{"id":"F2006B04330","name":"AD/BELL 204/27 Amdt 1 - External Cargo Suspension Kit - Load Restriction and Modification","slug":"ad-bell-204-27-amdt-1-external-cargo-suspension-kit-load-restriction-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44145,"registerId":"commonwealth-F2006B04330-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 204/27 Amdt 1 - External Cargo Suspension Kit - Load Restriction and Modification","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)  Bell Helicopter Textron 204 Series Helicopters\n\n \n\nAD/BELL 204/27\n\nAmdt 1\n\n\nExternal Cargo Suspension Kit - Load NK Restriction and Modification\n\n \n\nApplicability: All model 204B with External cargo suspension kit P/N 204-706-106-1.\n\n \n\nRequirement: 1. Restrict load on external cargo hook in accordance with Bell SB No. 204-78-1 until modified in accordance with Bell SB No. 204-78-4.\n\n \n\n2. Modify external cargo suspension kit P/N 204-706-104-1 in accordance with Bell SB No. 204-78-4.\n\n \n\nCompliance: 1. On any flight utilising the external cargo hook.\n\n \n\n2. Before 1 September 1978.\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":{"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"The instrument’s stated applicability and its mandatory modification requirement reference different part numbers (Applicability: P/N 204-706-106-1; Requirement 2: P/N 204-706-104-1). This inconsistency changes the effective scope compared with a straightforward statement that both the load restriction and the modification apply to the same kit: as written it is unclear whether only kits matching 204-706-106-1 are covered, or whether 204-706-104-1 kits are also captured. The difference creates a practical change from an unambiguous scope (single kit type) because operators and maintainers must seek external clarification to determine which aircraft/kits are covered and therefore which actions are required."},"complexity_factors":["Reliance on external documents (Bell SB No. 204-78-1 and 204-78-4) for the substantive technical content (load limits and modification procedure). (Requirement 1–2)","Inconsistency in part numbers: Applicability cites kit P/N 204-706-106-1, while Requirement 2 directs modification of P/N 204-706-104-1; this creates scope ambiguity that requires external clarification. (Applicability; Requirement 2)","Immediate operational obligation that applies to every flight using the external cargo hook, creating continuous compliance monitoring needs for operators. (Compliance 1)","A firm, date-certain retrofit deadline for the modification imposes scheduling and logistical burdens (parts, labour, downtime). (Compliance 2)","Technical nature of the mandated modification requires qualified maintenance/engineering resources to interpret and implement the SB. (Requirement 2)","Lack of specified enforcement, acceptable evidence of compliance, or alternative compliance pathways increases practical uncertainty for operators and regulators. (Instrument silence)","Narrow applicability (specific helicopter model and kit) concentrates the rule’s effects but increases the need to correctly identify affected aircraft. (Applicability)"],"plain_english_summary":"Summary\n\n- What this instrument does, mechanically: It tells operators of certain Bell 204B helicopters to limit the weight carried on the external cargo hook immediately and then to carry out a specific physical modification to the external cargo suspension kit. The immediate action is a load restriction set out in Bell Service Bulletin (SB) No. 204-78-1. The permanent action is a modification of the external cargo suspension kit according to Bell SB No. 204-78-4 (Requirement 1–2). The document identifies applicability to “all model 204B with External cargo suspension kit P/N 204-706-106-1” (Applicability), and it separately requires modification of a kit identified as P/N 204-706-104-1 (Requirement 2), creating an ambiguity in the part-numbered kits referenced.\n\n- Who is affected: Operators and owners of Bell 204B helicopters that have the specified external cargo suspension kit installed (Applicability). Those operators must follow the load restriction when they use the external cargo hook (Compliance 1) and must perform the required kit modification by the stated deadline (Compliance 2).\n\n- When and how actions must be taken: The load restriction must be observed on any flight that uses the external cargo hook (Compliance 1). The modification of the external cargo suspension kit must be completed before 1 September 1978 (Compliance 2). The exact load limits and the detailed modification steps are not written into this instrument; they are set out in the referenced Bell service bulletins (Bell SB No. 204-78-1 and Bell SB No. 204-78-4) (Requirement 1–2).\n\n- Who pays and who decides: Operators bear the direct costs. They must implement the load restriction in operation (which can reduce payload per flight) and pay for parts, labour and aircraft downtime to carry out the modification specified by Bell SB No. 204-78-4 (Requirement 2, Compliance 1–2). The instrument delegates technical detail to the manufacturer’s service bulletins, so the specific load limit and modification procedure are decided by those SBs (Requirement 1–2).