{"id":"F2006B08248","name":"AD/CESSNA 337/29 - Upper Shoulder Harness Adjuster Spring","slug":"ad-cessna-337-29-upper-shoulder-harness-adjuster-spring","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115517,"registerId":"commonwealth-F2006B08248-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 337/29 - Upper Shoulder Harness Adjuster Spring","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\n \n\n \n\n![](image.001.png)\n\n# AIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (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\n\n \n\nCessna 337 Series Aeroplanes\n\n \n\n# AD/CESSNA 337/29 Upper Shoulder Harness Adjuster Spring\n\n\n13/2004\n\n \n\nApplicability: Model 337, 337A, 337B, 337C, 337D, 337E, T337B, T337C, T337D, and T337E\n\naircraft, with serial numbers listed in Cessna Multi-Engine Service Bulletin (SB) MEB86-22 Revision 1, dated 28 July 2003.\n\n \n\nRequirement: 1. Inspect only the upper shoulder harness adjuster (part number 443030-401) for the presence of a retainer spring, in accordance with SB MEB86-22 Revision 1.\n\n \n\nIf a retainer spring is found during the above inspection of the upper shoulder harness adjuster (part number 443030-401), before further flight, remove the spring by cutting each side, and stamp out the -401 identification number; in accordance with SB MEB86-22 Revision 1.\n\n \n\nIf a retainer spring is not found during the above inspection of the upper shoulder harness adjuster (part number 443030-401), before further flight, make an entry in the aircraft log book showing compliance with this Directive.\n\n \n\n2. Only incorporate Cessna Accessory Kits that have been identified, inspected, and modified in accordance with the Requirement document.\n\n \n\nNote: FAA AD 2004-19-01 Amdt 39-13795 refers.\n\n \n\nCompliance: 1. Within the next 25 hours time in service or at the next annual inspection after 23 December 2004, whichever occurs first.\n\n \n\n2. As of the effective date of this Directive.\n\n \n\nNote: Compliance with SB MEB86-22 original issue, dated 21 November 1986, constitutes terminating action for the requirements of this Directive, if shoulder harness adjuster part number 443030-401 was used.\n\n \n\nThis Airworthiness Directive becomes effective on 23 December 2004.\n\nCessna 337 Series Aeroplanes\n\n \n\nAD/CESSNA 337/29 (continued)\n\n \n\nBackground: The manufacturer determined that some of the shoulder harness belt adjusters included in the affected shoulder harness accessory kits may have had a small wire spring inadvertently installed on the belt friction pin. The actions required by this Directive are intended to prevent slippage of the pilot/co-pilot shoulder harness, which could result in failure of the shoulder harness to maintain proper belt length adjustment and tension.\n\n![](image.002.png)  \n\n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 12 November 2004\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![](image.001.png)  \n\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 1 December 2004.\n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope. It addresses a specific manufacturing defect in a specific part (shoulder harness adjuster spring) on specific Cessna 337 series aircraft. The directive has not expanded beyond its original safety purpose of preventing shoulder harness slippage."},"complexity_factors":["Single, clearly defined applicability (specific aircraft models and serial numbers)","Straightforward binary inspection requirement (spring present vs. absent)","Only two possible outcomes with clear actions for each","Minimal cross-referencing (only to Cessna Service Bulletin MEB86-22 and FAA AD 2004-19-01)","Simple compliance timeframe (25 hours or next annual inspection)","No nested exceptions or conditional logic beyond the spring presence check","Short document (approximately 1 page of substantive content)"],"plain_english_summary":"This safety order requires owners/operators of specified Cessna 337-series aircraft to inspect the pilot and co‑pilot upper shoulder harness adjusters for a small, unintended wire spring that can let the harness slip in a crash. If the spring is found it must be removed before further flight; if not, the inspection must be logged.  \n\nCompliance is required within 25 flight hours or at the next annual inspection after 23 December 2004. This addresses a direct life‑safety risk."},"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"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD implements the manufacturer’s corrective action described in SB MEB86-22 Rev 1 and confines action to listed models/serials and the specific part number (443030-401). It does not broaden applicability beyond those aircraft or add new mandated changes; compliance with the original SB is stated as terminating action for affected parts (Note)."},"complexity_factors":["Narrow technical focus: single part (upper shoulder harness adjuster P/N 443030-401) and single defect (retainer spring) — simplifies assessment (Requirement 1).","Targeted applicability: only specified Cessna 337 variants and serial numbers listed in SB MEB86-22 Rev 1 — reduces universe of affected aircraft (Applicability).","Prescriptive corrective action: simple inspection and cutting/removal and stamping procedure — low technical execution complexity but requires hands-on work and tooling (Requirement 1).","Compliance timing: short mandatory window (within 25 hours TIS or at next annual) concentrates workload for operators (Compliance 1).","Record-keeping obligation: logbook entry required if spring absent, and stamping of part if modified — modest administrative burden (Requirement 1).","Kit control rule: restriction that only accessory kits identified, inspected and modified per the Requirement may be incorporated imposes supply/installation controls on operators and maintenance providers (Requirement 2).","Reference to external documents (Cessna SB MEB86-22 Rev 1 and FAA AD 2004-19-01) means compliance depends on consulting and following another technical document — adds dependency risk."],"plain_english_summary":"This Airworthiness Directive requires operators of certain Cessna 337 series aircraft (serial numbers listed in Cessna SB MEB86-22 Rev 1) to inspect the upper shoulder harness adjuster (P/N 443030-401) for a small retainer spring and, if present, cut it off and stamp out the -401 ID; if not present, log compliance. CASA issued the AD; aircraft owners/operators pay for inspections, any modifications and record-keeping and must only install accessory kits that have been inspected and modified per the service bulletin, within 25 flight hours or at the next annual inspection."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-337-29-upper-shoulder-harness-adjuster-spring","history":"/api/acts/ad-cessna-337-29-upper-shoulder-harness-adjuster-spring/history","analysis":"/api/acts/ad-cessna-337-29-upper-shoulder-harness-adjuster-spring/analysis","conflicts":"/api/acts/ad-cessna-337-29-upper-shoulder-harness-adjuster-spring/conflicts","importantCases":"/api/acts/ad-cessna-337-29-upper-shoulder-harness-adjuster-spring/important-cases","documents":"/api/acts/ad-cessna-337-29-upper-shoulder-harness-adjuster-spring/documents"}}