{"id":"F2006B05172","name":"AD/CESSNA 188/36 - Vertical Fin Rear Spar","slug":"ad-cessna-188-36-vertical-fin-rear-spar","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":45307,"registerId":"commonwealth-F2006B05172-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 188/36 - Vertical Fin Rear Spar","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)  Cessna 188 (Agwagon) Series Aeroplanes\n\n \n\nAD/CESSNA 188/36 Vertical Fin Rear Spar 12/80 Applicability:              Model 188 with S/Nos. 18801375 to 18803725 and T18803307T to T18803725T. Requirement:               Action in accordance with Cessna SIL No. SE80-85.\n\nCompliance: Within 100 hours time in service after 31 December 1980.\n\n \n\nBackground: Overseas, cracks have been found in the flanges and web of the spar below the lower rudder hinge.\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, targeted airworthiness directive addressing a specific structural defect in specific aircraft. It has not expanded beyond its original purpose of mandating inspection/repair of the vertical fin rear spar on affected Cessna 188 aircraft."},"complexity_factors":["Very short document (approximately 150 words)","Only 3 defined elements: applicability (serial number ranges), requirement (reference to external document), and compliance deadline","No nested conditional logic or exceptions","Single cross-reference to external Cessna document (SIL No. SE80-85)","Straightforward command structure: identify affected planes → do this action → by this deadline"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for specific Cessna 188 agricultural aircraft.\n\n**What it does:**\n- Requires owners/operators of certain Cessna 188 \"Agwagon\" planes to inspect and repair the **vertical fin rear spar** (a structural part at the back of the tail that helps keep the plane stable)\n- The directive references a specific Cessna Service Information Letter (SIL No. SE80-85) that details what actions to take\n\n**Who it affects:**\n- Owners and operators of Cessna Model 188 aircraft with serial numbers between 18801375 to 18803725, and T18803307T to T18803725T\n\n**Why it matters:**\n- **Safety critical:** Cracks had been discovered overseas in the flanges and web of this spar (the metal parts below where the rudder attaches). If this structural part fails in flight, the pilot could lose control of the aircraft\n- **Mandatory compliance:** Aircraft must be fixed within 100 hours of flying time after 31 December 1980\n\n**In short:** This is a \"fix it or ground it\" safety order preventing tail structural failures on specific crop-dusting planes."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope is limited to specific Cessna 188 serial numbers and requires compliance with Cessna SIL No. SE80-85 within a fixed 100-hour window. The text does not indicate any change from that stated scope; it sets a targeted, time-bound maintenance requirement in response to identified cracking (Applicability; Requirement; Compliance; Background)."},"complexity_factors":["Narrow applicability defined by specific serial number ranges (Applicability)","Mandatory compliance reference to an external document (Cessna SIL No. SE80-85) rather than containing technical detail (Requirement)","Short, specific compliance window (100 hours after 31 December 1980) creating operational scheduling constraints (Compliance)","Limited descriptive detail in the AD about the inspection/repair steps, tolerances, or operational permissions—dependence on the SIL (Requirement)","Clear stated technical fault (cracks in flanges and web below lower rudder hinge) but no quantified risk assessment in the AD (Background)"],"plain_english_summary":"This instrument mandates owners/operators of specified Cessna 188 (Agwagon) aeroplanes (listed serial numbers) to carry out the inspections/repairs set out in Cessna Service Information Letter No. SE80‑85, to be completed within 100 hours TIS after 31 December 1980. It responds to overseas reports of cracks in the vertical fin rear spar; operators bear the cost and scheduling burden, and must obtain and follow the SIL for technical details."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-188-36-vertical-fin-rear-spar","history":"/api/acts/ad-cessna-188-36-vertical-fin-rear-spar/history","analysis":"/api/acts/ad-cessna-188-36-vertical-fin-rear-spar/analysis","conflicts":"/api/acts/ad-cessna-188-36-vertical-fin-rear-spar/conflicts","importantCases":"/api/acts/ad-cessna-188-36-vertical-fin-rear-spar/important-cases","documents":"/api/acts/ad-cessna-188-36-vertical-fin-rear-spar/documents"}}