AD/CL-600/105 - Engine Throttle Control Gearbox

This AD deploys a small set of interlocking maintenance-regulatory concepts. These concepts are stated in the AD text; the list below explains them and indicates where they appear.

• Airworthiness Directive (AD): a mandatory safety directive issued by the regulator. The AD is identified as AD/CL-600/105 1/2009 and is issued by the Civil Aviation Safety Authority (signature and date at the end of the document). The AD is the instrument that imposes the maintenance schedule change (entire document).

• Applicability: the AD applies to Bombardier CL-600-2A12 (CL601) and CL-600-2B16 (601-3A, 601-3R and CL604) aircraft. Applicability is stated at the start of the AD (Applicability).

• Time Limits Maintenance Checks (TLMCs): TLMCs are the named sections of the aircraft maintenance programme into which the new inspection tasks must be inserted. The AD specifies the exact TLMC documents and sections for each variant: PSP 601-5 TLMC Section 5-10-30 for CL601, PSP 601A-5 TLMC Section 5-10-30 for CL601-3A/3R, and CL604 TLMC Section 5-10-40 for CL604 (Requirement).

• Temporary Revisions (TRs): TRs are the mechanism used to introduce the new TLMC tasks. The AD identifies TR 5-236 for CL601 variants and TR 5-2-40 for CL604 as the TRs that introduce Tasks 76-10-00-101 and 76-11-00-101 respectively. The AD also references previous TRs that are superseded (TR 5-224 and TR 5-2-31) but whose earlier compliance satisfies the AD’s intention (Requirement; Background).

• Maintenance tasks and task numbers: the AD prescribes incorporation of Task 76-10-00-101 (CL601/601-3A/3R) and Task 76-11-00-101 (CL604) into the referenced TLMC sections (Requirement).

• Engine Throttle Control Gearbox (ETCG) and part numbers: the safety issue arises from premature wear of the ETCG rack and pinion mechanism. The AD identifies the affected ETCG part numbers as P/N 2100140-005 and P/N 2100140-007 (Background).

• Service Bulletins (SBs): Bombardier published SB 601-0583 (for CL601 variants) and SB 604-76-004 (for CL604) introducing the periodic inspection requirements that the AD now integrates into TLMCs (Background).

• Compliance window and phase-in schedule: the AD requires schedule revision within 30 days of the effective date but permits initial compliance with the new TLMC tasks to follow the phase-in schedules detailed in the TRs. The AD therefore distinguishes between the administrative act of revising an approved maintenance programme and the operational act of performing inspections according to a phase-in schedule (Compliance; Requirement).

• Cross-reference to foreign AD: the AD notes Transport Canada AD CF-2008-32R2 dated 17 November 2008 (Requirement/Note), demonstrating coordination with the state of design or other authority’s AD.

These concepts show the AD’s regulatory architecture: it uses TLMC document changes effected by Temporary Revisions to modify an operator’s approved maintenance schedule, and it links those changes to specific Bombardier service information intended to detect wear in a component identified by part numbers.

The AD’s named affected parties are aircraft of the CL-600 series and, by extension, their operators and maintenance organisations. The Applicability section states the specific aircraft models covered: Bombardier CL-600-2A12 (CL601) and CL-600-2B16 (601-3A, 601-3R and CL604) aircraft. The Requirement section makes clear that the immediate legal duty is to "revise the Transport Canada approved Maintenance Schedule" to incorporate the named TLMC tasks, therefore the primary compliance obligation falls on the holder of that approved maintenance schedule (Applicability; Requirement).

Affected actors include the following, as implicated by the AD’s language:

• Registered owners/operators of the listed CL-600 models who are the holders of a Transport Canada approved Maintenance Schedule. The AD requires that the approved schedule be revised to include the specified TLMC tasks (Requirement).

