AD/B717/4 Amdt 3 - Rudder Trim Control

The AD relies on four core concepts as set out in its own headings and wording: applicability by reference, mandatory compliance with an external manufacturer document, an AMOC pathway via FAA approval, and a terminating action that replaces repetitive maintenance.

• Applicability by reference. The AD applies to "Model 717 series aircraft, as listed in Boeing Alert Service Bulletin (ASB) 717-27A0016 Revision 2, or later FAA approved revision" (Applicability). That means the AD does not list tail numbers or serial ranges itself; it incorporates Boeing’s ASB as the definitive list of affected aeroplanes.

• Mandatory compliance with external service document. The actual technical requirement is "Action in accordance with the requirements of Boeing ASB 717-27A0016 Revision 2 or later revision approved by the FAA as an alternative method of compliance (AMOC)" (Requirement). The AD therefore mandates that operators follow the specified paragraphs and compliance times contained in that Boeing ASB, specifically Paragraph 1.E for compliance scheduling (Compliance).

• AMOC and FAA approval. The AD explicitly permits the use of later revisions of the listed service documents "approved by the FAA as an alternative method of compliance (AMOC)" (Applicability, Requirement). It also notes FAA AD 2001-18-11 Amdt 39-12437 for cross-reference (Requirement, Note). The FAA’s approval role is therefore embedded: subsequent revisions can only be used if the FAA has approved them as an AMOC.

• Terminating action via SB 717-27-0022 Rev 1. The AD makes compliance with Boeing SB 717-27-0022 Revision 1, or later FAA-approved revisions, "terminating action for the repetitive lubrication requirement of ASB 717-27A0016 Revision 2" (Requirement). Amendment 3 introduces that SB explicitly as an AMOC and as terminating action for the repetitive lubrication requirement (Amendment 3).

The Background frames the hazard: manufacturing with insufficient clearance between the actuator support seal and spring capsule assembly may allow moisture to condense and freeze in that area, producing stiff operation, binding, or jamming of the rudder trim control system and potentially jamming the rudder (Background). The corrective pathway set by the AD is therefore preventive maintenance initially (lubrication, with an initial and repeat requirement introduced by Amendment 1) and ultimate modification or repair that removes the need for repeated lubrication once SB 717-27-0022 Revision 1 has been accomplished and accepted by the FAA as an AMOC (Requirement; Amendment 1; Amendment 3).

Operationally, the AD is structured to make Boeing’s technical documents the operative law for maintenance action and to channel any departures from those documents through FAA-approved AMOCs. The AD identifies the relevant compliance paragraph in the ASB (Paragraph 1.E) as the locus for the required timelines and repeats (Compliance). The AD is effective as of a stated date and is signed by a CASA delegate, indicating a domestic regulatory instrument that cross-references international (FAA) approvals for technical acceptance.

The AD identifies affected parties primarily by reference to the Boeing ASB. It applies to operators, owners and maintenance organisations responsible for "Model 717 series aircraft, as listed in Boeing Alert Service Bulletin (ASB)717-27A0016 Revision 2, or later FAA approved revision" (Applicability). That means the immediate group who must take action are organisations that operate or maintain Model 717 series aeroplanes that appear on the list in that ASB revision.

Who pays. The text places the onus of performing the required actions on those responsible for the applicable aeroplanes. The Requirement clause directs action "in accordance with the requirements of Boeing ASB 717-27A0016 Revision 2", and the Compliance clause identifies the specific ASB paragraph that contains the compliance schedule. Performing lubrication tasks, record-keeping and ultimately accomplishing the terminating SB will be actions for which operators and their maintenance providers bear cost. The AD itself does not allocate funding, subsidies, exemptions, or cost-sharing mechanisms; it simply prescribes the technical and temporal obligations (Requirement; Compliance).

Who decides. The AD’s authorising signature is a CASA delegate, Mike Higgins, dated 1 April 2010, with the amendment effective 9 April 2010. The AD also embeds an approval role for the FAA: later revisions of the ASB or SB become acceptable only if approved by the FAA as an AMOC. Therefore compliance decisions, especially where an operator wishes to rely on a later revision, require FAA approval for the chosen document to qualify as an AMOC (Applicability; Requirement; Compliance).

Maintenance organisations and engineers are also affected in practice because the AD requires specific maintenance tasks and schedules as set out in Boeing’s ASB Paragraph 1.E. Amendment 1 introduced an "initial and repeat requirement to lubricate the actuator assembly" (Background). These are routine maintenance activities but create recurring workload and scheduling obligations. When SB 717-27-0022 Revision 1 is accomplished and accepted as terminating action, the maintenance burden created by the periodic lubrication requirements ceases for aircraft modified per that SB; until then, operators must continue repetitive lubrication as specified (Requirement; Amendment 3).

