{"id":"F2009L01570","name":"AD/B727/217 - Fuel Tank Safety","slug":"ad-b727-217-fuel-tank-safety","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":78303,"registerId":"commonwealth-F2009L01570-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 727 Series Aeroplanes","sectionType":"division","heading":"Boeing 727 Series Aeroplanes","content":"### Boeing 727 Series Aeroplanes\n\n| AD/B727/217 | Fuel Tank Safety | 5/2009 |\n| ----------- | ---------------- | ------ |\n\n| Applicability: | Model 727, 727C, 727-100, 727-100C, 727-200, and 727-200F series aeroplanes, certificated in any category; as identified in Boeing Alert Service Bulletin (ASB)727-28A0128, dated 4 April 2008.                                                                                                                                                     |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Install new ground fault interrupter (GFI) relays for the main fuel tanks and the auxiliary fuel tank pumps and do all the other specified actions by accomplishing all the applicable actions specified in the Accomplishment Instructions of ASB 727-28A0128.                                                                                  |\n|                | 2. For aeroplanes identified as Groups 5 through 18 inclusive, in ASB727-28A0128, carry out the following actions in accordance with the Accomplishment Instructions of Boeing ASB 727-28A0130, dated30 April 2008.                                                                                                                                 |\n|                | a. Install new ground blocks, track, switch mounting bracket, relay mounting bracket, toggle switches, and relays, and make changes to the wire bundles in the GFI relay panel in the electronic equipment bay.                                                                                                                                     |\n|                | b. Install new circuit breakers and lights and make changes to wire bundles on the third crewman's P6 and P4 panels in the flight compartment.                                                                                                                                                                                                      |\n|                | 3. Revise the approved maintenance program by incorporating Airworthiness Limitations 28-AWL-16 and 28-AWL-17 of Section D of \"Boeing 727-100/200 Airworthiness Limitations (AWLs),'' Document D6-8766-AWL, RevisionAugust 2007.                                                                                                                    |\n|                | After accomplishing the Requirement 3 revision to the approved maintenance program, no alternative inspections or inspection intervals may be used, unless the inspections or intervals are approved by the United States Federal Aviation Administration (FAA) as an alternative means of compliance (AMOC) to paragraph (h) of FAA AD 2009-05-03. |\n|                | Later revisions of ASB 727-28A0128 or 727-28A0130, approved by the FAA as AMOCs to FAA AD 2009-05-03, are considered acceptable for compliance with the equivalent Requirements of this Directive.                                                                                                                                                  |\n|                | Note: FAA AD 2009-05-03 Amdt 39-15827 refers.                                                                                                                                                                                                                                                                                                       |\n\n| Compliance: | For Requirement 1 -Within 60 months after the effective date of this Directive.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |\n| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|             | For Requirement 2 and 3 - Concurrently with Requirement 1.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |\n|             | This Airworthiness Directive becomes effective on 7 May 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |\n| Background: | This Directive results from fuel system reviews conducted by the manufacturer. The Directive is issued to prevent an electrical fault in the fuel pump system, which might cause a connector or end cap to burn through and a subsequent fire or explosion inside the fuel pump or wing spar area. The Directive is also issued to prevent uncommanded operation of the auxiliary fuel tank pumps, which can cause them to run dry. This condition will increase pump temperature and could supply an ignition source to fumes in the fuel tank, which can result in a consequent fire or explosion. |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n26 March 