• Maintenance organisations, maintenance planners and engineers responsible for maintaining TLMC documents and implementing TLMC tasks. They must incorporate Task 76-10-00-101 or Task 76-11-00-101 into the stated TLMC sections and perform, or programme, the inspections in line with the phase-in schedule in the TRs (Requirement; Compliance).

• Certifying staff and mechanics who will carry out the inspections introduced by the Bombardier service bulletins and the TLMC tasks. While the AD does not specify the inspection content in its text, it refers to Bombardier SBs that introduce periodic inspection of the affected rack and pinion mechanism (Background).

• Regulatory authorities and their delegates. The AD itself is issued by the Civil Aviation Safety Authority (signed by the Delegate), and it cross-references a Transport Canada AD; this implicates inter-authority coordination for operators whose maintenance approvals are governed by multiple authorities (signature; Requirement/Note).

• Aircraft operators or maintenance organisations that had already complied with earlier TLMC temporary revisions. The AD explicitly states that previous compliance with superseded TR 5-224 (for CL601) and TR 5-2-31 (for CL604) "satisfies the intention of this AD", so such parties are treated as compliant under the AD’s intent (Requirement).

The AD does not list other parties such as parts suppliers, insurers or third-party lessors, nor does it set out administrative processes for showing compliance, so affected parties must infer the steps: revise the approved maintenance schedule, document the revision, and implement inspections as per the TRs and Bombardier SBs. The immediate cost and operational impact fall primarily on operators and their maintenance supply chain, because they must integrate the new TLMC tasks into their approved programmes and schedule the related inspections under the phase-in arrangements.

The AD imposes a narrow set of duties and records a limited concession; it does not assert a broad set of procedural rights or administrative protections within the text.

Primary duties imposed by the AD (as stated):

• Revise the Transport Canada approved Maintenance Schedule to incorporate the specified tasks. For CL601 this is Task 76-10-00-101 into Section 5-10-30 of PSP 601-5 TLMC and into Section 5-10-30 of PSP 601A-5 TLMC for the CL601-3A and CL601-3R variants; for CL604 this is Task 76-11-00-101 into Section 5-10-40 of the CL604 TLMC (Requirement).

• Ensure the revision is completed within 30 days after the effective date of the AD (Compliance).

• Carry out initial compliance with the new TLMC tasks in accordance with the phase-in schedules contained in the Temporary Revisions TR 5-236 (for CL601 variants) and TR 5-2-40 (for CL604) (Requirement; Compliance).

These duties separate the administrative act of revising an approved maintenance schedule from the operational execution of inspections, the latter subject to a phase-in schedule.

Concessions, clarifications and implied rights noted in the AD:

• Previous compliance with superseded TLMC TRs satisfies the AD’s intention. The AD expressly states that prior compliance with TR 5-224 (CL601) and TR 5-2-31 (CL604) satisfies its intention (Requirement). This is an operational concession that recognises legacy compliance under earlier TRs as effectively meeting the AD’s object.

• Reference to Bombardier service bulletins as the source of the inspection content. The AD records that Bombardier issued SB 601-0583 and SB 604-76-004 introducing periodic inspection of the affected ETCG mechanisms (Background). While the AD does not state that compliance must be exactly to the SBs, the implication is that the TLMC tasks inserted via the TRs embody the SB inspection requirements.

What the AD does not state (absence of explicit rights or processes):

• The AD does not set out an appeal mechanism, an exemption process, documentation submission requirements to CASA, nor does it specify acceptable evidence of compliance. It also does not specify remedial actions in the event wear is detected, nor does it describe testing, removal, overhaul or replacement procedures; those operational details are referenced via Bombardier SBs and the TRs, but they are not repeated in the AD text (Background; Requirement).

• The AD does not set out civil or criminal penalties for non-compliance, nor the enforcement processes. It records the effective date and compliance timeframe but leaves enforcement detail implicit (Compliance).

