{"id":"F2020L01122","name":"AD/GC-1/3 Stabilizer Spar Attachment - Inspection","slug":"ad-gc-1-3-stabilizer-spar-attachment-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":113538,"registerId":"commonwealth-F2020L01122-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Swift Museum Foundation GC-1A and GC-1B ","sectionType":"part","heading":"Swift Museum Foundation GC-1A and GC-1B Series Aeroplanes","content":"# Swift Museum Foundation GC-1A and GC-1B Series Aeroplanes\n\n| AD/GC-1/3 | Stabilizer Spar Attachment - Inspection | 18/2020 |\n| --------- | --------------------------------------- | ------- |\n\n| Applicability: | All Swift Museum Foundation GC-1A and GC-1B model aircraft. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | 1. Inspect the horizontal stabilizer front spar attachment to the fuselage bulkhead for looseness. First remove all fairing or interfering items. Support the horizontal stabilizers on the fuselage so that their position cannot change; remove the four AN 3 bolts which attach the front stabilizer spar to the fuselage bulkhead. If there is no deformation or elongation of these bolt holes and if the holes in the stabilizer spar and the fuselage bulkhead are in correct alignment the AN 3 bolts must be reinstalled, torquing them to 25-30 inch-pounds.If there is deformation or elongation of the attach bolt holes, a repair can be accomplished by reaming these 3/16-inch holes to 1/4-inch diameter with the stabilizers firmly blocked in the proper position with the fuselage. The AN 3 bolts, nuts, and washers must be replaced with AN 4 bolts, nuts, and washers, and they must be torqued to 80-90 inch-pounds in reassembling the stabilizer front spar attachment.Replacement of the AN 3 bolts, nuts, and washers with AN 4 bolts, nuts and washers constitutes terminating action for the requirements of this AD.Note: United States of America Federal Aviation Administration (FAA) AD 51-08-03 is the source document for the requirements of this AD. |\n| Compliance: | 1. Unless previously accomplished, within 6 months after the commencement date of this AD and thereafter at each 100 hours’ time in service or every 12 months, whichever occurs first. |\n| | This AD commences on 17 September 2020. |\n| Background: | An audit of the Australian Aircraft Register found that Swift Museum Foundation GC-1A aircraft have been on the register for some time and that requirements equivalent to the applicable FAA ADs have not previously been mandated in Australia for these aircraft. |\n\n| | This AD is issued to mandate requirements equivalent to FAA AD 51-08-03. |\n| --- | ------------------------------------------------------------------------ |\n\n![A drawing of a face\nDescription automatically generated](image.001.jpeg)\n\nPieter van Dijk \nDelegate of the Civil Aviation Safety Authority\n\n25 August 2020","sortOrder":0},{"sectionNumber":"AD/GC-1/3","sectionType":"part","heading":"AD/GC-1/3","content":"## AD/GC-1/3","sortOrder":1},{"sectionNumber":"Stabilizer Spar Attachment - Inspection","sectionType":"part","heading":"Stabilizer Spar Attachment - Inspection","content":"## Stabilizer Spar Attachment - Inspection","sortOrder":2},{"sectionNumber":"18/2020","sectionType":"part","heading":"18/2020","content":"## 18/2020","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD precisely matches its original intent: mandating a specific 1951 US safety inspection for vintage Swift aircraft that were missing from the Australian register. No scope creep — it's a targeted, one-issue directive."},"complexity_factors":["Single, clearly defined mechanical task with step-by-step instructions","Only one defined term ('time in service' — standard aviation term)","No cross-references to other legislation beyond noting the source FAA document","Simple binary decision tree: holes damaged or not damaged","Clear compliance dates and intervals","Terminating action clearly specified (upgrading to AN 4 bolts ends the requirement)"],"plain_english_summary":"This AD mandates inspections of the horizontal stabilizer-to-fuselage connection on Swift Museum Foundation GC-1A/GC-1B aircraft to detect looseness or elongated bolt holes. It requires removing fairings, supporting the tail, removing four bolts to inspect holes, reinstalling same-size bolts torqued correctly if OK, or drilling and fitting larger bolts as a terminating fix.\n\nFirst inspection within six months of September 2020, then every 100 flight hours or 12 months. It prevents possible in‑flight tail separation; CASA is adopting an older FAA safety rule."},"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":true,"description":"This AD brings Australian regulation into alignment with FAA AD 51‑08‑03 by mandating inspections and repairs for all Swift GC‑1A and GC‑1B aircraft on the Australian register. Previously equivalent FAA requirements had not been mandated domestically, so the AD expands mandatory regulatory coverage and imposes recurring maintenance obligations on owners/operators."},"complexity_factors":["Technical precision: specifies bolt sizes (AN3→AN4), hole diameters (3/16\" to 1/4\"), and torque values (25–30 and 80–90 inch‑pounds).","Operational scheduling: recurring compliance at 100 flight hours or 12 months creates ongoing maintenance planning.","Repair method specificity: requires blocking stabilizers in the proper position during reaming, increasing shop skill and fixture needs.","Parts and supply impact: mandates replacement with AN4 bolts/nuts/washers, creating procurement obligations for owners/maintenance providers.","Cross-reference to external instrument: mirrors FAA AD 51‑08‑03, so implementers must track and reconcile both documents.","Regulatory reach: applies to all GC‑1A and GC‑1B on the Australian register, expanding prior domestic coverage."],"plain_english_summary":"This AD requires owners/operators of Swift Museum Foundation GC-1A and GC-1B aeroplanes to inspect the horizontal stabilizer front spar attachment and, if bolt holes are deformed, ream them and replace AN3 bolts with larger AN4 bolts to specified torque values. Inspections must occur within six months and then every 100 flight hours or 12 months. Owners/operators bear inspection and repair costs and must follow the mandated maintenance steps and parts/specifications."}},"importantCases":[],"_links":{"self":"/api/acts/ad-gc-1-3-stabilizer-spar-attachment-inspection","history":"/api/acts/ad-gc-1-3-stabilizer-spar-attachment-inspection/history","analysis":"/api/acts/ad-gc-1-3-stabilizer-spar-attachment-inspection/analysis","conflicts":"/api/acts/ad-gc-1-3-stabilizer-spar-attachment-inspection/conflicts","importantCases":"/api/acts/ad-gc-1-3-stabilizer-spar-attachment-inspection/important-cases","documents":"/api/acts/ad-gc-1-3-stabilizer-spar-attachment-inspection/documents"}}