{"id":"F2006B07033","name":"AD/SM-205/11A - Flap Lock Mechanism - Modification","slug":"ad-sm-205-11a-flap-lock-mechanism-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48736,"registerId":"commonwealth-F2006B07033-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SM-205/11A - Flap Lock Mechanism - Modification","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)  SIAI Marchetti S205 and S208 Series Aeroplanes\n\n \n\nAD/SM-205/11A Flap Lock Mechanism - Modification 2/72\n\nApplicability: All S205 Series.\n\n \n\nDocument: 1. SIAI Marchetti SB 205B25; or\n\n \n\n2. FAA AD 70-20-1; or\n\n \n\n3. AD/SM-205/11.\n\n \n\nCompliance: Before 29 February 1972.\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\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive focused specifically on flap lock mechanisms for one aircraft series. It has not expanded beyond its original technical safety purpose. The 'A' suffix indicates this is an amended version of a previous directive (AD/SM-205/11), but the amendment appears to be administrative or clarifying rather than a scope expansion."},"complexity_factors":["Extremely short document (approximately 150 words of substantive content)","Only 1 defined applicability criterion ('All S205 Series')","Simple binary compliance structure: modify by deadline or ground aircraft","No nested exceptions, conditional logic, or cross-references to other legislation beyond three alternative technical documents","Single operational requirement with clear deadline","No interpretative provisions, penalty clauses, or administrative procedures"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) that mandates a safety modification to the flap lock mechanism on specific Italian-made aircraft.\n\n**What it does:**\n- Requires owners and operators of **SIAI Marchetti S205 series aeroplanes** to modify the flap lock mechanism (the system that keeps wing flaps in position during flight).\n\n**Who it affects:**\n- All owners, operators, and maintenance organisations responsible for **SIAI Marchetti S205 series aircraft** — these are light, single-engine Italian aircraft popular in the 1960s-70s.\n\n**Why it matters:**\n- Flap lock mechanisms prevent flaps from moving unexpectedly during flight, which could cause loss of control. This directive addresses a known safety defect.\n- **Compliance was mandatory before 29 February 1972** — meaning this is a historical directive that would have already been implemented on any surviving aircraft still in service.\n\n**How to comply:**\nOperators must follow one of three technical documents:\n- The manufacturer's Service Bulletin (SB 205B25), **or**\n- The equivalent US Federal Aviation Administration directive (FAA AD 70-20-1), **or**\n- The previous version of this Australian directive (AD/SM-205/11)\n\nThis is a **mandatory safety order** — non-compliance would have made the aircraft unairworthy and illegal to fly."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The source text does not provide the prior AD/SM-205/11's content or the earlier scope to permit a definitive comparison. AD/SM-205/11A mandates a flap lock mechanism modification for all S205 series and explicitly allows compliance by following AD/SM-205/11 (listed among the acceptable documents). The AD text supplied does not show an expansion or contraction of scope relative to prior material, so a change in scope cannot be determined from this source alone."},"complexity_factors":["References external technical documents rather than including technical detail in the AD itself (operators must obtain and follow one of three documents).","Fixed, near-term compliance deadline imposes scheduling pressure (specified: before 29 February 1972).","Applicability to an entire model series (all S205 Series) creates a fleet-wide compliance requirement.","Multiple acceptable compliance documents create a choice for operators that may affect costs or methods.","Absence of stated rationale or enforcement details in the AD increases need to consult referenced material or regulator for clarification."],"plain_english_summary":"This AD mandates modification of the flap‑lock mechanism on all SIAI Marchetti S205 series aeroplanes, to be completed by 29 February 1972. Compliance requires carrying out the change in accordance with one of three referenced documents (SIAI SB 205B25, FAA AD 70‑20‑1, or AD/SM‑205/11). Owners/operators bear the cost and logistical burden of scheduling and performing the work."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sm-205-11a-flap-lock-mechanism-modification","history":"/api/acts/ad-sm-205-11a-flap-lock-mechanism-modification/history","analysis":"/api/acts/ad-sm-205-11a-flap-lock-mechanism-modification/analysis","conflicts":"/api/acts/ad-sm-205-11a-flap-lock-mechanism-modification/conflicts","importantCases":"/api/acts/ad-sm-205-11a-flap-lock-mechanism-modification/important-cases","documents":"/api/acts/ad-sm-205-11a-flap-lock-mechanism-modification/documents"}}