AD/B737/359 - Outboard Landing Light Wire Bundles

This Directive organises its technical obligations around three core concepts: identification and scope, conditional options for interim mitigations, and mandatory replacement plus inspection with specific timing requirements.

Identification and scope. The Applicability clause defines which aeroplanes fall within the AD: Model 737-100, -200, -200C, -300, -400 and -500 series aeroplanes as identified in Boeing SB 737-28-1241, Revision 1, dated 31 August 2007. The SB reference is part of the identification mechanism; the Directive does not list individual serial numbers in the provided text, so compliance is triggered by a match to the SB identification. The AD also specifies particular subsets (Model 737-300/-400/-500) for Requirement 1, tied to ASB 737-33A1140 dated 22 May 2006.

Conditional interim mitigations. For the specified 737-300/400/500 subset, operators may elect one of two actions: deactivate the outboard landing lights by following Part 1 of ASB 737-33A1140, or modify the wiring by following Part 2 of that ASB (Requirement 1). This creates a short-term compliance choice that affects operational capability. The Directive explicitly notes an operational limitation tied to that choice: the Master Minimum Equipment List prohibits night dispatch with deactivated outboard landing lights if an inboard landing light fails; and if an operator chooses deactivation under Part 1 of the ASB, "there is no MMEL relief allowing for this configuration for night operations should any inboard landing light fail" (Note 1). The Directive therefore combines a technical mitigation option with a cross-reference to operational dispatch rules.

Mandatory replacement and inspection. Requirement 2 imposes a longer-term mandatory programme for all aeroplanes in scope. This includes replacement of the landing lights and fuel shutoff valve wire bundles with redesigned bundles and execution of related investigative/other specified and corrective actions, a detailed inspection for fairleads, grommets and chafed wires in the four electrical junction boxes in the main wheel well with corrective actions, and replacement of electrical connectors and backshell clamps with improved parts where applicable. The Directive makes clear that certain corrective actions must be done "before further flight after the replacement" or after the inspection (Requirement 2 wording).

Timing and termination links. The Directive sets two compliance windows: Requirement 1 within 180 days, Requirement 2 within 60 months. It further states that, for Model 737-300, -400 and -500 aeroplanes identified in ASB 737-33A1140, accomplishing the applicable Requirement 2 actions terminates the Requirement 1 actions. Thus Requirement 2 is the long-term fix that, once implemented, supersedes the interim options in Requirement 1.

Acceptable prior compliance and AMOC. The AD accepts actions accomplished before its effective date in accordance with earlier SB and ASB revisions, in particular SB 737-28-1241 dated 7 April 2006 and Part 2 of SB 737-28-1241 where applicable. It also states that later revisions of the listed SBs, once approved by the FAA as an AMOC to FAA AD 2009-14-04, are acceptable for compliance with the equivalent Requirements of this Directive (text under Requirements). The AD explicitly refers to FAA AD 2009-14-04 (Note 2), integrating international certification documentation into its compliance framework.

Hazard rationale. The background sets out the safety hazard the Directive addresses: reports of uncommanded engine shutdowns, burned and damaged wire bundles associated with the outboard landing lights and engine fuel shutoff valves, and the risk of a hot short between those circuits that could lead to uncommanded engine shutdown (Background). The technical measures,wiring redesign, connector and clamp upgrades, and inspection/correction of chafed wiring and damaged fittings,are linked mechanically to preventing overheating, chafing and electrical shorting in the affected circuits.

Operators of the identified Boeing 737 series aeroplanes bear the direct obligations under the Directive. The Applicability clause lists Model 737-100, -200, -200C, -300, -400 and -500 series aeroplanes as identified in Boeing SB 737-28-1241, Revision 1, dated 31 August 2007, and Requirement 1 specifically addresses Model 737-300, -400 and -500 aeroplanes identified in ASB 737-33A1140 dated 22 May 2006. Therefore the immediate legal addressees are operators who possess aeroplanes that match those SB identifications.

