{"id":"F2006B08341","name":"AD/CESSNA 400/55 - Passenger Seat Installation - Inspection","slug":"ad-cessna-400-55-passenger-seat-installation-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115748,"registerId":"commonwealth-F2006B08341-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 400/55 - Passenger Seat Installation - Inspection","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 400 Series Aeroplanes\n\n \n\nAD/CESSNA 400/55 Passenger Seat Installation - Inspection 9/78\n\nApplicability: All models: 402B with S/Nos. 402B-0301 to 402B-1332; 404 with S/Nos. 404-0001 to 404-0223; 414 with S/Nos. 414-0251 and up; 414A with S/Nos. 414A-0001 to 414A-0042; 421 with S/Nos. 421-0001 and up; 421A with S/Nos. 421A-0001 and up; 421B with S/Nos. 421B-0001 and up; 421C with S/Nos. 421C-0001 to 421C-0478.\n\n \n\nDocument: Cessna SL ME78-17 (FAA AD 78-13-05 Amdt. 39-3250 refers). Compliance:  Within 100 hours time in service after 30 September 1978.\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":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The supplied instrument specifies applicability (models and serial numbers), the referenced document(s) (Cessna SL ME78-17; FAA AD 78-13-05 Amdt. 39-3250) and a specific compliance window (within 100 hours time in service after 30 September 1978). The text provided contains no indication that the scope (affected aircraft or compliance requirement) has been altered from what is shown here. Determining any change from a prior instrument would require comparison with earlier versions, which are not included in the supplied text."},"complexity_factors":["Multiple model and serial-number ranges listed under Applicability, requiring careful cross-checking of each aircraft's serial number.","Compliance deadline is time-based (within 100 hours time in service after a specific calendar date), requiring operators to calculate and track hours in service.","Substantive inspection procedures are not included in the text and are only available by cross-reference to Cessna SL ME78-17 and the FAA AD, so implementers must obtain external documents.","Reference to an FAA AD and a manufacturer service letter creates dependency on external documents that may contain corrective-action options or exceptions.","Historic compliance date (30 September 1978) may create retrospective interpretation or record-keeping demands for operators with long operational histories."],"plain_english_summary":"This Airworthiness Directive mandates an inspection of passenger seat installations on specified Cessna 400‑series aeroplanes, to be completed within 100 hours time‑in‑service after 30 September 1978. Compliance is achieved by following the referenced Cessna service letter (SL ME78‑17) and FAA AD 78‑13‑05. It affects aircraft owners/operators and maintenance organisations, who bear inspection costs, any repairs found, and associated downtime; non‑compliance renders the aircraft non‑conforming."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-limited safety directive from 1978 with a narrow, specific purpose. It has not expanded beyond its original scope of requiring seat installation inspections on specific Cessna models."},"complexity_factors":["Single, specific technical requirement (seat inspection)","Limited applicability — only 6 aircraft models with defined serial number ranges","No defined terms section or interpretation provisions","Simple compliance deadline (100 hours time in service)","No conditional logic, exceptions, or nested provisions","Cross-reference to only one external document (Cessna service bulletin)","Extremely short — approximately 150 words of substantive content"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for specific Cessna aircraft.\n\n**What it requires:** Owners and operators of certain Cessna 400-series twin-engine aircraft must inspect how passenger seats are installed. This follows a Cessna service bulletin (SL ME78-17) and a corresponding US Federal Aviation Administration directive.\n\n**Who it affects:** Specific serial numbers of Cessna models 402B, 404, 414, 414A, 421, 421A, 421B, and 421C — generally older aircraft manufactured in the 1970s.\n\n**When to comply:** Within 100 hours of flying time after 30 September 1978 (a deadline long since passed, meaning this should already have been done).\n\n**Why it matters:** Seat installation defects can cause seats to fail or detach during turbulence or emergency landings, injuring passengers. This directive ensures seats are properly anchored to the aircraft structure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-400-55-passenger-seat-installation-inspection","history":"/api/acts/ad-cessna-400-55-passenger-seat-installation-inspection/history","analysis":"/api/acts/ad-cessna-400-55-passenger-seat-installation-inspection/analysis","conflicts":"/api/acts/ad-cessna-400-55-passenger-seat-installation-inspection/conflicts","importantCases":"/api/acts/ad-cessna-400-55-passenger-seat-installation-inspection/important-cases","documents":"/api/acts/ad-cessna-400-55-passenger-seat-installation-inspection/documents"}}