AD/B737/347 Amdt 1 - Centre Wing Tank Autoshutoff Wiring

The core technical problem set out in the AD is an incorrect wiring condition affecting the Centre Wing Tank (CWT) autoshutoff system on certain Boeing 737 variants. The AD identifies four interlocking technical facts: (1) an autoshutoff system was installed per Boeing ASB 737-28A1206 dated 11 January 2006, (2) functional tests required by that service bulletin do not reliably detect the incorrect wiring condition ("Functional tests conducted in accordance with that service bulletin are not adequate to detect the incorrect wiring condition"), (3) when the flightcrew manually turns off the CWT pump switches the incorrect wiring may cause the left-hand pump to remain energised while the right-hand pump is switched off, and (4) the low-pressure indicator lights can turn off incorrectly, falsely indicating to the flightcrew that both pumps are de-energised. The engineering failure mode is therefore both electrical (incorrect wiring creating an unintended circuit) and human-factors (misleading cockpit indications).

Regulatory mechanism: the AD operates by mandating performance of the actions contained in FAA Emergency AD 2008-24-51. The amendment deletes the original AD text and adopts the FAA AD by reference, explicitly to "facilitate easier cross referencing to FAA AD 2011-18-03 Amdt 39-16785 which details the terminating actions for the requirements of this AD." In practice this means the CASA instrument invokes foreign regulator documentation as the operative compliance instructions.

Scope and limiting conditions: Applicability is narrowly defined to particular Boeing 737 models (737-600, -700, -700C, -800 and -900 series) and only to aeroplanes where Boeing ASB 737-28A1206 dated 11 January 2006 has been accomplished. The AD therefore applies to the intersection of aircraft type and a particular modification/service-bulletin action having been implemented. The AD keeps in force previously approved exclusions and alternate methods of compliance established prior to the amendment's effective date, and it also accepts FAA-approved AMOCs for FAA AD 2008-24-51 as satisfying this AD.

Safety rationale: The background ties the directive to specific failure incidents and a hazard pathway: continuous running of a fuel pump can produce local overheating of parts inside the fuel pump, which in turn "could produce an ignition source inside the fuel tank." The AD's objective is operational mitigation of that hazard by ensuring the wiring and/or procedures prevent the pump running when deselected and that indications are reliable.

Document architecture: the amendment functions as a vehicle to rely on and align with FAA rulemaking. It references FAA Emergency AD 2008-24-51 as the required compliance text and FAA AD 2011-18-03 as the source of terminating actions. The administrative features include retention of pre-existing AMOCs and confirmation that the compliance date is unchanged from the original AD issue.

Incentive structure embedded in the instrument: operators are required to perform the FAA-prescribed corrective actions unless they have a pre-existing approved exclusion or AMOC. Operators can also rely on FAA-approved AMOCs. The state (CASA) defers some technical judgment to the FAA by incorporating its AD and accepting FAA-approved AMOCs. The instrument therefore centralises the technical corrective prescriptions in another regulator's documents while imposing them as mandatory for the specified Australian-registered aeroplanes.

The AD's text defines a focussed group of affected parties by model and prior work history. Directly affected parties are operators, lessors, and maintenance organisations responsible for Model 737-600, -700, -700C, -800 and -900 series aeroplanes on which Boeing Alert Service Bulletin 737-28A1206 dated 11 January 2006 has been accomplished. The "Applicability" clause in the AD specifies this intersection: those aircraft that both are of the listed models and have had that Boeing ASB action completed are inside the regulatory net.

Maintenance organisations and maintenance personnel are affected because the mandated actions are technical corrections to wiring and/or tests described in FAA Emergency AD 2008-24-51. The AD explicitly finds that "Functional tests conducted in accordance with that service bulletin are not adequate to detect the incorrect wiring condition"; this places an obligation on maintenance providers to implement the FAA-prescribed corrective actions rather than relying solely on the previously-applied ASB functional test procedures.

