AD/CL-600/78 Amdt 1 - Engine Throttle Control Gearbox

The AD articulates several core concepts that determine its scope, effect and operational mechanics.

Applicability: The AD is narrowly targeted by aircraft model and by installed component part numbers. It applies to "All Bombardier Inc. model CL-600-2B19 aircraft that have engine Throttle Control Gearbox (TCGB) Part Number (P/N): 2100140-003 or 2100140-005 or P/N 2100140-007 installed" (AD/CL-600/78 Amdt 1, Applicability). This is a classic AD approach that limits imposed requirements to aircraft with the specified, potentially defect-prone parts installed.

MRM and CMR transposition: The Requirement block commands updating the CL-600-2B19 Maintenance Requirements Manual (MRM), CSP A-053, to "incorporate the Temporary Revision (TR) 2A-47 for compliance with CMR Task # C76-11-127-01 requirements" (AD/CL-600/78 Amdt 1, Requirement). That transposition moves inspection and corrective action obligations into the MRM as a Certification Maintenance Requirement task. In practical terms, the MRM is the operator’s formalised schedule of recurring maintenance items that an operator must follow to remain airworthy; the CMR designation signals that the task is a certification-linked, mandated requirement for continued airworthiness.

Service Bulletin lineage: The Background shows the AD’s lineage to a manufacturer Service Bulletin, SB 601R-76-019, which "introduced an inspection of, and if required, replacement of the throttle control gearbox with a serviceable unit" (Background). Earlier AD versions mandated SB compliance. Now the inspection requirements are transcribed into a CMR task and incorporated into the MRM through the TR.

Failure mechanism and operational risk: The AD articulates the technical fault and the safety consequence. It records "numerous reported failures" of the TCGB P/Ns listed, and that "some of these failures have resulted in in-flight engine shutdowns" (Background). The causal mechanism is "excessive wear within the engine TCGB" which "could alter the rigging position or cause the throttle to jam," and altered rigging can permit movement towards idle that is "too close to the fuel shut-off position" potentially causing flame out (Background). The AD therefore links a component wear mechanism to an immediate operational safety outcome.

Effective dates and compliance window: The amendment "becomes effective on 15 October 2009" and requires operators to update the MRM "Within 30 days from the effective date of this AD" (AD/CL-600/78 Amdt 1, Compliance). The AD also records the original AD effective date as 30 August 2007, signalling prior regulatory activity on the same issue.

Reference to other authorities: The AD includes a note calling attention to a Transport Canada AD: "Note: Transport Canada AD CF-2004-01R2 dated 29 September 2009 refers." That shows transnational regulatory cross-reference between CASA and Transport Canada documents, reflecting the manufacturer’s and other authorities’ involvement in the safety action.

Delegated signature: The document is signed by "David Villiers, Delegate of the Civil Aviation Safety Authority" and dated 9 October 2009, indicating administrative provenance and the regulatory office issuing the AD.

Together, these concepts define a targeted, process-focused regulatory intervention: identify affected aircraft by part number, mandate incorporation of a specific TR into the MRM to create a CMR task, and require that this be done within 30 days of the AD’s effective date to address a component failure mode that has caused in-flight shutdowns.

The AD identifies a limited set of stakeholders by operation and by installed equipment. Primary affected parties are operators of Bombardier Inc. model CL-600-2B19 aircraft on which an engine Throttle Control Gearbox bearing part number 2100140-003, 2100140-005 or 2100140-007 is installed. The Applicability clause is explicit: "All Bombardier Inc. model CL-600-2B19 aircraft that have engine Throttle Control Gearbox (TCGB) Part Number (P/N): 2100140-003 or 2100140-005 or P/N 2100140-007 installed" (AD/CL-600/78 Amdt 1, Applicability). That means an operator who does not have those TCGB P/Ns installed is outside the AD’s direct scope.

Aircraft owners and operators: The immediate compliance obligation , updating CSP A-053, the Maintenance Requirements Manual (MRM), to include TR 2A-47 , falls on the operator or the organisation responsible for the aircraft’s maintenance control documentation. Operators control the MRM used for continued airworthiness planning and will therefore need to perform the documentary change and ensure maintenance programs follow the incorporated CMR task.