Practical implications for duties and rights:

• Operators must effect an administrative amendment to the approved maintenance schedule within the 30-day window and then follow the phase-in timetable for carrying out initial inspections as directed by the TRs. Operators who previously complied with the named superseded TRs may rely on that fact as satisfying the AD’s intention. The AD’s text leaves the operational specifics (inspection criteria, thresholds, corrective actions) to the Bombardier SBs and the TR documents referenced.

The AD text does not state specific penalties or describe enforcement procedures. The document sets the obligation to revise the Transport Canada approved Maintenance Schedule and requires compliance within a 30-day window measured from the effective date of the AD (Compliance; Requirement), and it records that the AD becomes effective on 15 January 2009. Beyond those temporal and substantive requirements, the AD itself contains no express penalty clauses, sanction language, or enforcement process in its text.

What the AD does provide that is relevant to enforcement in practice is its formal character and provenance:

• The AD is issued by the Civil Aviation Safety Authority, signed by James Coyne, Delegate of CASA, dated 27 November 2008. That signature identifies the issuing authority (signature block).

• The AD cross-references Transport Canada AD CF-2008-32R2 (Requirement/Note), indicating coordination with the state-of-design authority’s directive. That cross-reference may bear on bilateral acceptance or enforcement where operators hold maintenance approvals under more than one regulator, but the AD text does not elaborate that point.

Because the AD itself does not set out penalties, readers must treat its absence as a textual fact: the instrument prescribes mandatory action but does not specify what penalties will follow from non-compliance. Enforcement mechanisms and sanctions, if any, are outside the text and would exist in the general regulatory framework under CASA and any applicable aviation safety legislation or regulation, which the AD does not recite. The AD therefore communicates duties and a compliance timeframe but leaves the enforcement consequence and procedure to the broader regulatory system rather than within the AD document.

If a reader requires the specific enforcement remedies, administrative processes for notices of non-compliance, or the pathway to obtain relief or an alternative method of compliance, those details must be sought in CASA’s wider regulatory materials and procedures; they are not contained in this AD.

The AD explicitly interacts with a small set of other regulatory and technical instruments; these interactions are stated within the AD.

• Transport Canada AD CF-2008-32R2: The AD includes a note referring to Transport Canada AD CF-2008-32R2 dated 17 November 2008 (Requirement/Note). That reference signals a direct coordination or cross-recognition with the state-of-design or other authority’s AD. The AD’s Requirement to revise a Transport Canada approved Maintenance Schedule and its reference to the Transport Canada AD indicate an interaction with foreign regulatory action, at least as a factual cross-reference.

• Transport Canada approved Maintenance Schedule: The AD requires revision of the “Transport Canada approved Maintenance Schedule” to incorporate TLMC tasks (Requirement). This establishes an operational link: the AD’s change must be reflected in the operator’s maintenance schedule that has been approved by Transport Canada. The AD thereby affects an operator’s obligations under that approved maintenance programme, and any bilateral or regulatory arrangements that govern the acceptance of a Transport Canada approved schedule by CASA-regulated operations will be implicated. The AD does not articulate how CASA and Transport Canada approvals are reconciled, it only requires the revision of the Transport Canada approved schedule.

• Time Limits Maintenance Checks (TLMCs) and Temporary Revisions (TRs): The AD requires insertion of specific TLMC tasks into named TLMCs via Temporary Revisions TR 5-236 (CL601 variants) and TR 5-2-40 (CL604). It also recognises earlier TRs (TR 5-224 and TR 5-2-31) as superseded but sufficient for satisfying the AD’s intention if already complied with (Requirement; Background). This cross-links the AD to the TLMC administrative regime and to the TR process as the vehicle for updating maintenance programmes.

• Bombardier Service Bulletins: The AD records that Bombardier issued SB 601-0583 and SB 604-76-004 introducing the periodic inspections for the affected ETCG rack and pinion mechanisms (Background). While the AD does not verbatim adopt the SB text, it effectively folds the SB inspection requirement into an operator’s TLMC through the TRs. That creates an interaction between manufacturer technical guidance and regulatory maintenance obligations.

