{"id":"F2006B02482","name":"AD/AS 355/28 Amdt 2 - Installation of Automatic Relighting System","slug":"ad-as-355-28-amdt-2-installation-of-automatic-relighting-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41738,"registerId":"commonwealth-F2006B02482-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AS 355/28 Amdt 2 - Installation of Automatic Relighting System","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nEurocopter AS 355 (Twin Ecureuil) Series Helicopters\n\nAD/AS 355/28\n\nAmdt 2\n\n  \nInstallation of Automatic Relighting System 4/88\n\nDM\n\nApplicability: All model AS 355 E, F, F1 and F2 Helicopters.\n\nRequirement: Install the automatic relighting system (for Allison 250 C20F engine) in accordance with the mandatory requirement of Aerospatiale SB 01.18 Rev 2 and accomplishment instructions detailed in Aerospatiale SB 80-02 Rev 2 or other equivalent system acceptable to the Secretary.\n\nNote: DGAC Bureau Veritas AD 86-153-031 (B) R4 Part B refers.\n\nCompliance: For helicopters in IFR and VFR operations prior to further flight after 31 March 1988.\n\nNote 1: The operating limitations detailed in AD 86-153-031 (B) R4 Part A (a) and (b), now incorporated in the Australian Flight Manual, are cancelled on completion of the automatic relight system installation.\n\nNote 2: Compliance with the previous issue of this Directive does NOT satisfy Compliance with this Amendment 2.\n\nBackground: Several cases of single and two cases of double-engined flameout have been reported one of which resulted in a fatal accident. These incidents occurred in IMC and VMC but always in high humidity with OAT near zero degrees Celsius. Country of Origin AD 86-153-031 (B) R2 publishes the mandatory requirement to embody an automatic relight system for these a/c in both IFR and VFR operations. This Directive is issued to ensure an automatic relight capability prior to the onset of the 1988 Australian winter when conditions conducive to engine flame-out are most likely to be experienced.\n\nThis Directive is amended to reflect Rev 2 to SBs 01.18 and 80.02 and to reference\n\nD.G.A.C. Bureau Veritas AD 86-153-031 (B) Rev 4 which incorporate complimentary modifications 350A07-1910 and 1920 to prevent inadvertent operation of the system.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This Amendment updates and tightens the technical requirements of an existing airworthiness directive but does not expand the Directive beyond its original safety purpose (mandating automatic relight capability for the specified helicopters). The amendment requires compliance with later Service Bulletin revisions, adds referenced modifications to prevent inadvertent system operation, and cancels certain operating limitations once the retrofit is installed. Those are technical refinements rather than a material broadening of the Directive’s scope."},"complexity_factors":["Short, single-subject Airworthiness Directive focused on retrofit of a single system","Applicability limited to 4 specific aircraft model variants and one engine type (Allison 250 C20F)","Cross-references to multiple external technical documents: Aerospatiale SB 01.18 Rev 2, SB 80-02 Rev 2, and DGAC/Bureau Veritas AD 86-153-031 (R4)","Regulatory discretion to accept ‘‘equivalent’’ systems introduces administrative conditionality","Clear compliance deadline (one conditional provision: IFR and VFR operations must comply prior to further flight after 31 March 1988)","Note that prior compliance with earlier Directive issues is explicitly invalidated, creating a rework obligation"],"plain_english_summary":"**What this directive does (mechanically)**\n\n- Requires installation of an automatic engine relighting system for the Allison 250 C20F engines fitted to Eurocopter AS 355 E, F, F1 and F2 helicopters. (See the Requirement.)\n- Insists that the installation follow the mandatory instructions in Aerospatiale Service Bulletin (SB) 01.18 Rev 2 and the accomplishment instructions in SB 80-02 Rev 2, or use another system that is accepted as an equivalent by the Secretary. (Requirement)\n- Sets a firm compliance cutoff: helicopters used in both IFR (instrument flight rules) and VFR (visual flight rules) operations must have the system fitted before further flight after 31 March 1988. (Compliance)\n- Cancels certain operating limitations previously imposed in the flight manual once the system is installed. (Note 1)\n- States explicitly that complying with earlier issues of this Directive does not satisfy the requirements of this Amendment 2. (Note 2)\n\n**Who is affected**\n\n- Owners, operators and maintenance organisations responsible for all-model Eurocopter AS 355 E/F/F1/F2 helicopters that use the Allison 250 C20F engine. (Applicability)\n- Aircraft maintainers and parts suppliers who will perform and supply the relight systems or equivalent modifications to meet the Service Bulletin instructions.