AD/B727/213 - Auxilary Fuel Tanks

Applicability: The AD applies to Boeing 727-100 and 727-200 aeroplanes fitted with specified Rogerson STCs. The STC numbers for 727-100 are listed (for example SA2970WE, SA3674WE, SA3157WE, and others) and for 727-200 (SA3065WE and SA1051NW). The Applicability table is the primary filter that determines which aeroplanes must comply.

Requirement and scope: The central legal duty is to deactivate the auxiliary fuel tanks in accordance with an approved deactivation procedure (Requirement). Any auxiliary-tank component that remains installed must be secured and must not affect operational safety or airworthiness. An explicit limitation is imposed: deactivation may not introduce new instructions for continued airworthiness. Appendix A is incorporated as the set of criteria the deactivation procedure should address (Appendix A, opening sentence; Note 1).

Safety rationale: The Background records that the Directive results from manufacturer-conducted fuel system reviews that identified potential unsafe conditions for which the manufacturer had not provided corrective actions. The stated hazard is the potential for ignition sources within fuel tanks in the presence of flammable vapours, which could lead to fuel-tank explosion and loss of the aeroplane (Background). The AD additionally cross-references FAA AD 2008-12-03 and cites one FAA advisory circular for an approved method to secure fuel plumbing (Note 2; Appendix A, para 4).

Required tasks and documentation: Appendix A sets out ten specific actions. These include permanent draining and vapour clearance (para 1); disconnecting and stowing electrical connections for fuel pumps and FQIS (para 2); disconnecting and capping pneumatic interfaces (para 3); disconnecting, capping and securing fuel feed and vent plumbing interfaces at the OEM tank side by an approved method (para 4); pulling and collaring circuit breakers used to operate the auxiliary tank (para 5); revising weight and balance and obtaining CASA approval where required (para 6); amending the AFM to indicate deactivation, removing the STC AFM supplement from effect, and placarding the flight deck (para 7); removing auxiliary-tank maintenance procedures from the aeroplane maintenance manual (para 8); performing leak and pressure checks and verifying OEM FQIS and fuel distribution systems have not been adversely affected before returning to service (para 9); and including any operator-specific relevant information in the operator’s proposed procedures (para 10).

Timing and authority: The AD became effective 28 August 2008 and mandates compliance on or before 16 December 2008 (Compliance; effective date). The AD is issued by the Civil Aviation Safety Authority via a delegate (signed by James Coyne, Delegate of CASA). The AD also explicitly references external FAA material (FAA AD 2008-12-03; FAA AC 25-8) as relevant guidance and methods (Note 2; Appendix A, para 4).

Interaction with STCs and AFM: The AD explicitly requires that the AFM be amended to indicate the auxiliary tank is deactivated and that the AFM Supplement for the STC is not in effect (Appendix A, para 7). That instruction has the operational consequence that the tasks and procedures authorised by the STC are no longer permitted in the AFM.

Primary affected parties: Operators and certificate holders of Boeing 727-100 and 727-200 aeroplanes fitted with any of the listed Rogerson auxiliary fuel-tank STCs are the direct subjects of this AD. The Applicability table lists the precise STC identifiers. Each operator who has such a modification is required to implement the deactivation in accordance with an approved procedure and to achieve compliance by the specified deadline (Applicability; Requirement; Compliance).

Maintenance organisations and engineers: The deactivation work is technical and interacts with fuel system plumbing, electrical systems (FQIS, pumps, float switches), pneumatic interfaces, circuit breakers, and structural considerations in the vent lines. Maintenance organisations that hold approvals to perform fuel-system work, or certificated maintenance engineers, will perform the physical acts described in Appendix A (paras 1-5, 9). They will also be responsible for making the required amendments to maintenance manuals and for performing any leak and pressure checks and verification of OEM systems (para 9).

Regulatory bodies: CASA is the issuing authority and retains oversight functions, specifically approval of revised weight and balance documentation where required (Appendix A, para 6). The AD references FAA materials, signalling coordination with overseas airworthiness authorities (Note 2; Background).

