AD/BELL 206/179 - Main Rotor Pitch Horn Bearing

The AD rests on several discrete, interlocking concepts laid out in the text.

• Applicability and fleet definition. The AD defines the affected fleet precisely in Table 1 by helicopter model and serial number ranges. Some models are listed as “All serial numbers” (206A), others by explicit serial ranges (206L variants). The AD also notes converted airframes, for example 206B “including those converted from Model 206A” up to serial 4660. That means compliance is tied to serial-numbered airframes rather than production year or registration, and converted airframes are expressly captured.

• Component-specific action. The AD targets a single part, bearing P/N 206-011-105-001, described throughout as “Main Rotor Pitch Horn Bearing”. The inspection and replacement obligations apply solely to that part (Requirement 1 and 2).

• Prescriptive inspection method via external service bulletins. The AD does not set a standalone inspection procedure. Instead it mandates inspection “in accordance with Accomplishment Instructions provided in the applicable Alert Service Bulletin listed in Table 2 of this AD dated 25 February 2009, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada” (Requirement 1). The AD therefore imports by reference the technical content and procedural steps contained in ASBs 206-09-120 and 206L-09-154.

• Conditional replacement standard. The AD requires replacement “if, as a result of the inspection detailed in Requirement 1 of this AD, the bearing needs to be replaced” and sets a timing obligation that replacement must be “before further flight” (Requirement 2). The AD does not define “needs to be replaced” itself; that determination is to be made by applying the criteria in the referenced ASB.

• Compliance timing. The AD sets a short compliance window: the inspection must be completed “within 30 days after the effective date of this AD, unless previously accomplished.” The effective date is stated as 22 October 2009, so the inspection window runs from that date (Compliance section).

• Safety premise. The Background provides the causal safety rationale: certain bearings were manufactured without the required lubrication passage, which could lead to loss of control of the helicopter if uncorrected. That statement sets the risk context the AD is responding to.

• Cross-jurisdictional technical authorisation. The AD accepts later revisions of the referenced Alert Service Bulletins only if those revisions are “approved by the Chief, Continuing Airworthiness, Transport Canada.” It also notes Transport Canada AD CF-2009-34 dated 25 August 2009, thereby tying Australian regulatory action to a Transport Canada response.

These concepts structure the operator’s obligations: identify applicability by serial number, obtain the relevant ASB, perform the inspection within 30 days, and replace any bearing found defective before further flight. The AD does not itself contain the inspection thresholds or detailed steps; those are in the ASBs the AD cites.

The AD affects identifiable groups and resources.

• Registered operators and owners of the listed Bell 206 and Agusta Bell 206 series helicopters. The AD defines the affected helicopters by model and serial number in Table 1. Examples include all serial numbers of model 206A, 206B up to 4660 (including those converted from 206A), and defined serial ranges for 206L series models (for instance 206L serials 45004 through 45153 and 46601 through 46617, 206L-1 serials 45154 through 45790, 206L-3 serials 51001 through 51612, 206L-4 serials 52001 through 52388). Any person or company operating those specific airframes must comply.

• Maintenance organisations and maintenance personnel. The AD requires inspection “in accordance with Accomplishment Instructions” in the relevant Alert Service Bulletin. That means maintenance technicians, licensed mechanics or maintenance organisations that perform these inspections must follow those technical instructions and apply any pass/fail criteria contained in the ASB. The AD implicitly requires that responsible maintenance personnel can access and apply the ASB dated 25 February 2009 or an approved later revision.

• Parts suppliers and inventories. The AD identifies the specific part number 206-011-105-001. Where an inspection shows replacement is necessary, the operator must source a “serviceable bearing”. That means parts suppliers, distributors or overhaul facilities holding inventory for the bearing may be engaged to supply replacements. If serviceable bearings are scarce, operators face supply risk and potential grounding.

• Regulatory authorities. The Civil Aviation Safety Authority (CASA) is the issuer: the AD is signed by James Coyne as a Delegate of CASA (signed 10 September 2009). The AD also references Transport Canada for approval of later ASB revisions and cross-references Transport Canada AD CF-2009-34 dated 25 August 2009. Thus both CASA and Transport Canada feature as decision-makers for approval of ASB revisions and as points of reference for regulatory synchrony.

• Flight operations and scheduling stakeholders. Because Requirement 2 mandates replacement “before further flight” when replacement is indicated, flights using affected airframes that fail inspection must be postponed until the part is replaced. That affects operators’ customers, charter clients, insurers, and any contractual obligations dependent on aircraft availability.