2009","sortOrder":0},{"sectionNumber":"AD/B727/217","sectionType":"part","heading":"AD/B727/217","content":"## AD/B727/217","sortOrder":1},{"sectionNumber":"Fuel Tank Safety","sectionType":"part","heading":"Fuel Tank Safety","content":"## Fuel Tank Safety","sortOrder":2},{"sectionNumber":"5/2009","sectionType":"part","heading":"5/2009","content":"## 5/2009","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The Directive implements targeted hardware retrofits and maintenance-program changes intended to address fuel-system ignition risks identified in manufacturer reviews. It remains within the original safety-focused scope (preventing electrical faults and uncommanded pump operation that could create ignition sources in fuel tanks). The instrument does not expand into unrelated regulatory areas or add new safety objectives beyond those described in the Background; it does, however, formalise ongoing inspection requirements and ties alternative compliance options to FAA AMOCs, which increases regulatory linkage but does not materially change the Directive’s core purpose."},"complexity_factors":["Multiple, distinct mandatory actions (three numbered Requirements) with different technical content","Cross-references to three external Boeing documents (ASB 727-28A0128; ASB 727-28A0130; AWLs document D6-8766-AWL) that contain the detailed technical steps","Dependency on FAA approval for alternative means of compliance (AMOC) and for acceptance of later ASB revisions (introduces external regulatory dependency)","Conditional scope: additional hardware/work required only for aeroplanes listed as Groups 5–18 in the ASB (group-based applicability)","Operational deadline (60 months) for main retrofit plus concurrent timing for other requirements (scheduling complexity)","A prohibition on alternative inspections/intervals unless FAA AMOC is obtained (restricts operator flexibility and creates procedural complexity)","Technical installation work (wiring changes, relay/circuit-breaker swaps, panel modifications) that typically requires specialised maintenance procedures and parts availability considerations"],"plain_english_summary":"**What this rule does (mechanically)\n\n- Requires physical modifications to the fuel pump electrical system on specified Boeing 727 series aeroplanes. Specifically:\n  - Requirement 1: install new ground fault interrupter (GFI) relays for the main and auxiliary fuel tank pumps and complete all actions in Boeing Alert Service Bulletin (ASB) 727-28A0128 (dated 4 April 2008). (GFI relays are devices that interrupt power if an electrical fault to ground is detected.)\n  - Requirement 2: for aeroplanes listed as Groups 5–18 in ASB 727-28A0128, carry out additional hardware changes per Boeing ASB 727-28A0130 (dated 30 April 2008). These include installing new ground blocks, tracks, mounting brackets, toggle switches, relays and making specified wiring changes in the electronic equipment bay and flight deck panels.\n  - Requirement 3: revise the approved maintenance program to include two specific Airworthiness Limitations (28-AWL-16 and 28-AWL-17) from Boeing’s 727-100/200 AWLs document (Revision August 2007). After incorporation, operators cannot use alternative inspection methods or intervals except where the U.S. Federal Aviation Administration (FAA) approves an alternative means of compliance (AMOC).\n- Timing: the hardware installation called for in Requirement 1 must be completed within 60 months of the Directive’s effective date; Requirements 2 and 3 are to be done concurrently with Requirement 1.\n- Cross-acceptance: later revisions of the named Boeing ASBs are acceptable for compliance only if approved by the FAA as AMOCs to FAA AD 2009-05-03.\n\nWho this affects\n\n- Owners and operators of Boeing 727, 727C, 727-100, 727-100C, 727-200 and 727-200F aeroplanes that match the serial/identification criteria in Boeing ASB 727-28A0128.\n- Maintenance organisations and engineers who perform the retrofit and who must update the aircraft’s approved maintenance program.\n- Regulators: the Directive is enforced by the Australian Civil Aviation Safety Authority (CASA) but depends on FAA approvals for alternative compliance paths.\n\nWhy it matters (stated purpose and mechanical effect)\n\n- The directive aims to reduce the risk of electrical faults in the fuel pump system that could burn through connectors or end caps, cause fuel pump fires or explosions, or result in uncommanded auxiliary pump operation that might run pumps dry and create ignition sources inside fuel tanks (see Background). Mechanically, the rule reduces those risks by adding ground-fault protection, changing wiring and mounting arrangements, and imposing mandatory inspection/task requirements in the maintenance schedule.