AD/CL-600/94 - Fuel Tank Lightning Protection

The Directive directly affects a narrowly defined set of actors and indirectly touches linked parties through the maintenance and airworthiness chain.

Directly affected parties

• Aircraft owners and operators of Bombardier CL-600-2B19 aeroplanes whose serial numbers fall within the Directive’s applicability table: 7003-7067 and 7069-7929. Those operators are the legal addressees for the mandatory modification.
• Maintenance organisations and engineers tasked with performing the modification as prescribed in Bombardier SB 601R-28-055 Revision D (or an approved later revision). The work is described as internal to wing and centre fuel tanks, so maintenance personnel with appropriate licences and capabilities are implicated.
• The registered operator or maintenance organisation that holds continuing airworthiness responsibility for the affected aircraft, since continuing airworthiness obligations are the vehicle by which the Directive’s requirement will be implemented in practice.

Indirectly relevant parties

• Bombardier Aerospace as the SB issuer; the Directive depends on Bombardier’s Accomplishment Instructions and it identifies which SB revisions are acceptable.
• Transport Canada, because the Directive references Transport Canada AD CF-2007-34 and conditions acceptance of later SB revisions on approval by the Chief, Continuing Airworthiness, Transport Canada. Transport Canada’s prior actions and approval powers are therefore material to compliance choices.
• CASA, which issued the Directive (signed by its delegate), is the regulator enforcing compliance in its jurisdiction.
• Insurers and lessors who hold operational or contractual rights in the affected aircraft: the Directive imposes a retrofit requirement that may be relevant to contractual warranties, leasing covenants, fitness-for-purpose obligations and insurance underwriting, though none of these legal relationships are set out in the text.

Who does not appear to be affected

• Aircraft with serial number 7068 are omitted from the listed ranges. The papered applicability expressly includes 7003-7067 and 7069-7929; the omission of 7068 means that serial 7068 is not covered by the Directive as published. The Directive does not explain that omission in the text provided.
• Airframes of models other than CL-600-2B19 are outside scope.

Who bears direct economic cost

• The Directive itself does not state who pays, but the legal addressees (owners/operators and the appointed maintenance organisations) will be responsible for carrying out the work. In practice, the operator as the continuing airworthiness duty-holder will incur direct costs (labour, parts, aircraft downtime, and any need to secure approved data), because the Directive imposes an obligation on those parties to make the specified modification within the set compliance window.

Decision-makers and approvals

• CASA (through its delegate) is the issuing authority and will determine enforcement steps for non-compliance in its jurisdictional processes, though the Directive text does not set out those enforcement measures.
• The Chief, Continuing Airworthiness, Transport Canada is the approving authority for any later SB revisions that an operator might rely on instead of Revision D.

Duties imposed by the Directive

• Modify certain bonding jumpers inside the wing and centre fuel tanks, strictly "according to the Accomplishment Instructions of Bombardier Service Bulletin (SB) 601R-28-055, Revision D, dated 17 July 2006," or a later revision of the SB only if that later revision is approved by the Chief, Continuing Airworthiness, Transport Canada. The SB’s Accomplishment Instructions are the prescriptive technical method for compliance.
• Achieve the modification within a fixed compliance period: "within 5000 hours time in service after the effective date of this Directive." The effective date is 13 March 2008, so the compliance clock starts from that date.
• Observe the Directive’s applicability: only airframes listed by serial number are captured and therefore only they carry the mandatory duty.

Rights and conditional allowances

• Operators may rely on later revisions of the SB if and only if those later revisions are approved by the Chief, Continuing Airworthiness, Transport Canada. This creates a procedural right to use updated instructions, but it is conditioned on external approval.
• Operators are not permitted to rely on the original, Revision A, or Revision B of the SB to satisfy this Directive, per Note 1. That information is normative: the Directive expressly disqualifies certain previously existing technical solutions.
• The Directive does not itself provide express rights to exemptions, deferred compliance or alternative means of compliance within the published text; any such relief would have to be sought through the regulator’s ordinary administrative processes (not set out in the Directive).

Normative chain of instructions

• The Directive converts a manufacturer’s SB into a regulatory requirement by reference; this means that compliance is measured against the SB’s Accomplishment Instructions as of Revision D, or other revisions as approved. The SB text is the operative technical standard.

