{"id":"F2006B04170","name":"AD/BEECH 76/12 Amdt 1 - Wing Structural Inspections and Fatigue Life Limitation","slug":"ad-beech-76-12-amdt-1-wing-structural-inspections-and-fatigue-life-limitation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43923,"registerId":"commonwealth-F2006B04170-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 76/12 Amdt 1 - Wing Structural Inspections and Fatigue Life Limitation","content":"![](image.002.png)![](image.001.png)AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BEECH 76/12 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\nBeechcraft 76 (Duchess) Series Aeroplanes\n\nAD/BEECH 76/12\n\nAmdt 1\n\n  \n\nWing Structural Inspections and Fatigue Life Limitation\n\n  \n13/2002\n\nApplicability: All Models.\n\nRequirement: 1. Carry out the Mandatory Inspections as detailed in Section 57-00-00 of the Beechcraft Duchess 76 Maintenance Manual.\n\nWhen inspecting the Fuselage She ar Fittings P/N 105-420011-5 and \\-6, look for evidence of the following:\n\n    (i) Rivets working loose, sheared or missing.\n\n    (ii) Cracking in the bend radii of the Fuselage Shear Fitting.\n\n    (iii) Evidence of fretting products which will be generated if the fitting is loose and is moving relative to the fuselage skin.\n\n2. Retire the wing and carry through structure as detailed in Section 4-00-00 of the Beechcraft Duchess 76 Maintenance Manual.\n\nCompliance: For Requirement 1 \\- At the Initial Inspection and Subsequent Inspection times as detailed in the Mandatory Inspection Schedule, Chart 1, Section 57-00-00 of the Beechcraft Duchess 76 Maintenance Manual.\n\nFor Requirement 2 \\- Upon or prior to achieving 20000 hours’ time in service.\n\nThe Compliance times of the original issue of this Airworthiness Directive are not changed by this amendment.\n\nThis Amendment becomes effective on 26th December 2002.\n\nBackground: The mandatory wing inspections and fatigue life limitation are as determined by the manufacturer from the results of full scale fatigue tests.\n\nBeechcraft 76 (Duchess) Series Aeroplanes\n\nAD/BEECH 76/12 Amdt 1 (continued)\n\nAmendment 1 provides additional guidance for inspection of the Fuselage Shear Fittings. This is the result of several recent events where the fitting has been found cracked or with loose or missing rivets.\n\nThe consequences of a cracked or loose Fuselage Shear Fitting may be the loss of wing to fuselage attachment and subsequent damage to the wing and fuselage structure.\n\nThe original issue of this AD became effective on 31st March 1983.\n\n![](image.003.jpeg)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 14 November 2002\n\n![](image.002.png)The above AD is notified in the Commonwealth of Australia Gazette on 4 December 2002.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment adds specific inspection guidance for the fuselage shear fittings (AD text, Requirement 1 and Background) but does not change applicability (all models) or the compliance timing set out in the original AD (Compliance). Therefore the scope of affected aircraft and the timing obligations remain unchanged."},"complexity_factors":["Relies on an external document (Beechcraft Duchess 76 Maintenance Manual, Section 57‑00‑00 and 4‑00‑00) for the detailed inspection schedule and retirement procedure","Technical inspection criteria require detecting rivet condition, bend‑radius cracking and fretting — needs trained maintenance personnel and appropriate access/techniques","Fixed retirement threshold (20,000 hours) requires accurate time‑in‑service tracking and planning for major structural replacement","Amendment adds focused guidance (fuselage shear fittings) but does not alter compliance timing, increasing inspection specificity without changing scope","Regulatory form is an Airworthiness Directive issued under CAR 1998 subregulation 39.1(1), limiting discretionary interpretation by operators"],"plain_english_summary":"Requires operators and owners of Beechcraft 76 (Duchess) aeroplanes to carry out mandatory wing and fuselage shear‑fitting inspections according to the Beechcraft Duchess 76 Maintenance Manual and to retire the wing and carry‑through structure at or before 20,000 hours’ time in service. (Inspections: Requirement 1; Retirement: Requirement 2; Compliance: Compliance.) Operators pay for inspections and any replacement/retirement; CASA amended the AD to add inspection guidance for fuselage shear fittings after reports of cracking, loose or missing rivets."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope of the 1983 AD. It adds specific inspection guidance for fuselage shear fittings based on new incident data, but does not expand the applicability to new aircraft types, add new structural components, or alter the fundamental fatigue life limitation of 20,000 hours. The document explicitly states that compliance times from the original issue are unchanged."},"complexity_factors":["Short, single-purpose document (2 main requirements only)","Minimal defined terms — relies on external maintenance manual references rather than inline definitions","Clear structure: Applicability → Requirement → Compliance → Background","Some technical aviation terminology (e.g., 'fuselage shear fittings', 'fretting products', 'P/N 105-420011-5') but terms are industry-standard and explained through context","No nested exceptions or conditional logic — requirements apply uniformly to 'All Models'","Cross-references to external documents (Beechcraft Maintenance Manual) but these are specific and unambiguous","Single amendment layer (Amendment 1) with explicit statement that original compliance times remain unchanged"],"plain_english_summary":"This Airworthiness Directive requires owners/operators of Beechcraft 76 (Duchess) aircraft to inspect fuselage shear fittings that attach the wing to the fuselage for loose/missing rivets, cracks, and fretting, and mandates permanent retirement of the wing/internal structure at 20,000 flight hours. It aims to prevent catastrophic wing separation found in fatigue testing and incidents. Amendment 1 (Nov 2002) adds inspection guidance but keeps original compliance deadlines."},"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-beech-76-12-amdt-1-wing-structural-inspections-and-fatigue-life-limitation","history":"/api/acts/ad-beech-76-12-amdt-1-wing-structural-inspections-and-fatigue-life-limitation/history","analysis":"/api/acts/ad-beech-76-12-amdt-1-wing-structural-inspections-and-fatigue-life-limitation/analysis","conflicts":"/api/acts/ad-beech-76-12-amdt-1-wing-structural-inspections-and-fatigue-life-limitation/conflicts","importantCases":"/api/acts/ad-beech-76-12-amdt-1-wing-structural-inspections-and-fatigue-life-limitation/important-cases","documents":"/api/acts/ad-beech-76-12-amdt-1-wing-structural-inspections-and-fatigue-life-limitation/documents"}}