{"id":"F2006B07525","name":"AD/UH-1/11 - Pillow Block Bolts and Hardware","slug":"ad-uh-1-11-pillow-block-bolts-and-hardware","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50065,"registerId":"commonwealth-F2006B07525-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.","sortOrder":0},{"sectionNumber":"AD/UH-1/11 Pillow Block Bolts and Hardwa","sectionType":"part","heading":"AD/UH-1/11 Pillow Block Bolts and Hardware 8/2000","content":"# AD/UH-1/11 Pillow Block Bolts and Hardware 8/2000\n\nApplicability: Models UH1B, UH1F, and UH1H.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 92-23-01. Compliance: Before further flight after the effective date of this directive, thereafter at each:\n\n    each hub assembly,\n    overhaul,\n    change of a MR hub retention strap, or\n    whenever the bolts are removed for any reason.\n\nThis Airworthiness Directive becomes effective on 10 August 2000.\n\nBackground: This directive follows the detection of cracks in the pillow block bolts on Model 205 and 212 helicopters. Failure of all four bolts will permit main rotor separation.\n\n![Signature of David Alan Villiers Delegate of the Civil Aviation Safety Authority](image.003.png)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 6 July 2000\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 12 July 2000.","sortOrder":1}],"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing a specific mechanical failure mode in specific helicopter models. It does not expand beyond aviation safety into broader operational or regulatory areas."},"complexity_factors":["Very short document (under 300 words)","Only 3 defined applicability criteria (specific helicopter models)","Single requirement referencing external FAA document rather than detailing technical steps","Simple compliance trigger structure (4 straightforward conditions)","No nested exceptions or conditional logic","No cross-references to other Australian legislation beyond enabling regulation (CAR 1998 subreg 39.1(1))"],"plain_english_summary":"This AD requires Australian operators of Bell UH‑1B, UH‑1F and UH‑1H helicopters to follow FAA AD 92‑23‑01 and inspect/maintain main‑rotor “pillow block” bolts. Cracked bolts have led to main‑rotor separation on similar models; mandatory inspections before flight (after 10 Aug 2000) and at recurring maintenance intervals aim to prevent catastrophic failure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive adopts the FAA technical requirements and applies to the specified UH‑1 models; it imposes immediate and recurring inspection/repair obligations consistent with the stated unsafe condition (Applicability; Requirement; Compliance; Background). There is no textual indication the scope was broadened or narrowed from the stated corrective objective."},"complexity_factors":["Direct cross-reference to an external FAA AD (FAA AD 92-23-01) for technical requirements increases dependency on another instrument.","Multiple recurring compliance triggers: before further flight after issue, and thereafter at each hub assembly, overhaul, retention‑strap change, or bolt removal (Compliance).","Immediate safety-critical consequence (main rotor separation if all four bolts fail) concentrates operational urgency (Background).","Narrow applicability limited to UH1B, UH1F, UH1H models reduces population but increases per-unit criticality (Applicability).","Issued under delegated regulatory power (subregulation 39.1(1) of CAR 1998), so administrative discretion at the delegate level is the legal basis.","Operational and maintenance cost burden falls on operators/maintenance organisations who must inspect/repair/replace hardware per the AD (Requirement)."],"plain_english_summary":"**This Airworthiness Directive** requires operators of Bell UH‑1B, UH‑1F and UH‑1H helicopters to carry out the technical actions in FAA AD 92‑23‑01 on pillow‑block bolts and hardware, and to do so before further flight and thereafter at each hub assembly, overhaul, change of a main‑rotor hub retention strap, or whenever those bolts are removed (Requirement; Compliance). CASA issued the AD after cracks were found in pillow‑block bolts; operators pay for inspections/repairs and must follow the delegate's instructions to prevent main‑rotor separation (Background)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-uh-1-11-pillow-block-bolts-and-hardware","history":"/api/acts/ad-uh-1-11-pillow-block-bolts-and-hardware/history","analysis":"/api/acts/ad-uh-1-11-pillow-block-bolts-and-hardware/analysis","conflicts":"/api/acts/ad-uh-1-11-pillow-block-bolts-and-hardware/conflicts","importantCases":"/api/acts/ad-uh-1-11-pillow-block-bolts-and-hardware/important-cases","documents":"/api/acts/ad-uh-1-11-pillow-block-bolts-and-hardware/documents"}}