{"id":"F2006B06896","name":"AD/SD3-60/5 Amdt 1 - Fuselage Frame 475 - Modification","slug":"ad-sd3-60-5-amdt-1-fuselage-frame-475-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114776,"registerId":"commonwealth-F2006B06896-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SD3-60/5 Amdt 1 - Fuselage Frame 475 - Modification","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)  Short SD3-60 Series Aeroplanes\n\n \n\nAD/SD3-60/5\n\nAmdt 1\n\n\nFuselage Frame 475 - Modification 4/85\n\n \n\nApplicability: All model SD3-60 with S/Nos SH 3601 to SH 3633. Document:  Shorts SB SD360-53-11 R1.\n\nCompliance: Prior to December 1985.\n\n \n\nBackground: The manufacturer reports difficulty in obtaining MS 21141 blind fasteners. The service bulletin has been re-issued and specifies alternate fasteners. The compliance date is also revised.\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\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, technical amendment to a specific airworthiness directive. It remains tightly scoped to its original purpose: ensuring structural integrity of a specific aircraft component. The amendment merely updates implementation details (fastener specifications and deadline) without expanding the scope to additional aircraft, systems, or operational requirements."},"complexity_factors":["Extremely short document (under 200 words)","Only 4 defined elements: specific aircraft model, serial number range, service bulletin reference, and compliance deadline","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Single straightforward requirement with one simple exception (alternate fasteners permitted)","No conditional logic or nested exceptions"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\nOrders owners and operators of specific **Short SD3-60 aircraft** (a type of regional turboprop plane) to modify a structural part called **\"Fuselage Frame 475\"**.\n\n**Who it affects:**\nAnyone who owns or operates Short SD3-60 aircraft with **serial numbers SH 3601 through SH 3633**.\n\n**Why it matters:**\nThe original modification required specific blind fasteners (a type of rivet used in hard-to-reach places) called **MS 21141**. The manufacturer couldn't get enough of these fasteners, so they updated the instructions to allow **alternative fasteners** that work just as safely. The deadline to complete this work was also pushed back to **before December 1985**.\n\n**In short:** If you fly or maintain one of these 33 specific aircraft, you must follow the updated repair instructions using the new approved fasteners before the deadline."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"The amendment changes the technical means of compliance and the compliance timetable set out in the original AD: the manufacturer reported inability to obtain the originally specified MS 21141 blind fasteners, so the service bulletin was re‑issued to specify alternate fasteners and the AD’s compliance date was revised. Implementers must now follow Shorts SB SD360-53-11 R1 (which specifies the alternate fasteners) and complete the modification prior to December 1985 (Background; Document; Compliance)."},"complexity_factors":["Technical, safety‑critical modification to a structural component (fuselage frame 475) requiring certified maintenance and specific fasteners (Applicability; Document).","Narrow applicability tied to a limited set of serial numbers (SH 3601–SH 3633) — implements a targeted population (Applicability).","Mandatory compliance with an externally referenced service bulletin (Shorts SB SD360-53-11 R1) rather than detailed technical specs in the AD itself — requires access to and reliance on an external document (Document).","Supply‑chain element: original fastener (MS 21141) shortage prompted the amendment; operators must acquire alternate fasteners specified in the re-issued bulletin (Background).","Time‑bound mandatory deadline for completion (Compliance: prior to December 1985) creates operational scheduling constraints and potential aircraft downtime (Compliance).","Limited textual detail in the AD about the alternate fasteners and installation steps — implementers must consult the service bulletin for technical specifics (Document)."],"plain_english_summary":"This amendment makes compliance with Shorts Service Bulletin SD360-53-11 R1 mandatory for Short SD3‑60 aeroplanes SN SH3601–SH3633, requiring a fuselage frame 475 modification to be completed prior to December 1985. It was issued because MS 21141 blind fasteners were unavailable; the re‑issued bulletin specifies alternate fasteners. Owners/operators must obtain the bulletin, perform the work at their cost, and follow the new fastener and installation instructions to remain compliant."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sd3-60-5-amdt-1-fuselage-frame-475-modification","history":"/api/acts/ad-sd3-60-5-amdt-1-fuselage-frame-475-modification/history","analysis":"/api/acts/ad-sd3-60-5-amdt-1-fuselage-frame-475-modification/analysis","conflicts":"/api/acts/ad-sd3-60-5-amdt-1-fuselage-frame-475-modification/conflicts","importantCases":"/api/acts/ad-sd3-60-5-amdt-1-fuselage-frame-475-modification/important-cases","documents":"/api/acts/ad-sd3-60-5-amdt-1-fuselage-frame-475-modification/documents"}}