Absent from the AD text are any cross-references to criminal statutes, civil liability regimes, insurance requirements, or other aviation regulations. The AD itself constrains its interactions to maintenance programmes, manufacturer SBs, TR documents, and a referenced Transport Canada AD. It does not, for example, purport to amend or override other legislation; it operates by imposing a change to an approved maintenance schedule and by requiring compliance with specified TLMC tasks according to TR phase-in schedules.

Operators whose regulatory or contractual arrangements depend on maintenance schedules approved by authorities other than Transport Canada should take note that this AD is framed around the Transport Canada approved Maintenance Schedule. The AD does not resolve administrative questions about how the required amendment should be recorded for operators holding approvals under other states or under CASA; those questions sit in the broader regulatory and bilateral-acceptance framework, which the AD does not itself articulate.

The AD text itself contains a concise amendment and temporary-revision history relevant to the TLMC tasks it requires. The key points recorded in the document are the following.

• Temporary Revisions introducing the tasks: The AD instructs the incorporation of Task 76-10-00-101 into Section 5-10-30 of PSP 601-5 TLMC for the CL601 variant and into Section 5-10-30 of PSP 601A-5 TLMC for CL601-3A & 3R variants, and the incorporation of Task 76-11-00-101 into Section 5-10-40 of the CL604 TLMC. These insertions are introduced via Temporary Revision TR 5-236 for CL601 variants and TR 5-2-40 for CL604 (Requirement).

• Superseded TRs and acceptance: The AD explicitly notes that "Previous compliance with superseded TLMC TR 5-224 for variant CL 601, and TR 5-2-31 for variant CL604, satisfies the intention of this AD." That language documents the amendment lineage and clarifies that operators who already adopted the earlier TRs are treated as meeting the AD’s intention (Requirement).

• Bombardier Service Bulletins: The AD records that Bombardier issued Service Bulletins SB 601-0583 (CL601/601-3A,-3R) and SB 604-76-004 (CL604) introducing the periodic inspection of the affected ETCG rack and pinion mechanisms (Background). Those SBs are the technical antecedents to the TLMC tasks authorised by the TRs.

• Dates: The AD carries a signature dated 27 November 2008 (James Coyne, Delegate of CASA) and it states that the AD becomes effective on 15 January 2009. The compliance requirement is "within 30 days after the effective date of this AD" and the AD is identified as 1/2009 in the header (Compliance; signature block; AD header).

• Cross-reference to foreign AD: The AD includes a note that Transport Canada AD CF-2008-32R2 dated 17 November 2008 is relevant (Requirement/Note). That connection documents the international regulatory context for this AD.

The AD therefore records a short amendment lineage: Bombardier SBs prompted TRs that introduced inspection tasks into TLMCs; CASA’s AD requires incorporation of those TLMC tasks into the Transport Canada approved Maintenance Schedule; superseded TRs are recognised as satisfactory where already complied with. The AD text does not set out further historical versions, consultation rounds, public comment, or technical differences between TRs and SBs; it confines itself to naming the effective TRs and noting the sufficiency of previous TR compliance.

The AD contains no litigation history and does not reference any judicial proceedings, appeals, or disputes. The document records safety incidents (reported incidents of throttle jam and engine shutdowns) as the factual background for the directive, but it does not refer to any litigation arising from those incidents, nor to any challenges to the AD itself.

Because the AD is limited in scope and its text does not include references to legal proceedings, there is no internal record in this instrument of administrative appeals, injunctions, or litigation. The AD’s silence on litigation should be treated as an absence of recorded legal challenge within this document rather than evidence that none exists in the wider world; however, strictly from the text provided, no litigation history is reported.

If a reader requires any judicial or tribunal outcomes relating to this AD, the AD does not supply such material; those materials would have to be obtained from case law databases, tribunal records or CASA procedural files, none of which are included in the AD text.

