AD/BELL 206/168 - Upper Left Hand Tailboom Attachment

The Directive rests on a small number of core concepts and references that determine scope and action:

• Applicability is functionally model-limited and part-number specific. The AD applies only to specified Bell 206 and Agusta Bell 206 variants and only to helicopters that have the specific CRES steel fitting identified as part number 407-030-750-103 installed at the upper left hand tailboom attachment. The “Applicability” line explicitly enumerates the models and the Requirement refers to part number 407-030-750-103.

• Inspection-first approach. The AD does not mandate immediate blanket replacement of bolts across the fleet. It requires an initial inspection and correction of washer installation where applicable (Requirement: Part I of Alert Service Bulletin 206-06-110 or 206L-06-140). Replacement is required only “as a result of the bolt inspection” (Requirement step 1 and the subsequent instruction: “If replacement is necessary as a result of the bolt inspection, proceed as follows: 2. Replace...”).

• Use of manufacturer Alert Service Bulletins as normative sources. The substantive procedures for inspection, correction, and replacement are to be performed “in accordance with Part I” and “Part II” of the named Bell Helicopter Textron Canada Alert Service Bulletins, or later Transport Canada approved revisions. The AD therefore adopts the SBs (and their later Transport Canada approved revisions) as the procedural norm.

• Torque verification requirement. Independent of replacement, the Directive mandates a torque check performed in accordance with the applicable maintenance manual: Requirement step 3. The compliance timetable sequences the torque checks relative to the inspection/replacement milestones (Compliance).

• Temporal compliance windows and sequencing. The AD sets a short initial inspection window , within 50 hours time in service after 10 May 2007 unless already done , then ties subsequent torque checks to the next scheduled 100-hour or annual inspection, and requires a torque check at the next scheduled 100-hour after any bolt replacement. The AD also states an effective date (7 June 2007). The Compliance wording is explicit and time-sequenced.

• Cross-jurisdictional reference. The AD notes that Transport Canada AD CF-2007-01 refers, indicating parallel or related regulatory action by the Canadian authority. The AD text includes a direct admonition: “Note: Transport Canada AD CF-2007-01 refers.”

These concepts determine the operator’s practical choices: confirm whether the specified part is installed, follow the manufacturer’s Alert SB for inspection and corrective work, and schedule torque checks within the AD’s windows. The AD frames the procedures by reference rather than by reproducing step-by-step technical instructions, so compliance requires access to the specified Alert Service Bulletin and the applicable maintenance manual.

The AD places obligations and operational impacts on a small set of clearly identified actors. The instrument’s Applicability, Requirement and Compliance sections together define who must act.

• Registered operators and owners of the listed helicopter models that have the specified CRES fitting installed. The Applicability line names Model 206A, 206B, 206L, 206L-1, 206L-3 and 206L-4 helicopters. The Requirement conditions its operative obligations on the presence of the CRES steel fitting, part number 407-030-750-103, at the upper left hand tailboom attachment. Therefore only those operators whose airframes actually have that fitting installed are required by this AD to undertake the mandated inspections and work.

• Maintenance organisations and licensed maintenance engineers. The AD requires inspection, washer correction, bolt replacement (if required) and torque checks “in accordance with” specified Alert Service Bulletins and the applicable maintenance manual. That work will typically be carried out by certificated aircraft maintenance engineers or repair organisations that hold the necessary approvals to perform the procedures referenced in the Bell Alert Service Bulletins and the aircraft’s maintenance manual. The instrument’s reliance on the SBs and the maintenance manual makes those service documents operationally central.

• Parts and supply chain participants. Where bolt replacement is required per Part II of the Alert Service Bulletin, operators will source compliant replacement bolts and ensure the installation follows the SB. Suppliers of parts (bolts, washers, fittings) will therefore be engaged. The AD specifically singles out the CRES fitting part number as the locus of potential non-conformity, so any organisation maintaining inventory records needs to be able to identify that part number.

• Regulators and delegates. The AD is issued by the Civil Aviation Safety Authority (CASA) and signed by a Delegate (David Villiers). The document names a related Transport Canada AD (CF-2007-01), indicating that both CASA and Transport Canada are engaged with the unsafe condition identified. CASA’s effective date (7 June 2007) sets the enforcement commencement.