\n\nCosts, who pays, and trade-offs\n\n- Who pays: aircraft owners/operators pay for parts, labour, engineering work to install new hardware, wiring changes, and any required maintenance-program paperwork and potential downtime. Maintenance organisations incur the time cost and may need training or tooling changes.\n- Concentrated benefits vs diffuse costs: the safety benefit accrues to each aircraft/operator and to passengers/crew and industry risk exposure; the direct costs are concentrated on the aircraft owners/operators who must perform the retrofit.\n- Operational impact: installations and wiring changes will cause aircraft downtime while work is performed. Incorporating AWLs into the approved maintenance program removes flexibility to adopt alternate inspection intervals without FAA approval (increasing ongoing compliance burden unless an AMOC is granted).\n- Regulatory dependence: the Directive ties alternative compliance to FAA AMOCs. Operators seeking different solutions must secure FAA acceptance for those alternatives, which adds a layer of external approval and potential delay.\n\nImplementation and compliance risks\n\n- Supply and technical risk: obtaining correct parts and skilled labour for wire-bundle rework and relay/circuit-breaker installations can cause scheduling challenges.\n- Certification/acceptance risk: proposed alternative methods or intervals require FAA AMOC approval; CASA’s acceptance of later Boeing ASB revisions is conditioned on FAA approval.\n- Inspection/maintenance enforcement risk: once AWLs are part of the approved maintenance program, audits and oversight will enforce compliance with the new, non-waivable intervals and tasks unless an AMOC exists.\n\nKey references in the Directive\n\n- Boeing ASB 727-28A0128 (4 April 2008) — primary retrofit instructions (Requirement 1).\n- Boeing ASB 727-28A0130 (30 April 2008) — additional hardware/wiring instructions for Groups 5–18 (Requirement 2).\n- Boeing 727-100/200 Airworthiness Limitations Document D6-8766-AWL, Revision August 2007 — contains Airworthiness Limitations 28-AWL-16 and 28-AWL-17 to be inserted into the approved maintenance program (Requirement 3).\n- The Directive accepts FAA AD 2009-05-03 and FAA AMOCs as the path for alternate compliance.\n\nNet effect in plain terms\n\n- Operators of the listed 727 types must retrofit ground-fault protection and make wiring/mounting changes and must update their maintenance programs to include two specific AWLs. They pay for and schedule the work; regulators enforce completion within a 60-month window and restrict alternative inspection practices unless FAA approval is obtained. The mechanical effect is to add electrical protection and mandatory inspection tasks intended to lower the chance of ignition sources inside fuel tanks.\n\n(References: Requirement 1, Requirement 2(a)–(b), Requirement 3, Compliance timing, Background.)"},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — it addresses specific fuel tank safety issues identified in Boeing 727 aircraft through manufacturer fuel system reviews. The references to FAA ADs and Boeing service bulletins are standard practice for Australian aviation safety directives and do not represent scope creep beyond the original safety purpose."},"complexity_factors":["Multiple nested requirements with cross-references to external Boeing documents (ASB 727-28A0128 and ASB 727-28A0130)","Conditional applicability — Requirement 2 only applies to specific aircraft groups (5-18) identified in the service bulletin","Incorporation by reference of US FAA regulations (FAA AD 2009-05-03) and Boeing Airworthiness Limitations Document D6-8766-AWL","Restriction on alternative compliance methods — explicitly prohibits alternative inspections unless approved as AMOCs (Alternative Means of Compliance) by the FAA","Technical aviation terminology throughout (GFI relays, wire bundles, P6/P4 panels, AWLs) requiring domain knowledge","Dual compliance timing — Requirement 1 has its own deadline, while Requirements 2 and 3 must be done concurrently with Requirement 1"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of Boeing 727 series aircraft in Australia to fit ground-fault interrupter relays (and, for certain aircraft, additional switches, breakers, brackets and rewiring) and to update maintenance manuals with two mandatory airworthiness limitations. It addresses the risk that electrical faults in fuel pump wiring could ignite fuel vapours or cause pump overheating and fires. Work must be done within 60 months of May 2009; alternate inspection schedules need FAA approval."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-217-fuel-tank-safety","history":"/api/acts/ad-b727-217-fuel-tank-safety/history","analysis":"/api/acts/ad-b727-217-fuel-tank-safety/analysis","conflicts":"/api/acts/ad-b727-217-fuel-tank-safety/conflicts","importantCases":"/api/acts/ad-b727-217-fuel-tank-safety/important-cases","documents":"/api/acts/ad-b727-217-fuel-tank-safety/documents"}}