Documentation and proof

• While the Directive text does not specify record-keeping requirements, the requirement to comply "within 5000 hours time in service" implies the need for operators to measure and record aircraft hours and to be able to demonstrate that the modification was completed within the required window. The Directive itself does not state the form of evidence required.

Scope limits and exclusions

• The Directive applies only to the listed serial-number ranges and only to the CL-600-2B19 model. The exclusion of serial 7068 is explicit in the listing; no textual mechanism in the Directive allows operators of excluded serial numbers to assume coverage.

Interplay with foreign approvals

• The Directive places an element of choice under the control of Transport Canada: later SB revisions are only acceptable if specifically approved by the Chief, Continuing Airworthiness, Transport Canada. That means operators seeking to use a later SB revision must secure that approval before relying on it for compliance.

The Directive text supplied does not specify any penalty regime, monetary fines, suspension mechanisms, or criminal sanctions. It establishes a mandatory requirement (a retrofit) with a defined compliance period but does not set out the enforcement tools or penalties available for failure to comply within the published text.

What the document does make clear

• It is a regulatory instrument issued by the Civil Aviation Safety Authority (CASA), signed by the delegate, and therefore it is an enforceable airworthiness directive within the issuing jurisdiction by virtue of its regulatory status. The Directive states the requirement and effective date and is intended to correct an unsafe condition via mandatory modification.

What the document does not say

• The Directive does not describe inspection, certification sign-off, or documentary proof required to show compliance. It does not set out a penalty tariff (deprivation, fine, or other sanction) for non-compliance. It does not describe remedial steps that CASA would take if compliance is not achieved within the 5,000-hours window.

Practical enforcement implications (as implied by the instrument’s form)

• Because the Directive makes compliance mandatory for the specified aircraft, the typical practical enforcement measures that regulators exercise in comparable settings would be: grounded aircraft until compliance is demonstrated, suspension of operations or airworthiness certificate action until the AD is complied with, or administrative enforcement action; however the Directive text itself does not spell these out. Readers should note that the Directive creates a continuing airworthiness obligation that is legally enforceable through the regulator’s general powers even if those powers and remedies are not listed in the Directive text.

Interaction with approvals and international ADs

• The Directive references Transport Canada AD CF-2007-34 and conditions the acceptance of later SB revisions on approval by the Chief, Continuing Airworthiness, Transport Canada. This indicates that enforcement and compliance may be monitored against Transport Canada’s actions where those overlap, but the Directive itself does not prescribe cross-jurisdictional enforcement mechanics.

Record and audit risk

• Even in the absence of specified penalties within the Directive text, operators should expect that failure to comply could be identified during regulatory surveillance, airworthiness reviews, or accident investigations. The Directive’s prescriptive nature about method (SB Revision D or later TC-approved revisions) and timeframe means that proving non-compliance is administratively straightforward: check serial number, check modification records, check hours-in-service at time of work.

The Directive makes explicit textual connections to other regulatory material and to decisions by another national authority, and those cross-references shape permissible compliance paths.

References to Transport Canada materials

• The Background states that Bombardier completed a system safety review of the CL-600-2B19 fuel system "against new fuel tank safety standards, introduced in Chapter 525 of the Airworthiness Manual through Notice of Proposed Amendment (NPA)2002-043." The Directive notes that identified non-compliances were assessed using "Transport Canada Policy Letter No. 525-001 to determine if mandatory corrective action is required." The Directive also includes Note 2: "Transport Canada AD CF-2007-34 refers." These explicit references mean the Directive’s technical and policy framing derives in part from Transport Canada’s airworthiness standards and policy materials.
• The Directive conditions acceptance of later SB revisions on approval by the Chief, Continuing Airworthiness, Transport Canada. That gives Transport Canada a gatekeeping role over whether an operator may substitute a later SB revision for Revision D.

Incorporation by reference and manufacturer data

• The Directive makes the Bombardier Service Bulletin the operative technical instrument for compliance: operators are required to "modify bonding jumpers ... according to the Accomplishment Instructions of Bombardier Service Bulletin ... Revision D ... or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada." That is a standard regulatory technique where a manufacturer’s instructions are incorporated by reference into a mandatory regulatory requirement. The legal effect is to elevate the SB’s technical instructions to a regulatory duty, but only the specified versions are acceptable unless Transport Canada approves later changes.