• Airworthiness authorities and compliance auditors. Organisations charged with continuing airworthiness oversight will use the AD to check maintenance records for the required inspections, any replacement events under Part II, and the torque checks performed at the scheduled inspections.

Who pays. The document itself does not state who bears the financial cost, but the nature of ADs implies that the owner/operator must arrange and pay for the inspections, any corrective actions, and part replacements. The Requirement makes replacement conditional on the bolt inspection outcome, creating a cost uncertainty that operators must manage.

Who decides. Operators decide whether a helicopter has the specified fitting, arrange the inspection as required by the AD, and, where the inspection reveals non-conformance, implement the bolt replacement in accordance with Part II of the Alert Service Bulletin. Maintenance personnel follow the SB procedures and the maintenance manual torque check specifications; CASA enforces compliance from the stated effective date.

This section extracts the operative duties created by the AD and the practical rights implied within the document.

Duties (expressed in the AD):

• Determine applicability on the airframe. Operators must “determine if the upper left hand tailboom attachment fitting is a CRES steel fitting, part number 407-030-750-103.” This is the threshold duty before any further AD obligations apply (Requirement: step 1).

• Inspect bolt and correct washer installation where a CRES fitting is fitted. If the specified CRES fitting is installed, operators must inspect the bolt and, if required, “correct the washer installation in accordance with Part I of Bell Helicopter Textron Canada Alert Service Bulletin 206-06-110 or 206L-06-140, as applicable; or later Transport Canada approved revisions.” This is an affirmative procedural duty tied to a specific manufacturer document.

• Replace bolt if inspection indicates necessity. The AD requires replacement “if replacement is necessary as a result of the bolt inspection” and mandates the replacement be performed “in accordance with Part II of Bell Helicopter Textron Canada Alert Service Bulletin 206-06-110 or 206L-06-140, as applicable; or later Transport Canada approved revisions.”

• Perform torque checks. The AD requires a torque check “of the upper left hand tailboom attaching hardware in accordance with the applicable maintenance manual.” The compliance timeline ties this torque check to either the next scheduled 100-hour or the next annual inspection, and a further torque check after any replacement at the next scheduled 100-hour.

• Adhere to compliance timing. Operators must meet the specific time windows: the initial inspection within 50 hours time in service after 10 May 2007 unless already done; the torque check at next scheduled 100-hour or annual inspection after Part I; and torque check at next scheduled 100-hour after bolt replacement (Compliance).

Rights and procedural implications (as drawn from the AD):

• Use of later Transport Canada approved revisions of the Alert Service Bulletins. The AD expressly allows the procedures to be carried out in accordance with the named SBs “or later Transport Canada approved revisions.” That gives operators the right to rely on a later Transport Canada approved revision of the SB, without requiring a new CASA AD, provided that revision is in fact approved by Transport Canada.

• No immediate blanket replacement mandated. The AD’s inspection-first framework gives operators the procedural right to avoid unnecessary bolt replacement if the initial inspection shows the bolt meets design criteria. Replacement is not mandated unless the inspection produces a finding that triggers Part II. That sequencing preserves operator discretion to act proportionately to the physical condition found.

• Reliance on the maintenance manual for torque checks. The AD delegates the technical specification for torque verification to the “applicable maintenance manual,” which means operators implement torque checks according to their approved maintenance documentation for the helicopter.

• Cross-reference to Transport Canada AD. The “Note: Transport Canada AD CF-2007-01 refers” gives operators an explicit pointer to a related authority’s AD, which may be used for procedural parity or to source the Alert Service Bulletin revisions. The AD thus recognises parallel regulatory material.

Operative constraints embedded in the AD:

• The AD’s duties are conditional. The initial duty to act applies only “if a CRES fitting is installed.” Operators who determine the fitting is not the specified CRES part number do not incur the inspection/replacement obligations.

• Document reliance. The AD requires compliance with specific Alert Service Bulletins and the applicable maintenance manual; failure to have or follow those documents would impede lawful compliance.

• Time-limited corrective sequencing. The short initial window (50 hours time in service after 10 May 2007) compresses the time for operators to check records, identify affected helicopters, and schedule the required maintenance.

The AD does not specify exemptions, alternative means of compliance, or any administrative appeal procedure in the text. It does, however, allow the use of “later Transport Canada approved revisions” of the specified Alert Service Bulletins.