Maintenance organisations and engineers: The maintenance organisations that implement the MRM tasks are indirectly affected. Once the TR is incorporated into the MRM as a CMR task, maintainers must follow the inspection and replacement procedures required by CMR Task # C76-11-127-01 as documented by TR 2A-47 and as derived from SB 601R-76-019 where applicable. The Background states that Bombardier’s SB introduced an inspection and replacement regime, now transcribed into the CMR; maintainers will implement that regime under the MRM.

Regulators: The Civil Aviation Safety Authority, represented by the AD and its delegate signature, is the issuing regulator. The AD also references a Transport Canada AD, which indicates related activity by another regulatory jurisdiction. Internationally, the manufacturer and foreign civil aviation authorities are relevant stakeholders given the Service Bulletin and cross-references.

Parts suppliers and OEM support: Entities supplying replacement TCGB units, or providing overhaul and repair services for the listed TCGB part numbers, will experience demand from operators who need serviceable units as contemplated in SB 601R-76-019 and the CMR task. The Background explicitly notes replacement with a "serviceable unit" as an element of the SB and earlier mandated inspection regimes.

Ancillary stakeholders: Flight operations and scheduling teams will be affected indirectly through potential maintenance downtime if inspections or replacements require out-of-service time. Insurers may be attentive to compliance history where in-flight shutdowns are involved, though the AD text contains no provisions addressing insurance or claims.

Excluded parties: Owners or operators of CL-600-2B19 aircraft that do not have the listed TCGB part numbers installed are not covered by the AD. The text does not indicate any retrofitting or universal requirement across all CL-600 series; applicability is explicitly limited by P/N.

In summary, the AD imposes a near-term documentation and maintenance-process obligation on operators with affected TCGB P/Ns installed, cascades operational tasks to maintenance organisations, and creates demand for serviceable TCGB units where replacements are required. The AD’s delineation by P/N and model makes the set of affected entities definable by technical configuration rather than by operator size or ownership.

The AD sets a single, specific duty and leaves few express rights or discretionary provisions in the text. The controlling duty is to update the operator’s Maintenance Requirements Manual (MRM) to incorporate Temporary Revision (TR) 2A-47 so that the operator is in compliance with CMR Task # C76-11-127-01.

Duty to update MRM: The Requirement clause mandates the MRM update: "Update the CL-600-2B19 Maintenance Requirements Manual (MRM) document (CSP A-053) to incorporate the Temporary Revision (TR) 2A-47 for compliance with CMR Task # C76-11-127-01 requirements." The Compliance clause sets the timeline: the update must be completed "Within 30 days from the effective date of this AD." The amendment "becomes effective on 15 October 2009." Therefore the obligation is a documented change to the operator’s maintenance programme within a short, fixed period.

Duty to perform inspections/replacements as per CMR: While not spelled out line-by-line in the AD text itself, the AD transposes existing inspection/replacement requirements into a CMR task. The Background explains that Bombardier’s SB 601R-76-019 "introduced an inspection of, and if required, replacement of the throttle control gearbox with a serviceable unit" and that "The subject TCGB inspection requirements mandated as per the earlier versions of this AD are now transcribed in a new Certification Maintenance Requirement (CMR) task." By instructing incorporation of TR 2A-47 to satisfy CMR Task # C76-11-127-01, the AD establishes an enforceable maintenance duty tied to that CMR.

Documentation duty: Operators must ensure that CSP A-053 is updated. The MRM is the formalised record that inspectors, maintenance organisations and regulators will rely on to judge compliance with maintenance obligations. The AD therefore imposes a duty of documentary fidelity as well as an operational maintenance duty.

Rights, discretion and exemptions: The AD text does not provide express rights of exemption, alternative methods of compliance, or appeal routes within the body of the printed AD. It does reference Transport Canada AD CF-2004-01R2, but that is a cross-reference rather than a procedural right. As issued material, the AD binds the operator to the stated compliance action; any rights to seek alternate compliance or extensions are not described in the text provided. The AD does not specify a process for requesting relief or alternative compliance; those procedures, if available, are ordinarily set out in the regulator’s administrative rules rather than in the AD text itself. The AD contains no waiver clause.

