AD/BELL 222/37 - Tail Rotor Pitch Change Mechanism

The AD is structured around a small set of technical and regulatory concepts that determine what must be done, for which aircraft, and within what timeframe. These concepts appear in the AD headings and instructions and are the only source material to ground analysis.

• Applicability: The AD applies to specific serial number ranges of BHTC models 222 and 222B and to all serials of 222U. The text lists the exact serial ranges: Model 222 serial numbers 47006 through 47089; Model 222B serial numbers 47131 through 47156; Model 222U, all serial numbers. Applicability is the gate that determines which owners/operators are subject to the AD’s requirements.

• Accomplishment Instructions: The technical work is not described step‑by‑step in the AD itself; instead, the AD requires work “in accordance with the Accomplishment Instructions provided in the applicable Alert Service Bulletin (ASB) listed below, or later NAA approved revisions.” The ASBs identified are 222‑07‑104 (222/222B) and 222U‑07‑75 (222U), both issued 9 January 2007. The AD therefore delegates the detailed maintenance procedure to those ASB Accomplishment Instructions and to any later NAA‑approved revisions of those ASBs.

• Verification and corrective action: The AD distinguishes verification (inspect/verify the existing rigging) from corrective action (replace tail rotor yoke if Item 3 of the ASB requires it; perform new rigging procedure). The AD’s Requirement is framed as sequential items: verify, then check whether replacement is required, then perform the new rigging.

• “Airworthy part”: Where replacement is required, the AD mandates replacement “with airworthy part.” The AD does not define “airworthy” further; the term appears as a condition on acceptable replacement parts.

• Compliance timing: The AD ties compliance to routine maintenance scheduling: next 150‑hour or next annual inspection, with a hard outer deadline of 31 December 2007. The AD also carries an effective date (2 August 2007) and a signed date (21 June 2007).

• Cross‑reference to other regulatory instruments: The AD notes Transport Canada AD CF 2007‑07 dated 11 April 2007 “refers,” signalling regulatory coordination or shared technical concern with another jurisdiction.

These concepts determine what documentation is necessary (the ASBs and any later NAA approvals), who needs to act (owners/operators of the listed serials), the technical scope (tail rotor pitch change mechanism rigging and possible yoke replacement), and the timing constraints (next 150‑hour/annual inspection, no later than 31 December 2007). The AD does not itself include the technical rigging steps, nor does it set out inspection forms, certification entries, or penalties; it relies on the ASBs and on the AD framework to make the actions mandatory.

The AD’s Applicability section names the specific helicopters subject to its requirements. Owners and operators of Bell Helicopter Textron Canada (BHTC) Models 222 with serial numbers 47006 through 47089; Models 222B with serial numbers 47131 through 47156; and Model 222U of any serial number are within scope. That list is the sole source basis for determining which airframes the AD reaches.

Consequently, primary affected parties are:

• Aircraft owners: the legal owners of the affected airframes will be responsible for ensuring compliance with the AD. The AD’s text obliges verification and possible replacement and re‑rigging of components for the airframes listed.

• Operators and commercial operators: organisations that operate affected helicopters on a commercial or private basis must ensure the required work is completed within the compliance window (next 150‑hour or annual inspection, or by 31 December 2007).

• Maintenance organisations and maintenance personnel: the AD requires work “in accordance with the Accomplishment Instructions” in the ASBs or later NAA approved revisions. That pushes detailed technical execution to maintenance providers who must obtain and follow the ASB Accomplishment Instructions. The AD’s reference to “airworthy part” implies use of components that meet the applicable airworthiness standards, which will be determined through maintenance practice and NAA approval processes.

• Parts suppliers and component manufacturers: where the AD finds that a yoke replacement is required (per Item 3 of the ASB Accomplishment Instructions), suppliers must furnish “airworthy part[s]” compatible with the specified models and serial numbers. The AD’s text therefore affects the immediate demand for such parts for the listed serial ranges.