Aircraft owners and operators: Owners and operators bear the direct cost and operational changes. They must amend AFMs and maintenance manuals, apply placards to the flight deck, and ensure any operational supplements for the STC are removed or noted as not in effect (Appendix A, paras 6-8). They must also include any operator-specific information in the proposed deactivation procedures submitted or implemented (para 10).

Third-party suppliers and STC holders: Rogerson Aircraft Corporation is named in the Background as the producer of the auxiliary tanks and as the subject of manufacturer-conducted fuel system reviews. The AD notes that the manufacturer did not provide corrective actions for the identified unsafe conditions; that factual account within the instrument identifies the STC/modification supplier as part of the causal chain (Background). The AD does not impose a remedial obligation on the manufacturer within the text; it places the operational duty on operators to deactivate the installed tanks.

Passengers and users: The AD does not directly regulate passengers but affects aircraft configuration and may constrain operational range and payload planning by removing auxiliary fuel capability, because the STC-associated operations and AFM supplements are to be removed from effect (Appendix A, para 7). The AD itself does not specify operational limits beyond the prohibition of use of the deactivated tanks.

Other stakeholders: Aeroplane insurers, lessors and lessees will be indirectly affected insofar as the aircraft's certificated configuration changes, paperwork is amended, and operational capabilities authorised by the STC are withdrawn. The AD does not address contractual arrangements; those are external commercial matters.

Mandatory duties on operators: Operators of affected aeroplanes must deactivate the auxiliary fuel tanks in accordance with an approved deactivation procedure (Requirement). The AD requires that any remaining components be secured and not affect airworthiness. Operators must complete deactivation on or before 16 December 2008 and record or effect the documentation amendments spelled out in Appendix A.

Specific procedural duties (Appendix A): The Appendix prescribes ten actions that the operator’s deactivation procedure should address. These include permanent draining and vapour clearance (para 1); disconnecting and stowing electrical connections for the fuel quantity indication system, pumps, float switches and other electrical interfaces at the auxiliary-tank interface (para 2); disconnecting and capping pneumatic connections (para 3); disconnecting, capping and securing fuel feed and vent plumbing interfaces at the aeroplane OEM tank side using an approved method, with an explicit recommendation to leave disconnected auxiliary vent lines open and secured to eliminate structural deformation during cabin decompression (para 4); pulling and collaring relevant circuit breakers (para 5); obtaining CASA approval for revised weight and balance documents if required (para 6); amending the AFM and removing the STC AFM Supplement from effect, and placarding the flight deck (para 7); removing auxiliary tank maintenance procedures from the aeroplane maintenance manual (para 8); performing leak and pressure checks and verifying that the aeroplane FQIS and fuel distribution systems have not been adversely affected prior to returning to service (para 9); and including operator-specific steps in the proposed procedures (para 10).

Documentation duties: The operator must revise weight and balance documentation if required and obtain CASA approval for the revision (Appendix A, para 6). The AFM must be amended to indicate the tank is deactivated and to remove operating procedures for the auxiliary tank, and a flight-deck placard is required (para 7). The Appendix allows amelioration by inserting a copy of the Directive into the AFM to accomplish the AFM revisions (para 7). Maintenance manuals must be amended to remove auxiliary-tank maintenance procedures (para 8). Operators must perform and record the required leak and pressure checks and verifications (para 9).

Constraints on deactivation methods: The Requirement contains a non-obvious constraint that deactivation may not result in the need for additional instructions for continued airworthiness. That is framed as a limit on the deactivation solution: the procedure adopted must not create new ongoing maintenance or airworthiness instructions for the aeroplane (Requirement). The Appendix also recommends criteria to avoid ancillary problems, such as out-gassing and structural deformation.

Regulatory rights and approvals: CASA retains the authority to approve weight and balance revisions (Appendix A, para 6). The AD was issued by CASA and became effective on a stated date; CASA’s broader enforcement and oversight powers are implicit in the instrument but the AD text does not set out the full regulatory powers or the process for CASA approvals beyond naming the approval requirement for weight and balance revisions.

No explicit penalties in the AD text: The AD does not contain express penalty provisions or specify enforcement sanctions within its text. The AD instructs deactivation and records a compliance date (Compliance; effective date) but does not set out civil penalty amounts, suspension rights, or criminal offences in the instrument itself.

