{"id":"F2006B11444","name":"AD/P166/17 - Angle Bar at Fuselage Frame 20 - Inspection and Modification","slug":"ad-p166-17-angle-bar-at-fuselage-frame-20-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57385,"registerId":"commonwealth-F2006B11444-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/P166/17 - Angle Bar at Fuselage Frame 20 - Inspection and 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)  Piaggio P166 Series Aeroplanes\n\n \n\nAD/P166/17 Angle Bar at Fuselage Frame 20 - Inspection\n\nand Modification\n\n\n5/62\n\n \n\nApplicability: S/Nos. prior to 404. Document:  Piaggio SB P166-16. Compliance:  Forthwith.\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\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, single-issue airworthiness directive addressing one specific structural component on one aircraft type. It has not expanded beyond its original purpose of mandating inspection and modification of the angle bar at fuselage frame 20."},"complexity_factors":["Extremely short document — only 8 substantive lines of regulatory text","No defined terms section — all language is plain technical aviation terminology","No cross-references to other legislation beyond the enabling Civil Aviation Regulations 1998","Single, unambiguous compliance requirement ('forthwith') with no conditional exceptions or alternative methods of compliance","Simple applicability test based solely on aircraft serial number","No nested logic or procedural branching — one action applies to all affected aircraft"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires owners or operators of specific aircraft to take immediate action to fix a known safety problem.\n\n**What it does:**\n- **Targets:** Piaggio P166 series aeroplanes (a type of Italian-made twin-engine aircraft used for transport, surveillance, and other purposes)\n- **Affects:** Only those with **serial numbers prior to 404** (earlier production models)\n- **The problem:** A structural issue with an **angle bar** (a metal bracket or reinforcing piece) located at **fuselage frame 20** (a specific point in the aircraft's body structure)\n- **Required action:** Operators must **inspect and modify** this angle bar component\n- **When:** **Forthwith** — meaning immediately, without delay\n\n**Why it matters:**\n- Airworthiness Directives are **legally binding**. Flying an aircraft without complying with an AD is illegal and dangerous.\n- This particular AD addresses a potential structural weakness that could affect the aircraft's safety if left unaddressed.\n- The \"forthwith\" compliance requirement indicates CASA considers this a serious safety issue requiring urgent attention.\n\n**Source document:** The directive references **Piaggio Service Bulletin P166-16** — the manufacturer's official technical notice describing the required inspection and modification procedure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text provided does not indicate any change in scope from a prior instrument. It prescribes inspection and modification for Piaggio P166 series aeroplanes with serial numbers prior to 404, references Piaggio SB P166-16 for technical instructions, and requires compliance forthwith. No statement in the excerpt amends or narrows that applicability or the required action."},"complexity_factors":["Narrow applicability: limited to Piaggio P166 series aircraft with serial numbers prior to 404 (clear, low scope breadth).","Immediate compliance required (\"Forthwith\"), which raises operational urgency but not procedural complexity.","Dependence on an external technical document (Piaggio SB P166-16) for detailed steps creates a need to consult another source to implement the AD.","The AD excerpt contains minimal procedural detail, so implementing parties must interpret and act on the referenced service bulletin—this increases procedural dependency though not legal complexity.","Regulatory enforcement and acceptability of alternative means of compliance are not detailed in the excerpt, requiring reference to broader CASA processes for resolution."],"plain_english_summary":"This airworthiness directive from the Civil Aviation Safety Authority requires owners/operators of Piaggio P.166 aeroplanes with serial numbers prior to 404 to inspect and modify the angle bar at fuselage frame 20 immediately, using the procedures in Piaggio Service Bulletin P166‑16. It affects affected aircraft, their maintenance organisations, and imposes immediate compliance costs and potential downtime on operators, who must obtain and follow the referenced service bulletin."}},"importantCases":[],"_links":{"self":"/api/acts/ad-p166-17-angle-bar-at-fuselage-frame-20-inspection-and-modification","history":"/api/acts/ad-p166-17-angle-bar-at-fuselage-frame-20-inspection-and-modification/history","analysis":"/api/acts/ad-p166-17-angle-bar-at-fuselage-frame-20-inspection-and-modification/analysis","conflicts":"/api/acts/ad-p166-17-angle-bar-at-fuselage-frame-20-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-p166-17-angle-bar-at-fuselage-frame-20-inspection-and-modification/important-cases","documents":"/api/acts/ad-p166-17-angle-bar-at-fuselage-frame-20-inspection-and-modification/documents"}}