• Regulatory coordinators and NAAs: the AD explicitly allows reliance on later NAA approved revisions of the ASBs, and it references a Transport Canada AD (CF 2007‑07 dated 11 April 2007). This indicates that regulators outside Australia and their approved revisions of ASBs play a role in determining acceptable technical content.

Parties not listed in the Applicability section are not covered by this AD according to the source text. The AD does not create obligations for other models, nor does it single out particular operators by name. The AD does not itself specify who must pay for the work, issue certificates of release to service, or undertake compliance audits; those operational details are not set out in the AD text and will fall to the usual arrangements between owners, operators, and maintenance organisations within the applicable regulatory framework.

The AD sets out three sequential duties for affected helicopters, and provides conditional tolerances about acceptable technical authority.

Duties (as expressed in the AD Requirement text):

1. Verify existing rigging: Operators must “Verify the existing rigging of the tail rotor pitch change mechanism in accordance with the Accomplishment Instructions provided in the applicable Alert Service Bulletin (ASB) listed below, or later NAA approved revisions.” This duty requires obtaining and following the ASB Accomplishment Instructions (ASB 222‑07‑104 for 222/222B or ASB 222U‑07‑75 for 222U), unless and until a later NAA approved revision supersedes them.

2. Verify and, if necessary, replace the tail rotor yoke: The AD requires verification “if the tail rotor yoke replacement is required, as per Item 3 of Accomplishment Instructions of applicable ASB. If required; replace the yoke with airworthy part.” That duty is conditional on the ASB’s Item 3 findings; when Item 3 indicates replacement, replacement with an “airworthy part” is mandatory.

3. Perform new rigging: Operators must “Perform a new rigging procedure as per Accomplishment Instructions of the applicable ASB or later NAA approved revisions.” This is the substantive corrective action intended to address the parts‑interference risk identified in the Background section.

Timing duty: All the above duties must be completed “At the next 150 hour or annual inspection but no later than 31 December 2007, unless already accomplished.” The AD is effective 2 August 2007, so compliance must be scheduled within that window. The AD was signed 21 June 2007.

Rights and procedural features stated in the AD:

• Use of later NAA approved revisions: The AD authorises (permits) compliance using the listed ASBs “or later NAA approved revisions.” That gives operators and maintenance organisations the procedural right to use a superseding ASB that has been approved by the relevant National Airworthiness Authority (NAA) instead of the original ASB listed.

• Reliance on ASB Accomplishment Instructions: The AD delegates the technical method to the ASB Accomplishment Instructions; the AD itself does not mandate specific torque values, rigging dimensions, or steps. The right , or procedural option , is therefore to follow those externally maintained instructions.

Matters the AD does not state as duties or rights:

• The AD does not set out who must pay for parts or labour; it does not specify documentation or recordkeeping steps; it does not specify whether a particular licence class must perform the work (for example an approved maintenance organisation). Those operational responsibilities are left implicit or to be determined under the broader maintenance and regulatory framework, which the AD does not reproduce.

• The AD does not define “airworthy part” nor set out the process for demonstrating that a replacement part is airworthy; it simply mandates replacement with an airworthy part where ASB Item 3 requires replacement.

The net effect is a mandatory set of actions tied to existing maintenance events, with procedural flexibility to use later NAA‑approved revisions of the ASBs, and with technical execution delegated to the ASB Accomplishment Instructions.

The AD text itself does not specify civil or criminal penalties, nor does it include an enforcement section describing administrative sanctions. The document identifies the issuing authority (CASA) by signature , “David Punshon, Delegate of the Civil Aviation Safety Authority” dated 21 June 2007 , and it states that “This Airworthiness Directive becomes effective on 2 August 2007.” The Background text uses the word “mandates” , “This AD mandates verification of the tail rotor pitch change mechanism and new rigging procedures” , which establishes the directive nature of the instrument in regulatory terms.

