{"id":"F2006B07900","name":"Airworthiness Directives 2004 - Revocation and Remaking - Hiller UH-12 Series Helicopters","slug":"airworthiness-directives-2004-revocation-and-remaking-hiller-uh-12-series-helicopters","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50917,"registerId":"commonwealth-F2006B07900-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"Airworthiness Directives 2004 - Revocation and Remaking - Hiller UH-12 Series Helicopters","content":"Airworthiness Directives 2004\n\nI, DAVID ALAN VILLIERS, delegate of the Civil Aviation Safety\n\nAuthority, acting under subregulation 39.001 (1) of the Civil\n\nAviation Safety Regulations 1998:\n\n(a) revoke the Airworthiness Directives mentioned in\n\nSchedule 1; and\n\n(b) make, as separate instruments, each Airworthiness\n\nDirective mentioned in Schedule 1 and attached.\n\n![](image.001.png)\n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority\n\n20 December 2004\n\nNote: Each attached Airworthiness Directive is being re-made in exactly the\n\nsame form as appears in the latest published edition of the Directive.\n\n  \nSchedule 1 Revocation and Remaking of\n\nAirworthiness Directives\n\nHiller UH-12 Series Helicopters\n\nAD Name AD Number\n\nMain Rotor Blade - Inspection AD/HILLER 12/1\n\nMain Rotor Blade Spar - Inspection AD/HILLER 12/2\n\nTail Rotor Blade Assembly - Provision of Vent Hole AD/HILLER 12/3\n\nMain Transmission - Inspection - CANCELLED AD/HILLER 12/4\n\nMain Rotor Transmission Lube System - Modification - CANCELLED AD/HILLER 12/5 Amdt 2\n\nSuperseded by AD/HILLER 12/11 AD/HILLER 12/6\n\nWobble Plate Screws - Replacement - CANCELLED AD/HILLER 12/7 Amdt 1\n\nMain Rotor Blade Fork AD/HILLER 12/8 Amdt 3\n\nHorizontal Stabiliser Spar - Inspection AD/HILLER 12/9 Amdt 1\n\nMain Rotor Blades - Inspection and Modification AD/HILLER 12/10\n\nTail Rotor Blades - Replacement - CANCELLED AD/HILLER 12/11\n\nMain Rotor Blades - Inspection AD/HILLER 12/12 Amdt 2\n\nTransmission Gear - Inspection AD/HILLER 12/13 Amdt 2\n\nMain Rotor Blade Attach Pin Nut - Modification - CANCELLED AD/HILLER 12/14\n\nMercury Clutch Sideplates - Inspection - CANCELLED AD/HILLER 12/15\n\nCyclic Pitch Control Bracket Attach Bolts and Inserts - Inspection and AD/HILLER 12/16\n\nControl Rotor Blade Assemblies AD/HILLER 12/17 Amdt 4\n\nRetirement Life - Critical Components AD/HILLER 12/18 Amdt 6\n\nMain Rotor Blades - Inspection AD/HILLER 12/19\n\nMercury Clutch - Operational Limitations - CANCELLED AD/HILLER 12/20\n\nMain Rotor Drag Strut - Inspection - CANCELLED AD/HILLER 12/21\n\nMain Rotor Hub AD/HILLER 12/22 Amdt 3\n\nMain Rotor Blade, Anti Node Weight Retention - Inspection AD/HILLER 12/23 Amdt 1\n\nMain Rotor Blade Doubler & Honeycomb Areas AD/HILLER 12/24 Amdt 4\n\nControl Rod End Bearings - Inspection - CANCELLED AD/HILLER 12/25\n\nRotor Tachometer Generator - Replacement AD/HILLER 12/26\n\nOuter Gimbal Forward Attach Fitting - Inspection AD/HILLER 12/27 Amdt 2\n\nMain Rotor Blade Anti-Node Bar - Inspection AD/HILLER 12/28\n\nMain Drive Torsion Coupling - Inspection and Replacement AD/HILLER 12/29 Amdt 4\n\n  \nMain Rotor Assembly AD/HILLER 12/30 Amdt 2\n\nInspection of Lower Gearcase Oil Jets - Soloy Gas Turbine Conversion - AD/HILLER 12/31\n\nTail Rotor Control Balance Cable - Inspection - CANCELLED AD/HILLER 12/32\n\nTail Rotor Blade P/N 55073 - Inspection AD/HILLER 12/33\n\nMain Transmission Oil Filter AD/HILLER 12/34 Amdt 1\n\nMercury Clutch Attach Bolts and Washers - Replacement - CANCELLED AD/HILLER 12/35 Amdt 1\n\nMain Drive Torsion Coupling P/N 21047-15 - Inspection of Lower Plate AD/HILLER 12/36 Amdt 1\n\nSoloy Conversion: Power Turbine Governor Control System - Modification AD/HILLER 12/37\n\nEngine Mount Clevises AD/HILLER 12/38\n\nConsolidation of Early Airworthiness Directives AD/HILLER 12/39\n\nMain Rotor Assembly Drag Strut and T-T Bar Pin AD/HILLER 12/40 Amdt 2\n\nTail Rotor Blades AD/HILLER 12/41\n\nMain Rotor Mast AD/HILLER 12/42\n\nControl System Linkage AD/HILLER 12/43","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"This instrument does not change the substantive scope of regulation. It revokes and re-makes listed Airworthiness Directives in the same form as their latest published editions (instrument text). Therefore the safety requirements and compliance obligations set out in those ADs remain what they were before this instrument. The measure alters legal drafting and instrument status (administrative form and references) but does not expand or narrow the set of technical obligations imposed by the ADs themselves."},"complexity_factors":["Single operative power used: subregulation 39.001(1) of the Civil Aviation Safety Regulations 1998","Schedule lists 43 AD entries (AD/HILLER 12/1 to AD/HILLER 12/43), increasing administrative bookkeeping","Several entries are marked CANCELLED or AMDT (amendment), requiring attention to current operative status of each AD","No definitions section, no nested conditional logic, and the instrument re-makes ADs in the same form (no substantive change introduced)","Low cross-referencing complexity beyond the AD numbers themselves"],"plain_english_summary":"**What this instrument does (mechanically)\n\n- This instrument revokes a list of existing Airworthiness Directives (ADs) that apply to Hiller UH-12 series helicopters and re-issues each of those ADs as separate legal instruments, in the same form as the latest published editions.  The power used is subregulation 39.001(1) of the Civil Aviation Safety Regulations 1998. (See Schedule 1.)\n\n**Who it affects\n\n- Owners and operators of Hiller UH-12 series helicopters, and the maintenance organisations and engineers who perform mandatory work under those ADs.