The AD rests on two core engineering and operational concepts stated in the source text. First, a component failure mode presents a heat-generation hazard: bench testing showed that a failed centre tank fuel transfer shutoff valve can reach temperatures exceeding a fuel hot surface ignition point. That is the causal safety concern explicitly cited in the AD background. Second, the AD implements a combined mitigation strategy that mixes immediate electrical isolation and crew awareness with a hardware replacement programme and operational fuel quantity limits where a secondary design change (fuel vent modification) is not present.

Mechanistic elements in the AD are discrete and prescriptive. The immediate electrical isolation (Requirement 1) involves opening the applicable circuit breakers and installing lock rings on those breakers, to prevent inadvertent reclosure. Requirement 2 then prescribes removal and stowage of the wiring from the opened breakers, again following Bombardier Alert Service Bulletin A601R-28-045 Revision A dated 7 December 2001. These two steps are time-critical: Requirement 1 must be done "within one day after the effective date" and Requirement 2 "within four days" (Compliance section).

The replacement pathway (Requirement 3) is a parts-based correction: operators must determine the installed valve P/Ns and replace any valve with P/N 601R62256-5 with P/N 601R62256-3, with a compliance window of 45 days. Requirement 4 then provides the conditional operational reversal: once verification shows only P/N 601R62256-3 valves are fitted, operators may reconnect the previously isolated circuit breakers and remove the lock rings, returning the electrical control to normal.

Operational allowances are also central. Requirement 5 permits dispatch with the centre tank full and both fuel transfer shutoff valves inoperative (i.e. with the breakers opened per Requirement 1), subject to the limitations in Requirement 6 if they apply. Requirement 5 also imposes a flight crew briefing obligation about fuel indication anomalies and the specific Engine Indicating and Crew Alerting System message "LR XFER SOV" that will be indicated on the ground and may disappear during climb but will remain on for the rest of flight. Requirement 6 requires determination whether the Bombardier fuel vent system modification has been incorporated; if it has not, affected aircraft must operate with less than 200 pounds of fuel in the centre tank, and the AFM limitation section must be amended to reflect that limit.

The AD cross-references manufacturer service documentation (ASB A601R-28-045 Revision A for breaker work and SB 601R-28-024 Revision A for vent system modification status) and a Transport Canada notice (CF-2001-47). The AD contains internal text repetitions and an inconsistency in applicability language (see Gotchas), which carry practical implications for implementation and record-keeping.

The AD identifies several classes of actors with concrete duties or operational consequences.

• Aircraft operators of Bombardier (Canadair) CL-600-2B19 "Regional Jet" aeroplanes. The AD's initial "Applicability" line states "CL-600-2B19 'Regional Jet' aircraft, serial numbers 7003 and subsequent. Requirement: Applicable to all affected aircraft." Elsewhere in the document the AD repeats an applicability statement specifying aircraft with serial numbers 7003 through 7109. Both applicability statements appear in the AD text. Operators whose aircraft fall inside the applicable serial number range(s) must carry out the actions set out in Requirements 1 through 6 and comply with the timelines in the Compliance section.

• Maintenance organisations and licensed maintenance personnel. Requirements 1 and 2 mandate mechanical/electrical actions (opening circuit breakers, installing lock rings, disconnecting and stowing wiring) to be accomplished "in accordance with the Accomplishment Instructions of the Bombardier Alert Service Bulletin (ASB) A601R-28-045 Revision A dated 7 December 2001." Requirement 3 mandates identification and replacement of valve P/Ns; Requirement 4 requires verification and reconnection work where appropriate. These are maintenance tasks that must be performed by appropriately authorised maintenance providers.

• Flight crew and operations personnel. Requirement 5 requires that the flight crew must be briefed about altered fuel indication behaviour and the presence of an EICAS message "LR XFER SOV." The AD expressly permits this briefing to be accomplished by inserting a copy of the AD into the Aircraft Operations Manual. Dispatchers and crew schedulers will be affected because the AD permits operation with inoperative valves but subject to restrictions and briefings.