The AD text provides a clear effective date and sets mandatory compliance timings, but it does not in itself set out statutory penalties or enforcement mechanisms in the text provided. The document does, however, contain features that produce enforceable obligations for affected aircraft operating under CASA’s regulatory regime.

What the document states about enforcement mechanics:

• Effective date and signature. The AD “becomes effective on 7 June 2007” and is signed by a Delegate of the Civil Aviation Safety Authority (David Villiers). The signature and effective date indicate the AD is an instrument of the regulator and therefore part of the enforceable airworthiness regime. The AD’s Compliance section ties specified actions to concrete inspection and maintenance events.

• Mandatory compliance timings. The AD sets specific compliance windows (within 50 hours time in service after 10 May 2007; at the next scheduled 100-hour or annual inspection; and at the next scheduled 100-hour inspection after bolt replacement). The presence of these timelines signals obligations that CASA would expect to be met and recorded in maintenance logs.

What the AD does not state in this text:

• No penalty schedule. The instrument does not specify particular monetary penalties, licence sanctions, or criminal sanctions in its text. The AD itself is silent on exact enforcement consequences for non-compliance.

• No administrative appeal process. The document does not describe a mechanism for seeking relief, alternative methods of compliance, or appeal within the AD text. It does, however, allow use of “later Transport Canada approved revisions” of the Alert Service Bulletins, which is a permissive clause rather than an appeal procedure.

Practical enforcement implications (based on the AD wording):

• Record-based enforcement. Given the AD’s procedural requirements and specific timing markers tied to scheduled inspections and time-in-service counters, enforcement will be practicable through review of maintenance records. The AD’s obligations , inspections, corrections, replacements, torque checks , generate maintenance entries that CASA auditors or inspectors can examine to confirm compliance.

• Interaction with other regulators. The AD notes Transport Canada AD CF-2007-01 as referring. Where an aircraft is subject to oversight by multiple authorities (for example, through maintenance approvals or cross-border operations), regulators may reference each other’s ADs in enforcing continuing airworthiness. The AD’s reference to a Transport Canada AD indicates an expectation of aligned international action.

• Delegated enforcement authority. The AD is signed by a CASA Delegate, which indicates delegated administrative authority within the regulator to issue ADs. Enforcement would proceed under CASA’s broader statutory powers rather than within the AD text itself.

Operators should therefore treat the AD’s obligations as binding requirements from the regulator and expect that failure to document compliance in the maintenance logbooks and records, after the effective date, would expose them to regulatory follow-up by CASA. The AD does not, in itself, state the penalties for non-compliance; the instrument’s force derives from its regulatory provenance and its instruction to follow approved service documents.

The AD explicitly cross-references and incorporates materials from other aviation safety instruments and documentation; its operation is therefore interlinked with other regulatory and manufacturer sources listed in the text.

Express cross-references in the AD:

• Transport Canada AD CF-2007-01. The AD contains the concise note: “Note: Transport Canada AD CF-2007-01 refers.” That language indicates the CASA AD recognises a related regulator’s directive and invites operators and maintainers to consider Transport Canada’s AD as relevant material. The AD also allows procedures “or later Transport Canada approved revisions” of the Bell Alert Service Bulletins as acceptable reference documents.

• Bell Helicopter Textron Canada Alert Service Bulletins. The AD requires that inspection, washer correction, and bolt replacement be done “in accordance with Part I” and “Part II” of the Bell Helicopter Textron Canada Alert Service Bulletin 206-06-110 or 206L-06-140, as applicable. By incorporating those SBs by reference, the AD integrates manufacturer-issued technical instructions into the regulatory requirement. The AD thus depends on the content and any approved revisions of those SBs.

• The applicable maintenance manual. The AD mandates torque checks in “accordance with the applicable maintenance manual,” which places the helicopter’s approved maintenance documentation within the compliance chain. The maintenance manual is therefore a legally operative source for the technical specifications of the torque check.

How the AD’s cross-references affect regulatory interactions and compliance choices:

• Incorporation by reference means technical standards are not reproduced. Operators must obtain the named SBs and the maintenance manual and must ensure they are following the versions permitted by the AD (“or later Transport Canada approved revisions”). Because the AD does not reproduce the SB content, access to those documents is necessary to satisfy the AD’s procedural duties.

• Parallel international action. The explicit mention of a Transport Canada AD indicates that CASA’s AD is part of a pattern of action addressing an unsafe condition across jurisdictions. Where Transport Canada has approved revisions to the SBs, the AD permits those later revisions to be used, subject to Transport Canada approval, which shows a cross-jurisdictional delegation of technical detail.

