{"id":"F2006B10342","name":"AD/HILLER 12/1 - Main Rotor Blade - Inspection","slug":"ad-hiller-12-1-main-rotor-blade-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56098,"registerId":"commonwealth-F2006B10342-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HILLER 12/1 - Main Rotor Blade - Inspection","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)  Hiller UH-12 Series Helicopters\n\n \n\nAD/HILLER 12/1 Main Rotor Blade - Inspection 10/60\n\nApplicability: All models fitted with main rotor blades P/No. 2253-1101-03 with 250 or more hours time in service.\n\n \n\nDocument: 1. Hiller SIL No. 3007; or\n\n \n\n2. FAA AD 60-17-2.\n\n \n\nCompliance: At each daily or overnight inspection after 7 October 1970.\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 safety directive focused solely on inspection of one specific rotor blade part number on one helicopter series. It has not expanded beyond its original narrow technical purpose."},"complexity_factors":["Extremely short document (under 200 words)","Only 4 operative provisions: applicability, document references, compliance timing, and the basic inspection requirement","Single condition (250+ hours time in service) with no nested exceptions","No defined terms section — all language is ordinary aviation terminology","No cross-references to other legislation beyond citing source documents","Linear structure with no conditional branching or alternative compliance paths"],"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). Think of it as a \"recall notice\" for aircraft, but legally binding.\n\n**What it does:** It requires owners and operators of **Hiller UH-12 series helicopters** to inspect their **main rotor blades** (specifically part number 2253-1101-03) every single day or after each overnight stop — but only if those blades have clocked **250 or more flight hours**.\n\n**Who it affects:** Anyone flying or maintaining Hiller UH-12 helicopters with the specified rotor blades.\n\n**Why it matters:** Main rotor blades are literally what keep a helicopter in the air. This AD was triggered by safety concerns (referenced in Hiller Service Information Letter No. 3007 and a US FAA directive) to catch potential failures before they cause a crash. The \"10/60\" in the title indicates it was issued in October 1960, with the compliance deadline set for inspections after 7 October 1970.\n\n**The bottom line:** If you've got these specific blades and they've done 250+ hours, you must check them daily. No exceptions."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The supplied directive sets a specific, limited scope (main rotor blades P/No. 2253-1101-03 with 250+ hours) and prescribes inspection frequency and reference documents. The text contains no amendment history or further expansions, so there is no indication in the supplied material that the scope has been changed from any earlier instrument."},"complexity_factors":["Short, single-issue directive with narrow applicability (specific part number and a 250+ hours threshold). (Applicability)","Mandatory recurring timing requirement (each daily or overnight inspection), increasing operational frequency. (Compliance)","Dependence on external technical documents (Hiller SIL No. 3007 or FAA AD 60-17-2) for procedural detail increases implementation complexity. (Document)","Regulatory enforcement context under Part 39/CASA requires mandatory compliance but the AD delegates technical steps to referenced documents. (header, Document)","Date language: AD header date (10/60) and compliance start date (after 7 October 1970) in the text could create ambiguity for implementers verifying effective timing. (Compliance)"],"plain_english_summary":"What this directive changes mechanically\n\n- It requires regular physical inspections of a specific set of main rotor blades fitted to Hiller UH-12 series helicopters. (Applicability)\n- The inspection procedure to be followed is given by one of two external documents: Hiller Service Instruction Letter (SIL) No. 3007 or FAA AD 60-17-2. (Document)\n- The inspections must be carried out at every daily or overnight inspection after 7 October 1970. (Compliance)\n\nWho is affected and who pays\n\n- Affected parties: operators and maintenance organisations that operate Hiller UH-12 helicopters fitted with main rotor blades part number 2253-1101-03 that have accumulated 250 or more hours time in service. (Applicability)\n- Who pays: the operator or maintenance provider bears the direct cost in labour and any downtime required to perform the inspections and any remedial maintenance found necessary. (Applicability, Compliance)\n\nWhat decisions and behaviours change\n\n- Maintenance staff must include the specified blade inspection in the checklist for each daily or overnight inspection for blades meeting the hour threshold. (Compliance, Applicability)\n- Operators must obtain and follow one of the referenced documents to know the exact inspection steps. (Document)\n\nCompliance mechanics, discretion and enforcement\n\n- The directive is issued under the Civil Aviation Regulations Part 39 framework and appears in the Civil Aviation Safety Authority schedule of airworthiness directives; compliance is mandatory for affected aircraft. (header)\n- The AD delegates technical detail to the referenced documents; maintenance personnel decide how to meet the obligation by following those procedures. (Document)\n\nCosts, incentives and trade-offs (source-grounded)\n\n- Costs: increased inspection labour time and possible aircraft downtime at each daily/overnight inspection once blades exceed 250 hours. (Applicability, Compliance)\n- Incentives: operators may retire or replace blades earlier, adjust maintenance scheduling, or increase inspection diligence to avoid corrective work later. (Applicability, Compliance)\n- Trade-offs: the operator exchanges additional recurring inspection effort for the information gained by those inspections. The directive does not quantify benefits or costs. (Applicability, Compliance)\n\nImplementation risks and dependencies\n\n- Implementing the AD requires access to and reliance on the external documents named (Hiller SIL No. 3007 or FAA AD 60-17-2); those documents determine exact inspection steps and criteria for corrective action. (Document)\n- The text provides a clear applicability rule (part number and 250+ hours) and a clear inspection frequency, but implementers must resolve the practical inspection detail from the referenced material. (Applicability, Compliance)\n\nSource citations\n\n- Applicability: \"All models fitted with main rotor blades P/No. 2253-1101-03 with 250 or more hours time in service.\" (Applicability)\n- Document: \"Hiller SIL No. 3007; or FAA AD 60-17-2.\" (Document)\n- Compliance: \"At each daily or overnight inspection after 7 October 1970.\" (Compliance)\n- Regulatory context: \"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 ... CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES.\" (header)\n\nPlain-language summary end."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hiller-12-1-main-rotor-blade-inspection","history":"/api/acts/ad-hiller-12-1-main-rotor-blade-inspection/history","analysis":"/api/acts/ad-hiller-12-1-main-rotor-blade-inspection/analysis","conflicts":"/api/acts/ad-hiller-12-1-main-rotor-blade-inspection/conflicts","importantCases":"/api/acts/ad-hiller-12-1-main-rotor-blade-inspection/important-cases","documents":"/api/acts/ad-hiller-12-1-main-rotor-blade-inspection/documents"}}