• Continuing airworthiness and records teams. Requirement 6 requires determination of incorporation of a prior Bombardier service bulletin (SB 601R-28-024 Revision A dated 11 November 1998). If the vent modification has not been incorporated, the AFM limitation section must be amended to reflect a less-than-200-pounds centre tank fuel limit. These are continuing airworthiness documentation and flight manual amendment obligations.

• Parts suppliers and OEM representatives. Requirement 3 prescribes replacement of particular P/Ns (from 601R62256-5 to 601R62256-3). Operators who need replacement valves will interact with suppliers, and maintenance planners will need to secure the correct part numbers.

• Regulators and compliance monitors. The AD is issued under subregulation 39.1(1) of CAR 1998 and was notified in the Commonwealth Gazette. CASA as the issuing authority and any inspectors enforcing CAR compliance are implicated.

The AD text itself imposes timelines and prescriptive procedures; actors outside these categories (e.g. airports, fuel suppliers) are not directly mentioned by the AD. The AD also references Transport Canada CF-2001-47, indicating coordination with the foreign authority, but the AD itself applies to the aircraft and operators named in its applicability statements.

The AD imposes specific duties on operators and does grant a limited operational right. The duties are granular and time-bound.

Duties (by Requirement number and compliance window as stated in the AD):

• Requirement 1: Open and install a lock ring on applicable circuit breakers in accordance with the Accomplishment Instructions of Bombardier ASB A601R-28-045 Revision A dated 7 December 2001. Compliance: within one day after the effective date of this Directive.

• Requirement 2: Disconnect and stow the electrical wires from the circuit breakers opened per Requirement 1, again in accordance with the ASB A601R-28-045 Revision A. Compliance: within four days after the effective date.

• Requirement 3: Determine the P/N of the fuel transfer shutoff valves installed in the centre fuel tank. Replace any valve P/N 601R62256-5 with valve P/N 601R62256-3. Compliance: within 45 days after the effective date.

• Requirement 4: If, as a result of Requirement 3, it is verified that only valves with P/N 601R62256-3 are installed, reconnect the circuit breaker wires that have been disconnected and stowed in accordance with Requirement 2, remove lock rings and reset the associated circuit breakers. Compliance: concurrent with Requirement 3.

• Requirement 5: Dispatch provisions and flight crew briefing obligations. The AD permits operation of affected aircraft with the centre fuel tank full and with both fuel transfer shutoff valves inoperative (i.e. circuit breakers opened per Requirement 1), subject to the restrictions in Requirement 6. The flight crew must be briefed that wing tanks will indicate full until the centre tank is empty and that the Engine Indicating and Crew Alerting System message "LR XFER SOV" will be indicated on the ground and may disappear during climb but will remain on for the remainder of the flight. The AD provides that this briefing may be accomplished by inserting a copy of the Directive into the Aircraft Operations Manual.

• Requirement 6: Determine whether the fuel vent system has been modified in accordance with Bombardier Service Bulletin 601R-28-024 Revision A dated 11 November 1998. Aircraft that have not incorporated the fuel vent system modification must operate with less than 200 pounds of fuel in the centre fuel tank. The AFM limitation section must be amended to reflect the limit. The AD notes that the AFM amendment may be accomplished by inserting a copy of the Directive into the AFM limitation section. Compliance for Requirement 6 is within one day after the effective date until Requirement 4 is accomplished.

Rights and operational allowances:

• The AD explicitly permits dispatch with inoperative fuel transfer shutoff valves under defined conditions. Requirement 5 states that operation is permitted with the centre fuel tank full and with both fuel transfer shutoff valves inoperative provided the breakers are opened per Requirement 1 and subject to any restrictions in Requirement 6. That is an operational right contingent on compliance with the short-term isolation measures and the vent system/AFM restrictions where applicable.

