{"id":"F2006B08534","name":"AD/CH-3/3 - Front Seat Restraint Installation - Modification","slug":"ad-ch-3-3-front-seat-restraint-installation-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51300,"registerId":"commonwealth-F2006B08534-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CH-3/3 - Front Seat Restraint Installation - 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)  Chrislea CH-3 Series Aeroplanes\n\n \n\nAD/CH-3/3 Front Seat Restraint Installation - Modification 9/72\n\nApplicability: All models.\n\n \n\nRequirement: Modify each front seat restraint installation by fitting a safety harness in accordance with a scheme approved by the Secretary.\n\n \n\nNote: Guidelines for installation schemes are outlined in Airworthiness Advisory Circular No. 62 dated March 1972.\n\n \n\nCompliance: Before 1 October 1973.\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":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument itself does not indicate any change from an earlier or original intent. It sets a clear mandatory requirement applicable to all Chrislea CH-3 models to install a safety harness per a scheme approved by the Secretary, with guidance referenced in Airworthiness Advisory Circular No. 62 and a compliance date of 1 October 1973 (Applicability; Requirement; Note; Compliance)."},"complexity_factors":["Single, clear technical requirement (fit safety harness) reduces legal complexity (Requirement).","Applicability to all models simplifies scope but broadens affected population (Applicability).","Approval by the Secretary introduces administrative discretion and an approval process (Requirement).","Reference to an external advisory circular requires cross-reference to technical guidance (Note).","Fixed compliance deadline concentrates implementation burden and scheduling requirements (Compliance)."],"plain_english_summary":"What this instrument does (mechanical change)\n\n- Requires that each front seat restraint installation on Chrislea CH-3 series aeroplanes be modified by fitting a safety harness \"in accordance with a scheme approved by the Secretary.\" (Requirement)\n- Applies to all models of the Chrislea CH-3 series. (Applicability)\n- Sets a deadline for completion of the modification: before 1 October 1973. (Compliance)\n- Points to guidance for acceptable installation schemes in Airworthiness Advisory Circular No. 62 (March 1972). (Note)\n\nWho it affects and who decides\n\n- Affects all owners/operators of Chrislea CH-3 series aeroplanes because the requirement applies to every aircraft of those models. (Applicability; Requirement)\n- The Secretary (a regulatory decision-maker named in the instrument) approves the installation schemes that must be followed. That approval function gives the Secretary discretion over whether a particular harness installation meets the required scheme. (Requirement)\n\nWhy this matters (stated authority and operational effects)\n\n- The instrument imposes a mandatory mechanical change to aircraft equipment (front seat harness installation) and sets a mandatory compliance date. (Requirement; Compliance)\n- It ties acceptable installations to an approved scheme and refers operators to an advisory circular for guidance, creating a two-part conformity test: follow the Secretary’s approved scheme and the referenced advisory guidance. (Requirement; Note)\n\nPractical costs, incentives and trade-offs (mechanics, not judgement)\n\n- Compliance imposes an operational and financial obligation on the parties who own or operate the affected aircraft: they must arrange for the physical installation work, and complete it by the specified date. (Requirement; Compliance)\n- Because approval is required from the Secretary, operators must obtain regulatory sign-off for their installation scheme or use a scheme already approved by the Secretary; that introduces an administrative step and a point of regulatory discretion. (Requirement)\n- The advisory circular provides installation guidelines but the ultimate acceptability depends on meeting the Secretary’s approved scheme; relying solely on the circular does not remove the need for approval. (Note; Requirement)\n\nImplementation risk and compliance burden\n\n- The fixed compliance deadline concentrates the time by which work must be done, which may create scheduling, cost, or logistic pressures for owners/operators. (Compliance)\n- The Secretary’s approval role means there is a single point of regulatory assessment; operators may need to wait for approval or modify proposals to gain approval. (Requirement)\n\nEffects on private choice and markets\n\n- The requirement constrains maintenance and modification choices for owners/operators of the specified aircraft models by mandating a particular safety modification and an approval pathway for installation schemes. (Applicability; Requirement)\n- The instrument does not specify who bears the cost, the method of installation, or whether approved schemes will be published; those details are left to compliance action and the Secretary’s approval process. (Requirement; Note)\n\nRelevant text citations\n\n- Applicability: \"All models.\" (Applicability)\n- Requirement: \"Modify each front seat restraint installation by fitting a safety harness in accordance with a scheme approved by the Secretary.\" (Requirement)\n- Note: \"Guidelines for installation schemes are outlined in Airworthiness Advisory Circular No. 62 dated March 1972.\" (Note)\n- Compliance: \"Before 1 October 1973.\" (Compliance)"},"kimi_summary":{"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This is a discrete, single-purpose safety directive. It has not expanded beyond its original intent of mandating shoulder harness installation in Chrislea CH-3 aircraft."},"complexity_factors":["Extremely short document — only 4 substantive lines","No defined terms section","No cross-references to other legislation (only a non-binding reference to an advisory circular)","Single, unambiguous requirement with clear applicability","No conditional logic, exceptions, or nested provisions","Straightforward compliance deadline"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for a specific type of aircraft.\n\n**What it does:** It requires owners or operators of Chrislea CH-3 series aeroplanes (a British light aircraft from the 1950s-60s) to upgrade the front seat safety belts. Specifically, they must replace or modify the existing front seat restraints by installing proper safety harnesses (shoulder straps, not just lap belts) according to a design approved by the Secretary (the government official responsible for aviation safety at the time).\n\n**Who it affects:** Anyone who owns, operates, or maintains a Chrislea CH-3 series aircraft — all models are covered.\n\n**Why it matters:** Lap belts alone don't prevent upper body injuries in crashes. This directive was issued to prevent pilots and front passengers from being thrown forward or hitting the instrument panel during sudden stops or accidents. The reference to \"Airworthiness Advisory Circular No. 62\" provides technical guidance on how to do the installation properly.\n\n**The deadline:** The work had to be completed before 1 October 1973 (this is a historical directive from 1972)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ch-3-3-front-seat-restraint-installation-modification","history":"/api/acts/ad-ch-3-3-front-seat-restraint-installation-modification/history","analysis":"/api/acts/ad-ch-3-3-front-seat-restraint-installation-modification/analysis","conflicts":"/api/acts/ad-ch-3-3-front-seat-restraint-installation-modification/conflicts","importantCases":"/api/acts/ad-ch-3-3-front-seat-restraint-installation-modification/important-cases","documents":"/api/acts/ad-ch-3-3-front-seat-restraint-installation-modification/documents"}}