{"id":"F2006B03806","name":"AD/BEECH 33/39 - Cabin Fresh Air Blower","slug":"ad-beech-33-39-cabin-fresh-air-blower","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43402,"registerId":"commonwealth-F2006B03806-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 33/39 - Cabin Fresh Air Blower","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)  Beechcraft 33 and 35-33 (Debonair/Bonanza) Series Aeroplanes\n\n \n\nAD/BEECH 33/39 Cabin Fresh Air Blower 12/91\n\nApplicability: Model F33A with serial numbers CE-941 through CE-1555.\n\n \n\nModel F33C with serial numbers CJ-156 through CJ-179.\n\n \n\nRequirement: Action in accordance with the Technical Requirements of FAA AD 91-20-08 Amdt 39-8042.\n\n \n\nNote: Beech SB 2380 refers.\n\n \n\nCompliance: As specified in the requirement document with a revised effective date of 12 December 1991 for Australian registered aircraft.\n\n \n\nBackground: Reports have been received of air blower housing attachment failures. This condition could lead to blower impingement on the flight control cables located below the blower. The effective date required by the FAA is extended by approximately one month.\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The Australian directive adopts the FAA AD’s technical requirements unchanged but alters the compliance timing by extending the FAA effective date by approximately one month for Australian-registered aircraft. Applicability and required actions are otherwise taken from the FAA AD (Applicability; Requirement; Compliance; Background)."},"complexity_factors":["Cross-reference to an external technical document (FAA AD 91-20-08) — requires users to obtain and follow another instrument.","Narrow, serial-numbered applicability — requires checking individual aircraft serial numbers.","Technical content is delegated to the FAA AD and a manufacturer service bulletin (Beech SB 2380) rather than set out in full here.","Compliance timing modification (Australian revised effective date) introduces a jurisdictional timing nuance.","Practical complexity for owners arises from expected maintenance work, parts, labour and aircraft downtime, even though the AD text itself is short."],"plain_english_summary":"What this directive does (mechanics)\n\n- Requires owners/operators of certain Beechcraft aeroplanes to carry out the technical actions set out in FAA Airworthiness Directive 91-20-08 (Requirement). (Requirement)\n- Applies only to Model F33A aeroplanes with serial numbers CE-941 through CE-1555, and Model F33C aeroplanes with serial numbers CJ-156 through CJ-179. (Applicability)\n- Sets the compliance timing for Australian-registered aircraft to a revised effective date of 12 December 1991 — the FAA effective date was extended by about one month for Australia. (Compliance; Background)\n- Refers to Beech Service Bulletin 2380 as related information. (Note)\n\nWho it affects\n\n- Aircraft owners and operators of the specified F33A and F33C serial-numbered aeroplanes. (Applicability)\n- Maintenance organisations and technicians who must carry out the technical work required by FAA AD 91-20-08. (Requirement)\n\nWhy it matters (stated safety concern and practical implications)\n\n- The directive responds to reports of air blower housing attachment failures. If the blower housing fails, the blower could impinge on flight control cables located below it. The action required is intended to eliminate or reduce that hazard. (Background)\n\nWho pays, who decides, and what behaviour changes\n\n- Who pays: The directive makes the aircraft owner or operator responsible for implementing the FAA AD’s technical requirements (inspections, repairs or replacements as specified). The text does not list funding or subsidies. (Requirement)\n- Who decides: The Australian instrument directs compliance by reference to the FAA AD and sets an Australian effective date; it therefore operationalises the FAA AD for the listed Australian-registered aircraft. (Requirement; Compliance)\n- Behaviour changes: Owners/operators must arrange and pay for the specified technical actions (inspection/repair/replacement) within the times specified in the FAA AD; maintenance providers will perform the work. (Requirement)\n\nTrade-offs, costs and implementation notes\n\n- Cost and compliance burden: The directive requires technical work defined in another document (FAA AD 91-20-08). That creates an expected direct cost to owners/operators for parts, labour and aircraft downtime. (Requirement)\n- Cross-jurisdiction reference: The Australian directive does not set its own technical steps but adopts the FAA AD; compliance therefore depends on accessing and following that external technical document. (Requirement)\n- Timing change: Australia extended the FAA effective date by approximately one month for Australian-registered aircraft; this shifts the immediate timing of costs and action for affected owners/operators. (Compliance; Background)\n- Service bulletin linkage: The directive refers to Beech SB 2380, which may provide manufacturer-recommended methods or details that interact with the FAA AD’s technical requirements. Operators should consult both documents when planning work. (Note)\n\nImplementation risks and administrative discretion\n\n- Implementation depends on correct interpretation and execution of FAA AD 91-20-08 and related Beech SB 2380 by maintenance personnel; errors or incomplete compliance could leave the hazard unaddressed. (Requirement; Note)\n- The only explicit administrative discretion shown in the text is the revision of the effective date for Australian-registered aircraft; no other exemptions or alternative compliance options are stated in this instrument. (Compliance; Background)\n\nSource citations\n\n- Applicability: lists the exact affected serial numbers. (Applicability)\n- Required action: refers to FAA AD 91-20-08 for the technical requirements. (Requirement)\n- Compliance timing: revised effective date of 12 December 1991 for Australian-registered aircraft. (Compliance)\n- Safety rationale: reports of blower housing attachment failures creating risk to flight control cables. (Background)\n- Related manufacturer material: Beech SB 2380. (Note)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in defined aircraft. It has not expanded beyond its original purpose of mandating inspection/repair of the cabin fresh air blower housing."},"complexity_factors":["Single, specific mechanical issue (blower housing attachment)","Limited applicability: only 2 aircraft models with defined serial number ranges","Short document (under 200 words)","No defined terms section; plain language used throughout","Single cross-reference to FAA AD 91-20-08 and one service bulletin","No nested conditions or exceptions — straightforward compliance requirement"],"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 like a compulsory recall notice for aircraft, but with legal force.\n\n**What it does:** It requires owners and operators of specific Beechcraft aeroplanes (models F33A and F33C with certain serial numbers) to take corrective action on the **cabin fresh air blower**. The blower housing can break loose, and if it does, the spinning fan could hit the flight control cables running underneath — potentially causing loss of control of the aircraft.\n\n**Who must comply:** Anyone operating an Australian-registered Beechcraft F33A (serial numbers CE-941 to CE-1555) or F33C (serial numbers CJ-156 to CJ-179) must follow the technical instructions in the referenced US Federal Aviation Administration (FAA) directive (AD 91-20-08).\n\n**Why it matters:** This is a **safety-critical fix**. The directive prevents a mechanical failure that could interfere with the cables pilots use to steer the plane. The Australian version gives operators about one extra month to comply compared to the US deadline (extending the effective date to 12 December 1991).\n\n**Key reference:** Operators should also consult Beechcraft Service Bulletin 2380 for detailed guidance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-33-39-cabin-fresh-air-blower","history":"/api/acts/ad-beech-33-39-cabin-fresh-air-blower/history","analysis":"/api/acts/ad-beech-33-39-cabin-fresh-air-blower/analysis","conflicts":"/api/acts/ad-beech-33-39-cabin-fresh-air-blower/conflicts","importantCases":"/api/acts/ad-beech-33-39-cabin-fresh-air-blower/important-cases","documents":"/api/acts/ad-beech-33-39-cabin-fresh-air-blower/documents"}}