{"id":"F2006B05028","name":"AD/CESSNA 177/33 - Upper Shoulder Harness Adjuster Spring","slug":"ad-cessna-177-33-upper-shoulder-harness-adjuster-spring","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44938,"registerId":"commonwealth-F2006B05028-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 177/33 - Upper Shoulder Harness Adjuster Spring","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 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\nCessna 177 Series Aeroplanes\n\nAD/CESSNA 177/33 Upper Shoulder Harness\n\nAdjuster Spring\n\n  \n13/2004\n\nApplicability: Models 177, 177A, and 177B aircraft, with serial numbers listed in Cessna Single Engine Service Bulletin (SB) SEB86-8 Revision 1, dated 28 July 2003.\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 SEB86-8 Revision 1.\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 SEB86-8 Revision 1.\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\n2. Only incorporate Cessna Accessory Kits that have been identified, inspected, and modified in accordance with the Requirement document.\n\nNote: FAA AD 2004-19-01 Amdt 39-13795 refers.\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\n2. As of the effective date of this Directive.\n\nNote: Compliance with SB SEB86-8 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\nThis Airworthiness Directive becomes effective on 23 December 2004.\n\nCessna 177 Series Aeroplanes\n\nAD/CESSNA 177/33 (continued)\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\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 10 November 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 1 December 2004.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive is limited to the manufacturer-identified unsafe condition affecting shoulder harness adjuster part 443030‑401 on listed Cessna 177 series serial numbers and accessory kits. It does not broaden affected aircraft or require unrelated modifications; it allows terminating action where the original SB work was already completed."},"complexity_factors":["Narrow applicability to specific models and serial numbers (Applicability — SB SEB86‑8 Rev 1).","Single, discrete mechanical remedy (inspect; cut spring; stamp ID) keeps technical complexity low (Requirement 1).","Recordkeeping obligation if no spring is found (Requirement 1 — aircraft log book entry).","Prohibition on fitting uninspected/ unmodified accessory kits increases operational control burdens (Requirement 2).","Compliance deadline is short and binary (25 hours TIS or next annual inspection) but straightforward (Compliance).","Cross-references to the Cessna Service Bulletin and FAA AD require users to consult external documents (Notes).","Terminatory clause if earlier SB original-issue work was done introduces a conditional compliance pathway (Note: terminating action).","Legal basis cited (CASR subregulation 39.1(1)) fixes administrative authority but does not add procedural complexity."],"plain_english_summary":"This Airworthiness Directive requires operators of Cessna 177/177A/177B aircraft listed in Cessna SB SEB86‑8 Rev 1 to inspect the upper shoulder harness adjuster (part 443030‑401); if a small retainer spring is present, cut it off, stamp out the -401 ID, and record the action. It also prohibits fitting accessory kits unless they’ve been inspected and modified per the Service Bulletin.\n\nCASA states the measure prevents harness slippage. Owners/operators pay inspection and modification costs; compliance is required within 25 flight hours or at the next annual inspection."},"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":2,"scope_assessment":{"changed":false,"description":"N/A - This is a standalone Airworthiness Directive with no evidence of scope creep; it addresses a single identified safety defect in a specific aircraft part as originally intended."},"complexity_factors":["Single, specific mechanical issue (one part number)","Clear binary decision tree (spring present vs. not present)","Only 2 defined compliance paths","Minimal cross-referencing (one Cessna Service Bulletin and one FAA AD mentioned in notes only)","Straightforward applicability (3 specific aircraft models by serial number)","Single compliance timeframe with simple 'whichever occurs first' condition"],"plain_english_summary":"This CASA safety order requires owners/operators of Cessna 177, 177A and 177B aircraft to inspect upper shoulder-harness adjusters (P/N 443030-401) for an inadvertent 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, log the inspection. Compliance is within 25 flight hours or at the next annual after 23 Dec 2004. It’s a critical life‑safety fix."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-177-33-upper-shoulder-harness-adjuster-spring","history":"/api/acts/ad-cessna-177-33-upper-shoulder-harness-adjuster-spring/history","analysis":"/api/acts/ad-cessna-177-33-upper-shoulder-harness-adjuster-spring/analysis","conflicts":"/api/acts/ad-cessna-177-33-upper-shoulder-harness-adjuster-spring/conflicts","importantCases":"/api/acts/ad-cessna-177-33-upper-shoulder-harness-adjuster-spring/important-cases","documents":"/api/acts/ad-cessna-177-33-upper-shoulder-harness-adjuster-spring/documents"}}