{"id":"F2006B08550","name":"AD/CHA/23 Amdt 4 - Wing Spars","slug":"ad-cha-23-amdt-4-wing-spars","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51344,"registerId":"commonwealth-F2006B08550-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CHA/23 Amdt 4 - Wing Spars","content":"![](image.001.png)\n\n![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/CHA/23 Amdt 2 and issues the following AD under subregulation 39.1 (1) of CAR 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\nAmerican Champion (Aeronca, Bellanca) Series Aeroplanes\n\nAD/CHA/23\n\nAmdt 3\n\n  \nWing Spars 3/2001\n\nApplicability: Group 1 aircraft: ACAC Models 7AC, 7ACA, S7AC, 7BCM (L-16A), 7CCM (L- 16B), S7CCM, 7DC, S7DC, 7EC, S7EC, 7FC, 7JC, 11AC, S11AC, 11BC, S11BC,\n\n11CC, and S11CC aircraft that have not been modified to incorporate an engine with greater than 90 horsepower.\n\nGroup 2 aircraft: ACAC Models 7ECA, 7GC, 7GCA, 7GCAA, 7GCB, 7GCBA, 7GCBC, 7HC, 7KC, 7KCAB, 8GCBC, and 8KCAB aircraft; and any of the Group 1 aircraft that have been modified to incorporate an engine with greater than 90 horsepower.\n\nRequirement: 1. Perform a detailed visual inspection of the entire length of the front and rear wood wing spars for cracks, compression cracks, longitudinal cracks through the boltholes or nail holes, or loose or missing rib nails. Accomplish in accordance with the instructions in ACAC Service Letter No. 406, Revision A, dated May 6, 1998. This service letter specifies, as an FAA-approved inspection option, using a high-intensity flexible light (e.g., “Bend-A-Light”). A regular flashlight must not be used for this portion of the inspection.\n\n    2. If, after 22 March 2001 any aircraft is involved in an accident/incident that involves wing damage (e.g., wing surface deformations such as abrasions, gouges, scratches, or dents, etc.), accomplish the inspection specified in Requirement 1.\n\n    3. If any damage is found during any inspection required by this Directive, repair or replace the wood spar, in accordance with Advisory Circular 43.13-1B, Acceptable Methods, Techniques, and Practices; or other data that is FAA-approved for wing spar repair or replacement.\n\nNote : FAA AD 2000-25-02 Amdt 39-12036 refers.\n\nCompliance: 1. For Group 1 aircraft: Initially inspect at the first annual inspection that occurs 30 calendar days or more after 22 March 2001 or within the next 13 calendar months after 22 March 2001, whichever occurs later\n\nAmerican Champion (Aeronca, Bellanca) Series Aeroplanes\n\nAD/CHA/23 Amdt 3 (Continued)\n\nFor Group 2 aircraft: Initially inspect at the first annual inspection that occurs 30 calendar days or more after 22 March 2001 or within the next 13 calendar months after 22 March 2001, whichever occurs later. Repetitively inspect thereafter at intervals not to exceed 500 hours time in service or 12 calendar months, whichever occurs first.\n\n    2. Before further flight after each accident/incident that involved wing damage.\n\n    3. Before further flight after the inspection where the damage is found.\n\nThis amendment becomes effective on 22 March 2001.\n\nBackground: Accidents caused by in-flight structural failure of the wings were attributed to compression failures in the wooden wing spars. Significant compression failures have also been found in other areas not addressed by FAA AD 87-18-09.\n\nAmendment 2 required repetitive inspections of the front and rear spars for damage, including installing any necessary inspection holes, and repairing or replacing any damaged spar. The FAA actions resulted from in-flight wing structural failure on one of the affected aircraft that was in compliance with AD 87-18-09, plus four other ACAC Model 8GCBC accidents and eleven service difficulty reports of compression cracked spars.\n\nAmendment 3 is issued in response to a new FAA AD which retains the actions of AD 98-05-04 for the Model 8GCBC aircraft; extends the actions to all 7,8, and 11 series aircraft, and incorporates alternative methods of accomplishing the actions. The AD is the result of a review of the service history of the affected aircraft that incorporate wood wing spars and of damage found on the spars.\n\nAmendment 2 of this Airworthiness Directive became effective on 12 August 1999. Amendment 1 of this Airworthiness Directive became effective on 16 May 1991.\n\nThe original issue of this Airworthiness Directive became effective on 3 December 1987.\n\n![Signature of David Alan Villiers Delegate of the Civil Aviation Safety Authority](image.002.png)  \n\nDavid Alan Villiers\n\n![](image.001.png)  \nDelegate of the Civil Aviation Safety Authority 9 February 2001\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 21 February 2001.