Flightcrew are an indirectly affected group because the failure mode involves cockpit indications and manual pump switching. The instrument's background narrative describes how "when the flightcrew manually turns off the CWT pump switches, that action turns off the right-hand pump, but re-energizes the left-hand pump due to incorrect wiring" and that "The low-pressure lights turn off, incorrectly indicating to the flightcrew that power to both pumps has been removed." This means operational procedures and crew awareness are relevant to risk mitigation, though the AD mandates technical fixes rather than new crew operating procedures.

Boeing and component suppliers are stakeholders: the AD references Boeing's Alert Service Bulletin (ASB 737-28A1206) as the installation route for the autoshutoff system and declares that the incorrect wiring condition can occur on aeroplanes where the autoshutoff system was installed per that ASB. The AD also references FAA ADs and Boeing service information as the technical sources, so manufacturers are implicated in providing and updating corrective instructions.

Regulatory actors include CASA (the document is issued by a delegate of CASA) and the FAA, because the AD incorporates FAA Emergency AD 2008-24-51 and accepts FAA-approved alternative methods of compliance. The instrument therefore affects interactions between Australian operators and the FAA regulatory framework, insofar as FAA approvals and terminating actions are relied upon.

Lessors, insurers and compliance officers for airlines that operate the affected models are also indirectly affected: the AD creates an actionable maintenance and compliance requirement that will be recorded against aircraft and must be satisfied to remain in conformity with the AD. The AD also preserves prior exclusions or AMOCs that were in force before the amendment, which matters to operators who already had bespoke arrangements.

Finally, because the AD states that the original issue became effective on 20 November 2008 and that the amendment's effective date is 30 September 2011, parties with compliance programmes must be mindful of retrospective continuity for prior AMOCs and the unchanged compliance date. The document does not mention passengers, suppliers beyond Boeing, or other aviation actors; its scope is the aircraft types and the maintenance/operational actors responsible for those aeroplanes.

Duties imposed:

• Perform the actions detailed in FAA Emergency AD 2008-24-51. The AD's "Requirement" clause is explicit: "Perform the actions as detailed in FAA Emergency AD 2008-24-51." That is the operative compliance obligation imposed by the instrument.
• Ensure that, if the aircraft is within the Applicability set (Model 737-600, -700, -700C, -800 and -900 series and Boeing ASB 737-28A1206 dated 11 January 2006 has been accomplished), the FAA-specified corrective actions are carried out. The AD ties applicability directly to that combination, so duty attaches only to those aircraft so described.

Rights and permitted alternatives:

• Existing exclusions or alternate methods of compliance (AMOCs) that were in force before the amendment continue to be in force: "an exclusion or an alternate method of compliance that was in force before the coming into effect of AD/B737/347 Amdt 1 continues to be in force." This preserves previously approved bespoke compliance arrangements.
• Alternative methods of compliance for FAA AD 2008-24-51 that were approved by the FAA are acceptable as a means of compliance against this CASA AD: "Alternative methods of compliance for AD 2008-24-51 that are approved by the FAA are acceptable as a means of compliance against this AD." This gives operators the right to rely on FAA-approved AMOCs rather than re-seeking CASA-specific approvals, as long as the AMOC pre-exists or is FAA-approved.

Interaction with terminating actions:

• The amendment incorporates FAA AD 2011-18-03 Amdt 39-16785 by reference to facilitate easier cross-referencing to the terminating actions for the requirements of this AD. In practical terms the AD signals that operators may rely on the FAA-prescribed terminating actions to discharge ongoing obligations under the CASA AD.

Administrative details relevant to duties and rights:

• The AD becomes effective on 30 September 2011; the original issue of the AD became effective on 20 November 2008. The compliance date "remains unchanged to that detailed in the original issue of this directive." Operators must therefore check what the original compliance deadline was (the AD indicates continuity) and meet that deadline.
• The AD deletes the original text and substitutes incorporation of the FAA AD by reference, meaning that the detailed remedial steps and any timelines, inspections, or workmanship standards that the operator must follow will be those contained in the referenced FAA AD and associated Boeing service documents.
• The directive suggests that functional tests specified in the Boeing ASB are inadequate to detect the wiring fault: "Functional tests conducted in accordance with that service bulletin are not adequate to detect the incorrect wiring condition." This implies an incumbent duty to follow the FAA emergency AD's specific test and inspection procedures rather than relying on the ASB's prior functional tests.