Burden allocation: The duty rests on the operator to perform the MRM update "Within 30 days" and to follow the incorporated CMR task thereafter. Implicitly, the operator bears the costs of any inspections, replacements, parts procurement and downtime incurred as a result of the CMR. The AD expressly acknowledges previous requirements that mandated inspection and replacement, and now codifies them in the MRM; it does not mitigate or limit the operator’s maintenance obligations.

Temporal effect: The AD notes that the original issue "became effective on 30 August 2007" and that this amendment "becomes effective on 15 October 2009." The duty to update the MRM applies from the effective date of the amendment and must be completed within 30 days thereafter.

Allocation of decision-making: The AD delegates the implementation details to the operator and its maintenance organisation, insofar as the operator must adopt TR 2A-47 into CSP A-053 and then follow the maintenance tasks it prescribes. The AD does not specify how an operator must document completion beyond updating the MRM itself; standard practice would be record-keeping within the operator’s maintenance records.

In sum, the AD creates a mandatory, time‑bounded administrative and maintenance duty on operators with specified TCGB part numbers, transposes inspection/replacement mandates into the operator’s MRM via a CMR task, and leaves no express alternative compliance or waiver provisions within the AD text itself.

The AD text does not specify monetary penalties, criminal sanctions, or explicit enforcement procedures within its printed content. It is an administrative instrument issued by the Civil Aviation Safety Authority, signed by "David Villiers, Delegate of the Civil Aviation Safety Authority" and dated 9 October 2009, with an effective date of 15 October 2009. The document requires that the MRM be updated "Within 30 days from the effective date of this AD" but does not in the text set out the enforcement mechanisms or penalties for non-compliance.

Regulatory provenance and implied enforcement: An AD is an enforceable regulatory instrument in aviation safety practice. The AD is issued under the authority of the Civil Aviation Safety Authority as indicated by the signature block. Non-compliance with an AD would typically expose an operator to regulatory enforcement actions under the enabling aviation safety legislation and regulations, though those specific statutory mechanisms are not reproduced in this AD text. The AD’s own language does not spell out those enforcement avenues, nor does it quantify penalties or administrative sanctions.

Evidence-centric enforcement: The Compliance requirement is documentary and time-limited. Enforcement, in practice, will depend on evidence that the operator has updated CSP A-053 to incorporate TR 2A-47 and is following the CMR Task # C76-11-127-01. Since the AD directs a change to the MRM, inspectors and auditors would verify compliance through maintenance programme documentation and maintenance records. The AD places the burden on the operator to effect and record the update within the stated timeframe.

Cross‑reference to other authorities: The AD notes a reference to "Transport Canada AD CF-2004-01R2 dated 29 September 2009." That cross-reference indicates that other national authorities have pursued related enforcement or safety action; it also signals potential mutual awareness or reciprocal enforcement activity between CASA and Transport Canada concerning the safety issue. The AD itself does not describe the enforcement regime applied by Transport Canada.

Absence of alternative compliance text: The AD does not include an "Alternative Methods of Compliance" clause or a procedural route for operators to request relief, extensions, or equivalent measures. The absence of such a clause in this printed AD text means that any relief or discretionary enforcement decision would be handled under CASA’s broader administrative procedures rather than by reference to the AD’s text.

Operational consequences of non-compliance: The Background records that TCGB failures have resulted in in‑flight engine shutdowns, identifying a clear operational safety risk. Regulators would likely treat non-compliance with an AD addressing an in-flight shut-down risk seriously. That said, the AD text does not itself list specific consequences, fines or administrative sanctions. Those consequences would flow from the broader aviation regulatory framework and enforcement policies outside the printed AD.

In short, the AD mandates compliance within a short timeframe but does not itself specify the enforcement instruments or penalties. Enforcement will depend on CASA’s statutory powers and regulatory enforcement processes, and compliance will be verifiable by documentary evidence that CSP A-053 was updated to include TR 2A-47 and that the operator is carrying out the CMR task.