Maintenance organisations and certificated engineers who perform modifications and inspections are operationally affected because the Directive mandates technical actions that must be accomplished in accordance with the specified Boeing Service Bulletins and Alert Service Bulletins (Requirements). Those organisations must ensure that the replacement of wire bundles, inspections, fitment of improved connectors and clamps, and associated investigative and corrective actions are performed to the standard required by the SBs and the AD, and that specified corrective actions that arise from inspections are completed prior to further flight (Requirement 2 mandates corrective actions "before further flight after the replacement" and for the inspection corrective actions).

Flight operations and dispatch planners are indirectly affected by the availability consequences of some compliance choices. Note 1 warns that deactivating the outboard landing lights under Part 1 of ASB 737-33A1140 does not create any MMEL relief for night operations if an inboard landing light fails. Operators who choose deactivation therefore face operational constraints when planning night dispatches and must adhere to MMEL restrictions.

Regulatory decision-makers and approval authorities are implicated by the AD’s acceptance of alternative compliance methods and prior actions. The AD accepts actions accomplished before the effective date under certain SB revisions and allows later SB revisions approved by the FAA as an AMOC to FAA AD 2009-14-04 to be acceptable for compliance with the equivalent Requirements. This creates a set of interlocking approvals that maintenance organisations and operators must monitor and, where relevant, seek or rely upon FAA AMOC approvals (text under Requirements and Note 2).

Aircraft owners and lessors are affected through asset management choices. An aircraft subject to these requirements cannot be operated indefinitely without compliance; compliance choices (deactivation versus wiring modification) have different operational consequences and may also affect maintenance scheduling and asset availability. Although the AD does not spell out commercial consequences, it places a maintenance obligation on the aircraft which owners, lessors and their technical managers must satisfy.

Finally, the Civil Aviation Safety Authority (CASA), represented here by its delegate James Coyne who issued the Directive, is the issuing authority; the AD sets compliance timeframes and accepts specific SB revisions and FAA approvals. The Directive text provides the legal instrument and identifies the issuing delegate and date (James Coyne, Delegate of the Civil Aviation Safety Authority, 15 July 2009).

Key duties

• Identify applicability. Operators must determine whether their aeroplanes match the models and SB identifications listed in the Applicability clause: Model 737-100, -200, -200C, -300, -400 and -500 series aeroplanes as identified in Boeing SB 737-28-1241, Revision 1, dated 31 August 2007. The Directive's obligations attach to aeroplanes so identified.

• For Model 737-300, -400 and -500 (as specified) choose and accomplish one of two actions within 180 days. Requirement 1 requires operators of the identified Model 737-300/-400/-500 aeroplanes to either: deactivate the outboard landing lights by following Part 1 of ASB 737-33A1140, or modify the wiring to the outboard landing lights by following Part 2 of that ASB. The compliance period for Requirement 1 is "Within 180 days after the effective date of this Directive" (Compliance).

• For all applicable aeroplanes accomplish Requirement 2 within 60 months. Requirement 2 requires three main actions to be completed in accordance with SB 737-28-1241, Revision 1: (a) replace the wire bundles for the landing lights and fuel shutoff valves with redesigned wire bundles and carry out related investigative, other specified, together with corrective actions as applicable, with those actions done "before further flight after the replacement"; (b) carry out a detailed inspection for broken/damaged/missing fairleads, grommets and chafed wires in the four electrical junction boxes of the main wheel well and do applicable corrective actions "before further flight after the inspection"; (c) replace electrical connectors and backshell clamps with new, improved parts "as applicable". Compliance time for Requirement 2 is "Within 60 months after the effective date of this Directive" (Compliance).

• Ensure corrective actions that arise from replacement or inspection are completed prior to further flight. The Directive explicitly makes corrective actions arising from Requirement 2.a and 2.b a pre-flight requirement after those specific tasks (Requirement 2 text).