\n\n**Why it matters (official claim and practical effect)\n\n- The instrument’s stated effect is administrative: to revoke the previously listed ADs and re-make them individually so each is a separate instrument. The explanatory note says each re-made AD is “in exactly the same form” as the latest published edition. That means, on its face, no substantive change to the safety requirements is being imposed by this instrument itself.\n\n**Practical consequences, costs and incentives\n\n- Who pays: helicopter owners/operators pay any costs required by the ADs (inspections, parts, labour, modifications). The instrument does not alter those obligations; it merely re-issues the ADs as separate instruments (Schedule 1).  \n- Who decides: the Civil Aviation Safety Authority (CASA), acting through the named delegate, exercises the power to revoke and re-make ADs under subregulation 39.001(1).  \n- Behaviour change required: operators must continue to comply with each AD that remains in force. If an AD in the list was already marked \"CANCELLED\", that indicates the subject AD is not currently operative (Schedule 1). Re-making ADs in the same form should not change compliance steps, but may require operators to note the new instrument references for record-keeping and regulatory tracking.\n\n**Trade-offs, risks and implementation considerations\n\n- Administrative clarification vs paperwork cost: The change appears intended to tidy up legal instruments (making each AD a separate, standalone instrument). That reduces ambiguity about the legal status of each AD, but it creates a modest administrative task for operators and regulators to update records and references.  \n- Compliance burden: Because the text of each AD is re-made unchanged, there is no immediate increase in technical compliance burden imposed by this instrument itself. Any ongoing costs remain those attached to the substantive ADs (inspections, replacements, life limits).  \n- Concentrated benefits and diffuse costs: If the ADs require inspections or parts, maintenance providers and parts suppliers gain concentrated work; the costs are spread across the smaller population of UH-12 operators. The instrument does not create new commercial preferences or exceptions.  \n- Discretion and implementation risk: The delegate uses an existing regulatory power to re-issue ADs. There is limited room in this instrument for discretionary change because the ADs are stated to be re-made in the same form; nevertheless, future administrative errors (mis‑labelling or omission) could create short-term uncertainty about which instrument is operative.  \n- Effect on market competition and private choice: The instrument preserves the existing mandatory safety rules that affect operational costs and availability of aircraft. It does not change ownership rights or remove contractual freedom beyond the obligations already contained in the ADs themselves.\n\n**Source citations and mechanics\n\n- Legal power used: subregulation 39.001(1) of the Civil Aviation Safety Regulations 1998 (instrument text).  \n- Operative action: Schedule 1 lists the ADs being revoked and re-made (AD/HILLER 12/1 through AD/HILLER 12/43, with several entries marked CANCELLED or AMDT). The instrument states each attached AD is being re-made in the same form as the latest published edition.\n\nSummary conclusion (brief): This instrument is administrative housekeeping: it re-issues a set of existing Hiller UH-12 ADs as separate instruments without changing their substantive requirements. The principal practical effects are continued enforcement of those ADs and a small record-keeping/update task for operators and regulators.\n"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a pure administrative consolidation. The instrument explicitly states it is re-making the directives 'in exactly the same form' as the latest published editions. The scope remains precisely limited to Hiller UH-12 series helicopters and the existing safety requirements for that aircraft type."},"complexity_factors":["Simple, single-purpose instrument with clear structure (revocation + remaking)","No defined terms section — relies on external understanding of 'Airworthiness Directive'","Minimal conditional logic — straightforward list format in Schedule 1","Cross-references limited to Civil Aviation Safety Regulations 1998 (subregulation 39.001(1)) and the attached schedules","43 items in Schedule 1 but presented as simple table with status indicators (CANCELLED, Amdt numbers)","No nested exceptions or complex operational rules in the instrument itself (substantive requirements contained in attached ADs not reproduced here)"],"plain_english_summary":"This CASA order cancels all existing Airworthiness Directives for Hiller UH‑12 helicopters and re‑issues them as 43 separate, standalone legal instruments. It’s an administrative tidy‑up: the content and mandatory safety requirements remain unchanged. Owners, operators and maintenance engineers of Hiller UH‑12s retain the same compliance obligations; some previously inactive directives are formally removed."}},"importantCases":[],"_links":{"self":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-hiller-uh-12-series-helicopters","history":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-hiller-uh-12-series-helicopters/history","analysis":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-hiller-uh-12-series-helicopters/analysis","conflicts":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-hiller-uh-12-series-helicopters/conflicts","importantCases":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-hiller-uh-12-series-helicopters/important-cases","documents":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-hiller-uh-12-series-helicopters/documents"}}