The AD interacts primarily with the operator’s internal maintenance system and with external regulatory and manufacturer materials. The text explicitly references both a manufacturer Service Bulletin and a corresponding Transport Canada AD, which situates the instrument within a web of overlapping safety directives and documents.

Relationship with Maintenance Requirements Manual and Certification Maintenance Requirements: The AD requires incorporation of Temporary Revision 2A-47 into CSP A-053, the CL-600-2B19 Maintenance Requirements Manual. The MRM is the operator’s formal vehicle for scheduling mandated maintenance tasks. By transcribing inspection requirements into a CMR task, the AD aligns the maintenance obligations with certification-linked requirements. The AD therefore changes the content of the operator’s maintenance regime from ad hoc or stand-alone compliance with a Service Bulletin to a recurring, documented CMR task reflected in the MRM.

Manufacturer documentation and Service Bulletin: The Background identifies Bombardier Service Bulletin 601R-76-019, dated 21 August 2003, as the origin of inspection and replacement actions: "Bombardier issued Service Bulletin (SB) 601R-76-019 dated 21 August 2003, to introduce an inspection of, and if required, replacement of the throttle control gearbox with a serviceable unit." Earlier AD versions mandated compliance with SB 601R-76-019. The current AD transposes those SB-based inspection requirements into a CMR, creating a formal link between manufacturer recommendations and the certified maintenance programme.

Cross-jurisdictional references: The AD contains a note that "Transport Canada AD CF-2004-01R2 dated 29 September 2009 refers." That indicates that the same safety matter has been addressed in a Transport Canada AD and that CASA is aligning its regulatory action with international counterparts. The AD text does not articulate the legal effect of the Transport Canada AD within Australia, but the cross-reference records parallel actions and provides a traceable regulatory lineage to foreign authority measures.

Hierarchy of requirements: The AD sits above the operator’s MRM in the sense that the operator must update its MRM to reflect the CMR task mandated by the AD. The AD references manufacturer SBs and a Transport Canada AD as sources of technical content. In practice, if there is any inconsistency between the AD’s mandated requirement to incorporate a specific TR and prior MRM entries, the AD command will prevail for compliance with CASA’s directive. The AD’s purpose is to harmonise and elevate the inspection obligations into the formal maintenance framework used for certification oversight.

Absence of statutory text in AD: The AD itself does not quote the statutory enabling provision or the penalty provisions of the Civil Aviation Act or associated regulations. Therefore, while the AD is a regulatory instrument under CASA, the precise statutory mechanisms that give the AD legal force, and the enforcement tools available for breaches, are not set out in the AD text. Any interaction with administrative law remedies, judicial review, or enforcement procedures will rely on the broader legislative framework rather than the content of the AD.

Operational interface with maintenance records and compliance audit processes: By requiring a TR in the MRM and a CMR task, the AD prescribes a documentary change that will be reviewed during audits. The MRM’s updated content will be the basis on which CASA or its delegates judge continued airworthiness compliance. Therefore, the AD interacts with regulatory audit regimes, record-keeping obligations and the certification regime for maintenance personnel and organisations, though the AD does not describe those regimes in its text.

In summary, the AD interacts with manufacturer Service Bulletins, international counterpart ADs, the operator’s MRM and certification-linked maintenance tasks, and with the broader regulatory oversight and audit mechanisms. It modifies the operator’s documented maintenance obligations and thereby intersects with record-keeping, audit and certification processes under the aviation regulatory framework.

The AD text documents a short, discrete amendment history within the document itself. The amendment is labelled "AD/CL-600/78 Amdt 1" and is dated 21/2009 with an effective date for this amendment of 15 October 2009. The AD records that the "original issue of this AD became effective on 30 August 2007." The Background explains the trajectory from manufacturer Service Bulletin to earlier ADs to the present amendment.

