{"id":"F2006B11413","name":"AD/OPTICA/1 - Flying Control System Bellcrank Assemblies","slug":"ad-optica-1-flying-control-system-bellcrank-assemblies","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57320,"registerId":"commonwealth-F2006B11413-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/OPTICA/1 - Flying Control System Bellcrank Assemblies","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)  \nFLS Aerospace OA7 Optica Series Aeroplanes\n\nAD/OPTICA/1 Flying Control System Bellcrank Assemblies 2/94\n\nApplicability: Model OA7 Optica aircraft up to and including constructors number OA7-021. Requirement: 1. Inspect in accordance with FLS Aerospace Service Bulletin B2/MSB/1.\n\n2. Incorporate modification Kit Set B2/MKS/MSB/1\n\nNote: UK CAA AD 015-08-93 refers.\n\nCompliance: 1. At or before the next 50 hour inspection after 3 February 1994, and thereafter at each 50 hour inspection until modification Kit Set B2/MKS/MSB/1 is incorporated.\n\n2. Unless already accomplished, prior to 3 February 1995.\n\nBackground: There have been several instances, after minimal system operation, of the failure of the bonding of the bearing shells to the space tubes used in the bellcrank assemblies. The bearing shells are then able to work free of the bushes at either end of the bellcranks.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, targeted airworthiness directive addressing a specific mechanical defect in a specific aircraft model. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (under 300 words)","Only 2 substantive requirements with clear deadlines","Single defined applicability criterion (constructor number)","No nested conditional logic or cross-references to other legislation","Single external reference to UK CAA directive for context only","Plain language background explanation included"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to a specific type of light aircraft called the **FLS Aerospace OA7 Optica** (specifically those built up to serial number OA7-021).\n\n**What it requires:**\n- **Inspection:** Owners or operators must check the flying control bellcrank assemblies (mechanical linkages that help move the aircraft's control surfaces) at every 50-hour maintenance interval, starting from early 1994, until a permanent fix is installed.\n- **Modification:** A specific repair kit must be installed by February 1995 if it hasn't been done already.\n\n**Why it matters:**\nThe bearing shells (metal sleeves that allow smooth pivoting) in these bellcranks can come loose from their mounting tubes with minimal use. If they detach during flight, the pilot could lose control of the aircraft. This directive prevents potential accidents by forcing inspections and a permanent repair.\n\n**Who must comply:**\nAnyone operating or maintaining these specific Optica aircraft in Australia."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive, as written, addresses the specific failure mode described (bonding failures of bearing shells in bellcrank assemblies) by prescribing inspections until a defined modification is fitted and setting a deadline for that modification (Background; Requirement; Compliance). There is no indication in the text that the scope has been broadened or narrowed from the instrument’s stated purpose."},"complexity_factors":["Narrow and specific applicability (only OA7 Optica aircraft up to constructor number OA7-021) (Applicability)","Two clear required actions: repeated inspection per a service bulletin and a one‑off modification kit installation (Requirement)","Fixed compliance deadlines and recurring inspection intervals (Compliance 1 and 2)","Reliance on external technical documents and parts: a manufacturer service bulletin and a specific modification kit must be located and followed (Requirement; Note)","Operational coordination required: scheduling recurring 50‑hour inspections until modification and arranging kit installation before the deadline (Compliance)"],"plain_english_summary":"Applies to FLS Aerospace OA7 Optica aeroplanes (constructor numbers up to OA7‑021). It requires repeated 50‑hour inspections of flying‑control bellcrank bearing shells per FLS Service Bulletin B2/MSB/1 until operators fit Kit Set B2/MKS/MSB/1, which must be installed by 3 February 1995. Issued because bearing shells have unbonded in service, risking bellcrank failure. Owners/operators pay inspection and kit/installation costs; the rule shifts behaviour toward the one‑off modification to avoid ongoing inspection burden."}},"importantCases":[],"_links":{"self":"/api/acts/ad-optica-1-flying-control-system-bellcrank-assemblies","history":"/api/acts/ad-optica-1-flying-control-system-bellcrank-assemblies/history","analysis":"/api/acts/ad-optica-1-flying-control-system-bellcrank-assemblies/analysis","conflicts":"/api/acts/ad-optica-1-flying-control-system-bellcrank-assemblies/conflicts","importantCases":"/api/acts/ad-optica-1-flying-control-system-bellcrank-assemblies/important-cases","documents":"/api/acts/ad-optica-1-flying-control-system-bellcrank-assemblies/documents"}}