{"id":"F2006B04993","name":"AD/CESSNA 170/64 - Lower Forward Doorpost","slug":"ad-cessna-170-64-lower-forward-doorpost","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44890,"registerId":"commonwealth-F2006B04993-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 170/64 - Lower Forward Doorpost","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)  \nCessna 170, 172, F172, FR172 and 175 Series Aeroplanes\n\nAD/CESSNA 170/64 Lower Forward Doorpost 10/98\n\nApplicability: Cessna model 172R aeroplanes, serial numbers 17280004 through 17280016, 17280018 through 17280050, 17280052 through 17280058, 17280060 through\n\n17280062, 17280064, 17280066 through 17280082, 17280085 through 17280099,\n\n17280101 through 17280113, 17280115, 17280116, 17280118 through 17280125,\n\n17280128 through 17280131 and 17280138.\n\nRequirement: Modify the lower forward doorpost by installing the specified rivets in accordance with Cessna Service Bulletin (SB) No. SB97-53-02, dated September 15, 1997.\n\nNote: FAA AD 98-14-07 refers.\n\nCompliance: Unless already accomplished, modify before 100 hours time in service after 10 September 1998. Certification in the aircraft log book of compliance with the requirements of the referenced Cessna SB, on or before 10 September 1998, satisfies the requirement of this directive and may be used to certify compliance with this directive.\n\nThis airworthiness directive becomes effective on 10 September 1998.\n\nBackground: This directive has been issued to require modification of the forward lower doorpost by installing rivets. The directive is the result of a report by Cessna that some rivets were not installed during manufacture. This may reduce the structural rigidity of the affected area, leading to structural cracking.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive remains tightly scoped to its original purpose: addressing a specific manufacturing defect in a limited production run of Cessna aircraft. The serial number specificity and single repair requirement show no scope creep."},"complexity_factors":["Single, specific mechanical requirement (install rivets per manufacturer bulletin)","Limited applicability — only one model variant (172R) with explicitly listed serial numbers","Simple compliance deadline (100 hours time in service after effective date)","No nested exceptions or conditional logic — one straightforward exemption for pre-existing compliance","Short document (under 300 words)","Only one defined term implicitly used ('time in service')","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998 and a reference to the equivalent FAA directive"],"plain_english_summary":"This safety order requires owners/operators of about 70 specific Cessna 172R aircraft (serials listed) to install missing rivets in the lower forward doorpost per Cessna Service Bulletin SB97-53-02 to prevent structural cracking. The work must be completed before the aeroplane accrues 100 flight hours after 10 September 1998 and recorded in the aircraft logbook.\n\nIf the repair was completed and logged before 10 September 1998, no further action is required."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive implements the manufacturer’s corrective action for specific serial-numbered aircraft by requiring rivet installation per the Cessna service bulletin. It confines the requirement to the identified aircraft and the single modification; the text does not expand or broaden the scope beyond that original corrective intent (Applicability; Requirement; Background)."},"complexity_factors":["Narrow, enumerated applicability – affects a defined list of Cessna 172R serial numbers (Applicability).","Single, discrete technical action – install specified rivets per a Cessna Service Bulletin (Requirement: SB97-53-02).","Dependence on manufacturer documentation for the exact procedure and parts (Requirement reference to Cessna SB).","Short compliance metric tied to flight hours and a calendar reference, plus an alternative of prior logbook certification (Compliance).","Compliance imposes direct costs and operational downtime on owners/operators and requires qualified maintenance personnel (Compliance / Background).","Regulatory enforcement rests with CASA; limited administrative discretion in implementation beyond accepting SB certification (Compliance).","Safety risk present if unmodified (structural cracking), which creates potential for urgent grounding or expedited maintenance (Background).","Cross-reference to FAA AD increases regulatory harmonisation and may affect parts/procedures sourcing (Note/FAA AD reference)."],"plain_english_summary":"This directive requires installing specified rivets in the lower forward doorpost on certain Cessna 172R serial numbers to restore structural rigidity (Requirement: Cessna SB No. SB97-53-02). Owners/operators must arrange the modification and logbook certification within 100 flight hours after 10 September 1998 (Compliance). They pay for the work, must use qualified maintenance following the manufacturer’s service bulletin, and face regulatory enforcement if they do not comply."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-170-64-lower-forward-doorpost","history":"/api/acts/ad-cessna-170-64-lower-forward-doorpost/history","analysis":"/api/acts/ad-cessna-170-64-lower-forward-doorpost/analysis","conflicts":"/api/acts/ad-cessna-170-64-lower-forward-doorpost/conflicts","importantCases":"/api/acts/ad-cessna-170-64-lower-forward-doorpost/important-cases","documents":"/api/acts/ad-cessna-170-64-lower-forward-doorpost/documents"}}