• The AD also provides a conditional right to restore normal circuit breaker function. Requirement 4 allows reconnection of circuit breaker wires, removal of lock rings and resetting of breakers only when it has been verified that only the acceptable valve P/N (601R62256-3) are installed.

Procedural references and documentation obligations:

• For the breaker work and wire stowage, operators must follow Bombardier ASB A601R-28-045 Revision A dated 7 December 2001. For the vent system determination, operators must reference Bombardier SB 601R-28-024 Revision A dated 11 November 1998. The AD also references Transport Canada CF-2001-47 as related.

Time-bounded compliance windows are explicit in the Compliance section. The AD becomes effective on 19 December 2001 and sets staggered deadlines: Requirement 1 within one day, Requirement 2 within four days, Requirement 3 within 45 days, Requirement 4 when Requirement 3 is complete, Requirement 5 effective as of the AD date until Requirement 4 is done, and Requirement 6 within one day until Requirement 4 is accomplished.

The AD does not set out penalty provisions within its text. The AD is notified in the Commonwealth Gazette and signed by a CASA delegate on 17 December 2001.

The AD text itself does not specify monetary penalties, administrative sanctions or criminal liability provisions. It is issued under the authority of a CASA delegate pursuant to subregulation 39.1(1) of CAR 1998, and the document is notified in the Commonwealth Gazette, indicating official promulgation. The AD prescribes mandatory actions and compliance windows but contains no clause that sets out enforcement mechanisms or penalty amounts within the AD text provided.

Consequences implicit in the AD structure and modes of issuance:

• Regulatory duty to comply. Because the AD is issued under subregulation 39.1(1) of CAR 1998 and notified in the Gazette, operators named in the Applicability section have an obligation to perform the specified corrective and operational actions within the stated time frames. The AD text frames the required actions as those the delegate "considers necessary to correct the unsafe condition" and specifies that the actions must be taken "in relation to the aircraft or aeronautical product mentioned in the applicability section" and "in accordance with the instructions set out in the requirement section" and "at the time mentioned in the compliance section." That language establishes mandatory compliance expectations.

• Indirect enforcement avenues. The AD references Bombardier ASB and SB documents as the source of accomplishment instructions. Compliance can be verified by maintenance records, AFM amendments, and flight crew briefings. While the AD does not itself set enforcement penalties, the operator’s failure to comply could be recorded as non-conformance with an AD and may be subject to broader regulatory enforcement under CAR 1998 or other applicable aviation safety enforcement provisions beyond this AD text. None of those enforcement mechanisms or penalties are set out in the AD text provided.

• Notification and record implications. The AD’s notification in the Commonwealth Gazette and signature by the CASA delegate are procedural steps that put operators on notice. The AD also specifies methods for accomplishing some documentary requirements (for example, the flight crew briefing and AFM amendment may be accomplished by inserting a copy of the Directive into the respective manuals), which creates a tangible trail maintenance and compliance inspectors can check.

In short, the AD does not itself prescribe specific penalties inside its text. It imposes mandatory duties and a regulatory obligation to comply through the statutory authority cited, and practical enforcement would be via regulatory oversight and compliance verification, none of which are elaborated in the AD document itself.

The AD is issued under a specific regulatory grant and cross-refers to manufacturer service documents and a foreign authority notice. The interactions set out in the AD are limited to the materials it cites.

Statutory basis:

• The AD is issued under subregulation 39.1(1) of CAR 1998. The preamble language states the CASA delegate issues the AD "under subregulation 39.1 (1) of CAR 1998" and that it requires the action set out in the requirement section which the delegate "considers necessary to correct the unsafe condition." The AD thus sits within the regulatory framework of CAR 1998 insofar as the issuing power is concerned.

Manufacturer service documentation:

• The AD explicitly directs operators to perform Requirements 1 and 2 "in accordance with the Accomplishment Instructions of the Bombardier Alert Service Bulletin (ASB) A601R-28-045, Revision A, dated 7 December 2001." Requirement 6 requires determination of fuel vent system modification "in accordance with Bombardier Service Bulletin 601R-28-024, Revision A, dated 11 November 1998." The AD therefore imports the technical instructions and the detail of those manufacturer documents by reference for accomplishment instructions. The AD does not reproduce those instructions in full but makes compliance contingent on following them.