• When Requirement 2 is accomplished for Model 737-300, -400 and -500 identified in ASB 737-33A1140, it terminates Requirement 1 actions for those aeroplanes. That is, the long-term fix in Requirement 2 supersedes the interim options of Requirement 1 for those models.

• Maintain records and evidence of compliance. The Directive accepts prior actions that were accomplished before the effective date if done in accordance with earlier SB or ASB revisions referenced in the AD. Accordingly, operators must retain documentation showing compliance with the accepted SBs if relying on prior work.

Key rights / flexibilities

• Choice of interim mitigation. Operators of affected 737-300/-400/-500 aeroplanes have the right to choose between deactivating the outboard landing lights (Part 1 of the ASB) or implementing a wiring modification (Part 2), at least for the initial 180-day compliance window (Requirement 1).

• Acceptance of prior work. The AD recognises work completed before the AD’s effective date under SB 737-28-1241 dated 7 April 2006 or Part 2 of SB 737-28-1241 as acceptable for compliance with the relevant Requirement 2 actions. Operators who completed those actions before the AD's effective date may rely on that work for compliance.

• AMOC pathway. The AD allows the use of later revisions of the referenced Boeing SBs provided they are approved by the FAA as an Alternate Method of Compliance to FAA AD 2009-14-04. That creates a formal pathway to accept updated Boeing documentation when the FAA approves it.

• No automatic MMEL relief. While not a right in the positive sense, the Directive plainly notifies operators that choosing deactivation under Part 1 does not create MMEL relief for night operations where inboard lights may fail. This is a rule-like constraint that affects operators’ operational rights; it is explicit in Note 1.

Duty timing, sequencing and termination. The Directive specifies two distinct timeframes (180 days for Requirement 1, 60 months for Requirement 2) and requires some corrective actions to be completed prior to further flight after the specified maintenance or inspection steps. For the Model 737-300/-400/-500 subset, compliance with Requirement 2 constitutes termination of Requirement 1 obligations. These sequencing rules create operational and maintenance planning obligations for operators.

Delegated authority. The Directive is issued by the Delegate of the Civil Aviation Safety Authority, James Coyne (signature and date appear at the end of the AD). The AD references FAA AD 2009-14-04 and allows acceptance of FAA-approved AMOC actions, situating CASA’s directive within a framework that recognises certain FAA approvals for equivalence.

The text of AD/B737/359 as provided does not specify civil penalties, criminal sanctions, or the precise enforcement procedures for failure to comply. The Directive sets mandatory technical requirements, compliance deadlines and conditions, but it does not contain penalty provisions, compliance audit mechanisms, or enforcement steps in the supplied text. The AD does however set mandatory actions and effective date specifics (it "becomes effective on 27 August 2009") which are typical features of enforceable regulatory instruments.

What is explicit in the AD about enforceable actions are the specified technical obligations and the times within which they must be undertaken: Requirement 1 must be accomplished "within 180 days after the effective date of this Directive" and Requirement 2 "within 60 months after the effective date" (Compliance). Certain corrective actions are mandated to be completed "before further flight after the replacement" or "before further flight after the inspection" (Requirement 2). These pre-flight conditions create immediate operational constraints following inspection or replacement activities.

The Directive makes administrative acceptance statements. It recognises prior compliance carried out in accordance with earlier SBs (SB 737-28-1241 dated 7 April 2006 and Part 2 of SB 737-28-1241) as acceptable for compliance with Requirement 2, and it accepts later SB revisions that the FAA approves as an AMOC to FAA AD 2009-14-04. These acceptance clauses create administrative pathways for what will be treated as compliant work, which is relevant to enforcement insofar as an inspection or regulator will treat such prior work as satisfying the AD.

Because the AD text does not itself state enforcement procedures or penalties, readers relying on the Directive should be aware that enforcement mechanisms and penalties would be found in the broader regulatory framework under which CASA issues ADs, and in the aviation safety regulatory statutes, regulations and enforcement policies that govern CASA’s operations. The AD documents the mandatory technical requirements and compliance schedule; the provided text does not describe the consequences of non-compliance or the procedures by which compliance will be verified or enforced.

