{"id":"F2006B04197","name":"AD/BEECH 77/7 Amdt 1 - Shoulder Harness Attach Bracket","slug":"ad-beech-77-7-amdt-1-shoulder-harness-attach-bracket","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43953,"registerId":"commonwealth-F2006B04197-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 77/7 Amdt 1 - Shoulder Harness Attach Bracket","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\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Beechcraft 77 (Skipper) Series Aeroplanes\n\n \n\nAD/BEECH 77/7\n\nAmdt 1\n\n\nShoulder Harness Attach Bracket 9/81\n\n \n\nApplicability: All model 77 with S/Nos. WA-3 to WA-235, WA-237, WA-238, WA-240 to WA- 254, WA-256, WA-258, WA-261 to WA-264, WA-266, WA-267 and WA-269.\n\n \n\nRequirement: Action in accordance with Beechcraft SI No. 1173, Rev. 1.\n\n \n\nNote: FAA AD 81-09-05 Amdt 39-4101 refers.\n\n \n\nCompliance: Within 100 hours’ time in service after 30 September 1981.\n\n \n\nBackground:  Requirement document extends the applicability to include additional serial numbers which may have the shoulder harness attach bracket installed with insufficient rivets and fastener edge distance.\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","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"The instrument extends the original applicability to include additional serial numbers that \"may have the shoulder harness attach bracket installed with insufficient rivets and fastener edge distance,\" indicating an expansion of the affected fleet compared with the earlier requirement (Background)."},"complexity_factors":["Narrow technical scope limited to a single component (shoulder harness attach bracket) on a single aircraft model","Clear applicability defined by a finite list of serial numbers (Applicability)","Prescriptive compliance action delegated to a single external manufacturer document (Beechcraft SI No. 1173, Rev. 1), creating a dependency on that document for technical detail (Requirement)","Short, fixed compliance period tied to aircraft time-in-service (100 hours after 30 Sept 1981) (Compliance)","Reference to an external regulatory document (FAA AD 81-09-05), requiring cross-reference for full context (Note)","Operational implementation considerations (scheduling, parts availability, maintenance capacity) increase practical complexity despite legal simplicity"],"plain_english_summary":"What this instrument does (mechanics)\n\n- It requires specified Beechcraft Model 77 (Skipper) aeroplanes to have work carried out \"in accordance with Beechcraft SI No. 1173, Rev. 1.\" (Requirement).\n- The requirement applies to all Model 77 aeroplanes with the listed serial numbers (Applicability).\n- The work must be completed within 100 hours' time in service after 30 September 1981 (Compliance).\n\nWho is affected\n\n- Aircraft owners and operators of the listed Beechcraft Model 77 serial numbers (Applicability).\n- Maintenance organisations or individuals who perform the inspection/modification called for in Beechcraft SI No. 1173, Rev. 1 (Requirement).\n\nWhy it matters (official rationale and practical effect)\n\n- The Background states the directive extends applicability to include additional serial numbers that \"may have the shoulder harness attach bracket installed with insufficient rivets and fastener edge distance.\" The directive therefore requires inspection and/or modification to ensure the shoulder harness attach bracket is properly secured (Background).\n\nCosts, incentives and who pays\n\n- Direct costs fall on the aircraft owner/operator: they must arrange the work required by the service instruction, pay for labour, any replacement fasteners or parts, and absorb aircraft downtime while the work is performed (Requirement; Compliance).\n- Maintenance providers receive the work and associated revenue; if parts are required they or the owner must source them (Requirement).\n\nCompliance burden and implementation risk\n\n- Compliance requires locating the relevant Beechcraft service instruction (SI No. 1173, Rev. 1) and following its procedures (Requirement). The AD references an external document (the Beechcraft SI) and also notes FAA AD 81-09-05, so operators must consult multiple sources to determine precise technical steps (Requirement; Note).\n- The AD imposes a fixed deadline expressed in aircraft time in service (100 hours after 30 September 1981), creating scheduling and downtime costs for operators (Compliance).\n- Practical implementation risks include availability of parts or certified maintenance capacity and record-keeping to demonstrate compliance (Requirement; Compliance).\n\nDecision rights and discretionary elements\n\n- The AD prescribes the action to be taken by reference to the Beechcraft service instruction; the regulator sets the requirement but delegates the technical method to the manufacturer document (Requirement). The AD does not provide alternative compliance methods within the text supplied; any alternative would require separate approval (implicit from the AD structure and referenced materials).