Regulatory harmonisation and duplication

• By cross-referencing and aligning with Transport Canada’s AD and policy, the Directive shows an intent to harmonise corrective action across jurisdictions for the CL-600-2B19. The Directive does not, however, explain how conflicts between CASA and Transport Canada directions would be resolved; it simply references and conditions compliance on Transport Canada approvals.

Absence of stated interaction with domestic aviation statutes or penalties

• The Directive does not recite or quote enabling statutory provisions from the domestic Civil Aviation Act or regulations that grant CASA enforcement powers or authority to issue ADs; such enabling material may exist in the broader regulatory framework, but it is not included in this text. The Directive therefore should be read together with the regulator’s primary enabling statutes and enforcement instruments for the full legal mechanics.

Technical standard setting and international influence

• The Background notes the role of "new fuel tank safety standards" introduced in an Airworthiness Manual via a Notice of Proposed Amendment. This ties the Directive to an international- or national-level standard-setting process that informed the safety assessment underpinning the AD. The Directive itself is the domestic regulatory instrument that implements the required corrective action derived from that standard-setting exercise.

Practical consequence for operators with international operations

• Operators who fly these serial-numbered aeroplanes between jurisdictions will need to comply with this CASA AD and also take account of the referenced Transport Canada AD. Where Transport Canada approves a later SB revision, CASA’s text allows operators to use that revision for compliance only if Transport Canada has approved it, thereby tying an element of domestic compliance to a foreign regulator’s approval decision.

This Directive’s amendment history as reflected in the supplied text is limited to a few discrete points concerning the service bulletin and the Directive’s dates.

Key temporal and revision points recorded in the text

• The Directive states that the required modification must be performed "according to the Accomplishment Instructions of Bombardier Service Bulletin (SB) 601R-28-055, Revision D, dated 17 July 2006." Revision D of the SB is the baseline version that the Directive references.
• Note 1 explicitly disqualifies compliance based on the original issue, Revision A or Revision B of the SB: "Modification of bonding jumpers according to the original issue, Revision A or Revision B of the above noted SB DOES NOT satisfy the requirements of this Directive." The Directive thus amends acceptable compliance methods by excluding earlier SB versions.
• The Directive leaves open the possibility of later SB revisions being acceptable, but only if such later revisions are "approved by the Chief, Continuing Airworthiness, Transport Canada." In other words, the Directive allows amendment of the operative technical method by later approved SB revisions, subject to a named authority’s approval.
• Effective date and administrative dates: the Directive "becomes effective on 13 March 2008." The signature block shows the Directive as dated 21 January 2008 (signed by Charles Lenarcic, Delegate of CASA). The tabulated header lists "3/2008" as the date line, consistent with March 2008 issuance, while the signature date and effective date indicate a formal lead time between signing and effectiveness.

What the text does not contain about amendments

• The Directive does not record any amendments to its own text after the effective date. It does not include a history table of revisions to the Directive itself (no later AD numbers, supersessions, or cancellations appear in the supplied text).
• The Directive does not set out a process by which operators can apply for an alternative means of compliance (AMOC) or request time extensions; it simply states the requirement and compliance window and leaves any such administrative mechanisms to wider regulatory practice (not described in the text).

Operational consequence of the SB revision rule

• The treatment of different SB revisions in the Directive constitutes the principal mechanism for future amendment of the technical requirement without reissuing the AD: a later SB revision may become acceptable if the named Transport Canada official approves it. This creates an asymmetry: CASA sets the AD, but acceptance of alternative technical data depends on Transport Canada approval.

The supplied text contains no litigation history. It names no legal proceedings, case law, appeals, or precedent related to this Directive. The document does cross-refer to Transport Canada AD CF-2007-34 and to Transport Canada policy instruments and the Airworthiness Manual’s Notice of Proposed Amendment NPA2002-043; however, none of these references are accompanied by litigation records in the provided material.

What the absence means for practitioners

• There is no case law supplied that interprets this Directive’s scope, enforcement, or the binding nature of incorporated SB instructions. Practitioners should therefore treat the Directive as an executed regulatory instrument without recorded judicial interpretation in this text.
• Any legal questions about enforcement, evidentiary standards for compliance, or contestation of the Directive’s technical content would require reference to other materials (regulatory enforcement procedures, administrative appeal routes, or judicial decisions) not included in this Directive transcript.