\n\n- Compliance burden and discretion: The instrument sets mandatory obligations rather than discretionary options: the load restriction applies on every flight using the external cargo hook (Compliance 1) and the kit must be modified by the deadline (Compliance 2). The text does not create or record any alternative compliance methods, exceptions, or an approving authority within the instrument itself. Proof of compliance, acceptable evidence, or enforcement procedures are not specified in the text provided.\n\n- Incentives, trade-offs and likely behavioural effects (mechanisms, not judgments): Operators face an immediate operational constraint (reduced allowable external cargo on affected flights) until the modification is completed (Requirement 1, Compliance 1). That raises operating costs per unit of payload (fewer kilos moved per sortie) and a one-off retrofit cost and downtime to install the modification (Requirement 2, Compliance 2). These costs incentivise prompt retrofit where operators rely on external sling loads frequently; they also incentivise avoidance of external-load flights until the modification is done. The safety objective is expressed through mandatory engineering action (Requirement 1–2), but the instrument achieves that by shifting load-limiting and technical detail to the manufacturer SBs, so compliance depends on access to parts, technical capability and adherence to the SB procedures.\n\n- Concentration of benefits and costs: The safety or equipment-specific benefits (reduced risk associated with the kit) are concentrated on operators, crew and third parties exposed to a given helicopter’s external loads. Costs are concentrated on operators who have the affected kit and use external loads, which must either operate with restricted loads or pay for the modification (Applicability, Requirement 1–2).\n\n- Ambiguity and practical risk in the text: The instrument lists the applicable kit as P/N 204-706-106-1 (Applicability) but requires modification of P/N 204-706-104-1 (Requirement 2). That inconsistency is material because it creates uncertainty about which specific kits must be modified; the instrument itself does not resolve that ambiguity. The instrument also relies on external service bulletins for the specific load limits and the modification procedure, so a user must consult those SBs to know the technical steps and numerical limits (Requirement 1–2).\n\nSource citations (from the instrument): Applicability; Requirement 1–2; Compliance 1–2."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, targeted safety directive addressing a specific mechanical defect in a specific helicopter model. It has not expanded beyond its original purpose of ensuring external cargo hook safety."},"complexity_factors":["Very short document (under 200 words)","Only 2 substantive requirements with clear sequential logic","Single defined part number (P/N 204-706-106-1)","References to external technical documents (Bell service bulletins) rather than internal cross-references","Simple binary applicability (all model 204B with specific kit)","No nested exceptions, conditional clauses, or interpretive provisions"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific helicopters.\n\n**What it does:**\n- Applies to **Bell 204B helicopters** that have a particular external cargo hook kit installed (part number 204-706-106-1)\n- Requires **two actions** to prevent the cargo hook from failing:\n  1. **Immediate restriction**: Until the helicopter is modified, operators must limit how much weight they can carry on the external hook, following Bell's safety bulletin 204-78-1\n  2. **Permanent fix**: The cargo suspension kit must be modified according to Bell's service bulletin 204-78-4\n\n**Who it affects:**\n- Owners and operators of Bell 204B helicopters with this specific cargo hook equipment\n- Pilots flying these helicopters with external loads\n\n**Why it matters:**\nThe external cargo hook could fail under certain loads, creating a serious safety risk. This directive forces operators to either restrict operations immediately or complete a mandatory modification by **1 September 1978** to ensure the hook can safely carry its rated load.\n\n**Key deadlines:**\n- Load restrictions apply **immediately** on any flight using the hook\n- The modification must be completed **before 1 September 1978**"}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-204-27-amdt-1-external-cargo-suspension-kit-load-restriction-and-modification","history":"/api/acts/ad-bell-204-27-amdt-1-external-cargo-suspension-kit-load-restriction-and-modification/history","analysis":"/api/acts/ad-bell-204-27-amdt-1-external-cargo-suspension-kit-load-restriction-and-modification/analysis","conflicts":"/api/acts/ad-bell-204-27-amdt-1-external-cargo-suspension-kit-load-restriction-and-modification/conflicts","importantCases":"/api/acts/ad-bell-204-27-amdt-1-external-cargo-suspension-kit-load-restriction-and-modification/important-cases","documents":"/api/acts/ad-bell-204-27-amdt-1-external-cargo-suspension-kit-load-restriction-and-modification/documents"}}