Foreign authority reference:

• The AD notes "Transport Canada CF-2001-47 refers." That indicates the AD is aligned with a Transport Canada action addressing the same unsafe condition. The AD text does not elaborate the content of CF-2001-47 beyond noting it as the referenced authority.

Aircraft documentation and flight operations manuals:

• The AD mandates amendments or insertions into aircraft manuals. Requirement 5 allows the flight crew briefing to be accomplished by inserting a copy of the Directive into the Aircraft Operations Manual. Requirement 6 requires that the AFM limitation section be amended to reflect the centre tank fuel limit where the vent modification has not been incorporated; the AD says this amendment "may be accomplished by inserting a copy of this Directive into the AFM limitation section." This creates a direct interaction between the AD and operators’ flight manuals and operations manuals.

Absence of explicit interaction statements:

• The AD text does not set out how it interacts with other statutory enforcement provisions, penalty regimes, or separate regulatory instruments. It also does not specify whether compliance with the Bombardier service bulletins alone satisfies all regulatory requirements; the AD prescribes following those documents for certain tasks but some duties (for example, AFM amendments and briefings) are specified directly in the AD.

In practice, therefore, the AD binds operators under CAR 1998 authority, references Bombardier ASB and SB for technical accomplishment instructions and notes a Transport Canada reference. The AD creates specific obligations for maintenance and flight manual documentation that interact with operators’ continuing airworthiness and operational procedures. The AD does not on its face modify or repeal other laws or set out how it interacts with criminal or civil liability regimes.

The AD document contains a limited set of dated references and a single AD version identifier; the AD text itself does not record a sequence of amendments to the AD after its issue. The amendment-relevant items present within the AD text are:

• AD identification: The AD is labelled AD/CL-600/47 Center Tank Fuel Transfer Shutoff Valve 2/2002. Despite the "2/2002" label, the signature block shows the delegate signed the AD on 17 December 2001 and the AD became effective on 19 December 2001, and the AD was notified in the Commonwealth Gazette on 19 December 2001.

• Manufacturer service document revisions referenced in the AD: The AD requires actions "in accordance with the Accomplishment Instructions of the Bombardier Alert Service Bulletin (ASB) A601R-28-045, Revision A, dated 7 December 2001" for Requirements 1 and 2. Requirement 6 requires determination of fuel vent system modification "in accordance with Bombardier Service Bulletin 601R-28-024, Revision A, dated 11 November 1998." Those are manufacturer document revision dates incorporated into the AD.

• Transport Canada reference: The AD notes that "Transport Canada CF-2001-47 refers." That indicates the AD is a local regulatory action that references a corresponding foreign authority directive.

• Internal AD text repetition and apparent inconsistency: The AD text contains a repeated paragraph concerning the flight crew briefing and a repetition of the applicability statement that creates an apparent discrepancy: at the head of the AD the Applicability line states "serial numbers 7003 and subsequent," while elsewhere in the AD the text states "Applicable to aircraft with serial numbers 7003 through 7109." The AD text does not provide an explanatory amendment or clarification of this difference within the document.

The AD does not itself include subsequent amendment entries, errata, or superseding ADs in the text provided. It does not indicate any later changes to the requirements or compliance times within the supplied document. Therefore the only amendment-related facts recorded in the document provided are the AD’s own issuance details (signed 17 December 2001, effective 19 December 2001), the manufacturer service bulletin revision dates the AD incorporates by reference, and the Transport Canada reference.

Operators should note the AD’s use of revision identifiers for the ASB and SB (both Revision A) and the AD numbering that includes "2/2002" while bearing a December 2001 effective date; any internal programme that relies on parsing AD identifiers should use the effective date and the AD text for compliance windows rather than relying solely on the AD label.