This AD contains a number of details and small traps for the unwary operator or maintenance manager. The AD is short, but precise; attention to wording is necessary to avoid missteps.

• Two-step compliance obligation: the AD distinguishes between an administrative compliance action (revising the Transport Canada approved Maintenance Schedule) and the operational inspections themselves. The maintenance schedule revision must be completed "within 30 days after the effective date" (Compliance), while the "initial compliance" with the new TLMC tasks is to follow the phase-in schedule in the TRs (Requirement). Some operators could mistake the 30-day period as allowing deferral of inspections; the AD separates the actions: update the approved schedule within 30 days, then conduct inspections according to the TR phase-in.

• Effective date versus AD issue date: the signature is dated 27 November 2008, but the AD becomes effective on 15 January 2009 (signature; Compliance). Counting of the 30-day compliance period is from the effective date (15 January 2009) not from the signature or issue date. Attention to that timing detail affects when the approved schedule must be revised.

• Scope is variant-specific: the AD applies only to the listed CL-600 variants: CL-600-2A12 (CL601) and CL-600-2B16 (601-3A, 601-3R & CL604) (Applicability). Operators of other CL-600 family variants are not named; applying the AD incorrectly to other variants could cause unnecessary work. Conversely, operators of the named variants must act.

• Transport Canada approved Maintenance Schedule language: the AD requires revision of the "Transport Canada approved Maintenance Schedule" (Requirement). Operators with maintenance approvals under CASA or another authority must note that the AD’s textual obligation is framed in Transport Canada terms; administrative reconciliation may be required where the operator’s approval is held under a different authority.

• Reference to Temporary Revisions and past TRs: the AD requires incorporation of tasks introduced by TR 5-236 and TR 5-2-40 but also records that prior compliance with TR 5-224 and TR 5-2-31 satisfies the AD’s intention (Requirement). Operators must confirm whether their earlier TR compliance exactly matches the inspection content required by the current TRs; the AD accepts previous compliance in principle, but the operator should be able to demonstrate which TR was adopted and when.

• Part numbers and component focus: the safety concern is narrowly identified as premature wear in the rack and pinion mechanism of ETCG P/N 2100140-005 and P/N 2100140-007 (Background). The AD focuses on inspection of those mechanisms; it does not set out physical corrective actions if wear is found, nor does it address other ETCG part numbers. Where an operator finds a variant part number, the AD does not on its face prescribe action beyond the inspection tasks embodied in the TRs and SBs.

• Reliance on Bombardier SBs and TRs for technical content: the AD does not reproduce the technical inspection criteria; it references Bombardier SB 601-0583 and SB 604-76-004 and the TRs for the phase-in schedule (Background; Requirement). Operators must consult those documents for the actual inspection procedures and phase-in details. Failure to consult the TRs/SBs could result in incomplete or incorrect inspection practice even though the approved schedule has been revised.

• No penalties specified: the AD itself does not contain penalty or enforcement provisions (Penalties and enforcement). Operators must understand that enforcement and sanction mechanisms are outside the four corners of the AD and located in the broader regulatory framework.

• Cross-jurisdictional paperwork: the AD refers to Transport Canada TRs and a Transport Canada AD. Operators under CASA jurisdiction must ensure their maintenance programme records align with the AD’s Transport Canada phrasing, and they may need to reconcile documentation across authorities.

• Documentation burden not spelled out: the AD does not define how the revision to the approved maintenance schedule should be evidenced or lodged, nor whether evidence of revision must be submitted to CASA. Operators should take care to keep clear records of the revision, the TRs used, and the timing to demonstrate compliance if asked.

These are practical friction points that arise from the AD’s precise wording, its cross-reference to TRs and SBs, and the split between administrative and operational compliance.

The AD lays out a narrow, actionable compliance pathway. To comply with the AD as written, operators and maintenance organisations should follow these steps rooted in the AD text and the documents it references.

