{"id":"F2006B06872","name":"AD/SD3-60/28 - Horizontal Stabilizer - Rear Spar Web/Boom","slug":"ad-sd3-60-28-horizontal-stabilizer-rear-spar-web-boom","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114752,"registerId":"commonwealth-F2006B06872-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SD3-60/28 - Horizontal Stabilizer - Rear Spar Web/Boom","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/SD3-60/28 Horizontal Stabilizer - Rear Spar Web/Boom 7/88\n\nDM\n\n \n\nApplicability: All models with S/Nos SH3601 to SH3691 and SH3694. Requirement:  Action in accordance with Shorts SB SD360-55-16.\n\nCompliance: Unless already accomplished, prior to 31 July 1988 and thereafter as per Requirement Document until modified in accordance with Shorts SB SD360-55-12.\n\n \n\nBackground:  Testing on a horizontal stabilizer with service usage has shown failure of some rivets connecting the rear spar web to the booms.\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 discrete, time-bound safety directive with a narrow scope (specific aircraft serial numbers, specific structural component). It has not expanded beyond its original purpose of addressing a known structural defect."},"complexity_factors":["Single, specific technical requirement referencing external manufacturer documents","Limited applicability (specific aircraft serial number range)","Clear compliance deadline (31 July 1988)","No nested conditional logic or extensive cross-referencing within the text itself","Relies on external technical documents (Service Bulletins) for actual procedural detail"],"plain_english_summary":"This is an **Airworthiness Directive** (AD) issued by Australia's Civil Aviation Safety Authority (CASA). It is a mandatory safety order for owners and operators of specific **Short SD3-60 series aircraft** (a type of regional turboprop plane).\n\n**What it does:**\n- Requires inspection and repair of the **horizontal stabilizer** (the small wing at the tail of the aircraft that keeps the plane level in flight)\n- Specifically targets the **rear spar web and boom** — structural parts that connect the stabilizer to the fuselage\n- Mandates action because testing found **rivet failures** in this area on aircraft with flight hours\n\n**Who it affects:**\n- Owners and operators of Short SD3-60 aircraft with **serial numbers SH3601 to SH3691 and SH3694**\n\n**What must be done:**\n- Follow the instructions in **Shorts Service Bulletin SD360-55-16** (a technical repair notice from the manufacturer)\n- Complete the work **before 31 July 1988** (if not already done)\n- Continue periodic inspections as specified until a permanent modification (per **Shorts SB SD360-55-12**) is installed\n\n**Why it matters:**\nRivet failures in the horizontal stabilizer could compromise the aircraft's ability to maintain stable flight, posing a serious safety risk. This directive ensures structural integrity before a catastrophic failure occurs."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The AD’s scope is limited to the specific aircraft serial numbers listed and to following the manufacturer’s service bulletin. The instrument does not expand or narrow that scope within the text provided; it mandates the SB action before a specified date and continues obliging operators to follow the Requirement Document until that document is modified by the later Shorts SB SD360-55-12. (Applicability / Requirement / Compliance)"},"complexity_factors":["Reference to external technical documents (Shorts SB SD360-55-16 and SD360-55-12) which contain the operative technical instructions","Serial-number-limited applicability (specific range and an omitted serial), requiring careful fleet identification","A fixed initial compliance deadline plus continuing obligations governed by a separate Requirement Document","Safety-critical, structural nature of the defect (rear spar web to boom rivet failures) requiring qualified maintenance","Operational impact risk (aircraft downtime) and costs are not specified in the AD itself, requiring operators to estimate resource impact","Dependence on the manufacturer’s bulletin for technical detail creates an implementation dependency and potential ambiguity if the SB is updated or unclear"],"plain_english_summary":"This AD requires owners/operators of Short SD3‑60 aeroplanes serial SH3601–SH3691 and SH3694 to carry out the corrective inspection/repair in Shorts Service Bulletin SD360‑55‑16 before 31 July 1988, and to continue to follow the Requirement Document’s maintenance intervals until superseded. It was issued because testing found rivet failures on the horizontal stabilizer rear spar web/boom connection; operators bear the cost and scheduling burden."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sd3-60-28-horizontal-stabilizer-rear-spar-web-boom","history":"/api/acts/ad-sd3-60-28-horizontal-stabilizer-rear-spar-web-boom/history","analysis":"/api/acts/ad-sd3-60-28-horizontal-stabilizer-rear-spar-web-boom/analysis","conflicts":"/api/acts/ad-sd3-60-28-horizontal-stabilizer-rear-spar-web-boom/conflicts","importantCases":"/api/acts/ad-sd3-60-28-horizontal-stabilizer-rear-spar-web-boom/important-cases","documents":"/api/acts/ad-sd3-60-28-horizontal-stabilizer-rear-spar-web-boom/documents"}}