Operators should therefore plan compliance on the assumption that failure to meet the AD’s explicit technical and timing requirements could have regulatory consequences under the applicable aviation safety laws and that proof of compliance will be necessary. The AD itself establishes what must be done and when, and declares acceptable prior actions and AMOC pathways. The AD bears the signature line of James Coyne, Delegate of the Civil Aviation Safety Authority, dated 15 July 2009, and an explicit effective date of 27 August 2009, which formalise its status as an issued Directive.

The Directive explicitly cross-references other regulatory and technical instruments, creating interaction points with operational rules and international certification instruments.

FAA AD 2009-14-04. The AD cites FAA AD 2009-14-04 (Note 2: "FAA AD 2009-14-04 Amdt 39-15954 refers") and states that later revisions of the listed Boeing Service Bulletins, when approved by the United States Federal Aviation Administration as an Alternate Method of Compliance to FAA AD 2009-14-04, are acceptable for compliance with the equivalent Requirements of this Directive. This establishes a formal reliance on FAA assessment and AMOC approvals as an accepted pathway for compliance under the CASA AD. Consequently, FAA determinations on AMOCs to FAA AD 2009-14-04 can have direct application to compliance with this Directive per the AD text.

Boeing Service Bulletins and Alert Service Bulletins. The AD anchors its technical requirements to specific Boeing SB and ASB documents,SB 737-28-1241 Revision 1 (31 August 2007), ASB 737-33A1140 (22 May 2006) and an earlier SB 737-28-1241 dated 7 April 2006. The AD accepts actions completed in accordance with those earlier SB revisions as acceptable for compliance with Requirement 2 for certain groups and parts. Therefore, the AD is operating through a classic service-bulletin compliance mechanism: the SBs and ASBs specify the technical steps; the AD mandates and sets timelines for those steps. Changes to the SBs that are subsequently FAA-approved as AMOCs are also incorporated by reference as acceptable methods for compliance.

Master Minimum Equipment List (MMEL) interaction. The AD specifically warns that the MMEL prohibits dispatch for night operations with deactivated outboard landing lights in the event that either of the inboard landing lights fails, and notes that if outboard landing lights are deactivated pursuant to Part 1 of ASB 737-33A1140, "there is no MMEL relief allowing for this configuration for night operations should any inboard landing light fail" (Note 1). This creates a direct operational interaction between the AD’s maintenance/alteration choices and the MMEL-based dispatch rules that govern airworthiness dispatchability.

Pre-existing compliance actions. The AD accepts actions accomplished before the effective date in accordance with SB 737-28-1241 dated 7 April 2006 and Part 2 of SB 737-28-1241 as acceptable for compliance with Requirement 2 or Requirement 2.b respectively. This creates a grandfathering interaction with prior technical work done under earlier SBs. Operators who have undertaken those earlier SB actions can rely on them under the AD.

International regulatory recognition. By referencing FAA AD 2009-14-04 and accepting FAA-approved AMOCs, the Directive installs a mechanism for recognising international regulatory decisions. It does not, in the provided text, reference other international authorities, but the FAA linkage is explicit.

Operational rules and airworthiness documentation. The AD’s Note 1 explicitly references the MMEL. Because MMELs are operational airworthiness documents that determine what equipment failures permit dispatch under specified conditions, the AD’s note shapes operational outcomes depending on whether an operator elects deactivation as an interim option. Operators must reconcile their maintenance modifications under the AD with the MMEL and dispatch rules, as the AD sets a maintenance state that will alter dispatch eligibility.

Procedurally, the AD sets technical obligations which must be performed "in accordance with" the specified SBs and ASBs, and it sets pre-flight corrective requirements. The acceptance of earlier SB-compliant work and FAA-approved AMOCs creates administrative links for demonstrating compliance that bridge service bulletin work, FAA approvals and the CASA AD. Those are the explicit interactions contained within the AD text.