• Practical effect on airworthiness regulation. The AD functions as a regulatory instrument that ties manufacturer procedures and maintenance manual instructions into the mandatory continuing airworthiness regime administered by CASA. Compliance will be assessed against the AD’s requirements as implemented via the SBs and maintenance manual.

What the AD does not reference in this text:

• The AD does not explicitly mention specific domestic statutes, penalty provisions, or the regulatory instrument under which CASA issued the AD. The document is an AD in form and signed by a CASA Delegate, but the textual content does not include references to enabling legislation or to civil or criminal sanctions.

• The AD does not reference international agreements or ICAO standards. Its only cross-national reference is the Transport Canada AD.

Overall, the AD integrates manufacturer instructions (the Bell Alert Service Bulletins) and the relevant maintenance manual into CASA’s enforceable continuing airworthiness directive, while explicitly acknowledging a related Transport Canada AD and permitting later Transport Canada approved SB revisions to be used for compliance.

The text provided contains no formal amendment history entries and does not list prior or subsequent amendments to this AD. The document itself contains language that allows for the use of later Transport Canada approved revisions of the referenced Alert Service Bulletins, but it does not record any amendments to the AD text itself.

What the AD says about revisions and updates:

• Use of later Transport Canada approved revisions. The Requirement repeatedly qualifies the procedural obligations by permitting the work to be performed “in accordance with Part I ... or later Transport Canada approved revisions” and similarly for Part II. That permissive language shows the AD was drafted to accept subsequent, Transport Canada approved technical revisions to the Alert Service Bulletins without the need for immediate amendment to the AD text.

• Effective date and initial issuance. The AD states it “becomes effective on 7 June 2007” and the document is dated 24 April 2007 (signed by the CASA Delegate). Those entries identify the AD’s initial operative timeline and issuance date.

Absence of recorded amendments in the document:

• No revisions, superseding AD, or cancellation appears in the text provided. There is no section titled “Amendment” or listing of prior AD numbers that this instrument replaces. The AD does not include later dates or version numbers beyond the effective date.

• The AD refers to Transport Canada AD CF-2007-01 but does not record whether the CAS A AD has been amended in response to Transport Canada action; the AD’s text merely directs readers to that related AD.

Operational takeaways from the absence of a recorded amendment history within the AD text:

• Operators should treat the AD as a static instrument effective from 7 June 2007, unless and until CASA issues a further AD, amendment or cancellation. Because the AD allows the use of later Transport Canada approved SB revisions, operators must monitor Transport Canada approvals of those SBs for changes relevant to compliance.

• Maintenance and continuing airworthiness records should reflect compliance with the AD as worded at the effective date, with the procedural flexibility to use later Transport Canada approved SB revisions if applicable. If CASA later amends or supersedes the AD, operators would be required to follow the subsequent instrument.

• The AD’s lack of an internal amendment log means that to determine whether the AD has been amended after the document’s effective date one must consult CASA’s current AD database or regulatory publications, because the text here does not supply that history.

In short, this AD’s document contains no internal amendment history entries; it establishes an effective date, and it explicitly allows reliance on later Transport Canada approved SB revisions for the procedural tasks it requires.

The document contains no litigation history, judicial references, or citations to cases. The AD is an administrative safety directive issued by CASA and signed by a Delegate (David Villiers) on 24 April 2007, with an effective date of 7 June 2007. The text does not record any challenges, judicial review actions, or litigation outcomes relating to this AD.

What can be read directly from the document:

• No cases or legal proceedings are named. The AD’s text and tables do not mention any court proceedings, appeals, or the outcome of any legal disputes.

• Administrative provenance only. The AD is presented as a regulatory safety action, referencing manufacturer-determined unsafe condition and a related Transport Canada AD (CF-2007-01). The signature by a CASA Delegate shows it is an administrative instrument rather than a judicial pronouncement.

Consequences of the absence of litigation history in this text:

• The AD itself provides no record of any judicial engagement. If an interested party wants the litigation or review history of this AD, that is not contained in the AD document supplied. Such a researcher would need to check external records (judicial registries, CASA enforcement files or public notices) to determine whether the AD was subject to legal challenge or review. The AD does not supply that data.

