{"id":"F2006B10402","name":"AD/HS 125/123 Amdt 1 - Wing Top Skin Panel","slug":"ad-hs-125-123-amdt-1-wing-top-skin-panel","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116067,"registerId":"commonwealth-F2006B10402-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HS 125/123 Amdt 1 - Wing Top Skin Panel","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)  British Aerospace BAe 125 Series Aeroplanes\n\n \n\nAD/HS 125/123\n\nAmdt 1\n\n\nWing Top Skin Panel 6/93\n\n \n\nApplicability: Model 125 aircraft up to and including Series 700A and 700B.\n\n \n\nRequirement: Action in accordance with British Aerospace Mandatory Service Bulletin 57-73 Revision 1.\n\n \n\nCompliance: Unless already accomplished, prior to 31 August 1993.\n\n \n\nBackground: Reports of wing top skin corrosion in the area beneath the boundary layer fence.\n\nAmendment 1 is issued in response to a revision of the Requirement Document which extends applicability to include 700 A and B Series aircraft.\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":true,"description":"The original AD (issued June 1993) was amended to expand applicability from earlier BAe 125 models to also include Series 700A and 700B aircraft. This represents a modest expansion of scope to cover additional aircraft variants affected by the same corrosion issue."},"complexity_factors":["Very short document (approximately 150 words)","Only 4 substantive paragraphs (Applicability, Requirement, Compliance, Background)","No defined terms section","No cross-references to other legislation","Single amendment with straightforward purpose (expanding aircraft model coverage)","Relies entirely on external technical document (Service Bulletin 57-73) for actual implementation details"],"plain_english_summary":"This is an **Airworthiness Directive** (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nOrders owners and operators of certain British Aerospace BAe 125 model aircraft to inspect and fix a corrosion problem in the wing top skin panel (the metal surface on top of the wing), specifically in the area beneath the \"boundary layer fence\" (a small aerodynamic device on the wing).\n\n**Who must follow it:**\nAnyone who owns or operates a BAe 125 aircraft up to and including Series 700A and 700B models.\n\n**What action is required:**\nFollow the instructions in British Aerospace Mandatory Service Bulletin 57-73 Revision 1 (a technical repair notice from the manufacturer).\n\n**When it had to be done:**\nBefore 31 August 1993 (unless already completed).\n\n**Why it matters:**\nCorrosion in wing structures can weaken the aircraft and potentially lead to structural failure. This AD was issued after reports of corrosion were received. Amendment 1 expanded the original directive to cover additional aircraft models (700A and 700B series) that weren't included in the first version."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment 1 broadened the directive’s scope by extending applicability to include Series 700A and 700B aircraft that were not covered in the original text. The AD therefore applies to a larger set of Model 125 aircraft and obliges their operators to comply with the cited service bulletin. (Amendment 1; Applicability)"},"complexity_factors":["Narrow, model-specific applicability limited to BAe 125 Model 125 up to and including Series 700A and 700B (Applicability)","Reliance on an external technical document (British Aerospace Mandatory Service Bulletin 57-73 Revision 1) for all technical detail (Requirement)","Fixed compliance deadline creates a time-constrained implementation requirement (Compliance)","The AD itself provides no technical steps, only a mandatory reference, so operators must obtain and follow the manufacturer document (Requirement)","Amendment changes scope by adding additional series, so operators must track updates to applicability (Amendment 1)","Issued under Civil Aviation Regulations Part 39, making it a regulatory airworthiness obligation rather than guidance (header)"],"plain_english_summary":"Owners/operators of BAe 125 aeroplanes (Model 125 up to and including Series 700A and 700B) must carry out the inspections/repairs in British Aerospace Mandatory Service Bulletin 57‑73 Rev 1 by 31 August 1993 to address reported corrosion on the wing top skin beneath the boundary‑layer fence. The directive, issued under CAR Part 39, makes the manufacturer’s bulletin mandatory, imposes direct costs and downtime on operators, and broadens applicability to include Series 700A/700B."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-123-amdt-1-wing-top-skin-panel","history":"/api/acts/ad-hs-125-123-amdt-1-wing-top-skin-panel/history","analysis":"/api/acts/ad-hs-125-123-amdt-1-wing-top-skin-panel/analysis","conflicts":"/api/acts/ad-hs-125-123-amdt-1-wing-top-skin-panel/conflicts","importantCases":"/api/acts/ad-hs-125-123-amdt-1-wing-top-skin-panel/important-cases","documents":"/api/acts/ad-hs-125-123-amdt-1-wing-top-skin-panel/documents"}}