The AD text contains no litigation history. There are no judicial decisions, administrative appeals, or enforcement actions referenced in the document. The AD provides no record of disputes about its validity, scope or interpretation in judicial or administrative fora.

Implications of the absence of litigation history in the AD text:

• No precedent for interpretation set out in the document. Because the AD contains no litigation references, operators and advisers cannot rely on case law or published determinations within the AD text to resolve ambiguities such as the applicability serial number discrepancy that appears in the AD. The AD itself is the primary source of obligations and procedural instruction in the document provided.

• Enforcement and contested compliance are not illustrated. The AD does not include examples of contested enforcement outcomes or appeals in the text; the document provides only the regulatory requirements and compliance times.

• Practical consequence for operators. Where the AD contains ambiguous wording (for example, the two differing applicability statements), the absence of litigation or appeal history in the AD text means there is no internal precedent within the document to resolve the inconsistency. Operators will need to rely on further CASA guidance, direct enquiries to the issuing authority, or subsequent ADs or notices (none of which appear in the text provided) to clarify interpretive questions.

• Record-keeping and defence. In the event of subsequent enforcement action, operators would likely need to demonstrate compliance with the precise actions and timelines in the AD as written, and that demonstration will depend on maintenance records, AFM/operations manual insertions and briefing records. The AD itself does not provide guidance on the evidence required. The AD’s inclusion in the Commonwealth Gazette evidences formal promulgation on 19 December 2001, and the signature block records the delegate and signing date.

Because the document supplied contains no litigation or administrative appeal narrative, this section records the absence of such history in the AD text and highlights the practical implications for interpretation and compliance verification.

The AD text contains a number of practical pitfalls and drafting quirks that operators and advisers should note because they affect interpretation, scheduling and compliance proof.

1. Applicability wording inconsistency. The AD initially states "Applicability: CL-600-2B19 'Regional Jet' aircraft, serial numbers 7003 and subsequent. Requirement: Applicable to all affected aircraft." Later, the AD repeats an applicability statement that limits applicability to aircraft with serial numbers "7003 through 7109." The text thus contains both "7003 and subsequent" and "7003 through 7109." The AD does not resolve this apparent discrepancy within the text provided. Operators must not assume which statement governs without seeking authoritative clarification from CASA or the AD issuing delegate because the two formulations produce materially different enumerations of affected aircraft.

2. Duplicate/duplicated text lines. The flight crew briefing paragraph appears twice verbatim in the AD text. While this does not change the substance of the obligation, it suggests the document contains editorial duplication and operators should rely on the substantive instruction rather than procedural form. When creating AFM/Operations Manual inserts or briefing checklists, use the substantive content rather than copying duplicated paragraphs verbatim without verification.

3. Conditional reconnection only after verification of parts. Requirement 4 permits reconnection of circuit breaker wires, removal of lock rings and resetting of associated circuit breakers only "If, as a result of Requirement 3, it has been verified that only valves with P/N 601R62256-3 are installed." That means reconnection is not allowed until complete verification that all installed valves are the acceptable P/N. Partial replacement without complete verification would not satisfy Requirement 4. Maintenance planners should treat this as an all-or-nothing condition.

4. Staggered but tight deadlines. The AD sets Requirement 1 to be done "within one day" and Requirement 2 within four days of the effective date, while Requirement 3 (parts identification and replacement) has a 45-day window. Operators must be prepared to perform immediate electrical isolation and wire stowage rapidly, including having maintenance staff and documentation available within a 24-hour window from 19 December 2001. Resource planning, crew scheduling and spare parts sourcing must take account of these timelines.

5. Permitted dispatch with inoperative valves but subject to limits depending on vent modification status. Requirement 5 permits dispatch with inoperative valves provided the breakers are opened per Requirement 1 and subject to Requirement 6. Requirement 6 determines whether the Bombardier vent system modification has been incorporated; if not, aircraft "must operate with less than 200 pounds of fuel in the centre fuel tank" and the AFM must be amended. Practically, this means some aircraft may be permitted to depart with inoperative valves and a full centre tank while others must impose strict fuel limits. Operators must ensure the correct path is chosen based on the fuel vent modification status.