Recommended immediate actions if litigation risk is a concern

• Because this text does not provide litigation outcomes, affected parties who are concerned about enforceability, the validity of the Directive, or potential defences should seek the regulator’s compliance guidance and preserve documentary evidence of any remedial steps. The Directive’s clear technical prescription and defined compliance window mean that disputes about non-compliance would likely turn on factual proof of whether the modification was carried out as required and within the 5,000-hours window; however the Directive itself does not supply dispute-resolution or appeals information.

This Directive contains several technical, temporal and drafting particulars that can lead to misunderstandings or operational risk if not noticed.

Serial number omission

• The applicability lists serial numbers 7003 through 7067, and 7069 through 7929. Serial number 7068 is not included. The Directive does not explain this exclusion. Practitioners must not assume serial 7068 is covered; the plain wording shows it is not. Failure to check serial numbers precisely could lead to unnecessary work or, conversely, to missing an obligation.

Strictness about acceptable SB revisions

• The Directive mandates compliance "according to the Accomplishment Instructions of Bombardier Service Bulletin ... Revision D ... or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada." Note 1 explicitly forbids using the original issue, Revision A or Revision B as satisfying the Directive. That is a strict exclusion that can catch operators who assume earlier or original SBs are acceptable. Only Revision D or Transport Canada-approved later revisions are acceptable.

Dependency on another regulator for later revisions

• Although the Directive is issued by CASA, it conditions acceptance of later SB revisions on approval by the Chief, Continuing Airworthiness, Transport Canada. That creates a dependency: if an operator wants to rely on a later SB revision for compliance, they must secure approval from a foreign regulator (Transport Canada) as explicitly stated. That may introduce administrative delays or uncertainty.

Clocked compliance: hours-in-service metric

• The compliance obligation is time-limited and measured in time in service: "within 5000 hours time in service after the effective date of this Directive." The effective date is 13 March 2008. Operators must accurately track aircraft hours and anticipate scheduling for maintenance without relying on calendar days alone. If the aircraft is in frequent service, 5,000 hours could be reached sooner than expected; conversely, if stored, it could be later. Misreading the compliance metric as calendar time instead of hours-in-service is a common operational pitfall.

Ambiguity on enforcement and documentation

• The Directive does not specify the nature of documentary proof required to demonstrate compliance (for example, entries in maintenance records, certificate of release to service, or AD compliance records). Without explicit instructions, operators must choose conservative record-keeping to be able to prove compliance if queried by the regulator.

Work scope inside fuel tanks

• The modification is specified as occurring "inside the wing and centre fuel tanks," which implies confined-space work on fuel system components. The Directive does not describe the ancillary maintenance actions necessary to create safe access (draining/venting, cleaning, protective procedures, testing). Maintenance organisations must ensure that the repair scope needed to implement the SB is accounted for in planning and that appropriate approvals and safety procedures are in place, because the Directive requires the result but does not specify the operational steps to get there beyond the SB instructions.

Reference to Transport Canada AD and policy

• Note 2 refers to Transport Canada AD CF-2007-34 and the Background cites Transport Canada Policy Letter No. 525-001 and NPA2002-043. Operators and maintenance organisations should not ignore these cross-references as they inform the safety framing and may contain parallel requirements or guidance. The Directive does not reproduce their content.

Effective date vs signature date

• The signature block shows a date of 21 January 2008 while the effective date is 13 March 2008. The advance window between signing and effectiveness is a scheduling detail; operators should base compliance counting on the effective date, not the signature date. Miscounting could cause inadvertent non-compliance.

No penalties or procedures in the text

• The Directive contains no textual prescription of penalties, remediation steps, or the process for seeking an alternative means of compliance or an extension. Operators who rely on administrative remedies or who anticipate difficulty in meeting the 5,000-hours deadline should proactively engage the regulator (CASA) to seek documented relief, rather than assume such procedures exist simply because they are common elsewhere.

The Directive sets a limited, concrete compliance pathway. The following steps are grounded in the Directive’s content and practical interpretation of its requirements.