• Airworthiness records and compliance auditors. Operators must document completion of the inspection within the 30-day window and any replacement actions taken. Those records will be relevant for airworthiness audits and for regulatory oversight.

The AD’s applicability language and serial-number detail create a clear, but narrow, population. Any person involved with the operation, maintenance, parts procurement or regulatory oversight of those serial-numbered airframes must engage with the AD’s requirements.

The AD creates two primary statutory duties and several ancillary procedural expectations.

Primary duties

• Inspect the bearing P/N 206-011-105-001. Requirement 1 states: “Inspect the bearing, P/N 206-011-105-001, in accordance with Accomplishment Instructions provided in the applicable Alert Service Bulletin listed in Table 2 of this AD dated 25 February 2009, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.” This creates a duty to obtain and follow the ASB instructions (ASB 206-09-120 for 206A/206B; ASB 206L-09-154 for 206L variants) and to complete that inspection within the compliance window.

• Replace defective bearings before further flight. Requirement 2 states: “If, as a result of the inspection detailed in Requirement 1 of this AD, the bearing needs to be replaced, replace it with a serviceable bearing.” The timing obligation “before further flight” converts any negative finding into an immediate grounding requirement for that airframe until a serviceable bearing is installed.

Timing duties

• The AD sets a firm inspection deadline: “For Requirement 1 - Within 30 days after the effective date of this AD, unless previously accomplished.” The effective date is 22 October 2009, so the inspection must be completed within 30 days of that date unless an operator had already completed the inspection earlier.

Procedural constraints and dependencies

• Use of the Alert Service Bulletins. The inspection must be performed “in accordance with Accomplishment Instructions provided in the applicable Alert Service Bulletin listed in Table 2 of this AD dated 25 February 2009, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.” The AD thereby requires adherence to the ASB’s test criteria, inspection methods and acceptance/rejection thresholds. If an operator wishes to use a later ASB revision, that revision must be approved by the named Transport Canada official.

• Parts conformity. Replacement bearings must be “serviceable”. The AD does not define “serviceable” beyond common aviation maintenance usage. The practical implication is that replacement parts must meet airworthiness standards and be acceptable under maintenance regulations.

Rights and decision nodes

• Right to use later ASB revisions only with approval. Operators do not have an automatic right to adopt subsequent ASB revisions; adoption requires approval by the Chief, Continuing Airworthiness, Transport Canada. The AD therefore delegates a gatekeeping function to that foreign authority for any ASB updates.

• Rights not stated in the AD. The AD text does not articulate appeals processes, exemptions, or alternative means of compliance. It also does not carry any explicit waiver or penalty provisions in the text supplied. Those matters, if available, must be sought in other regulatory texts or by contacting CASA or Transport Canada.

Recordkeeping and proof of compliance

• The AD’s requirements imply an obligation to demonstrate compliance by maintaining inspection records and any replacement documentation. The AD itself does not set recordkeeping formats, but the obligation to act within the timeframes and the before-flight replacement requirement practically requires documentation to support airworthiness.

In sum, the AD imposes a short-term inspection duty and a conditional replacement duty anchored to specific ASB procedures. It centralises technical authority for any ASB revisions with the Chief, Continuing Airworthiness, Transport Canada, and leaves implementation details such as parts sourcing and the definition of “serviceable” to maintenance practice and applicable airworthiness rules outside the text.

The AD text supplied does not set out explicit penalties, enforcement mechanisms, or administrative sanctions. The document contains the prescriptive obligations (inspect within 30 days, replace before further flight where indicated), the effective date (22 October 2009), and the signature line (James Coyne, Delegate of the Civil Aviation Safety Authority, dated 10 September 2009), but it does not include any clauses that specify penalties, fines, or criminal offences for non-compliance.

Because the AD does not itself specify enforcement procedures, the AD leaves open two points:

• The AD does not state enforcement mechanisms in its text. There is no section within the provided document that prescribes which enforcement action CASA or another body will take in response to non-compliance, nor does the AD set out monetary penalties or administrative sanction processes.

• The AD does create binding operational constraints. Requirement 2’s timing , replacement “before further flight” if replacement is indicated , effectively imposes an immediate operational restriction: an aircraft that fails the inspection cannot be legally flown until the replacement is made, according to the AD’s terms. The AD therefore implies an operational enforcement effect by tying continued flight to completion of the specified maintenance action.

Practical enforcement and compliance monitoring implications that follow from the AD’s text

• Grounding effect. The “before further flight” language creates a functional grounding obligation for any aircraft whose bearing is found to require replacement. That is a direct operational consequence embedded in the AD’s timing obligation.

