 10605, 10606, 10613, 10615, 10623 through 10631, 10633, 10637, 10639, 10641, 10642, 10669 and 10672.Note 1: The listed serial numbers are the only aircraft that have Rough Field Version (RFV) MLG installed.                                                                                                                              |\n| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the requirements of EASA AD 2009-0145.Note 2: Fokker Services SBF27/32-172 dated 26 January 2009, or later EASA approved revision, refers.                                                                                                                                                                                                                                                                                                         |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of24 September 2009.                                                                                                                                                                                                                                                                                                                                                                                 |\n|                | This Airworthiness Directive becomes effective on 24 September 2009.                                                                                                                                                                                                                                                                                                                                                                                                         |\n| Background:    | A Fokker 50 operator reported an over-extended main landing gear sliding member after landing. Investigation revealed that an end stop had unscrewed, and that no lockwire was present on the two lockbolts which hold the end stop. Earlier F27 Mark 500 and 600 “RFV” aircraft are equipped with similar design MLG units. This condition, if not corrected, could lead to structural damage of the main gear and loss of control of the aircraft during the landing roll. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n12 August 2009","sortOrder":0},{"sectionNumber":"AD/F27/160","sectionType":"part","heading":"AD/F27/160","content":"## AD/F27/160","sortOrder":1},{"sectionNumber":"MLG Sliding Member End-Stop","sectionType":"part","heading":"MLG Sliding Member End-Stop","content":"## MLG Sliding Member End-Stop","sortOrder":2},{"sectionNumber":"10/2009","sectionType":"part","heading":"10/2009","content":"## 10/2009","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The instrument revises the effective date to 24 September 2009 while leaving the applicability (specific F27 Mark 500/600 serial numbers with RFV MLG) and the substantive requirement to follow EASA AD 2009-0145 (and referenced Fokker SBF27/32-172) unchanged. The change is temporal rather than substantive (Compliance; Applicability; Requirement)."},"complexity_factors":["Narrow applicability to a defined list of serial numbers and only those with Rough Field Version (RFV) MLG installed — limits affected parties but requires accurate fleet identification (Applicability).","Dependence on an external EASA AD (2009-0145) and a Fokker service bulletin (SBF27/32-172) for the specific actions — creates a cross-reference dependency for compliance (Requirement).","Safety-critical technical work on main landing gear (inspection, securing end-stop, lockwire) — requires skilled maintenance and possible parts/workshop downtime (Background; Requirement).","Compliance timing revised (effective date set to 24 September 2009) — scheduling and retrospective compliance considerations for operators (Compliance).","Financial and operational burden falls on aircraft owners/operators of the listed serial numbers to perform inspections/repairs and to source any required parts or maintenance slots (Applicability; Requirement).","Low regulatory discretion in substance — directive mandates action 'in accordance with' the referenced documents, though later EASA-approved revisions of the service bulletin may be followed (Requirement, Note 2).","Enforcement and formal effect established by CASA delegate signature and effective date — administrative certainty but limited to the stated serial-number cohort (Delegate signature; Compliance)."],"plain_english_summary":"Requires operators of specific Fokker F27 Mark 500 and 600 aeroplanes (the listed serial numbers fitted with Rough Field Version main landing gear) to carry out the inspection and corrective actions set out in EASA AD 2009-0145, as referenced in Fokker Services SBF27/32-172. The AD responds to an incident where an MLG end-stop unscrewed and lockbolts lacked lockwire; if not fixed this could cause structural damage to the main gear and loss of control during the landing roll."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard single-issue Airworthiness Directive addressing a specific mechanical defect in a limited fleet of aircraft. The scope remains tightly focused on the original safety concern without expansion into broader operational or regulatory matters."},"complexity_factors":["Very short document (under 300 words)","Only 1 defined term implicitly used (RFV = Rough Field Version)","No nested conditional logic or cross-references to other Australian legislation","Single straightforward requirement: comply with an external European directive","Clear applicability table with explicit serial number list","No exceptions or exemptions stated"],"plain_english_summary":"This AD mandates inspection and corrective work on the main landing gear of certain Fokker F27 Mark 500/600 aircraft with \"Rough Field Version\" gear because an end‑stop can unscrew if two lockbolts lack lockwire, allowing over‑extension and possible collapse on landing. It applies to 27 specific serial‑numbered aircraft and requires compliance with EASA AD 2009‑0145 and Fokker SBF27/32‑172 by 24 September 2009. This fixes a critical collapse risk."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f27-160-mlg-sliding-member-end-stop","history":"/api/acts/ad-f27-160-mlg-sliding-member-end-stop/history","analysis":"/api/acts/ad-f27-160-mlg-sliding-member-end-stop/analysis","conflicts":"/api/acts/ad-f27-160-mlg-sliding-member-end-stop/conflicts","importantCases":"/api/acts/ad-f27-160-mlg-sliding-member-end-stop/important-cases","documents":"/api/acts/ad-f27-160-mlg-sliding-member-end-stop/documents"}}