Beyond that, the AD contains no express penalty clauses, infringement notices, or enforcement procedures. The AD refers to technical compliance obligations and to a compliance timeframe (“At the next 150 hour or annual inspection but no later than 31 December 2007”). The absence in the AD text of specific penalty provisions means that any enforcement mechanisms, sanctions, or administrative processes would originate from the broader legal framework that empowers CASA and governs aviation safety and airworthiness (that framework is not reproduced within this AD text). The AD itself does not enumerate how CASA will verify compliance, audit operators, or impose any sanction for non‑compliance.

The AD does, however, cross‑reference technical standards and other NAAs, for instance by listing the ASBs and by noting the Transport Canada AD CF 2007‑07 dated 11 April 2007. Enforcement practice in aviation typically flows from the issuing authority’s statutory powers and administrative processes; the AD document is the mandatory technical instruction that will be operationalised under those powers. The AD’s effective date and hard compliance deadline provide the temporal basis for any enforcement action an authority might take, but the AD text does not itself narrate those enforcement actions or penalties.

Therefore, from the AD text alone: actions are mandated, timing is specified, the issuing authority is named, but specific penalties and enforcement procedures are not set out in the AD itself.

The AD explicitly cross‑references a Transport Canada Airworthiness Directive. The AD’s Note states: “Transport Canada AD CF 2007‑07 dated 11 April 2007 refers.” This is the only cross‑jurisdictional or inter‑regulatory reference present in the AD text. The AD also permits compliance using “the Accomplishment Instructions provided in the applicable Alert Service Bulletin (ASB) listed below, or later NAA approved revisions.” That language links the AD to technical documents and to the approval processes of National Airworthiness Authorities (NAA). The AD therefore operates within a regulatory ecology where (a) the detailed technical means of compliance are defined by ASBs and (b) those ASBs may be updated or revised and those revisions must be approved by an NAA in order to be used for compliance.

The AD itself does not quote, amend, or repeal any statute or regulation. It is an administrative directive imposing mandatory technical requirements for specified aircraft. How it interfaces with general regulatory obligations (such as continuing airworthiness rules, maintenance release requirements, operating certificates, and recordkeeping obligations) is not spelled out in the AD text. Those interfaces are handled by the broader regulatory framework under which CASA issues ADs; this AD supplies the specific technical requirement that owners/operators must meet to keep an affected aircraft airworthy.

By referring to ASBs and NAA approvals, the AD recognises the role of the State of Design or other NAAs in providing technical guidance. The AD thereby permits technical harmonisation and the adoption of later NAAs’ approved revisions, which can reduce conflict between domestic AD requirements and international design authority guidance. The AD does not, however, state which NAA has primacy over ASB revisions, nor does it establish any mechanism for resolving conflicts between the ASBs and this AD.

Finally, the AD’s reference to “airworthy part” establishes a link to airworthiness standards and parts approval regimes, but the AD does not define the applicable airworthiness standard or the certification process for parts. Those matters will be governed by the usual legal and regulatory rules that deal with parts certification and airworthiness in the relevant jurisdiction, which are not reproduced in this AD.

In short, the AD interacts with other laws and instruments by cross‑referencing ASBs, NAA approvals and a Transport Canada AD, but it does not itself reproduce or resolve the broader statutory or regulatory provisions governing enforcement, certification of parts, or maintenance recordkeeping.

The AD text as supplied contains no recorded amendments, variations, or subsequent supersessions. The document indicates the following temporal milestones:

• ASB issue dates: the two Alert Service Bulletins specified in the AD are identified as issued on 9 January 2007 (ASB 222‑07‑104 for Models 222 and 222B, and ASB 222U‑07‑75 for Model 222U).

• Transport Canada cross‑reference: Transport Canada AD CF 2007‑07 dated 11 April 2007 is referenced in the AD Note, indicating a related instrument issued earlier in 2007.

• AD signature and dates: the AD was signed by David Punshon as Delegate of CASA on 21 June 2007, and the AD becomes effective on 2 August 2007.

• Compliance deadline: the AD sets a hard compliance outer date of 31 December 2007, with the operative requirement that actions be carried out at the next 150‑hour or annual inspection before that date, unless already accomplished.

