{"id":"F2006B04187","name":"AD/BEECH 77/11 - Wing - Inspection, Bolt Replacement and Fatigue Life Limitation","slug":"ad-beech-77-11-wing-inspection-bolt-replacement-and-fatigue-life-limitation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43941,"registerId":"commonwealth-F2006B04187-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 77/11 - Wing - Inspection, Bolt Replacement and Fatigue Life Limitation","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)  \nBeechcraft 77 (Skipper) Series Aeroplanes\n\nAD/BEECH 77/11 Wing \\- Inspection, Bolt Replacement\n\nand Fatigue Life Limitation\n\n  \n10/82\n\nApplicability: All models.\n\nRequirement: 1. Carry out the wing structure inspection and bolt replacement as detailed in Section 57-10-00 of the Beechcraft Skipper 77 Maintenance Manual.\n\n2. Retire the wing and carry through structure from service as detailed in Section 4-00-00 of the Beechcraft Skipper 77 Maintenance Manual.\n\nCompliance: For Para. 1 - Upon or before achieving 7000 hours’ time in service. For Para. 2 \\- Upon or before achieving 12000 hours’ time in service.\n\nBackground: The wing safe fatigue life of 12000 hours has been determined by the manufacturer by full scale fatigue test, and is dependent upon replacement of certain bolts, and successful inspection results, at 7000 hours.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-purpose airworthiness directive focused specifically on wing fatigue life limits for one aircraft type. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 substantive requirements with clear time-based triggers","No defined terms section — uses plain language and references external manual sections","No nested exceptions or conditional logic","Simple binary applicability (all models)","Cross-references only to manufacturer maintenance manual sections, not to other legislation"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for **Beechcraft 77 Skipper aircraft**.\n\n**What it does:**\n- Requires owners/operators to **inspect the wing structure and replace specific bolts** once the aircraft reaches **7,000 flight hours**\n- Requires **permanent retirement of the wing and carry-through structure** (the parts that hold the wings to the fuselage) once the aircraft reaches **12,000 flight hours**\n\n**Who it affects:**\n- Anyone who owns or operates a Beechcraft 77 Skipper aeroplane in Australia\n- Maintenance engineers working on these aircraft\n\n**Why it matters:**\n- Metal aircraft parts weaken over time due to **fatigue** (repeated stress from takeoffs, landings, and turbulence)\n- The manufacturer tested these wings and determined they have a **safe lifespan of 12,000 hours** — but only if certain bolts are replaced at the halfway point (7,000 hours)\n- This directive prevents catastrophic wing failure by forcing retirement before the structure becomes unsafe\n\n**The bottom line:** If you fly or maintain a Beech 77 Skipper, you must track flight hours carefully. At 7,000 hours, inspect and replace bolts. At 12,000 hours, the wing must be permanently grounded — no exceptions."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive implements the manufacturer’s determination of wing fatigue life (Background) by mandating the inspection/bolt replacement at 7,000 hours and retirement at 12,000 hours (Requirement Paras. 1–2 and Compliance). It does not expand or narrow the technical scope beyond the manufacturer’s specified maintenance-manual procedures; rather, it makes those manufacturer determinations mandatory under the AD."},"complexity_factors":["Two discrete required actions (inspection/bolt replacement; structural retirement) with clear hour thresholds (7,000 h and 12,000 h).","Technical detail delegated to manufacturer maintenance manual sections (Section 57-10-00 and Section 4-00-00), requiring specialist maintenance procedures.","Operational logistics: tracking airframe hours, scheduling downtime and sourcing parts/labour.","Dependence on inspection outcomes (successful inspection at 7,000 h affects ability to reach 12,000 h).","Regulatory enforcement by CASA under Civil Aviation Regulations Part 39 (administrative compliance)."],"plain_english_summary":"The Civil Aviation Safety Authority requires owners/operators of Beechcraft 77 (Skipper) aircraft to have a wing inspection and specified bolt replacement by 7,000 hours, and to retire the wing and carry‑through structure by 12,000 hours. Based on the manufacturer's fatigue testing, the measures are intended to ensure wing structural safety; owners/operators bear the inspection, parts, labour and replacement costs, and must track airframe hours to remain compliant."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-77-11-wing-inspection-bolt-replacement-and-fatigue-life-limitation","history":"/api/acts/ad-beech-77-11-wing-inspection-bolt-replacement-and-fatigue-life-limitation/history","analysis":"/api/acts/ad-beech-77-11-wing-inspection-bolt-replacement-and-fatigue-life-limitation/analysis","conflicts":"/api/acts/ad-beech-77-11-wing-inspection-bolt-replacement-and-fatigue-life-limitation/conflicts","importantCases":"/api/acts/ad-beech-77-11-wing-inspection-bolt-replacement-and-fatigue-life-limitation/important-cases","documents":"/api/acts/ad-beech-77-11-wing-inspection-bolt-replacement-and-fatigue-life-limitation/documents"}}