Delegation and provenance:

• The instrument is issued by a CASA delegate (the footer shows "Mike Higgins, Delegate of the Civil Aviation Safety Authority"). The AD therefore represents exercise of CASA's administrative authority via a delegate.

What the AD does not state as rights or duties:

• The text does not specify sanctions, enforcement mechanisms, or criminal or civil penalties for non-compliance within the document itself. It also does not describe any appeals process or the precise administrative pathway for seeking CASA-specific AMOC approvals beyond the preservation of existing ones and acceptance of FAA-approved AMOCs.

In short, the duty is to perform the FAA Emergency AD 2008-24-51 actions for applicable aircraft; operators retain the right to rely on prior exclusions or FAA-approved AMOCs; and terminating actions are to be taken in accordance with the FAA AD incorporated by reference.

The text of this AD does not set out any penalties, fines, or explicit enforcement steps. The document itself comprises an airworthiness directive that "requires" performance of actions specified by the FAA Emergency AD 2008-24-51, but it contains no provision that prescribes a penalty regime, infringement notices, or civil/criminal sanctions within the AD text as provided. The AD does identify the issuing authority as a delegate of the Civil Aviation Safety Authority ("Mike Higgins, Delegate of the Civil Aviation Safety Authority") and sets an effective date ("This Amendment becomes effective on 30 September 2011"), which establishes the instrument as an operative regulatory requirement from that date.

Because the AD incorporates FAA ADs by reference and accepts FAA-approved alternative methods of compliance, the document defines the technical and procedural compliance obligations through those external instruments rather than by detailing enforcement provisions itself. The AD also specifies that "Alternative methods of compliance for AD 2008-24-51 that are approved by the FAA are acceptable as a means of compliance against this AD," which creates an explicit compliance pathway accepted by CASA for FAA-approved AMOCs.

What the AD explicitly leaves unaddressed:

• No penalties, sanctions, or enforcement processes are specified in the body of the AD provided. The AD does not state what administrative or legal consequences will follow if an operator fails to perform the FAA-specified corrective actions by the applicable compliance date. The AD also does not specify the process for CASA to verify compliance, nor does it specify any reporting or certification steps within the text reproduced here.

Operational consequence for practitioners:

• Although the document does not articulate enforcement measures, the AD imposes mandatory corrective actions. Practitioners should therefore treat the AD as an operative compliance obligation that must be satisfied in accordance with the FAA Emergency AD it incorporates, and should be prepared to document compliance and to rely on any pre-existing or FAA-approved AMOCs that they have in place. The AD's own text preserves pre-existing exclusions or AMOCs that were in force prior to the amendment, which is an administrative protection for parties already authorised under previous arrangements.

Practical next steps given the absence of penalty language in the text:

• Operators should ensure that they have implemented the FAA Emergency AD 2008-24-51 actions for applicable aeroplanes and that records reflect that work. If an operator believes an alternative approach is appropriate, they should ensure an FAA-approved AMOC exists (since the AD accepts FAA-approved AMOCs) or confirm whether an existing pre-amendment AMOC remains in force. The AD's lack of penalty specification in the text does not negate the need for compliance; it shifts the practical focus to following the referenced FAA AD and ensuring documentation and approvals are in order.

In sum, the AD creates a mandatory compliance obligation by reference but does not itself set out enforcement or penalty mechanisms in the reproduced text; it does, however, point to FAA ADs for the technical and terminating actions and preserves existing AMOCs and exclusions.

This instrument operates primarily by cross-reference to, and incorporation of, FAA airworthiness directives and Boeing service material. The AD expressly requires "the actions as detailed in FAA Emergency AD 2008-24-51" and the amendment deletes the original text to "incorporate the original FAA AD by reference" so as to "facilitate easier cross referencing to FAA AD 2011-18-03 Amdt 39-16785 which details the terminating actions for the requirements of this AD." The AD therefore functions as an Australian regulatory imposition that delegates technical detail to specified FAA documents and Boeing service instructions.