• Record evidence. Because compliance is time-limited and flight-critical, operators will need documentary evidence that the inspection and any required replacement were completed. While the AD does not prescribe the record format, maintaining such records will be necessary to demonstrate compliance to any regulator or auditor.

• Cross-reference to Transport Canada. The AD’s reliance on Transport Canada for approval of later ASB revisions and its reference to Transport Canada AD CF-2009-34 suggest that enforcement and technical coordination could involve cross-jurisdictional consultation, although the AD text does not elaborate on any cooperative enforcement procedures.

Because the AD itself is silent on fines, penalties or formal enforcement steps, parties requiring those specifics must consult the wider regulatory framework under which ADs are issued and enforced. The text provided does not include that wider framework, and therefore does not authorise drawing conclusions about statutory penalties beyond what the AD explicitly states.

The AD expressly interacts with and incorporates materials from another jurisdictional regulator and from manufacturer-issued service bulletins. The document ties its technical procedures and approval pathway to Transport Canada and to model-specific Alert Service Bulletins.

• Incorporation by reference of Alert Service Bulletins. The AD mandates inspection “in accordance with Accomplishment Instructions provided in the applicable Alert Service Bulletin listed in Table 2 of this AD dated 25 February 2009, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.” Table 2 specifies ASB 206-09-120 for 206A and 206B and ASB 206L-09-154 for 206L series models. By doing so, the AD imports the ASBs’ technical inspection criteria, acceptance limits and procedural steps into its compliance obligations. The ASBs therefore function as incorporated technical standards.

• Cross-reference to Transport Canada AD. The AD includes a Note: “Transport Canada AD CF-2009-34 dated 25 August 2009 refers.” That establishes a link between CASA’s AD and Transport Canada’s airworthiness action on the same issue, making the AD part of a regulatory response that aligns with or follows a Transport Canada AD.

• Approval gateway located with foreign authority. The AD permits the use of later revisions of the listed ASBs only when approved by the Chief, Continuing Airworthiness, Transport Canada. This creates an interaction in which Australian compliance obligations reference and rely on a named official in another jurisdiction to approve subsequent technical updates. The AD therefore imports an external gatekeeper for future ASB revisions.

• No internal statutory cross-references provided. The AD as supplied does not quote or cite domestic legislation, enforcement provisions, exemptions, or administrative processes. It does not specify how it is enforced in Australian law or which domestic statutory provisions it depends on. The AD thus functions as a self-contained operational directive referencing technical materials and a foreign authority without embedding itself in the domestic statutory text within this document.

• Practical consequence for international operators and supply chains. Because the AD accepts Transport Canada’s technical material and approvals, operators who maintain fleets in multiple countries or source parts internationally will experience a regulatory alignment with Transport Canada procedures. The AD thereby creates an operational path that relies on manufacturer service bulletins and a foreign regulator’s approval of ASB revisions for future procedural changes.

• Recordkeeping and maintenance obligations implicit in aviation law. Although the AD does not itself state how records must be kept or how compliance will be demonstrated, by mandating inspections and before-flight replacement the AD interacts in practice with airworthiness recordkeeping obligations and maintenance regulations that govern how inspections and part replacements are documented and certified. Those interactions are implied by the AD’s operational requirements but are not specified in the supplied text.

In short, the AD binds compliance to manufacturer ASBs and to Transport Canada’s approval function while omitting explicit references to domestic statutory enforcement in the text supplied. It thus interacts with external technical and regulatory instruments while leaving domestic procedural and enforcement matters to the broader regulatory regime.

The AD text supplied contains a narrow amendment record in its own terms.

• Effective date and signature. The AD becomes effective on 22 October 2009. The document is dated and signed on 10 September 2009 by James Coyne, Delegate of the Civil Aviation Safety Authority. Those two dates mark the initial issuance timeline.

• Referenced external documents with dates. The AD mandates compliance with Alert Service Bulletins dated 25 February 2009 and refers to Transport Canada AD CF-2009-34 dated 25 August 2009. The AD also allows the use of “later revisions” of the referenced ASBs, but only if those later revisions are approved by the Chief, Continuing Airworthiness, Transport Canada. That creates a defined pathway for later technical amendments to be adopted into compliance obligations, subject to external approval.

• No subsequent domestic amendments listed. The supplied text does not contain any recorded subsequent amendments, revocations, supersessions, or variants of this AD beyond the effective date and references to the Transport Canada AD. There is no in-text schedule of amendments or version history beyond the dates already noted.