\n- The regulator (the Secretary) who retains discretion to accept “equivalent” systems. (Requirement)\n\n**Why the regulator requires this (claimed purpose) and the immediate effect**\n\n- The Directive states its purpose is safety: there were reported single- and double-engine flameouts in high-humidity, near‑zero‑degree conditions (one was fatal). The relight system is intended to provide automatic relighting capability in those conditions before the Australian winter when such conditions are more likely. (Background)\n- The immediate regulatory effect is to oblige operators either to retrofit the specified automatic relight system or obtain an accepted equivalent and to ground or restrict helicopters that have not complied once the compliance date passes. (Requirement, Compliance)\n\n**Costs, incentives and trade-offs (concrete mechanics)**\n\n- Who pays: the direct cost of parts, labour, downtime and any necessary wiring or engine modifications falls on the aircraft owner/operator and their maintenance provider. (Requirement)\n- Who decides: the Secretary (regulator) has authority to accept alternative systems as “equivalent”; maintainers decide how to meet the SB instructions; manufacturers supply the approved kit. (Requirement)\n- Behaviour change: operators must schedule retrofit work, accept short-term capacity loss while helicopters are out of service, and update maintenance records/flight manuals. After installation, previously imposed flight‑manual operating limitations are removed for that aircraft. (Compliance, Note 1)\n- Compliance burden and implementation risk: the requirement ties compliance to specific Service Bulletin revisions, so operators must source parts and follow those technical instructions exactly or seek regulatory acceptance of alternatives. If kits or approved maintenance facilities are limited, compliance could cause delays, additional transport or payroll costs, and concentrated demand for specific parts or installers.\n- Market effects and concentrated benefits: specifying particular SB revisions and an automatic relight system concentrates demand on manufacturers and suppliers able to meet the SB or produce an accepted equivalent; those suppliers gain a concentrated commercial benefit while costs are spread across many operators. The Directive also amends the SBs to incorporate modifications (350A07‑1910 and 1920) to prevent inadvertent operation of the system, which can add technical scope and parts to the retrofit. (Background, last paragraph)\n- Opportunity cost: time and money spent on the retrofit cannot be used for other upgrades or operations; operators may need to delay flights or lease aircraft to cover capacity shortfalls.\n\n**Discretion, equivalence and enforcement mechanics**\n\n- The regulator retains discretion to accept an “equivalent” system; that discretion creates an approval path but also introduces administrative overhead for an operator seeking an alternative. (Requirement)\n- The Directive explicitly states that earlier compliance with previous issues of the Directive is not sufficient for Amendment 2, so some operators may need to rework prior installations to meet the updated SB Rev 2 instructions. (Note 2)\n\n**Implementation-specific notes drawn from the Directive text**\n\n- The AD references foreign (DGAC/Bureau Veritas) Airworthiness Directives and specific Service Bulletin revisions; operators must follow the current referenced technical documents. (Note and Background)\n- The Directive amends the prior issue to reflect Service Bulletin revisions and to incorporate modifications intended to prevent inadvertent operation of the automatic relight system. (Last paragraph)\n\n"},"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":3,"scope_assessment":{"changed":false,"description":"This amendment remains tightly focused on its original purpose: mandating automatic engine relighting systems for AS 355 helicopters. Amendment 2 updates technical references to newer revisions (Rev 2) and incorporates additional safety modifications (350A07-1910 and 1920) to prevent inadvertent system operation, but does not expand the scope beyond the original safety intent."},"complexity_factors":["Short, single-purpose directive (approximately 300 words)","Only 4 defined model variants in applicability section","Two primary technical references (Aerospatiale SB 01.18 Rev 2 and SB 80-02 Rev 2) with one alternative ('other equivalent system acceptable to the Secretary')","Simple conditional structure: applicability → requirement → compliance deadline","Two cancellation notes modifying previous operational limitations","One explicit non-grandfathering clause (Note 2 regarding previous compliance)","Minimal cross-referencing (one French aviation authority reference: DGAC Bureau Veritas AD 86-153-031 (B) R4)"],"plain_english_summary":"This CASA safety directive requires owners/operators of Eurocopter AS 355 E/F/F1/F2 helicopters to install an automatic engine relight system per Aerospatiale Service Bulletins 01.18 Rev 2 and 80-02 Rev 2 (or an approved equivalent). It targets IFR and VFR operations to prevent dual-engine flameout accidents in cold, humid conditions. Amendment 2 updates technical standards, adds safeguards against unintended activation, and sets a compliance deadline before 31 March 1988; prior compliance with earlier versions is not sufficient."}},"importantCases":[],"_links":{"self":"/api/acts/ad-as-355-28-amdt-2-installation-of-automatic-relighting-system","history":"/api/acts/ad-as-355-28-amdt-2-installation-of-automatic-relighting-system/history","analysis":"/api/acts/ad-as-355-28-amdt-2-installation-of-automatic-relighting-system/analysis","conflicts":"/api/acts/ad-as-355-28-amdt-2-installation-of-automatic-relighting-system/conflicts","importantCases":"/api/acts/ad-as-355-28-amdt-2-installation-of-automatic-relighting-system/important-cases","documents":"/api/acts/ad-as-355-28-amdt-2-installation-of-automatic-relighting-system/documents"}}