Relationship to Boeing service bulletin:

• The AD’s applicability hinges on whether Boeing ASB 737-28A1206 dated 11 January 2006 "has been accomplished" on the aeroplane. The AD then finds that functional tests conducted in accordance with that service bulletin "are not adequate to detect the incorrect wiring condition." That creates an interaction where the ASB both triggers the AD’s applicability (if implemented) and is identified as insufficient as a sole compliance measure.

Acceptance of FAA approvals:

• The AD accepts alternative methods of compliance for FAA AD 2008-24-51 that are approved by the FAA as acceptable means of compliance against the CASA AD. This creates a de facto transnational compliance pathway: FAA-approved AMOCs discharge the operator's CASA obligations under this AD insofar as the AMOC relates to AD 2008-24-51. The AD thus sets up a direct compliance link between FAA regulatory actions and CASA obligations for the specified aeroplanes.

Terminating actions and later FAA ADs:

• The AD references FAA AD 2011-18-03 Amdt 39-16785 as the source of terminating actions. By deleting the original AD text and incorporating the FAA AD by reference, CASA is signalling that compliance and termination conditions tracked by the FAA ADs will control the lifecycle of the CASA AD’s obligations.

Continuity with prior domestic approvals:

• The AD preserves any exclusion or alternate method of compliance that was in force before the amendment came into effect. This means that specific domestic regulatory approvals, exclusions or AMOCs previously granted are not automatically displaced by the amendment. The AD therefore layers the FAA-based compliance model atop existing Australian administrative arrangements without negating those prior domestic permissions.

What the AD does not do in terms of interaction:

• The text provided does not expressly reference any other Australian statutes, regulations or penalty schemes, nor does it reference broader administrative law remedies, judicial review, or appeals processes. It also does not set out how CASA will coordinate inspections or enforcement related to the AD, nor does it specify whether CASA will require reporting of compliance that matches FAA reporting.

Operational implication for cross-border operators:

• For operators that are subject to both Australian and US oversight (for example, aircraft operated by Australian entities but maintained according to Boeing ASBs and FAA ADs), the AD creates an alignment: CASA requires FAA AD compliance in the Australian regulatory context and accepts FAA AMOCs. This reduces the need for operators to obtain separate, differing technical approvals from CASA if they already have FAA approvals that relate to the referenced FAA AD.

In sum, the AD is a domestic instrument that imports technical detail and compliance pathways from FAA ADs and Boeing service information, preserves pre-existing domestic AMOCs, and explicitly accepts FAA-approved AMOCs as discharging CASA obligations under this AD.

The AD contains explicit amendment history points in the text. The original issue of AD/B737/347 became effective on 20 November 2008. The current instrument is labelled AD/B737/347 Amdt 1 and this amendment "becomes effective on 30 September 2011." The amendment deletes the original text of the AD and incorporates the original FAA AD by reference; the stated purpose of that deletion and incorporation is to "facilitate easier cross referencing to FAA AD 2011-18-03 Amdt 39-16785 which details the terminating actions for the requirements of this AD." In other words, the amendment replaces the standalone AD content with a version that operates by reference to FAA AD material and associated terminating actions.

The AD also states that "Despite the new AD/B737/347 Amdt 1, an exclusion or an alternate method of compliance that was in force before the coming into effect of AD/B737/347 Amdt 1 continues to be in force." That provision explicitly preserves pre-existing regulatory arrangements and is an important continuity clause in the amendment history.

Relevant dates and documents in the amendment history:

• Boeing Alert Service Bulletin (ASB) 737-28A1206 dated 11 January 2006 is the service documentation whose accomplishment triggers applicability for the AD.
• The original AD became effective on 20 November 2008 (the AD text states "The original issue of this AD became effective on 20 November 2008").
• The amendment, AD/B737/347 Amdt 1, became effective on 30 September 2011 (the AD text states "This Amendment becomes effective on 30 September 2011").
• The amendment incorporates FAA ADs by reference, specifically FAA Emergency AD 2008-24-51 for the required corrective actions and FAA AD 2011-18-03 Amdt 39-16785 for terminating actions.