6. Use of manufacturer service documents by reference. The AD requires compliance "in accordance with the Accomplishment Instructions of" Bombardier ASB A601R-28-045 Revision A for the breaker/wire tasks and cross-refers to Bombardier SB 601R-28-024 Revision A for vent system modification determination. Operators must have these specific revision documents on hand and must follow their instructions literally. The AD does not reproduce those instructions.

7. AFM and operations manual amendments permitted by simple insertions. The AD allows that the flight crew briefing and the AFM limitation amendment "may be accomplished by inserting a copy of this Directive into" the Aircraft Operations Manual or AFM limitation section. That is an administratively simple permitted method but operators should ensure that such insertions meet their internal quality assurance and documentation control procedures so that inspectors will accept them as compliant.

8. AD label and effective date mismatch. The AD is labelled "2/2002" but is signed on 17 December 2001 and effective from 19 December 2001. Rely on the effective date and the text for compliance windows rather than the AD label alone.

9. No penalty text in the AD. The AD does not set out enforcement mechanisms or penalties. Operators should be aware that other regulatory provisions not included in the AD text likely govern enforcement and penalties; absence of penalty language in the AD does not mean non-compliance is without consequence.

10. Record-evidence obligations implied but not specified. The AD requires actions and allows certain methods to document them (insert copy of AD into manuals), but does not explicitly prescribe the exact record format or retention period for maintenance actions and briefs. Operators should ensure maintenance entries, parts traceability (P/N verification), and briefing logs are created and retained under their existing continuing airworthiness and operations record-keeping regimes.

Each of these points flows from the AD text. They are practical hazards for implementation and interpretation; operators should seek authoritative clarification from CASA where ambiguity exists, particularly on applicability and any inconsistent statements in the AD.

This section sets out a pragmatic compliance checklist derived directly from the AD’s Requirements and Compliance section, with actions, references and timing as specified in the AD text. Follow the exact Bombardier service documents cited where applicable.

Immediate (within one day of effective date , effective date is 19 December 2001):

1. Identify whether each aircraft in your fleet matches the AD’s applicability. The AD provides two applicability statements: "CL-600-2B19 'Regional Jet' aircraft, serial numbers 7003 and subsequent" and elsewhere "applicable to aircraft with serial numbers 7003 through 7109." Until you obtain formal clarification from CASA, treat aircraft with serial numbers 7003 through 7109 as certainly included. Operators should verify serial numbers and log which aircraft are captured.

2. Requirement 1: Open the applicable circuit breakers and install lock rings in accordance with Bombardier Alert Service Bulletin A601R-28-045 Revision A dated 7 December 2001. Complete this step within one day after the AD’s effective date. Ensure maintenance personnel have the ASB Revision A document and follow its Accomplishment Instructions exactly. Record the maintenance action in the aircraft’s maintenance log, identify the breakers by system/location, and tag as required.

3. Requirement 6 (initial determination): Determine whether the aircraft has incorporated Bombardier Service Bulletin 601R-28-024 Revision A dated 11 November 1998 (the fuel vent system modification). This determination must be done within one day after the effective date and must be documented. If the vent modification has not been carried out, apply the AFM limitation described below.

Short term (within four days after effective date):

4. Requirement 2: Disconnect and stow the electrical wires from the circuit breakers that were opened per Requirement 1, again following the Accomplishment Instructions of Bombardier ASB A601R-28-045 Revision A. Complete within four days. Record the wire disconnection and stowage work, including photos or tag references if your record-keeping procedures permit.