Enforcement authority: The AD is issued by the Civil Aviation Safety Authority, signed by a CASA delegate. The AD sets an effective date (28 August 2008) and a compliance deadline (on or before 16 December 2008). Those dates create legal obligations for operators of the affected aeroplanes. The instrument explicitly requires CASA approval for any required weight and balance revision (Appendix A, para 6), indicating a direct regulatory approval role for CASA in at least some elements of compliance.

Absence of specified sanctions: The text of the AD does not list specific penalties, fines or punitive measures for non-compliance. The AD prescribes actions and a compliance timeline but does not specify enforcement mechanisms, infringement notices, or administrative penalty amounts within the document itself. Any formal penalties or grounds for grounding an aircraft, suspension of operations, or other enforcement action are not detailed in this AD’s text.

Implied enforcement pathways: While the AD does not state enforcement steps, the fact that it is an Airworthiness Directive recorded by CASA implies that CASA has regulatory oversight and approval authority with respect to airworthiness matters, including approving weight and balance revisions and reviewing operator compliance documentation (Appendix A, para 6). The AD’s requirement that the AFM and maintenance manuals be amended and that placards be installed creates traceable documentary requirements that CASA can inspect. The AD’s references to FAA AD 2008-12-03 and to FAA Advisory Circular AC 25-8 provide accepted technical methods that inspectors can use as benchmarks during oversight (Note 2; Appendix A, para 4). However, any particular enforcement step, such as suspension of an operator’s certificate, grounding of an aircraft, or civil penalties, is not set out in the AD itself.

Compliance date implication: The AD sets a clear compliance deadline. From a practical and regulatory perspective, failure to meet a compliance date on an instrument of this type typically exposes an operator to CASA oversight and potential enforcement action under CASA’s broader regulatory regime, but this AD text does not specify those broader powers or procedures. Users should treat the compliance date as mandatory and work with CASA on approvals where required.

Documentary evidence for inspections: Appendix A provides steps and documentation changes (AFM insert, placard, maintenance manual amendment, weight and balance approval, and evidence of leak and pressure checks and FQIS/distribution verification). These documentary elements create records that CASA may request during compliance checks or audits, and form the practical basis for proving compliance even though the AD does not set out a penalty schedule.

Reference to foreign authority and guidance: The AD explicitly references FAA AD 2008-12-03 (Note 2) and cites FAA Advisory Circular AC 25-8 as an example of an approved method for capping fuel plumbing interfaces (Appendix A, para 4). This demonstrates interaction with United States airworthiness materials and is typical of cross-jurisdictional adoption of technical standards for modifications and repairs. The AD adopts the FAA’s AD as a relevant reference point rather than restating the FAA material in full.

Interaction with STCs and AFM supplements: The AD directly affects the legal effect of STC-based AFM supplements. Appendix A requires amendment of the AFM to indicate that the auxiliary tank is deactivated and instructs that the AFM Supplement for the STC is not in effect (para 7). That modifies the set of operationally authorised procedures for the aeroplane by removing the STC supplement from active effect. The AD thus changes the authorised configuration and operational documentation for the affected aircraft.

Modification of maintenance and airworthiness documentation: The AD requires changes to the aeroplane maintenance manual (remove auxiliary-tank maintenance procedures), the AFM (remove STC supplement and place placard), and may require a revised weight and balance document subject to CASA approval (Appendix A, paras 6-8). These amendments interact with the operator’s regulatory obligations to maintain accurate and approved aircraft documentation and with any continuing airworthiness obligations the operator has under CASA rules.

No express cross-reference to Australian civil penalty statutes: The AD text does not reference particular provisions in the Civil Aviation Act or Civil Aviation Safety Regulations regarding enforcement, nor does it set out statutory penalties. Therefore, statutory enforcement measures that CASA might use under its general regulatory framework are not invoked within the AD itself. External statutes and CASA’s general regulatory powers will determine enforcement in practice, but the AD does not articulate that legal detail.