1. Verify applicability precisely

   • Check the aircraft model and serial number against the Directive’s applicability list: CL-600-2B19 aircraft, serial numbers 7003-7067 and 7069-7929. Do not assume inclusion; notably, serial number 7068 is not listed and therefore not subject to this AD as published.

2. Confirm the effective date and compliance window

   • The Directive becomes effective on 13 March 2008. The required modification must be completed within 5,000 hours time in service after that effective date. Start the compliance clock from the effective date and calculate remaining hours-in-service allowance for each affected airframe.

3. Obtain and use the correct technical data

   • Acquire Bombardier Service Bulletin (SB) 601R-28-055 Revision D, dated 17 July 2006, and its Accomplishment Instructions; Revision D is the baseline prescriptive document for compliance.
   • Do not rely on the SB’s original issue, Revision A or Revision B to satisfy the Directive , Note 1 disqualifies these earlier versions.
   • If considering using a later SB revision, obtain documented approval from the Chief, Continuing Airworthiness, Transport Canada before relying on that later revision for compliance, because the Directive only permits later revisions with that approval.

4. Plan the maintenance task in operational terms

   • The Directive requires modification "inside the wing and centre fuel tanks." Plan for the work scope implied by tank interior access (e.g., draining, establishment of safe maintenance conditions, qualified personnel, and appropriate tooling), and ensure maintenance organisation capability and licensing are appropriate to perform in-tank electrical bonding modification as described in the SB. The Directive itself does not list ancillary procedures, so follow the SB’s Accomplishment Instructions and applicable maintenance regulations.

5. Schedule within the 5,000-hours window

   • Book the aircraft into a maintenance slot so that the modification is completed and documented before the aircraft accumulates 5,000 hours time in service from 13 March 2008. Where aircraft hours accumulate rapidly, do not assume calendar time will be sufficient.

6. Coordinate approvals where necessary

   • If you intend to use a later SB revision, lodge any necessary documentation or requests with the Chief, Continuing Airworthiness, Transport Canada to secure approval before performing the modification to that later revision standard. Keep the approval documentation linked to the aircraft’s maintenance records.

7. Record completion and retain evidence

   • Although the Directive does not prescribe a specific form of compliance evidence, maintain clear records that demonstrate:
     • The aircraft serial number and identification;
     • The date and aircraft hours at which the modification was carried out;
     • The SB revision used (Revision D or later TC-approved revision) and the relevant Accomplishment Instruction references;
     • Maintenance organisation authorising signatures and certificates of release to service where applicable.
   • These records will be the primary evidence to show compliance during regulator inquiries or audits.

8. Review Transport Canada cross-references

   • Note 2 refers to Transport Canada AD CF-2007-34, and the Background references Transport Canada policy instruments and Chapter 525 changes. Check whether Transport Canada publications contain complementary instructions, approvals, or clarifications relevant to the modification and to any approvals you may seek.

9. Engage CASA where necessary

   • If circumstances make timely compliance difficult, or if an alternative means of compliance is being considered, engage CASA early to request guidance or documented relief. The Directive text does not detail administrative relief mechanisms, so a documented regulatory engagement reduces risk.

10. Plan for operational impacts and cost

    • The Directive requires work inside fuel tanks and therefore will take maintenance time and resources. Plan for aircraft downtime, potential need for parts, qualified labour, and any testing required post-modification. Contractual parties (lessors, insurers, third-party maintenance providers) should be informed so responsibilities for costs and scheduling are allocated in practice; the Directive itself does not assign financial responsibility.

11. Verify no duplication or contradiction

    • Because the Directive references Transport Canada AD CF-2007-34, ensure that compliance steps do not conflict with any parallel AD or international requirement. Where divergent instructions exist, secure guidance from CASA and, if needed, Transport Canada.

12. Retain an audit trail for future inspections

    • Keep the maintenance records available for any CASA inspection, for transfer of aircraft ownership, or for operational audits. While the Directive does not specify documentation format, keeping a clear, auditable file with SB pages, signed worksheets, and hours counters will substantiate compliance.

Following these steps aligns practical maintenance planning and record-keeping with the Directive’s letter: use Revision D of Bombardier SB 601R-28-055 (or a later Transport Canada-approved revision), complete the modification inside wing and centre fuel tanks, and do so within 5,000 hours time in service from 13 March 2008, for the explicitly listed serial-numbered aeroplanes.