Key events recorded in the AD text:

• Manufacturer action: Bombardier issued Service Bulletin (SB) 601R-76-019 on 21 August 2003, which introduced an inspection and replacement regime for the throttle control gearbox. The Background states: "Bombardier issued Service Bulletin (SB) 601R-76-019 dated 21 August 2003, to introduce an inspection of, and if required, replacement of the throttle control gearbox with a serviceable unit."
• Original AD issuance: The AD records that its "original issue ... became effective on 30 August 2007." The AD does not reproduce the text of the 2007 version in full, but it identifies that earlier AD versions mandated the inspection introduced by the SB and subsequent revisions.
• Amendment issuance: This amendment, AD/CL-600/78 Amdt 1, was prepared and signed on 9 October 2009 by a CASA delegate and "becomes effective on 15 October 2009." The Compliance clause requires action "Within 30 days from the effective date of this AD."

Reason for amendment: The Background explains why the amendment was issued: to "mandate the incorporation of the new CMR task into the CL-600-2B19 MRM, as introduced by the MRM TR 2A-47." It further explains that "The subject TCGB inspection requirements mandated as per the earlier versions of this AD are now transcribed in a new Certification Maintenance Requirement (CMR) task." Thus the amendment’s functional purpose is codifying inspection/replacement requirements into the MRM via a CMR rather than continuing to rely solely on prior AD or SB references.

Reference to other regulatory amendments: The AD contains a note referencing "Transport Canada AD CF-2004-01R2 dated 29 September 2009." That foreign AD appears to be contemporaneous and relevant to the subject matter, suggesting coordinated international action. The AD does not provide the text of the Transport Canada AD but records its existence for cross-reference.

Administrative authorship and date: The AD is signed "9 October 2009" by a CASA delegate, David Villiers. The amendment header contains the label "21/2009" which appears to be a catalogue or sequence identifier; the AD is titled in the header as "AD/CL-600/78 Amdt 1 | Engine Throttle Control Gearbox | 21/2009."

No other amendments recorded in text: The AD does not list subsequent amendments or prior amendment numbers apart from the original 2007 effective date and this current amendment. The reader therefore can see a clear sequence: SB in 2003, original AD effective 2007, and amendment effective 15 October 2009 to bring the content into the MRM as a CMR task.

In short, the amendment history within this document traces a progression from manufacturer SB action through an initial AD to this amendment which transposes inspection requirements into the operator’s MRM via a CMR task, with effective dates and administrative signing recorded.

The AD text does not identify any litigation, judicial review, appeals, or court decisions relating to this AD or to the subject matter. No cases, legal proceedings, or dispute resolutions are mentioned in the document. The Background and body of the AD focus exclusively on the technical failure mode, the manufacturer's service bulletins, prior ADs and the administrative amendment to require the MRM update.

Consequences of absence of litigation record in the AD: Because the AD does not reference any litigation or court decisions, the document itself provides no judicial interpretations or precedent concerning the AD’s legal enforceability, permissible scopes of compliance, or challenges to its validity. Where operators or other parties sought legal relief, such actions would ordinarily be documented in public records or separate administrative files; the absence of such references in the AD does not necessarily mean litigation did not occur, but it means that no litigation is recorded within the AD itself.

Practical implications for practitioners: For lawyers, compliance professionals or other readers seeking case law or judicial guidance on the specific obligations created by this AD, the AD provides no decisions to cite. Any legal questions about the AD’s interpretation, the process by which CASA issued it, or the enforcement actions arising from its non-compliance will need to be investigated in court records or administrative tribunal decisions outside the AD text. The AD does include a cross-reference to Transport Canada AD CF-2004-01R2, but that is a regulatory document and is not a judgment.

How to use this absence in legal work: When preparing compliance advice, legal pleadings or audit positions, practitioners must rely on the AD’s plain text and the broader statutory and regulatory framework governing CASA’s powers rather than on litigated interpretations within the AD document. If contested points arise,such as scope of applicability by serial number, acceptable alternative methods of compliance, or the sufficiency of documentary updates,operators or counsel would need to look for case law external to the AD or to seek clarifying administrative guidance from CASA.

In summary, the AD contains no litigation history. The document is a technical and administrative directive that records the rationale and the mandated action, but it does not document any judicial engagement, challenges, or adjudications concerning the AD’s content or administration.