\n\nEffects on private choice and market effects\n\n- Owners/operators face a choice: perform the work and continue operating the aircraft, or defer/curtail operations until the work is done; deferral is constrained by the AD's compliance deadline (Compliance).\n- The directive increases demand for maintenance work on the affected fleet while imposing a one-off compliance cost on owners/operators. This may raise short‑term maintenance spending for affected aircraft and create marginal additional business for maintenance providers (Requirement; Compliance).\n- For owners weighing repair cost versus keeping or selling an aircraft, the AD changes the short‑term economics of operating an affected airframe (Background; Requirement).\n\nScope and trade-offs\n\n- The instrument narrows in scope to a defined set of serial numbers but expands that set relative to an earlier requirement (Background). The trade-off presented is safety risk mitigation (inspection/modification of shoulder harness attach bracket) against the direct time, parts and labour costs and aircraft downtime borne by owners/operators (Background; Requirement; Compliance).\n\nSources cited in this summary (sections of the instrument)\n\n- \"Applicability: All model 77 with S/Nos. ...\" (Applicability).\n- \"Requirement: Action in accordance with Beechcraft SI No. 1173, Rev. 1.\" (Requirement).\n- \"Compliance: Within 100 hours’ time in service after 30 September 1981.\" (Compliance).\n- \"Background: Requirement document extends the applicability to include additional serial numbers which may have the shoulder harness attach bracket installed with insufficient rivets and fastener edge distance.\" (Background).\n- \"Note: FAA AD 81-09-05 Amdt 39-4101 refers.\" (Note)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"This is Amendment 1 to an existing directive. The original AD/BEECH 77/7 applied to a narrower set of serial numbers. This amendment expands the applicability to include additional serial numbers (WA-237, WA-238, WA-256, WA-258, WA-261-264, WA-266, WA-267, WA-269) that were discovered to potentially have the same manufacturing defect. The scope has grown modestly to capture more aircraft, but remains tightly focused on the single safety issue."},"complexity_factors":["Extremely short document — only 8 substantive lines","Single mechanical requirement referencing an external technical document (Beechcraft SI 1173)","No defined terms section — all language is plain technical aviation terminology","Simple applicability test based solely on aircraft serial number","Single compliance deadline with straightforward calculation (100 hours after fixed date)","No conditional logic, exceptions, or nested provisions","Cross-reference to FAA AD provided only as informational note, not as operative text"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for specific Beechcraft aeroplanes.\n\n**What it does:** It requires owners and operators of certain Beechcraft Model 77 \"Skipper\" aircraft to inspect and fix a problem with the **shoulder harness attach bracket** — the metal fitting that anchors your seatbelt across your shoulder. Some aircraft were built with brackets that don't have enough rivets or proper spacing from the edge of the metal, which could cause the bracket to fail in a crash.\n\n**Who it affects:** Anyone who owns or operates a Beechcraft Model 77 with specific serial numbers (WA-3 through WA-235, plus several others listed — basically most Skippers ever made).\n\n**What you must do:** Follow the instructions in **Beechcraft Service Instruction No. 1173, Revision 1** — a technical manual from the manufacturer that tells mechanics exactly how to inspect and repair the bracket.\n\n**When you must do it:** Within 100 hours of flying time after 30 September 1981. (Yes, this is old — but ADs remain binding until complied with or superseded.)\n\n**Why it matters:** If the bracket fails, your shoulder harness won't hold you in a crash. This amendment expands the original directive to catch more aircraft that might have the same manufacturing defect.\n\n**Key point:** This is **Amendment 1**, meaning it widens the net — the original directive missed some serial numbers that also have the faulty brackets."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-77-7-amdt-1-shoulder-harness-attach-bracket","history":"/api/acts/ad-beech-77-7-amdt-1-shoulder-harness-attach-bracket/history","analysis":"/api/acts/ad-beech-77-7-amdt-1-shoulder-harness-attach-bracket/analysis","conflicts":"/api/acts/ad-beech-77-7-amdt-1-shoulder-harness-attach-bracket/conflicts","importantCases":"/api/acts/ad-beech-77-7-amdt-1-shoulder-harness-attach-bracket/important-cases","documents":"/api/acts/ad-beech-77-7-amdt-1-shoulder-harness-attach-bracket/documents"}}