The AD text also contains the instruction that compliance may be carried out “in accordance with the Accomplishment Instructions provided in the applicable Alert Service Bulletin (ASB) listed below, or later NAA approved revisions.” That language implicitly anticipates the possibility of later technical revisions to the ASBs; however, the AD itself does not record any such later revision, nor does it record an amendment to the AD. The AD does not include an amendment log, nor does it indicate whether CASA expects to issue a future amendment to the AD. There is no textual evidence in the AD of revocation or supersession of prior CASA ADs.

Therefore, based solely on the AD text, the amendment history is limited to the AD’s own issuance dates, the ASB issue dates, and the cross‑reference to the Transport Canada AD. No further amendments or historical changes are documented in the supplied material.

The AD text does not disclose any litigation history. It makes no reference to judicial review, appeals, disputes, or precedent. The document is an administrative directive containing technical instructions, applicability, compliance timing, and a background safety rationale. It does not include any report of litigation, nor does it reference any case names or decisions.

Because the AD is a technical compliance instrument and the supplied text contains neither legal argumentation nor references to past litigation, there is no litigation record to summarise within this source. Any proceedings, challenges, or disputes that may have arisen from this AD would need to be sourced from other documents or legal records; they are not present in the AD as supplied.

In short, based on the supplied AD document, there is no litigation history to report.

The AD text contains several points that create potential practical traps for owners, operators and maintenance organisations. These matters are drawn strictly from the AD wording.

• Applicability is narrow and serial‑specific: The AD applies to precise serial number ranges for Models 222 and 222B and to all serials of 222U. Owners or operators who do not check the serial number correctly risk assuming liability or compliance status incorrectly. The Applicability heading is the sole determinant of who must comply: Model 222 serial numbers 47006 through 47089; Model 222B serial numbers 47131 through 47156; Model 222U, all serial numbers. If an operator misreads serials, they may fail to act while being covered, or conversely spend resources unnecessarily.

• Reliance on ASBs and NAA approved revisions: The AD requires work “in accordance with the Accomplishment Instructions provided in the applicable Alert Service Bulletin (ASB) listed below, or later NAA approved revisions.” The AD therefore does not itself include technical rigging instructions; compliance depends on obtaining the correct ASB (ASB 222‑07‑104 or ASB 222U‑07‑75) and on ensuring that any used revision is NAA‑approved. If a maintenance provider follows an ASB revision that is not NAA‑approved, the work may not satisfy the AD, even if technically correct.

• Conditional replacement requirement: The AD instructs operators to “Verify if the tail rotor yoke replacement is required, as per Item 3 of Accomplishment Instructions of applicable ASB. If required; replace the yoke with airworthy part.” That makes replacement conditional, not automatic. Misinterpretation of Item 3 in the ASB could lead to unnecessary replacements or to failing to replace a yoke that the ASB requires to be replaced.

• “Airworthy part” is unspecified: The AD mandates replacement with an “airworthy part” but does not define how airworthiness is to be demonstrated or who certifies the replacement part as airworthy. This gap leaves operators to rely on their normal parts approval processes and on NAAs or ASB guidance for determining acceptable parts. Using an uncertified or non‑airworthy part could fail to meet the AD’s requirement.

• Tight compliance window tied to inspection schedule: The AD requires compliance at the “next 150 hour or annual inspection but no later than 31 December 2007.” Operators with infrequent inspection cycles may find that the “next” inspection falls after the hard deadline; conversely, those who have recently had an inspection may need to schedule additional maintenance before the deadline to comply. Misreading the timing requirement could create late compliance.

• Cross‑jurisdictional references: The AD refers to Transport Canada AD CF 2007‑07. If an operator or maintenance provider attempts to rely on Transport Canada guidance instead of the ASBs listed, they must ensure the Transport Canada AD’s instructions align and that any alternative documents are appropriately approved by the NAA referenced by CASA. Failure to align cross‑jurisdictional documents could lead to non‑conformance with this AD.