• Approval mechanism for ASB revisions as an amendment channel. The AD’s provision that later ASB revisions may be used only if approved by the named Transport Canada official is the only built-in mechanism within the AD for updating the operative technical instructions without issuing a new AD. That means technical amendments can be incorporated administratively via an approved ASB revision rather than by a CASA re-issue, subject to the external approval condition.

• No domestic amendment authority specified in the AD text. The document does not specify how CASA might amend the AD or how operators might request an alternative means of compliance within the Australian regulatory framework. The AD therefore leaves the procedural route for domestic amendment or exemption unaddressed in the text supplied.

For anyone tracking the regulatory status of this AD, the explicit timestamps are: ASBs dated 25 February 2009, Transport Canada AD CF-2009-34 dated 25 August 2009, CASA signature dated 10 September 2009, and CASA effective date 22 October 2009. Any information about later CASA amendments or supersessions will need to be sourced from CASA records outside of this AD text, because the AD itself contains no follow-up amendment history.

The AD as provided contains no litigation history or references to judicial proceedings. The document does not cite any cases, tribunal decisions, appeals, or litigated disputes concerning this AD. It also does not record any challenged enforcement actions, injunctions, or rulings.

Given the absence of litigation material in the text, there is nothing in this document to indicate whether the AD was contested in court, whether any judicial review was sought against CASA’s action, or whether any operator sought relief concerning the AD’s requirements. The AD’s only legal procedural markers in the supplied text are its issuance date, effective date, the serial-numbered applicability list, and the cross-reference to Transport Canada AD CF-2009-34.

If legal professionals require information on any subsequent litigation or administrative appeals, they must consult court records, tribunal dockets, or CASA’s enforcement and legal records. The AD document itself provides no litigation data, no case citations and no indication of judicial engagement.

This section flags concrete operational, compliance and interpretive pitfalls that follow from the AD’s text and structure.

• Serial-number specificity. The AD’s applicability is tied to model and serial-number lists in Table 1. Operators must identify the airframe’s serial number precisely. For 206B the AD covers “All up to 4660, including those converted from Model 206A.” That conversion language means that an airframe originally built as a 206A but converted to 206B may still be captured if its serial falls within the range. Failure to check conversion history or to verify serial numbers may lead to inadvertent non-compliance.

• Inspection method not contained in the AD. The AD does not include the inspection procedure or acceptance criteria. It requires reference to the applicable Alert Service Bulletin (ASB 206-09-120 or 206L-09-154) dated 25 February 2009. Operators must obtain the correct ASB and ensure they use the specified “Accomplishment Instructions.” Using an incorrect or unofficial procedure risks non-compliance.

• Later ASB revisions require external approval. The AD allows later ASB revisions only if approved by “the Chief, Continuing Airworthiness, Transport Canada.” That creates a potential administrative delay or confusion for operators operating in Australia who may assume CASA approval suffices. Operators must ensure that any ASB revision they rely upon has the specific Transport Canada approval referenced in the AD.

• Compliance window. The AD requires inspection “within 30 days after the effective date of this AD, unless previously accomplished.” The effective date is 22 October 2009. Operators that miscalculate the 30-day window or assume that the signed date (10 September 2009) is the compliance start date risk missing the mandated window. Clarify the effective date and compute the 30-day deadline accordingly.

• Before further flight replacement obligation. Requirement 2 requires any bearing that “needs to be replaced” to be replaced “before further flight.” If an inspection reveals a bearing requiring replacement and a serviceable replacement is not immediately available, the aircraft is effectively grounded until a serviceable part is installed. That creates operational risk, potential contractual exposure and scheduling impacts.

• Definition of “serviceable” not specified. The AD requires replacement with a “serviceable bearing” but does not define “serviceable.” Operators must rely on standard airworthiness and maintenance rules to determine what constitutes a serviceable part, including traceability, conformity, and any necessary inspection/certification of replacement parts.

• Interaction with foreign approvals and documentation. The AD depends on a Transport Canada approval gateway. Operators and maintenance organisations must ensure that the ASB revision they rely on is specifically approved by the named Transport Canada official and may need to obtain documentation of that approval to demonstrate compliance.

• Parts traceability and manufacturing defect specifics. The Background identifies a manufacturing defect: bearings “were manufactured without the required lubrication passage.” Operators should pay attention to part traceability and batch/lot information when sourcing replacements or when evaluating used parts. The AD does not provide remedial criteria other than replacement if inspection shows replacement is necessary.

• No penalties or enforcement language in the AD. The absence of explicit penalty provisions in the AD means operators cannot point to the AD text to determine consequences. Compliance obligations nevertheless exist in practical terms, but any legal consequences for non-compliance must be determined from the broader regulatory framework, not from this AD text alone.