Other stakeholders implied by the AD include Boeing, as the author of the ASB and SB relied upon by the AD; and the FAA, whose approval is necessary for later revisions to be accepted as AMOCs. The AD also references the earlier FAA AD 2001-18-11 Amdt 39-12437, which indicates a connection with earlier regulatory action (Requirement, Note). The AD does not list enforcement agencies, penalties, or sanctioning mechanisms in the supplied text, and it does not identify specific serial numbers or operator identities itself, relying instead on the ASB for the lists of affected aircraft (Applicability; Compliance).

Key duties. The AD imposes the following concrete duties as stated:

• Duty to determine applicability. Operators must check whether their aircraft are "listed in Boeing Alert Service Bulletin (ASB)717-27A0016 Revision 2, or later FAA approved revision" to know whether the AD applies (Applicability).

• Duty to carry out the ASB tasks. The AD requires "Action in accordance with the requirements of Boeing ASB 717-27A0016 Revision 2 or later revision approved by the FAA as an alternative method of compliance (AMOC)" (Requirement). The technical tasks, intervals and any initial or repeat actions are those in the ASB, specifically Paragraph 1.E for compliance times (Compliance).

• Duty to perform repetitive lubrication until terminating action completed. Amendment 1 introduced an initial and repeat lubrication requirement for the actuator assembly, and Amendment 3 clarifies that accomplishing SB 717-27-0022 Revision 1 (or later FAA-approved revision) is terminating action for that repetitive lubrication requirement (Background; Amendment 1; Amendment 3).

• Duty to use FAA-approved AMOC for later revisions. The AD permits reliance on later revisions only if the FAA has approved them as AMOCs. Operators choosing to rely on a later ASB or SB revision must obtain or rely upon FAA approval for that revision to be considered compliant with the AD (Applicability; Requirement).

Rights and procedural points. The AD gives operators and their authorised representatives the right to use later revisions of the referenced Boeing documents, but only with FAA approval as an AMOC. That is described explicitly: "or later revision approved by the FAA as an alternative method of compliance (AMOC)" (Applicability; Requirement). The text therefore recognises an avenue for using newer Boeing documents, subject to FAA discretionary approval.

The AD’s Compliance clause constrains the operator’s duty to the times set in Paragraph 1.E of Boeing ASB 717-27A0016 Revision 2, so operators’ scheduling obligations are linked to that external document. The AD also provides a clear terminating path: once the operator accomplishes Boeing SB 717-27-0022 Revision 1 (or later FAA-approved revision), the repetitive lubrication requirement no longer applies (Requirement; Amendment 3). This creates a change in ongoing duties conditional on completion of a particular SB.

What the AD does not specify. The supplied text does not set out inspection protocols for compliance verification, does not specify a record-keeping regime, and does not state civil or criminal penalties for non-compliance. Nor does it state whether CASA will issue further directions or accept non-FAA AMOCs. Those matters are left unspecified in the supplied instrument. The AD’s requirements are written as instructions to "action in accordance with" specified Boeing documents; procedural rights and remedies other than the FAA AMOC pathway are not described in the text given (Requirement; Compliance).

The supplied text of this AD does not spell out penalties, sanctions, or enforcement procedures. The document contains the Requirement and Compliance provisions that create mandatory technical obligations , "Action in accordance with the requirements of Boeing ASB 717-27A0016 Revision 2" and compliance "As specified in Paragraph 1.E of Boeing ASB 717-27A0016 Revision 2" , but it does not include any clause stating the consequences for failing to comply with those obligations, nor does it identify administrative, civil or criminal penalties in this text (Requirement; Compliance).

The AD does, however, identify the instrument’s authorising delegate: Mike Higgins, Delegate of the Civil Aviation Safety Authority, with a signature dated 1 April 2010 and an effective date of 9 April 2010 (signature block). That identifies who issued the AD within the regulatory agency for the record. The AD also references FAA AD 2001-18-11 Amdt 39-12437 (Requirement, Note) and embeds FAA approval as the pathway for AMOCs for later revisions. The inclusion of the FAA approval requirement suggests that compliance determinations and acceptance of alternative methods are to be made in coordination with the FAA, though the AD does not in this text set out how CASA will handle non-compliance or disagreements about AMOCs.

Because the AD relies on external service documents for the detailed actions and timing (ASB Paragraph 1.E), enforcement in practice would hinge on confirming that the operator performed the specified ASB work within the required timeframes and that any terminating action was completed in accordance with an FAA-approved SB. The AD text does not describe mechanisms for that confirmation, nor does it state whether CASA inspectors will audit compliance or what records must be held. Those enforcement mechanisms, if present, are not contained in the supplied AD text.