• AD versus ASB differences: Because the AD delegates the technical steps to external ASBs, any discrepancy between the AD’s intent (parts interference risk) and the technical steps in an ASB or its later revision could create uncertainty. The AD does not include an explicit instruction for resolving conflicts between the AD text and ASB text; the AD simply requires compliance with the ASB Accomplishment Instructions or later NAA approved revisions.

These are concrete operational “gotchas” emerging from the AD’s language and structure. They concern identification of affected assets, correct sourcing of the ASB and its approved revisions, correct application of conditional replacement requirements, demonstration of a part’s airworthiness, and timely scheduling of maintenance within the stated compliance window.

The AD confines compliance steps to three actions executed in accordance with the Accomplishment Instructions of the identified ASBs (or later NAA approved revisions), together with the stated timing constraint. Below are the practical steps that flow directly from the AD wording.

1. Confirm applicability: Check the helicopter make/model and serial number against the AD’s Applicability table. The AD applies to:

   • Bell Helicopter Textron Canada (BHTC) Model 222, serial numbers 47006 through 47089;
   • BHTC Model 222B, serial numbers 47131 through 47156;
   • BHTC Model 222U, all serial numbers. If an airframe is not within these serial ranges or models, the AD’s requirements, as written, do not apply.

2. Obtain the applicable ASB or later NAA approved revision: For Model 222 and 222B, obtain ASB 222‑07‑104 issued 9 January 2007; for Model 222U, obtain ASB 222U‑07‑75 issued 9 January 2007. The AD permits using “later NAA approved revisions,” so confirm with the relevant NAA whether there is a later approved revision of the ASB and, if so, obtain and use that revision.

3. Verify existing rigging: Using the Accomplishment Instructions in the applicable ASB (or later NAA approved revision), verify the existing rigging of the tail rotor pitch change mechanism. Follow the ASB’s step‑by‑step procedure as written; the AD itself does not detail those steps.

4. Check Item 3 (yoke replacement): The AD requires a specific check of ASB Item 3 to determine whether the tail rotor yoke must be replaced. If Item 3 indicates replacement is required, replace the yoke with an “airworthy part.” Ensure that the replacement part meets the applicable airworthiness standards and is acceptable under the relevant parts approval regime. The AD requires replacement “with airworthy part” but does not specify how airworthiness is to be demonstrated; rely on the applicable NAA rules and parts certification processes.

5. Perform new rigging procedure: Complete the new rigging procedure as specified in the ASB Accomplishment Instructions (or later NAA approved revision). The AD mandates that the new rigging be performed, which is intended to eliminate possible parts interference identified in the AD Background.

6. Timing: Schedule and carry out the verification, replacement (if required), and re‑rigging “at the next 150 hour or annual inspection but no later than 31 December 2007, unless already accomplished.” If the aircraft’s next scheduled inspection is after 31 December 2007, ensure work is brought forward so the AD’s hard deadline is met.

7. Use approved revisions only: If choosing to rely on a later ASB revision, confirm that it is NAA approved , the AD allows “later NAA approved revisions” only. Work carried out to an unapproved revision may not satisfy the AD.

8. Maintain operational coordination: Although the AD does not prescribe documentation or release procedures, execute the maintenance in accordance with the applicable maintenance release and airworthiness procedures in force under the operator’s regulatory regime. Because the AD requires replacement with airworthy parts when necessary, ensure parts sourcing and certification are handled under your standard parts approval system.

9. Cross‑reference Transport Canada AD: The AD notes that “Transport Canada AD CF 2007‑07 dated 11 April 2007 refers.” Where appropriate, review that Transport Canada AD to confirm alignment between the technical instructions and to identify any supplementary guidance.

The AD does not specify paperwork or logging requirements inside the AD text; operators should therefore follow their normal regulatory obligations for recording maintenance and returning aircraft to service, in addition to performing the AD tasks. The AD requires execution of tasks at established maintenance events and does not itself provide exemption or deferment mechanisms within its text; compliance must therefore be planned and executed as a discrete maintenance action at or before the stated deadline.