Technical interaction with OEM systems: The AD requires that disconnection and capping of plumbing be carried out such that fuel plumbing interfaces at the aeroplane OEM tanks are capped and secured in accordance with an approved method, citing FAA AC 25-8 as one example (Appendix A, para 4). The AD also requires verification that the aircraft fuel quantity indication system and fuel distribution systems have not been adversely affected by the deactivation (para 9). Those requirements implicate interaction between the deactivation steps and the OEM-approved systems and documents. Any deactivation that alters OEM systems must therefore be reconciled with manufacturer-approved methods or acceptable practices.

No contractual or commercial law directives in the AD: The AD does not prescribe how operators manage contractual relations with lessors, insurers or maintenance providers, nor does it change ownership rights. It alters airworthiness status and documentation, which will have knock-on commercial effects, but contractual impacts are not addressed in the AD text.

Single-issue instrument with no internal amendments: The AD document supplied contains an effective date (28 August 2008) and a compliance date (on or before 16 December 2008) and is labelled AD/B727/213 (9/2008). The AD text does not contain any subsequent amendment notes, supersessions or revocations within the supplied document. The header repeats AD/B727/213 and the 9/2008 date in several places, but no later amendments are recorded in the text provided.

Referenced external amendments: The AD refers to FAA AD 2008-12-03 Amdt 39-15546 (Note 2, Background). That reference is to an FAA action rather than an amendment to this CASA AD. The AD also references FAA Advisory Circular AC 25-8 as an example of an approved method for capping plumbing interfaces (Appendix A, para 4). The supplied instrument does not indicate whether it incorporates or follows any prior CASA ADs or whether it supersedes anything in CASA records.

No in-text revision log: The supplied document does not include an amendment history table, cumulative amendment references, or notes indicating prior versions. The only dates present are the effective date, the signing date (16 July 2008, near the signature), and the compliance deadline (16 December 2008). The document indicates it became effective on 28 August 2008 and was signed by a CASA delegate on 16 July 2008, but there is no record of later changes to the AD text shown.

Implication for users: Because the instrument is presented as a single AD without recorded amendments, operators should treat the text as binding for the stated effective and compliance dates and should consult CASA for any later changes or superseding directives. The AD explicitly suggests following Appendix A criteria and notes FAA references; any later revisions, replacements or cancellations would be published by CASA separately and are not contained in this AD text.

No litigation or case references in the document: The AD contains no references to litigation, judicial decisions, or judicial review. The text does not mention any disputes, legal challenges, or court outcomes related to this directive. It contains a technical background attributing the action to manufacturer fuel-system reviews and an FAA reference, but does not record any legal proceedings.

No adjudicative history provided: The AD itself is an administrative regulatory instrument issued by CASA. The supplied instrument does not include any administrative appeals, review process timelines, or mention of rights to appeal or internal review within the AD text. There is no record of contested decisions or procedural history in the document provided.

Implication for practitioners: Because the AD does not contain litigation history or appellate outcomes, operators and advisers seeking to understand the legal context or any precedent must consult external CASA materials, administrative law channels, or court records beyond this instrument. The AD does not supply any such records, and practitioners should treat the AD as a discrete regulatory requirement that may nonetheless be subject to broader regulatory enforcement or challenge under relevant administrative law frameworks not described here.

Deactivation must not create new continued airworthiness instructions: The Requirement expressly states that deactivation may not result in the need for additional instructions for continued airworthiness. That is a less obvious constraint because many deactivation methods could create new inspection or maintenance requirements. Operators must design the deactivation to be effectively maintenance-free with respect to continued airworthiness instructions, or justify how any residual requirements do not amount to new ongoing instructions (Requirement; Appendix A, para 10). This limits acceptable methods and will affect engineering choices.

Capping and vent handling specifics: Appendix A requires that fuel feed and fuel vent plumbing interfaces be disconnected and capped at the aeroplane OEM tank side and secured in accordance with an approved method; it cites FAA AC 25-8 as an example (para 4). It further instructs that, to prevent structural deformation during cabin decompression, disconnected auxiliary fuel tank vent lines should be left open and secured. Those two instructions can appear in tension: operators must cap fuel feed and vent plumbing at the tank side, yet leave the disconnected vent lines open and secured to prevent structural deformation. Failure to observe the vent-line instruction could create structural risk during decompression testing or events (Appendix A, para 4).