Administrative rationale for the amendment:

• The amendment deletes the original AD text and incorporates the original FAA AD by reference "to facilitate easier cross referencing" to the FAA AD that details terminating actions. This indicates an administrative decision to harmonise the CASA AD with the FAA's subsequent rulemaking and corrective-action sequence.

Continuity and approvals:

• The amendment explicitly preserves earlier exclusions and alternate methods of compliance, and it confirms acceptance of FAA-approved AMOCs as a means of compliance with the CASA AD. The amendment therefore modifies the AD's form and provenance (from a standalone CASA text to one that mainly operates by reference) while preserving certain previously approved domestic arrangements.

Signature and formalisation:

• The circulated AD text carries the name and office of the issuer ("Mike Higgins, Delegate of the Civil Aviation Safety Authority") and a date stamp of 5 September 2011, consistent with the stated effective date of 30 September 2011. The document header lists the AD number and amendment (AD/B737/347 Amdt 1) and records "18/2011" as another time/identifying marker.

No further subsequent amendments, revocations, or replacing instruments are mentioned in the supplied text. The amendment history in the document is therefore limited to the original issuance (effective 20 November 2008) and the 2011 amendment (effective 30 September 2011) that replaced the original domestic text with incorporation by reference to FAA ADs and clarified acceptance of FAA-approved AMOCs and preservation of prior exclusions.

The supplied AD text does not include or refer to any litigation history. There are no judicial decisions, administrative appeals, or enforcement proceedings referenced in the document, and no cases are cited. The AD is a regulatory instrument containing applicability, requirement and background material, together with administrative statements about incorporation by reference and preservation of prior AMOCs; it does not include any account of legal challenges, court interpretations, or precedent.

Implications for practitioners assessing litigation risk:

• Because the AD contains no litigation history, there is no text-based record within this document of prior contested interpretations or judicial findings concerning the AD’s scope, the adequacy of the corrective actions, or enforcement steps. Practitioners must therefore rely on the AD’s language itself, the FAA ADs it incorporates (FAA Emergency AD 2008-24-51 and FAA AD 2011-18-03 Amdt 39-16785), and any separate jurisprudence or regulatory records that are outside the text provided here if they wish to understand how courts or tribunals have treated similar directives. The AD does not report any prior disputes or settlements.

Consequential considerations:

• In the absence of reported litigation within the AD, operators and their legal advisers should be attentive to record-keeping, AMOC approvals, and documentary evidence of compliance with the FAA AD text incorporated by reference, because those materials will be the operative technical and procedural source if enforcement or dispute later arises. The AD’s explicit preservation of previously approved exclusions and AMOCs is a potential locus of administrative review or challenge if CASA later questions the validity or applicability of a prior AMOC, but the AD’s text does not narrate any such instances.

Documentation to preserve:

• Given the AD binds operators to actions in FAA AD 2008-24-51 and references terminating actions in FAA AD 2011-18-03, parties seeking to limit future enforcement or litigation risk should preserve documentation demonstrating the applicability of any pre-existing AMOC, FAA approvals relied upon, and records that the FAA-prescribed corrections were performed as required. The AD text itself does not create or describe any appeals mechanism or dispute resolution procedure.

In short, there is no litigation history recited in the AD; respondents must look beyond this document to any external jurisprudence or enforcement records for insights into contested implementation or legal outcomes.

The AD contains several technical and administrative features that can create practical pitfalls for operators and maintenance providers. These are matters grounded in the AD text and should be treated as points of operational attention.

Narrow applicability that can be overlooked:

• The AD applies only to Model 737-600, -700, -700C, -800 and -900 series aeroplanes on which Boeing ASB 737-28A1206 dated 11 January 2006 "has been accomplished." Operators often assume ADs apply broadly by model; here the trigger is the combination of model plus a specific prior accomplishment. Failure to verify whether the ASB work has been performed on a particular airframe could lead to unnecessary work or, conversely, to missed applicability where the ASB was indeed done.

