{"id":"F2006B07134","name":"AD/STRIKEMASTER/2 - Control Column Cracking","slug":"ad-strikemaster-2-control-column-cracking","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48959,"registerId":"commonwealth-F2006B07134-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/STRIKEMASTER/2 - Control Column Cracking","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nBAe (BAC 167) Strikemaster Series Aeroplanes\n\nAD/STRIKEMASTER/2 Control Column Cracking 12/96 DM\n\nApplicability: BAe BAC 167 Strikemaster all Mks.\n\nRequirement: 1. Inspect the control column in accordance with BAe CSTM/SM/156.\n\n2. Inspect by NDI, the control column lugs for cracks in accordance with BAe CSI/STRIKEMASTER/51.\n\nNote: UK CAA Mandatory Permit Directive 1995-108 refers.\n\nCompliance: 1. Unless already accomplished, before further flight after 25 September 1996.\n\n2. Within 150 hours time in service or 28 days after 25 September 1996, whichever occurs last, after the initial inspection in accordance with Requirement 1; thereafter at intervals not exceeding 150 hours time in service.\n\nBackground: A case has occurred where the upper part of the Post Mod 1759 control column has cracked at the aft lug, which forms part of the column top to base pivot point. As a result, permit holders are required to assure the integrity of the control column structure through ensuring that Requirement 1. has been carried out, and continuing to inspect thereafter.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope aligns with the instrument's stated purpose: to ensure control-column integrity after a detected crack. It applies to all Strikemaster marks and imposes initial and recurring inspections per BAe procedures; no expansion or narrowing of applicability is indicated beyond those directives."},"complexity_factors":["Technical inspection methods required: visual inspection per BAe CSTM/SM/156 and non-destructive inspection (NDI) per BAe CSI/STRIKEMASTER/51 (Requirement 1 & 2).","Multiple timing rules: immediate visual check deadline and an NDI deadline expressed as '150 hours or 28 days, whichever occurs last', plus recurring 150‑hour intervals (Compliance).","Document cross-references: relies on BAe maintenance/inspection documents and notes UK CAA Mandatory Permit Directive 1995-108 (Requirement & Note).","Applicability is broad: applies to all Marks of the BAe BAC 167 Strikemaster (Applicability), so many operators may be affected.","Operational impact: inspections may cause aircraft downtime and create routine maintenance scheduling and cost for permit‑holders (implicit in Compliance and Background)."],"plain_english_summary":"Requires owners and permit-holders of BAe (BAC 167) Strikemaster aircraft to inspect the control column for cracks using BAe-specified procedures, including a non-destructive inspection of the column lugs. Initial and recurring inspection deadlines are specified (visual check before further flight after 25 Sep 1996; NDI within 150 hours or 28 days and every 150 hours thereafter). It matters because a crack was found at a pivotal lug; the directive places inspection and maintenance costs and responsibilities on operators to verify structural integrity."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted airworthiness directive addressing a specific structural defect in a single aircraft type. It maintains narrow, original scope — safety-critical inspection requirements following a reported failure."},"complexity_factors":["Single, specific aircraft type (BAe BAC 167 Strikemaster)","Only 2 technical requirements with clear sequential ordering","Simple compliance timeline with binary condition (already accomplished vs. deadline)","Minimal cross-referencing (2 external manufacturer documents, 1 UK reference)","No defined terms section or interpretation provisions","Single background scenario explaining the safety risk","Straightforward conditional logic (whichever occurs last)"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of BAe BAC 167 Strikemaster aircraft in Australia to inspect the control column for cracks and perform a follow-up non‑destructive inspection of the column lugs within the specified short timeframe, then repeat NDI checks every 150 flight hours. It responds to a cracked aft lug—a critical pivot whose failure could cause loss of control—so compliance is mandatory to ensure safety."}},"importantCases":[],"_links":{"self":"/api/acts/ad-strikemaster-2-control-column-cracking","history":"/api/acts/ad-strikemaster-2-control-column-cracking/history","analysis":"/api/acts/ad-strikemaster-2-control-column-cracking/analysis","conflicts":"/api/acts/ad-strikemaster-2-control-column-cracking/conflicts","importantCases":"/api/acts/ad-strikemaster-2-control-column-cracking/important-cases","documents":"/api/acts/ad-strikemaster-2-control-column-cracking/documents"}}