The text of AD/B737/359 provided here contains only the issued Directive as of the dates shown in the document. The AD cites underlying Boeing Service Bulletins and an FAA Airworthiness Directive and notes acceptances for prior work and FAA AMOCs, but it does not itself show an amendment record within the supplied text.

What the AD does record about prior or alternative documentation is as follows:

• It identifies SB 737-28-1241, Revision 1, dated 31 August 2007, as the SB that identifies the aeroplanes within the Applicability clause.

• It recognises that for aeroplanes identified as Groups 1 and 2 in SB 737-28-1241, Revision 1, "Actions accomplished before the effective date of this Directive in accordance with SB 737-28-1241, dated 7 April 2006, are acceptable for compliance with Requirement 2." That language accepts an older SB, dated 7 April 2006, for prior compliance.

• It states that "For all aeroplanes - Actions accomplished before the effective date of this Directive in accordance with Part 2 of the Accomplishment Instructions of SB 737-28-1241 are acceptable for compliance with Requirement 2.b." That again recognises certain pre-existing work.

• It states that "Later revisions of the above SBs, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2009-14-04 are considered acceptable for compliance with the equivalent Requirements of this Directive." This provides a mechanism to accept later revisions of the SBs when accompanied by FAA AMOC approval.

• The AD explicitly refers to FAA AD 2009-14-04 Amdt 39-15954.

Beyond the acceptances and references cited above, the AD text does not list any subsequent amendments to the AD itself, nor does it include revision history lines for the Directive. The effective date stated in the AD is 27 August 2009 and the issuance signature is dated 15 July 2009, signed by James Coyne, Delegate of the Civil Aviation Safety Authority. The AD identification (AD/B737/359) and title appear repeatedly and the AD date is 9/2009, but the provided text does not show any later amendment entries or supersessions.

If amendment history beyond what is contained in this AD is required, that information is not present in the supplied document. The AD does, however, create an administrative pathway to accept later SB revisions once those revisions are approved by the FAA as AMOCs to the FAA AD; that mechanism effectively anticipates changes in the referenced SBs and sets a condition under which the AD will accept subsequent SB amendments.

The supplied text of AD/B737/359 contains no litigation history. It comprises the Directive’s operative text, applicability, requirements, compliance timeframes, notes and background, and the signature of the CASA delegate. There are no references in the document to appeals, stays, judicial review, administrative challenges, or court decisions. The AD does not report any disputes, legal proceedings, or litigation outcomes concerning this Directive within the provided material.

Accordingly, there is no litigation history recorded in the source document for this AD. Users who require litigation or challenge history would need to consult external legal databases, administrative records or CASA's public records for any subsequent proceedings or challenges that may have arisen after the issuance of this Directive. The AD as presented stands as a regulatory instrument with no internal record of legal contests.

This AD contains a number of specific operational and compliance traps that are explicitly set out in the text or arise directly from the sequencing and cross-references in the Directive. These are practical points that an operator, maintenance manager or compliance officer should note to avoid inadvertent non-compliance or operational disruption.

1. Choice of interim action has operational consequences, and no MMEL relief is provided. Requirement 1 allows deactivation of outboard landing lights (Part 1 of ASB 737-33A1140) as an option, but Note 1 warns that the MMEL "prohibits dispatching an aeroplane for night operations with deactivated outboard landing lights in the event that either of the inboard landing lights fail" and that if outboard lights are deactivated under Part 1 "there is no MMEL relief allowing for this configuration for night operations should any inboard landing light fail." This means electing deactivation may restrict night dispatch capability without an MMEL relief path.

2. Some corrective actions must be done before further flight. Requirement 2.a and 2.b specify that the related investigative, other specified and corrective actions after replacement, and the corrective actions after the detailed inspection, "must be done before further flight". That creates immediate re-entry-to-service conditions: replacement or inspection alone, without completion of corrective steps, will not permit further flight. Operators must plan for potential extended ground time if inspections uncover corrective work.