Electrical and avionics interfaces: The Appendix mandates full disconnection of FQIS electrical connections and related fuel-pump electrical circuits, and requires stowing those connections at the auxiliary tank interface (para 2). Operators must ensure the FQIS disconnection does not interfere with the OEM fuel quantity indication system or create false warnings or unanticipated cockpit indications. Appendix A further requires verification that the aeroplane FQIS and fuel distribution systems have not been adversely affected (para 9). Practical gotchas include unintended changes to cockpit indications, failure of integrated warning logic, or the need to reconcile avionics wiring in ways that are not self-evident.

Circuit breaker handling: The Appendix explicitly requires pulling and collaring circuit breakers used to operate the auxiliary tank (para 5). This is a physical and procedural requirement that must be documented and visible. Operators must ensure that these breakers are not inadvertently restored to service, and that associated cockpit checks are updated accordingly. Collaring and clearly documenting the breakers is required to show the auxiliary component is deactivated.

Weight and balance approval: Deactivation may change the aeroplane weight and balance. Appendix A requires revision of the weight and balance document and obtaining CASA approval if required (para 6). Operators must not return the aeroplane to service with an unapproved weight and balance amendment. Failure to obtain CASA approval where required may create a regulatory non-compliance independent of the physical deactivation work.

AFM and maintenance manual amendments: The Appendix requires removal of STC operating procedures from the AFM and removal of auxiliary tank maintenance procedures from the maintenance manual (paras 7-8). Operators should ensure that these document changes are made correctly and that any AFM supplements are clearly marked as not in effect. The Appendix suggests that inserting a copy of this AD into the AFM may accomplish the AFM revisions (para 7), but operators must check whether that method satisfies other regulatory documentation requirements.

Leak, pressure and system verification before return to service: Appendix A requires leak checks, pressure checks and verification that OEM FQIS and fuel distribution systems are unaffected before return to service (para 9). Operators must plan for these checks and for potential mitigation if OEM systems are found to be affected. If checks reveal an adverse effect, the operator must resolve it prior to return to service; however, the AD forbids deactivation methods that create ongoing continued-airworthiness instructions (Requirement), so resolution approaches must be consistent with that constraint.

Recordkeeping and proof of compliance: While the AD requires documentation changes and physical evidence, it does not prescribe a specific form for compliance records. Operators should retain work cards, maintenance release documentation, weight and balance approvals, AFM and maintenance manual amendment records, placard photos, and verification check evidence to demonstrate compliance at audit or inspection. The lack of a specified format is a practical gap that operators must fill.

Interaction with STC legal status: Appendix A requires that the AFM Supplement for the STC be indicated as not in effect (para 7). Operators must ensure that removal of STC procedures from operational documentation does not conflict with STC-holder obligations or contractual arrangements with the STC supplier. The AD does not direct the STC holder to remove or modify the STC, so the STC remains on the aircraft physically unless components are removed; operators must ensure that legal and maintenance positions match the physical configuration.

Timing pressure: The compliance date is short relative to typical maintenance scheduling windows. The AD became effective 28 August 2008 with compliance by 16 December 2008. Operators should note the time bound and prepare schedules, parts, and approvals early to avoid being non-compliant by the deadline.

Adopt an approved deactivation procedure that implements Appendix A: The AD requires deactivation in accordance with an approved procedure and Appendix A provides the criteria that should be included. A compliant procedure should explicitly address all ten Appendix A items: drain and vapour clearance; disconnect and stow electrical connections; disconnect and cap pneumatic connections; disconnect/cap and secure fuel feed and vent plumbing at the OEM tank side using an approved method; pull and collar circuit breakers; revise weight and balance and obtain CASA approval where required; amend AFM and maintenance manual and placard the flight deck; perform leak and pressure checks and verify FQIS and fuel distribution systems; and include any operator-specific steps (Appendix A, paras 1-10).