• Recordkeeping and proof burden implicit. The AD’s time-limited and flight-critical obligations mean that operators will need contemporaneous records. The AD does not specify formats, so operators must ensure records satisfy whatever auditing standards CASA or applicable maintenance rules require.

These are operationally material pitfalls directly implied by the AD’s text. They focus on ambiguity about procedural sources, the need for serial-number diligence, dependency on a foreign approval gatekeeper, and immediate operational impacts where replacement is indicated.

The AD prescribes a clear, model-specific compliance pathway. The following steps derive from the AD’s text and the tables it contains.

1. Determine applicability by model and serial number. Consult Table 1 in the AD to confirm whether the aircraft is within the listed population. Examples from Table 1 include 206A “All serial numbers”; 206B “All up to 4660, including those converted from Model 206A”; 206L ranges such as 45004 through 45153 and 46601 through 46617; 206L-1 45154 through 45790; 206L-3 51001 through 51612; and 206L-4 52001 through 52388. Ensure conversions are checked against the explicit conversion note for 206B.

2. Identify the applicable Alert Service Bulletin. Use Table 2 to select the correct ASB: ASB 206-09-120 applies to 206A and 206B; ASB 206L-09-154 applies to 206L, L-1, L-3 and L-4 models. The AD requires inspection “in accordance with Accomplishment Instructions provided in the applicable Alert Service Bulletin listed in Table 2 of this AD dated 25 February 2009, or later revisions approved by the Chief, Continuing Airworthiness, Transport Canada.” Obtain the specific ASB dated 25 February 2009 unless a later revision has the required Transport Canada approval.

3. Schedule and perform the inspection within the required window. The AD states the inspection required by Requirement 1 must be performed “within 30 days after the effective date of this AD, unless previously accomplished.” The effective date is 22 October 2009. Plan maintenance resources and downtime to conduct the inspection within that 30-day window. Ensure qualified personnel perform the inspection and follow the ASB’s Accomplishment Instructions exactly, including any special tooling or test conditions the ASB requires.

4. Evaluate inspection results against ASB criteria. The AD delegates the determination of whether the bearing “needs to be replaced” to the outcome of the ASB inspection. Follow the ASB’s acceptance/rejection criteria to decide whether replacement is necessary. Document findings in the maintenance records.

5. Replace defective bearings before further flight. If the inspection shows the bearing needs replacement, the AD mandates replacement “with a serviceable bearing” before further flight. That requires sourcing a conforming replacement part P/N 206-011-105-001 or an acceptable alternative where permitted by maintenance rules. Confirm the replacement part’s traceability and serviceability under applicable maintenance standards.

6. Document compliance. Although the AD does not prescribe a recordkeeping format, maintain records demonstrating: the aircraft’s serial number and model; the date the inspection was performed; the ASB version used (and any evidence of Transport Canada approval if using a later revision); the inspection findings; part numbers of any replaced bearings; and certification or signatures required by maintenance regulations. These records will be needed to demonstrate compliance in audits and inspections.

7. If relying on a later ASB revision, obtain the required approval. The AD allows later ASB revisions only if approved by the Chief, Continuing Airworthiness, Transport Canada. If an operator seeks to use a later ASB revision than the ASB dated 25 February 2009, confirm and obtain documentary evidence that the later revision has the specified Transport Canada approval before relying on it for compliance.

8. Manage operational impacts. If the inspection indicates replacement is needed and no serviceable replacement is immediately available, prepare for the aircraft to be out of service until a replacement bearing can be procured and installed. Communicate with customers, insurers and scheduling partners about potential downtime and ensure contractual obligations are managed.

9. Coordinate with parts suppliers and maintenance organisations. Given the specific P/N and the manufacturing defect described in the Background, verify parts provenance and consider sourcing bearings with confirmed lubrication passages. Ensure maintenance organisations have the ASB and any required tooling or instructions.

10. Cross-reference Transport Canada AD and relevant manufacturer communications. The AD notes Transport Canada AD CF-2009-34 dated 25 August 2009 refers. Consult that AD and any manufacturer service letters for supplementary information, but ensure that any procedural changes are consistent with the CASA AD’s requirement to use ASBs approved by the Chief, Continuing Airworthiness, Transport Canada where later revisions are involved.

By following these steps, operators can align physical maintenance actions with the AD’s prescriptive obligations: inspect the specified bearing in accordance with the model-specific ASB within the 30-day window, and replace any defective bearing before further flight, documenting all steps taken.