Functional tests in the ASB are insufficient:

• The AD explicitly states "Functional tests conducted in accordance with that service bulletin are not adequate to detect the incorrect wiring condition." Relying on prior ASB functional testing as proof that wiring is correct is therefore a potential compliance failure. Operators must follow the FAA Emergency AD's prescribed inspections/tests rather than assuming the ASB work is sufficient.

Cockpit indications can mislead the crew:

• The failure mode includes a misleading indication in which "The low-pressure lights turn off, incorrectly indicating to the flightcrew that power to both pumps has been removed." This is a human-factors gotcha: crews switching pumps off manually may receive false assurance that both pumps have ceased running. The AD is driven by incidents where the left-hand pump remained energised despite being selected off. Operational procedures that rely on lamp indications without redundancy could be affected.

Preservation of prior exclusions and AMOCs:

• The AD preserves exclusions or AMOCs that were in force before the amendment. That is helpful, but it is also a potential compliance trap if documentation proving an AMOC is missing or ambiguous. Operators relying on pre-existing AMOCs should ensure the approval paperwork is current and accessible, because the AD affirms their continuation but does not re-document them.

Acceptance of FAA AMOCs:

• The AD accepts FAA-approved AMOCs for FAA AD 2008-24-51 as acceptable for the CASA AD. However, an operator relying on an FAA AMOC must ensure the AMOC exactly addresses the FAA AD referenced and that the approval is current and applicable to the specific aeroplane. Assuming acceptance without verifying the AMOC’s scope could be problematic.

Terminating actions reside in another instrument:

• The AD deletes the original text and incorporates FAA AD 2011-18-03 for terminating actions. This means termination of the CASA AD obligations depends on satisfying conditions in an FAA AD. Operators must consult the FAA AD (2011-18-03) to determine how to obtain terminating relief; failing to do so could leave an operator uncertain about when obligations cease.

Compliance date continuity:

• The AD "Compliance: Date remains unchanged to that detailed in the original issue of this directive." Operators must therefore identify the original AD’s compliance date (the original issue became effective 20 November 2008) and ensure they meet the original deadline. The amendment itself does not provide a fresh compliance timetable so there is a risk of confusion if the original date is not clearly recorded.

Document cross-referencing risk:

• Because the AD operates by cross-reference to FAA ADs and a Boeing ASB, there is a practical risk of misreading or missing an instruction buried in the referenced documents. Operators must ensure they read and apply FAA Emergency AD 2008-24-51, FAA AD 2011-18-03 where terminating actions are described, and Boeing ASB 737-28A1206 to understand the ASB work that triggers applicability and why the ASB's functional tests are inadequate.

Record-keeping and proof of compliance:

• The AD is silent on reporting procedures or on the form of compliance records to be lodged with CASA. Operators should therefore treat the AD’s obligations as requiring robust documented proof that FAA AD actions were carried out, and that any AMOCs relied on are properly authorised and applicable.

Image and document completeness:

• The supplied AD includes an embedded image reference ("image.001.png") and administrative metadata. Practitioners should ensure they consult the complete AD package and the referenced FAA documents, not only this AD extract, to avoid missing illustrations, diagrams, or detailed procedural steps contained in the references.

In short, the primary gotchas are: narrow applicability tied to specific Boeing ASB accomplishment; the insufficiency of ASB functional tests; misleading cockpit indications; dependence on FAA documents for corrective and terminating actions; reliance on proper documentation of AMOCs or exclusions; and the need for careful cross-referencing and record-keeping.

The AD prescribes compliance principally by reference: operators must "Perform the actions as detailed in FAA Emergency AD 2008-24-51." The following steps summarise the actions, compliance pathways and administrative steps that the AD establishes or implies, grounded in the AD text.