Step-by-step practical checklist based on Appendix A

• Planning and approvals: confirm the aircraft is listed in the Applicability table and schedule deactivation work ahead of the compliance deadline. Prepare a deactivation procedure for approval if the operator’s procedures require CASA review; include the Appendix A criteria and any operator-specific steps (Appendix A, paras 1, 10).
• Drain and vapour clearance: permanently drain the auxiliary tanks and clear them of fuel vapours to eliminate out-gassing risk; if the auxiliary tank contains a bladder and bladder removal is applicable, consider removal to assist vapour elimination (Appendix A, para 1).
• Electrical disconnection: disconnect all electrical connections for FQIS, fuel pumps, float switches and any other auxiliary-tank electrical circuits and stow those connections at the auxiliary-tank interface as specified (Appendix A, para 2).
• Pneumatic connections: disconnect pneumatic interfaces and cap them at the pneumatic source and secure them (Appendix A, para 3).
• Fuel plumbing: disconnect fuel feed and vent plumbing interfaces with the OEM tanks, cap at the aeroplane tank side and secure using an approved method; FAA AC 25-8 is cited as one approved method (Appendix A, para 4). When handling vent lines, leave disconnected auxiliary vent lines open and secured to avoid structural deformation during cabin decompression.
• Circuit breakers: pull and collar all circuit breakers that operate the auxiliary tank and document their status (Appendix A, para 5).
• Weight and balance: assess the impact of the deactivation on weight and balance; revise the relevant document and obtain CASA approval if required before returning to service (Appendix A, para 6).
• AFM and placarding: amend the AFM to indicate the auxiliary tank is deactivated, remove auxiliary tank operating procedures and indicate that the AFM Supplement for the STC is not in effect; place a placard in the flight deck indicating deactivation. The Appendix recognises that inserting a copy of the Directive into the AFM may accomplish the AFM revision (Appendix A, para 7).
• Maintenance manual: amend the aeroplane maintenance manual to remove auxiliary tank maintenance procedures (Appendix A, para 8).
• System verification and return-to-service checks: perform leak and pressure checks and other necessary procedures to verify that the FQIS and fuel distribution systems have not been adversely affected before returning the aeroplane to service. Record the checks and their outcomes (Appendix A, para 9).
• Record inclusion and operator-specific steps: include any operator-specific relevant information or additional steps that the operator deems necessary in the proposed procedures submitted or kept on file, as Appendix A invites operator input (para 10).

Documentation to retain for compliance evidence: work-pack records for drain and disconnection steps; photos of circuit breaker collars and flight-deck placard; amended AFM pages or AFM insert with the AD; maintenance manual amendment records; CASA approval for weight and balance revisions where required; leak and pressure check reports; and a written deactivation procedure showing how Appendix A was satisfied.

Use referenced approved methods where applicable: when capping fuel plumbing interfaces, follow an approved method such as FAA AC 25-8 or other acceptable method recognised by CASA (Appendix A, para 4). Where CASA approval is required, submit the method to CASA in advance if practicable.

Coordination with maintenance organisations and CASA: plan for CASA approval of weight and balance amendments if required and engage maintenance organisations with fuel-system experience. Given the AD references FAA material and the STC origin, coordinate technical standards with CASA so the deactivation meets Australian airworthiness expectations.

Testing and verification: ensure that post-deactivation testing includes checks that FQIS remains functional for OEM tanks and that no residual wiring or plumbing creates false inputs or leakage risk. Appendix A requires verification that OEM FQIS and fuel distribution systems have not been adversely affected (para 9).

Timely completion and compliance proof: complete the deactivation on or before the compliance date (on or before 16 December 2008) and maintain documentary evidence that each Appendix A step was completed and that CASA approvals were obtained where required. The AD became effective on 28 August 2008 and was signed by a CASA delegate (Background; effective date).

Further action if problems are found: if leak, pressure or system verification uncovers adverse effects on OEM systems, do not return the aeroplane to service until those issues are resolved. Because the AD disallows deactivation solutions that generate ongoing continued-airworthiness instructions (Requirement), any remedial work should be designed to avoid imposing new continued-airworthiness tasks where possible and must be discussed with CASA as required.