{"id":"F2006B07057","name":"AD/SM-205/35 - Landing Gear Actuator Damper","slug":"ad-sm-205-35-landing-gear-actuator-damper","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48792,"registerId":"commonwealth-F2006B07057-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SM-205/35 - Landing Gear Actuator Damper","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)  \nSIAI Marchetti S205 and S208 Series Aeroplanes\n\nAD/SM-205/35 Landing Gear Actuator Damper 12/93\n\nApplicability: Model S.205-18R, \\-20R, \\-22R; S.208 and S.208A.\n\nRequirement: Action in accordance with SIAI Marchetti Service Bulletin 205B49 Revision B.\n\nNote: RAI AD 93-221 refers.\n\nCompliance: For aircraft that have accumulated less than 500 hours time in service: At the 500 hour inspection.\n\nFor aircraft that have accumulated more than 500 hours time in service:\n\nWithin 100 hours time in service after 11 November 1993, and thereafter at intervals not to exceed 100 hours time in service.\n\nBackground: The RAI has received reports of damage to the landing gear actuator rubber damper. Deformation of the rubber damper, in conjunction with a small mis-adjustment of the landing gear system, could result in an unsafe down-lock condition.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive addressing a specific mechanical defect in specific aircraft models. It has not expanded beyond its original safety purpose."},"complexity_factors":["Single, specific mechanical component addressed","Only two compliance pathways based on flight hours (under 500 vs over 500)","No defined terms section or interpretation provisions","Minimal cross-referencing (only one service bulletin and one related directive mentioned)","Short, single-issue scope with clear applicability criteria","No conditional logic beyond the flight-hour threshold"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to specific Italian-made aircraft models (SIAI Marchetti S.205 and S.208 series).\n\n**What it does:**\n- Requires owners/operators to inspect and maintain the **landing gear actuator damper** (a rubber component that cushions the landing gear mechanism) according to manufacturer instructions.\n- The damper can deform over time. If this happens alongside a minor misalignment in the landing gear system, the landing gear might not lock properly when extended — a serious safety risk.\n\n**Who must comply:**\n- Owners of the affected aircraft models: S.205-18R, -20R, -22R; S.208 and S.208A.\n\n**When to act:**\n- **Newer aircraft** (under 500 flight hours): Inspect at the 500-hour maintenance check.\n- **Older aircraft** (over 500 flight hours): Inspect within 100 flight hours after 11 November 1993, then every 100 flight hours ongoing.\n\n**Why it matters:**\nLanding gear failure on approach or landing can be catastrophic. This directive prevents accidents by catching damper damage before it causes an unsafe \"down-lock\" condition (where the gear appears down but isn't securely locked)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive's scope—applying to the listed SIAI Marchetti models and mandating action per Service Bulletin 205B49 Revision B on a specified inspection schedule—matches the stated intent in the background to address reports of damaged landing gear actuator rubber dampers. There is no indication in the text that the scope was broadened or narrowed from that stated safety purpose."},"complexity_factors":["Requires following an external technical document (SIAI Marchetti Service Bulletin 205B49 Revision B) rather than containing full technical instructions (Requirement).","Different compliance timing depending on accrued airframe hours (<500 hours vs >500 hours) and a recurring 100‑hour interval for certain aircraft (Compliance).","Technical subject matter (landing gear actuator rubber damper) requires qualified maintenance personnel and possibly parts, increasing implementation complexity.","Time‑based enforcement creates ongoing administrative tracking for operators (logbook/hours monitoring).","Limited textual detail in the AD about the corrective actions shifts practical interpretation to manufacturers' bulletin, adding potential for variation in execution."],"plain_english_summary":"This AD mandates owners/operators of SIAI Marchetti S.205-18R, -20R, -22R and S.208/S.208A aeroplanes to inspect and act on the landing‑gear actuator rubber damper in accordance with SIAI Marchetti Service Bulletin 205B49 Rev B. It requires the work at the 500‑hour inspection (or within 100 hours if already over 500 hours as of 11 Nov 1993) and recurring every 100 hours. The rule responds to reported damper damage that could cause an unsafe down‑lock; compliance costs fall to operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sm-205-35-landing-gear-actuator-damper","history":"/api/acts/ad-sm-205-35-landing-gear-actuator-damper/history","analysis":"/api/acts/ad-sm-205-35-landing-gear-actuator-damper/analysis","conflicts":"/api/acts/ad-sm-205-35-landing-gear-actuator-damper/conflicts","importantCases":"/api/acts/ad-sm-205-35-landing-gear-actuator-damper/important-cases","documents":"/api/acts/ad-sm-205-35-landing-gear-actuator-damper/documents"}}