1. Confirm applicability. Verify that the aircraft is one of the listed models: Bombardier CL-600-2A12 (CL601) or CL-600-2B16 (601-3A, 601-3R or CL604). The AD applies only to those variants (Applicability).

2. Identify the Transport Canada approved Maintenance Schedule. The AD requires revision of the "Transport Canada approved Maintenance Schedule" (Requirement). Identify the approved TLMC document relevant to the aircraft: PSP 601-5 TLMC for CL601, PSP 601A-5 TLMC for CL601-3A/3R and the CL604 TLMC for CL604.

3. Incorporate the specified TLMC tasks. Amend the approved Maintenance Schedule to include:

   • Task 76-10-00-101 in Section 5-10-30 of PSP 601-5 TLMC for CL601 (Requirement).
   • Task 76-10-00-101 in Section 5-10-30 of PSP 601A-5 TLMC for CL601-3A and CL601-3R (Requirement).
   • Task 76-11-00-101 in Section 5-10-40 of the CL604 TLMC for CL604 (Requirement).

4. Complete the administrative revision within the AD’s timeframe. The AD requires revision "within 30 days after the effective date of this AD." The AD’s effective date is 15 January 2009, therefore the schedule revision must be executed and documented within 30 days of that effective date (Compliance). Note carefully whether the operator’s internal procedures require submission of the revised schedule to an approving authority; the AD itself does not specify submission steps.

5. Follow the phase-in schedule for initial inspections. The AD directs that "Initial compliance with the above-mentioned new TLMC tasks should be carried out in accordance with the Phase‑in schedule as detailed in the applicable TRs 5-236 and TR 5-2-40." Locate and implement the phase-in schedule in TR 5-236 (for CL601 variants) and TR 5-2-40 (for CL604). This determines the timing of the first inspections following the administrative TLMC revision (Requirement; Compliance).

6. Consult Bombardier Service Bulletins for technical inspection details. The AD records that Bombardier issued SB 601-0583 (CL601/601-3A,-3R) and SB 604-76-004 (CL604) introducing the periodic inspections (Background). Use the SBs and the TRs for the precise inspection procedures, acceptance criteria, inspection intervals and any corrective actions specified by the manufacturer and adopted in the TRs.

7. Confirm whether previous TR compliance suffices. If the operator has already implemented TR 5-224 for CL601 or TR 5-2-31 for CL604, the AD states that such previous compliance "satisfies the intention of this AD" (Requirement). Document when and how the earlier TR was implemented so you can demonstrate that you meet the AD’s intention.

8. Record and retain evidence of compliance. Although the AD does not specify documentary form, retain records evidencing the revision to the approved Maintenance Schedule, the dates the revision was made, the TRs and SBs used, and the dates and outcomes of any inspections performed under the phase-in schedule. That evidence will be the operator’s primary proof of compliance.

9. Monitor for part numbers and inspection findings. The AD identifies ETCG rack and pinion P/Ns 2100140-005 and 2100140-007 as the subject of the inspections (Background). Ensure maintenance teams are aware of these P/Ns and record any findings of wear. The AD itself does not specify corrective action, so consult the Bombardier SBs and TRs for required repairs, replacements or further actions where wear is found.

10. Coordinate with regulators if necessary. The AD references Transport Canada documents and is issued by CASA. If your maintenance approvals or operations fall under multiple authorities, confirm with your accountable authority whether the revision needs to be lodged or formally approved; the AD does not specify an approval filing process.

In short, perform an administrative amendment to the Transport Canada approved Maintenance Schedule within 30 days of the AD’s effective date to insert the named TLMC tasks; execute initial inspections according to the phase-in in TRs 5-236 and 5-2-40; use Bombardier SB 601-0583 and SB 604-76-004 for inspection content; and document prior TR compliance where applicable to show you meet the AD’s intention (Requirement; Compliance; Background). The AD becomes effective 15 January 2009 and is identified as AD/CL-600/105 1/2009 (Compliance; AD header; signature).