• The lack of litigation references does not in itself speak to the legality or enforceability of the AD; it merely indicates that the AD text supplied does not record any litigation or legal challenges.

Because the instruction for this deep dive is to rely solely on the supplied source, this section must report the absence of litigation history in the instrument and cannot posit litigation outcomes or disputes not present in the AD text.

This AD contains several practical and procedural features that can create traps for operators and maintenance organisations if not carefully managed. These items are pulled directly from the AD’s wording and the logical consequences of its sequencing.

1. Applicability depends on a specific part number. The AD applies only where the upper left hand tailboom attachment fitting is a CRES steel fitting, part number 407-030-750-103. Failure to identify the exact part number on the airframe may lead to either unnecessary compliance work or missed obligations. The AD’s Applicability section is explicit: operators must determine whether that specific fitting is installed before proceeding.

2. Inspection-first sequencing. The AD does not require automatic replacement. The bolt replacement is conditional: “If replacement is necessary as a result of the bolt inspection, proceed as follows: 2. Replace the upper left hand bolt...” Operators who assume replacement is mandatory may incur unnecessary expense; operators who skip the inspection step risk non-compliance.

3. Multiple documents required to comply. The AD requires compliance “in accordance with Part I” and “Part II” of the Bell Alert Service Bulletins and “in accordance with the applicable maintenance manual.” The AD does not reproduce those procedures. Operators who do not have immediate access to the named Alert Service Bulletins (206-06-110 or 206L-06-140) or to the applicable maintenance manual may be unable to complete compliant work. The AD’s Requirement section explicitly cross-references those documents.

4. Timing windows anchored to a calendar date and to scheduled inspections. The initial inspection must be completed “within 50 hours time in service after 10 May 2007, unless already accomplished.” The AD therefore creates a compliance window referenced to 10 May 2007 rather than to the AD effective date (7 June 2007). Operators must track hours time in service from that specified date. Additionally, torque checks are tied to the “next scheduled 100-hour inspection or annual inspection, whichever occurs first; following accomplishment of Part I” and to the “next scheduled 100-hour inspection following bolt replacement.” Misunderstanding these sequencing rules could cause late torque checks.

5. Torque checks follow inspections and replacements at different scheduled events. The AD requires torque verification both after Part I at the next scheduled 100-hour or annual inspection and again at the next scheduled 100-hour inspection after any bolt replacement. Operators must ensure they log the initial Part I date and subsequent replacement date to identify the correct next inspection that triggers torque verification.

6. Reliance on “later Transport Canada approved revisions.” The AD permits performing the SB procedures in accordance with “or later Transport Canada approved revisions.” That creates a potential coordination need: an operator must confirm whether a later revision has been approved by Transport Canada, and whether CASA accepts that revision for the purposes of the AD. The AD permits usage of those revisions, but it is silent about later CASA approvals; operators must take care to confirm the revision’s approval status.

7. Documentation and record-keeping expectation. While not spelled out as a record-keeping clause, the AD’s sequencing and reliance on scheduled inspections implies a need to document the inspection results, any washer correction or bolt replacement, and the torque checks, to demonstrate compliance at audit. Failure to document properly could be an enforcement vulnerability.

8. Narrow locus of the unsafe condition. The AD identifies “some helicopters that have a CRES steel fitting installed at the upper left hand location of the tailboom” as potentially affected. That narrow locus means that two otherwise identical helicopters may have different obligations depending solely on whether that specific fitting was installed. Operators with diverse fleet configurations may need to inspect records carefully to identify which airframes are affected.

9. No direct alternative means of compliance or waiver in the AD text. The AD does not list an alternative means of compliance or waiver process within the instrument. Where an operator believes a different corrective action would be equally safe, the AD text does not itself open that path; the AD does, however, allow later Transport Canada approved SB revisions.

10. Effective date post-dates the initial compliance reference date. The AD becomes effective on 7 June 2007, but the initial inspection timing is referenced to 10 May 2007 (“within 50 hours time in service after 10 May 2007”). This can generate confusion when calculating compliance windows because the 10 May 2007 anchor date pre-dates the AD’s effective date.

These items are concrete procedural or documentary risks that follow from the AD’s language. Operators and maintainers should ensure accurate parts identification, obtain the referenced Alert Service Bulletins and maintenance manual, schedule inspections and torque checks according to the AD’s sequencing, and keep clear maintenance records that tie actions to the AD’s required milestones.