3. Termination link between Requirement 1 and Requirement 2 for certain models. For 737-300, -400 and -500 series identified in ASB 737-33A1140, accomplishing Requirement 2 actions terminates Requirement 1 actions. Operators should not treat Requirement 1 as a permanent cure; it is an interim pathway that is superseded upon completion of the long-term fix required under Requirement 2.

4. Prior work acceptance is limited and contextual. The AD accepts actions completed before the effective date under SB 737-28-1241 dated 7 April 2006 for Groups 1 and 2 and accepts Part 2 work done before the effective date as satisfying Requirement 2.b. However, the acceptance is explicitly limited to those prior SB revisions and to works that align with the AD’s specific language. Operators relying on prior work must have documentation proving that the earlier SB work matches the AD’s scope.

5. AMOC reliance introduces dependency on FAA approvals. The AD accepts later SB revisions only when the FAA approves them as an AMOC to FAA AD 2009-14-04. If an operator intends to use a later SB revision as the compliance method, the operator must verify that the FAA has granted the necessary AMOC. That introduces an inter-authority dependency that may complicate rapid adoption of newer SB revisions.

6. Applicability defined by SB identification. The Applicability clause ties the AD to models "as identified in Boeing Service Bulletin (SB) 737-28-1241, Revision 1, dated 31 August 2007." Compliance therefore begins with correctly identifying whether a specific aircraft is included based on the SB identification. Misidentification could lead to either unnecessary work or unintended non-compliance.

7. Different timeframes for different tasks. Requirement 1 must be done within 180 days while Requirement 2 must be done within 60 months. These differing windows require separate planning tracks: short-term interim action for some models and longer-term systemic replacement for all affected aeroplanes.

8. Multiple technical actions and sequencing. Requirement 2 bundles three distinct technical obligations: wire bundle replacement and follow-up corrective actions, a detailed inspection of four electrical junction boxes with corrective actions, and replacement of connectors and clamps as applicable. Operators must track each subtask and the "before further flight" sequencing where specified.

9. No penalties or enforcement mechanisms stated in the text. The AD does not set out enforcement measures or penalties in the provided document. Operators cannot rely on the absence of explicit penalties in this AD; they must nevertheless treat the AD as an issued safety directive with mandatory compliance timelines that interact with the broader aviation regulatory enforcement regime.

10. Documentation burden. To rely on prior work or FAA AMOCs, operators must retain and be able to present records showing that the earlier SB work or later SB revisions have the requisite FAA AMOC approvals. The AD’s acceptance clauses place an evidential burden on operators that must be anticipated.

Each of these "gotchas" flows directly from the AD text: the MMEL note, the "before further flight" phrasing, the termination of Requirement 1 upon completion of Requirement 2 for specified models, the limited acceptance of prior SB work, the AMOC acceptance condition, the Applicability linkage to a specific SB revision, and the compliance timelines.

The Directive sets out explicit actions and timelines. Compliance requires an operator to follow the specified steps, document them and ensure corrective actions that are stated to be "before further flight" are completed. Below is a practical, source-grounded sequence aligned with the AD text.

1. Determine applicability immediately. Consult Boeing SB 737-28-1241, Revision 1 dated 31 August 2007, and identify whether each aeroplane in your fleet is listed under that SB. The AD's Applicability clause ties the Directive to aeroplanes "as identified in" that SB. For the subset 737-300, -400 and -500, also consult Boeing ASB 737-33A1140 dated 22 May 2006 to confirm identification per Requirement 1.

2. For affected 737-300/-400/-500 aeroplanes: choose an interim action within 180 days. Requirement 1 allows two alternative immediate measures:

   • Option A: Deactivate the outboard landing lights by accomplishing all of the actions specified in Part 1 of ASB 737-33A1140; or
   • Option B: Modify the wiring to the outboard landing lights by accomplishing all of the actions specified in Part 2 of ASB 737-33A1140. Make the operational decision between Option A and Option B within 180 days of the Directive's effective date, bearing in mind Note 1 which makes it explicit that deactivation under Part 1 does not provide MMEL relief for night operations in the event of inboard light failure. Document the chosen action and retain compliance records.