Flight operations and documentation (effective immediately, until Requirement 4 is accomplished):

5. Requirement 5: If operating aircraft with inoperative centre tank fuel transfer shutoff valves (i.e. breakers opened per Requirement 1), ensure the flight crew is briefed that the wing tanks will indicate full until the centre tank is empty and that an EICAS message "LR XFER SOV" will be indicated on the ground and may disappear during climb but will remain on for the remainder of the flight. The AD permits that this briefing "may be accomplished by inserting a copy of this Directive into the Aircraft Operations Manual." Ensure the insertion is controlled and dated, briefings are logged, and operations personnel are instructed to follow the crew briefing requirements.

6. If the vent system modification has not been incorporated (Requirement 6 determination negative), amend the AFM limitation section to reflect operation with less than 200 pounds of fuel in the centre tank. The AD permits the AFM amendment to be accomplished by inserting a copy of this Directive into the AFM limitation section. Ensure the AFM insertion is formalised under your document control and that dispatchers and flight planning staff are notified that affected aircraft must comply with the <200 lb centre tank limit while operating with inoperative valves.

Medium term (within 45 days):

7. Requirement 3: Determine the part number of all fuel transfer shutoff valves installed in the centre fuel tank. Where any valve is P/N 601R62256-5, replace it with P/N 601R62256-3. Complete the parts identification and replacement activity within 45 days after the effective date. Maintenance records should document existing and replaced P/Ns, provide traceability of replaced component serial numbers (where applicable), and reference the AD and Bombardier ASB as the work basis.

8. Requirement 4: If, after the P/N determinations and any necessary replacements, it has been verified that only valves with P/N 601R62256-3 are installed, reconnect the circuit breaker wires that were disconnected and stowed per Requirement 2, remove the lock rings and reset the associated circuit breakers. Requirement 4 is to be accomplished concurrent with Requirement 3, meaning that once the P/N verification confirms only -3 valves are installed, the reconnection and removal of lock rings can be performed. Ensure reconnection is only performed after the verification is complete and recorded.

Records and documentation to maintain:

9. Maintain contemporaneous maintenance entries documenting completion dates for Requirements 1, 2, 3 and 4, referencing Bombardier ASB A601R-28-045 Revision A and SB 601R-28-024 Revision A where applicable. For Requirement 3 replacements, document the outgoing P/Ns and incoming P/Ns, installation dates, technician signatures and relevant task cards.

10. Record flight crew briefings and operations manual/AFM insertions. If you accomplish briefings or AFM amendments by inserting the AD into the relevant manuals as permitted, log the insertion, its date, the aircraft it applies to and the authorising maintenance or operations manager. Keep copies of inserted AD pages with controlled document identifiers if your organisation requires that.

Parts procurement and logistics:

11. If P/N 601R62256-3 valves are not already in stock, place orders promptly to meet the 45-day replacement deadline. Record purchase orders and delivery dates. Keep a spare-plan for aircraft where the vent modification has not been incorporated and the <200 lb centre tank limit applies, as fuel planning for dispatch may be affected.

Clarifications and liaison:

12. Seek CASA clarification regarding the applicability discrepancy between "7003 and subsequent" and "7003 through 7109" as soon as possible and document that request and any response. Because the AD is the definitive obligation, obtain written confirmation on which aircraft serial numbers are captured if there is uncertainty.

13. Retain copies of Bombardier ASB A601R-28-045 Revision A (7 December 2001), Bombardier SB 601R-28-024 Revision A (11 November 1998) and Transport Canada CF-2001-47 if you obtain them, and cross-reference them in your maintenance records. The AD requires the ASB for the breaker/wiring steps and references the SB for vent system modification determination.

Audit readiness:

14. Prepare a compliance package that includes: serial number applicability confirmation, maintenance log entries for Requirements 1 through 4, P/N verification lists and replacement receipts, AFM/Operations Manual insertions and flight crew briefing logs, and correspondence with CASA if any clarifications were sought. This will support any regulatory inspection or audit.

The above steps flow directly from the AD’s requirements and compliance windows. Operators should execute the steps in the stated time frames and maintain documentary evidence of completion. Where the AD text is ambiguous, particularly on applicability, seek formal clarification from CASA and retain that correspondence.