Compliance under this AD is a sequence of identification, inspection, correction/replacement if required, and torque verification. The AD specifies the controlling documents and explicit timing windows. Below are the steps an operator should follow, as mandated by the AD text.

1. Confirm applicability (Requirement step 1). Determine whether the helicopter is one of the listed models (206A, 206B, 206L, 206L-1, 206L-3, 206L-4) and whether the upper left hand tailboom attachment fitting is the CRES steel fitting, part number 407-030-750-103. The AD’s Applicability section lists the models and Requirement step 1 identifies the fitting by part number. Do not proceed to the following actions unless that fitting is indeed installed.

2. Obtain and consult the specified Alert Service Bulletin Part I. If the specified CRES fitting is installed, acquire Bell Helicopter Textron Canada Alert Service Bulletin 206-06-110 or 206L-06-140 (as applicable to the model) and, if appropriate, any later Transport Canada approved revisions (the AD permits use of those approved revisions). Part I contains the inspection procedure and the washer-correction instructions referenced in the AD. The AD text requires that inspection and any required washer correction be completed “in accordance with Part I... or later Transport Canada approved revisions.”

3. Perform the initial inspection and correct washer installation where required. Carry out the inspection of the upper left hand tailboom attachment bolt exactly as described in Part I of the relevant Alert Service Bulletin. If the inspection identifies improper washer installation, correct the washer installation in accordance with Part I’s procedures. Record the inspection and any corrective steps in the helicopter’s maintenance log, noting dates, hours time in service and the reference to the Alert Service Bulletin used.

4. Meet the initial time window. Complete the Part I inspection and any washer correction within 50 hours time in service after 10 May 2007 unless the inspection has already been accomplished. The AD’s Compliance section sets this as the initial requirement. Accurately calculate hours time in service from the 10 May 2007 anchor to confirm compliance within the 50-hour window.

5. If replacement is deemed necessary after the inspection, use Part II of the Alert Service Bulletin. Should the Part I inspection reveal that bolt replacement is necessary, perform the replacement “in accordance with Part II of Bell Helicopter Textron Canada Alert Service Bulletin 206-06-110 or 206L-06-140, as applicable; or later Transport Canada approved revisions,” as the AD instructs. Maintain records of the replacement action including part numbers, serial numbers where applicable, and reference to Part II procedures followed.

6. Schedule and perform torque checks per the maintenance manual. The AD requires performing a torque check of the upper left hand tailboom attaching hardware “in accordance with the applicable maintenance manual.” The Compliance section ties the timing: (a) perform a torque check at the next scheduled 100-hour inspection or annual inspection (whichever occurs first) after completing Part I; and (b) if bolt replacement occurred, perform a torque check at the next scheduled 100-hour inspection following the replacement. Ensure the torque values and procedures used are those in the applicable maintenance manual and document the torque check date, inspector and results.

7. Retain documentation for audit. Record each step , determination of part number, Part I inspection and findings, any washer corrections, any Part II replacement work, torque checks and maintenance manual references , in the helicopter’s maintenance records. The AD’s sequencing and timed obligations make clear that records will be the primary means to demonstrate compliance.

8. Use of later Transport Canada approved revisions. If a later Transport Canada approved revision of the relevant Alert Service Bulletin is available, the AD permits use of that revised SB for compliance. Confirm that the revision is indeed Transport Canada approved and document which revision was used when recording compliance actions.

9. Confirm the AD effective date and carry out actions accordingly. The AD “becomes effective on 7 June 2007,” but the initial compliance window is anchored to 10 May 2007. Ensure the initial inspection timing is calculated correctly relative to 10 May 2007, and that any subsequent torque checks are scheduled per the AD’s instructions.

10. Coordinate with maintenance providers and parts suppliers. If replacement parts are required pursuant to Part II, procure the correct replacement bolt specified in the Alert Service Bulletin and ensure installation is performed by appropriately qualified maintenance personnel in accordance with the SB and maintenance manual.

Following these steps, and keeping contemporaneous maintenance records that reference the AD, the applicable Alert Service Bulletins and the maintenance manual, implements the AD’s requirements as stated in the document. The AD does not itself provide alternative compliance methods or waivers in its text; operators wishing to rely on other procedures should verify whether such alternatives are acceptable to CASA or whether a Transport Canada approved SB revision can be used.