3. Plan and execute Requirement 2 for all applicable aeroplanes within 60 months. Requirement 2 must be accomplished in accordance with SB 737-28-1241, Revision 1, and has three elements:

   • 2.a Replace the wire bundles for the landing lights and fuel shutoff valves with the redesigned wire bundles specified in the SB; carry out the related investigative, other specified, and corrective actions as applicable. The AD requires that the related investigative, other specified and corrective actions "must be done before further flight after the replacement." Ensure that these investigations and corrections are completed and documented prior to returning the aircraft to service after the replacement.
   • 2.b Carry out a detailed inspection for any broken, damaged, or missing fairleads, any damaged or missing grommets and any chafed or damaged wires or wire bundles in the four electrical junction boxes of the main wheel well, and do the applicable corrective actions. These corrective actions "must be done before further flight after the inspection." Include the four junction boxes in your inspection plan and prepare for immediate remedial work if defects are found.
   • 2.c Replace the electrical connectors and backshell clamps with new, improved electrical connectors and backshell clamps, "as applicable." Determine applicability per the SB and schedule replacement where required.

4. Coordinate sequencing and ensure pre-flight corrective completion. The AD explicitly makes corrective actions arising from the replacement and the inspection pre-flight requirements. Plan maintenance events and parts provisioning to ensure that if the inspection or replacement uncovers required corrective work, the aircraft will not be released to service before those corrections are made. This will reduce the risk of unscheduled ground time and regulatory non-compliance.

5. Confirm termination of Requirement 1 where appropriate. For Model 737-300, -400 and -500 aeroplanes identified in ASB 737-33A1140, accomplishing the applicable Requirement 2 actions will terminate the Requirement 1 obligations for those aircraft. Record the completion of Requirement 2 and maintain records evidencing that Requirement 1 is thereby terminated for those aircraft.

6. Check for acceptable prior work. If any of the required actions were completed before the effective date of the Directive, determine whether they were done in accordance with the SB versions the AD accepts:

   • For Group 1 and 2 aeroplanes in SB 737-28-1241 Revision 1, actions accomplished before the effective date in accordance with SB 737-28-1241 dated 7 April 2006 are acceptable for compliance with Requirement 2.
   • For all aeroplanes, actions accomplished before the effective date in accordance with Part 2 of the Accomplishment Instructions of SB 737-28-1241 are acceptable for compliance with Requirement 2.b. Collate the documentation of any such prior work to present as evidence of compliance.

7. If intending to use later Boeing SB revisions, ensure FAA AMOC approval exists. The AD accepts later SB revisions only when "approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2009-14-04." Before relying on a later SB revision as the basis for compliance, confirm FAA AMOC approval and retain that approval documentation.

8. Record-keeping. Keep maintenance records evidencing the performed actions, parts installed, inspection findings, corrective actions completed, and any FAA AMOC or documentation showing prior compliance under accepted SB versions. These records will be necessary to demonstrate conformity with the Directive.

9. Reconcile with MMEL and operational planning. If the operator elects deactivation of outboard landing lights under Part 1 of the ASB, it must plan flight dispatches recognising that night operations may be constrained if an inboard landing light fails, because the AD states "there is no MMEL relief" for that configuration. Coordinate with flight operations and dispatch to avoid inadvertent dispatch conditions that would violate MMEL rules.

10. Maintain awareness of FAA AD and Boeing documentation. The AD references FAA AD 2009-14-04. Operators should monitor any FAA action regarding that AD and any AMOC approvals, since the AD expressly incorporates FAA-approved AMOCs as acceptable for compliance with this Directive.

In practical terms, compliance requires maintenance planning across two time horizons, immediate operational decisions for certain aircraft and a fleet-wide program of wiring and connector replacements and inspections that must be completed within five years. Each step must be documented, and corrective actions that are designated as pre-flight must be completed prior to returning the aircraft to service.