{"id":"F2006B05034","name":"AD/CESSNA 180/15 Amdt 4 - Rear Spar","slug":"ad-cessna-180-15-amdt-4-rear-spar","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44944,"registerId":"commonwealth-F2006B05034-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 180/15 Amdt 4 - Rear Spar","content":"![](image.001.png)\n\n![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nOn the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/CESSNA 180/15 Amdt 3 and issues the following AD under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)\n\nCessna 180, 182 and Wren 460 Series Aeroplanes\n\nAD/CESSNA 180/15\n\nAmdt 4\n\n  \nRear Spar 8/2004\n\nApplicability: All models except those with rear spars P/Nos. 0523400-90 L.H. and \\-91 R.H.; 0523400-111 L.H. and -112 R.H.; 0726014-1 L.H. and 0726014-2 R.H.\n\nNote 1: Restart series Cessna 182s have rear spars part numbers 0726014-1 L.H. and 0726014-2 R.H.\n\nRequirement: 1. Modify the rear spar root, of the left and right mainplanes on all aeroplanes engaged in agricultural operations in accordance with Rex Aviation Drawing RA- 491 or an alternative scheme approved by the Secretary.\n\n    2. Inspect the mainplane rear spar web for fatigue cracks in the root area. These cracks originate in the radius which is located under the attachment fittings. This inspection shall be carried out using a magnifying glass of at least 4X’ magnification or alternatively a device such as the “Syte Ade” may be employed.\n\n    3. Inspect the upper flange of the rear spar channel at the outer end of the attachment fitting. This can be done via the flap bay inner inspection panel.\n\nSince the trailing edge root end fits closely to the spar, it may be difficult to detect possible cracks, therefore when doubt exists the trailing edge root end rib shall be removed for more detailed inspection.\n\nNote 2: The affected area is illustrated in Rex Aviation Technical Memorandum No. 12 dated 10 May 1960.\n\nCompliance: Para. 1 \\- Unless already accomplished, before further flight after the effective date of this Airworthiness Directive.\n\nParas. 2 and 3 \\- Aeroplanes modified to Rex Aviation Drawing RA-491 \\- at intervals not exceeding 500 hours time in service.\n\nFor all other aeroplanes: at intervals not exceeding 100 hours time in service. This Amendment becomes effective on 5 August 2004.\n\nCessna 180, 182 and Wren 460 Series Aeroplanes\n\nAD/CESSNA 180/15 Amdt 4 (continued)\n\nBackground: Amendment 4 has been issued to remove the requirement for Restart series Cessna 182 aircraft to comply with this directive. Restart series C182s have a different part number rear spar to the original models.\n\n![](image.002.png)  \n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 21 June 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 14 July 2004.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment 4 narrows the AD’s scope by excluding Restart series Cessna 182 aircraft that have different rear-spar part numbers (Background; Applicability). The AD otherwise maintains the same modification and inspection requirements and revokes the prior amendment (Amdt 3)."},"complexity_factors":["Applicability carved out by specific rear-spar part numbers, requiring part-number checks before action (Applicability).","Different compliance timing depending on whether the aeroplane is modified (Compliance: Para. 1; Paras. 2 and 3).","Multiple inspection methods authorised (4X magnifying glass or equivalent device such as 'Syte Ade') and an instruction to remove the trailing-edge root rib when doubt exists (Requirement: Paras. 2–3).","Delegate/Secretary discretion to accept alternative corrective schemes (Requirement 1: 'or an alternative scheme approved by the Secretary').","Immediate mandatory action for modification ('before further flight'), creating an urgent compliance burden for affected operators (Compliance: Para. 1).","Replacement of an earlier amendment (revocation of Amdt 3 and issuance of Amdt 4), which can affect who remains in scope (Background)."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of Cessna 180, 182 and Wren 460 series aeroplanes (except those with specified rear-spar part numbers) to modify the rear-spar root for agricultural aircraft and to perform recurring inspections for fatigue cracks in the rear-spar root area. The modification must be done before further flight; inspection intervals are 500 hours if modified and 100 hours if not, and an alternative repair scheme may be approved by the Secretary."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment narrows the scope slightly by exempting Restart series Cessna 182s, but remains tightly focused on its original purpose: addressing rear spar fatigue in specific Cessna aircraft. The core safety objective (preventing spar failure) is unchanged since the original AD."},"complexity_factors":["Short, single-purpose instrument (approximately 400 words)","Only 4 defined part numbers in the applicability exclusion","Clear, numbered requirements with straightforward compliance deadlines","Single cross-reference to external technical document (Rex Aviation Drawing RA-491)","No nested conditional logic or exceptions to exceptions","Plain language background section explaining the amendment purpose"],"plain_english_summary":"This CASA safety order targets Cessna 180, 182 and Wren 460 series aeroplanes (excluding Cessna 182s fitted with the newer \"Restart\" rear spar). It mandates a one‑time rear spar root modification for agricultural aircraft and regular fatigue inspections of the rear spar web and upper flange for all affected aeroplanes, with shorter inspection intervals if unmodified.\n\nCompliance is required before the next flight if the modification hasn't been done. The measure prevents wing‑spar fatigue cracks that could cause structural failure and catastrophic accidents."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-180-15-amdt-4-rear-spar","history":"/api/acts/ad-cessna-180-15-amdt-4-rear-spar/history","analysis":"/api/acts/ad-cessna-180-15-amdt-4-rear-spar/analysis","conflicts":"/api/acts/ad-cessna-180-15-amdt-4-rear-spar/conflicts","importantCases":"/api/acts/ad-cessna-180-15-amdt-4-rear-spar/important-cases","documents":"/api/acts/ad-cessna-180-15-amdt-4-rear-spar/documents"}}