1. Identify affected aeroplanes

• Confirm whether each aeroplane in your fleet is a Model 737-600, -700, -700C, -800 or -900 series aeroplane.
• Verify whether Boeing Alert Service Bulletin (ASB) 737-28A1206 dated 11 January 2006 "has been accomplished" on the airframe. The AD's applicability attaches only where both conditions are met.

2. Consult the operative FAA AD

• Obtain and carefully read FAA Emergency AD 2008-24-51. The CASA AD makes that FAA AD the source of the required remedial actions. The FAA AD will contain the precise inspection, test, repair and retrofit steps, any part numbers, compliance intervals and workmanship standards to be followed.

3. Implement the FAA-prescribed corrective actions

• Carry out the inspections, tests and wiring corrections set out in FAA Emergency AD 2008-24-51 on each applicable aeroplane. The CASA AD notes that functional tests in Boeing ASB 737-28A1206 are not adequate to detect the incorrect wiring condition, so do not rely exclusively on the ASB functional tests.

4. Record and document compliance

• Maintain complete records demonstrating the FAA AD actions were performed, including dates, work orders, parts used, signed maintenance release, and any test/readings showing corrected wiring and functional verification.

5. Reliance on AMOCs or exclusions

• If you have an exclusion or alternate method of compliance that was in force before 30 September 2011, ensure that documentation demonstrating that approval is available, since the AD explicitly allows those to continue in force.
• If you intend to rely on an FAA-approved AMOC relevant to FAA AD 2008-24-51, confirm that the AMOC is specifically approved by the FAA for that AD and document the approval, because the AD accepts FAA-approved AMOCs as an acceptable means of compliance with the CASA AD.

6. Terminating actions

• If you seek to utilise terminating action provisions, consult FAA AD 2011-18-03 Amdt 39-16785, which the AD incorporates by reference for terminating actions. Ensure the airframe meets the conditions for termination and document how terminating criteria were satisfied.

7. Compliance timing

• The AD states that the compliance date "remains unchanged to that detailed in the original issue of this directive," and notes the original issue became effective on 20 November 2008. Verify the original compliance deadlines and ensure work is completed within the applicable time window. The AD does not provide a new compliance date in the text provided.

8. Coordination with maintenance providers and Boeing

• Coordinate with the aircraft manufacturer and approved maintenance organisations to obtain the specific wiring diagrams, service instructions and tests required by the FAA AD. Because the AD finds the ASB functional test inadequate for detecting the wiring fault, confirm with maintenance providers that the FAA-prescribed inspections (e.g. detailed wiring continuity checks or corrective rewiring) are being implemented.

9. Internal operational measures

• Inform flightcrew and operations personnel of the failure mode described in the AD: manual switching to "OFF" can result in the left-hand pump remaining energised while indications appear to show both pumps off. While the AD mandates corrective technical action, operational awareness and interim mitigations (if any) should be documented until the wiring is fixed.

10. Maintain a compliance audit trail

• Keep copies of the FAA ADs referenced (Emergency AD 2008-24-51 and FAA AD 2011-18-03 Amdt 39-16785), Boeing ASB 737-28A1206, records of work performed, AMOC approvals (FAA or pre-existing domestic approvals), and internal compliance checklists. Because the CASA AD is by incorporation, the FAA and Boeing documents govern the technical content; retaining them with your compliance records demonstrates the link between CASA's directive and the remedial steps taken.

11. Seek clarification where necessary

• If there is uncertainty whether an FAA AMOC applies, whether a pre-existing exclusion remains valid, or how to satisfy terminating action criteria, seek formal clarification from the FAA (for AMOC approvals) and document that correspondence. The AD explicitly accepts FAA-approved AMOCs, so obtaining and preserving FAA approval documentation is a practicable compliance strategy.

12. Note effective date and continuity

• The AD became effective 30 September 2011 and preserves prior AMOCs that were in force before that date. Confirm whether any previous approvals you rely on were indeed in place before the amendment's effective date.

In practice, complying with this AD means using the FAA Emergency AD 2008-24-51 and associated FAA and Boeing documents as the operative technical manual for corrective action, keeping careful records and ensuring any AMOCs or exclusions are properly documented and traceable to their approving authority.