The AD’s narrow language and its placement of obligations into the Maintenance Requirements Manual create several practical traps and compliance risks that operators and maintenance organisations should note. These are derived directly from the AD text and its procedural effects.

Applicability tied to specific P/Ns: The AD applies solely to CL-600-2B19 aircraft with TCGB P/N 2100140-003, 2100140-005, or 2100140-007 installed. A primary compliance risk is misidentifying whether a TCGB carries one of these P/Ns. Operators must verify the part numbers installed on each airframe. The AD’s Applicability clause is explicit: if the listed P/Ns are present, the AD applies. Failure to verify or misreading part numbering could lead to non-compliance or unnecessary action.

Short compliance window: The AD requires the MRM update "Within 30 days from the effective date of this AD" and becomes effective on 15 October 2009. Practically, this is a tight timeframe for organisations that must coordinate document control, training, and maintenance planning. If an operator’s document control procedures are not configured to process and publish an MRM TR within 30 days, the operator may technically be out of compliance. The AD does not provide a grace period.

Documentary obligation as enforcement vector: The AD requires updating CSP A-053 to incorporate TR 2A-47. That creates a documentary compliance obligation which is amenable to inspection and audit. If the MRM is not updated correctly or the TR is not incorporated in the manner expected by CASA, an operator may be cited for non-compliance even if the physical inspections have been performed. The AD therefore requires attention to both the content and the record-keeping process.

Transposition of SB into CMR: The Background explains that prior SB-based inspection requirements have been transcribed into a CMR task. Operators that previously complied with the Service Bulletin on an ad hoc basis should ensure the inspection frequency, methods and corrective actions in their ongoing maintenance programme match the CMR task as incorporated into the MRM. Differences between historical practice and the CMR’s wording might create a compliance gap.

No stated alternative compliance procedure in the AD text: The printed AD does not include an "alternative methods of compliance" provision or an explicit amendment clause for operators that believe they have an equivalent means of mitigating the risk. That leaves little room within the AD itself to document equivalence. Operators seeking an alternative approach would need to rely on CASA’s general administrative channels rather than on the AD text.

Potential operational impact of replacements: The Service Bulletin and Background contemplate "if required, replacement of the throttle control gearbox with a serviceable unit." Operators who discover TCGBs needing replacement will need to source serviceable units, which may involve lead time, costs and potential aircraft downtime. The AD does not provide mitigation measures for parts shortages.

Cross-jurisdictional documentation: The AD cites Transport Canada AD CF-2004-01R2. Operators that operate internationally should check whether their maintenance records and MRM updates satisfy other jurisdictions’ requirements. However, the AD does not spell out harmonisation requirements; operators must manage any differences.

Record dates and version control: The AD notes an original effective date in 2007 and this amendment’s effective date and signature in October 2009. Operators must ensure that they have the correct, current TR (TR 2A-47) and do not mistakenly re-apply or rely on superseded revisions. Misapplying an older TR or failing to incorporate the correct TR number will create an auditable defect.

Responsibility allocation within organisations: The AD places the duty on operators to update the MRM. Organisations where responsibilities are distributed between airworthiness managers, maintenance control and document control must ensure the task is coordinated promptly. Failure to assign responsibility is a common compliance hazard.

Implicit reliance on SB inspection wording: The Background references SB 601R-76-019 and earlier ADs. If an operator’s historic work was done to a revision of the SB different from the TR or CMR wording, the operator must reconcile any differences. That reconciliation is an operational risk area.

In short, the AD’s narrow P/N applicability, short compliance timeframe, documentary focus, lack of alternative compliance language and the potential for parts replacement create concrete compliance pitfalls. Operators should verify part numbers, implement prompt MRM updates, ensure the incorporated CMR task is followed in maintenance practice and maintain traceable records demonstrating the MRM change and the execution of any required inspections and replacements.

The AD sets a clear, single compliance action and a short timeframe. Below are actionable steps, strictly grounded in the AD text, to effect compliance and create an audit trail for CASA or other regulators.