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"The original 1987 directive addressed specific compression failure issues. Amendment 3 significantly expanded scope from the Model 8GCBC (covered in earlier amendments) to include all 7, 8, and 11 series aircraft with wooden wing spars. It also introduced differentiated compliance schedules (Group 1 vs Group 2), repetitive inspection requirements for higher-powered aircraft, and incorporated alternative inspection methods from FAA AD 2000-25-02. The directive evolved from a targeted fix to a comprehensive fleet-wide safety program."},"complexity_factors":["Two distinct applicability groups with different compliance schedules (Group 1 vs Group 2)","Multiple cross-references to external documents (ACAC Service Letter No. 406 Rev A, FAA AD 2000-25-02, Advisory Circular 43.13-1B)","Conditional triggers: accident/incident damage triggers additional inspection requirements","Nested timing requirements: '30 calendar days or more after 22 March 2001 or within the next 13 calendar months after 22 March 2001, whichever occurs later'","Specific technical equipment mandate (high-intensity flexible light vs regular flashlight)","Revocation of previous amendment (AD/CHA/23 Amdt 2) and incorporation of FAA regulatory history"],"plain_english_summary":"This AD orders mandatory detailed inspections of wooden wing spars on American Champion (7-, 8-, 11-series) light aircraft, using a high‑intensity flexible light, with immediate grounding and repair if cracks, compression damage, or loose/missing nails are found. It distinguishes lower‑ and higher‑powered groups for inspection cadence.\n\nIt targets owners/operators to prevent hidden compression cracks that have caused in‑flight wing failures."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"Amendment 3 broadened the AD’s reach compared with earlier versions: it retains previous actions and adds all 7, 8 and 11 series aircraft (extending beyond the earlier, narrower model set), incorporates alternative FAA‑approved inspection methods, and clarifies repetitive inspection requirements (see Background: \"extends the actions to all 7,8, and 11 series aircraft, and incorporates alternative methods of accomplishing the actions\")."},"complexity_factors":["Technical inspection standard: requires detailed visual inspection of entire spar length and use of a specific lighting tool (ACAC Service Letter No. 406, Revision A) rather than a regular flashlight.","Multiple applicability groups: different model lists for Group 1 and Group 2 with differing engine‑power treatment and compliance timing.","Compliance timing complexity: initial inspection windows tied to calendar dates and annual inspections, plus recurring intervals for Group 2 (500 flight hours or 12 months) and event‑triggered inspections after wing damage.","Dependencies on external authoritative documents: ACAC Service Letter No. 406, Advisory Circular 43.13‑1B, and reference to FAA ADs, creating cross‑referenced compliance obligations.","Repair standard and approval: repairs/replacements must follow FAA‑approved data, giving technical approvers discretion and potentially varying acceptable methods.","Operational disruption and cost: inspections may require removal of panels/creation of inspection holes and repairs can ground aircraft until FAA‑approved repairs are completed.","Legacy amendment trail: multiple amendments and retained/extended requirements create interpretive complexity for which amendment controls in specific circumstances."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of specified American Champion (Aeronca, Bellanca) 7, 8 and 11 series aeroplanes to perform detailed visual inspections of the front and rear wooden wing spars for cracks, compression damage, longitudinal cracks at bolt/nail holes, and loose or missing rib nails, using ACAC Service Letter No. 406 (including a high‑intensity flexible light). Any damaged spar must be repaired or replaced using FAA‑approved methods. Initial and recurring inspection timing differs by aircraft group; operators bear inspection and repair costs."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cha-23-amdt-4-wing-spars","history":"/api/acts/ad-cha-23-amdt-4-wing-spars/history","analysis":"/api/acts/ad-cha-23-amdt-4-wing-spars/analysis","conflicts":"/api/acts/ad-cha-23-amdt-4-wing-spars/conflicts","importantCases":"/api/acts/ad-cha-23-amdt-4-wing-spars/important-cases","documents":"/api/acts/ad-cha-23-amdt-4-wing-spars/documents"}}