1. Identify affected aircraft by part number

   • Review each Bombardier CL-600-2B19 in the fleet to determine whether an engine Throttle Control Gearbox with part number 2100140-003, 2100140-005 or 2100140-007 is installed. The AD’s Applicability clause makes the obligation conditional on the presence of those P/Ns. Record the P/N and serial number for each installed TCGB in the aircraft’s maintenance records.

2. Obtain the Temporary Revision and CMR task text

   • Acquire Temporary Revision TR 2A-47 for CSP A-053 (the CL-600-2B19 MRM) and the text of Certification Maintenance Requirement Task # C76-11-127-01. The Requirement clause explicitly directs incorporation of TR 2A-47 "for compliance with CMR Task # C76-11-127-01 requirements." Ensure the TR and the CMR task text are the versions specified by Bombardier and as referenced by CASA.

3. Update CSP A-053 within 30 days

   • Incorporate TR 2A-47 into CSP A-053, the Maintenance Requirements Manual for the CL-600-2B19, within 30 days from the AD’s effective date (the AD notes the amendment becomes effective on 15 October 2009). The Compliance clause sets this definitive timeline: "Within 30 days from the effective date of this AD." Follow the organisation’s document control procedures to publish and distribute the revised MRM content to maintenance staff and relevant operational personnel.

4. Implement the CMR task in maintenance planning

   • Once TR 2A-47 is incorporated into CSP A-053, ensure the CMR Task # C76-11-127-01 is scheduled and performed according to the frequencies, inspection methods and corrective actions prescribed. The Background indicates that the inspection procedures are derived from Bombardier SB 601R-76-019 which "introduced an inspection of, and if required, replacement of the throttle control gearbox with a serviceable unit." Maintain completed task records in the aircraft’s maintenance log.

5. Perform inspections and replacements as required

   • Where inspections reveal excessive wear or other defects that meet the replacement criteria, replace the throttle control gearbox with a serviceable unit, consistent with the SB and the CMR task incorporated via the TR. Keep detailed records of parts replaced including P/N and serial numbers, source of the serviceable unit and associated certification paperwork for the replacement parts.

6. Retain documentary proof for audit

   • Maintain records evidencing: the identification of affected P/Ns on specific aircraft, the incorporation of TR 2A-47 into CSP A-053 (including the date of incorporation and document control entries), completed CMR task records for each aircraft (inspection reports, findings, corrective actions), and parts replacement records. Since the AD’s requirement is documentary as well as practical, these records demonstrate compliance.

7. Cross-check international requirements where applicable

   • The AD includes a note referencing "Transport Canada AD CF-2004-01R2 dated 29 September 2009." Operators conducting international operations should confirm that the MRM update and CMR task performance meet any related foreign AD requirements. Document any additional actions taken to satisfy other authorities.

8. Assign internal responsibility and training

   • Designate a responsible person or team to oversee the MRM revision and the ensuing maintenance execution. Inform and, if necessary, train maintenance control and line maintenance personnel on new inspection criteria or replacement thresholds introduced by TR 2A-47 and the CMR task.

9. Monitor parts availability

   • Anticipate potential need for serviceable TCGB units if inspections necessitate replacement. Establish procurement channels and validate the serviceability documentation of replacement units to avoid grounding or schedule disruption.

10. Seek administrative guidance where uncertainty exists

    • The AD text does not contain explicit alternative compliance routes. If an operator believes it has an equivalent maintenance procedure or cannot meet the 30 day deadline because of genuine operational constraints, the operator should engage with CASA through the regulator’s established administrative channels to seek clarification, extension or authorised alternative methods of compliance. Any such engagement should be documented.

Adhering to these steps will align an operator’s practice with the AD’s explicit textual requirements: identify affected aircraft by P/N, obtain and incorporate TR 2A-47 into CSP A-053 to satisfy CMR Task # C76-11-127-01, perform inspections and replacements as required, and retain documentary evidence of the MRM update and maintenance actions. The AD’s Compliance clause and the Background’s linkage to SB 601R-76-019 provide the technical and temporal anchors for these steps.