If an operator wishes to use a revision of an ASB or SB that is not already accepted by the FAA, the AD makes FAA approval a precondition for that revision to count as an AMOC. The AD therefore channels disputes about acceptable methods to a process of FAA approval. The supplied text does not set out a CASA process for concurrence, appeals, or variances for Australian operators beyond naming the FAA approval requirement. In short, the AD prescribes mandatory technical duties, but the supplied material does not prescribe penalties or the procedural enforcement apparatus for non-compliance.

The AD cross-references and incorporates external technical documents and a prior FAA AD, which creates interplay between the AD and those other instruments. The AD requires "action in accordance with the requirements of Boeing ASB 717-27A0016 Revision 2, or later revision approved by the FAA as an AMOC" and identifies Boeing SB 717-27-0022 Revision 1 as a terminating action if it is approved by the FAA as an AMOC (Applicability; Requirement). This makes the Boeing ASB and SB a functional extension of the AD: operators must follow those manufacturer documents to comply with the AD. Therefore, those Boeing documents and any FAA approvals of their later revisions become part of the compliance landscape that operators must follow.

The AD expressly references FAA AD 2001-18-11 Amdt 39-12437 (Requirement, Note), indicating an existing FAA regulatory action related to the same or a similar unsafe condition. That reference situates the AD within an international regulatory framework and suggests that the CASA AD is coordinated with, or at least cognisant of, prior FAA action. The AD also makes FAA approval the gateway for later revisions to be accepted as AMOCs, positioning FAA decisions as determinative for allowable revisions in Australia under this instrument (Applicability; Requirement).

Domestically, the AD is issued by a delegate of the Civil Aviation Safety Authority. The AD does not in the supplied text state how it interacts procedurally with other Australian aviation legislation, such as the Civil Aviation Act or any enforcement regulations. The AD provides a technical mandate and effective date, but does not set out statutory enforcement mechanisms or administrative processes in this text. Any interplay with broader legislative enforcement powers, record-keeping obligations, airworthiness certification regimes, or penalties under Australian law is not articulated in the supplied AD.

Because the AD incorporates external manufacturer documentation and requires FAA approval for AMOCs, operators, maintenance organisations and regulators must coordinate across multiple instruments: the CASA AD itself, Boeing ASB 717-27A0016 Revision 2 (including Paragraph 1.E), Boeing SB 717-27-0022 Revision 1 for terminating action, and any FAA approvals or related FAA ADs such as FAA AD 2001-18-11. Those documents are thus part of the web of normative instruments that determine the scope of the obligations created by this AD.

The AD text contains an internal amendment narrative describing three amendments and the specific changes attributed to each. The history as set out in the supplied text is as follows:

• Original AD (implicit). The original AD addressed the rudder trim control system due to reports of in-flight binding and stiff operation, and set out the baseline requirement to act in accordance with Boeing ASB 717-27A0016. The Background explains the safety rationale relating to insufficient clearance in certain actuators that could allow moisture to condense and freeze, causing stiff operation or jamming of the rudder trim control system and potentially the rudder (Background).

• Amendment 1. Amendment 1 was issued "in response to a revision of the requirement document, which introduced additional aircraft." The Background further notes that Amendment 1 also introduced "an initial and repeat requirement to lubricate the actuator assembly." That indicates Amendment 1 expanded the list of affected aircraft and added a repetitive maintenance task (Background).

• Amendment 2. Amendment 2 allowed incorporation of revision 2 of the service bulletin, or later revisions, provided they had been approved by the FAA as acceptable AMOCs. The specific phrasing in the AD is that Amendment 2 "allowed the incorporation of revision 2 of the service bulletin or a later revision, providing it has been approved by the FAA as an acceptable alternative method of compliance." Amendment 2 is said not to have changed the compliance times (Background).

• Amendment 3. The current instrument is Amendment 3, and the text explains its change: "Amendment 3 is issued to introduce SB 717-27-0022 Revision 1 as an AMOC and terminating action for the repetitive lubrication requirement of ASB 717-27A0016 Revision 2." The Requirement section echoes that compliance with SB 717-27-0022 Revision 1, or later FAA-approved revision, is terminating action for the repetitive lubrication requirement of ASB 717-27A0016 Revision 2 (Requirement; Amendment 3).

Dates in the AD. The AD states "This Amendment becomes effective on 9 April 2010" and is signed by Mike Higgins, Delegate of the Civil Aviation Safety Authority, on 1 April 2010 (Compliance; signature block). The AD also lists "7/2010" in its header line with the AD identification data, although the effective date in the body is 9 April 2010.

Reference to prior FAA AD. The AD includes a Note referencing "FAA AD 2001-18-11 Amdt 39-12437" (Requirement, Note). That positions the AD within the lineage of regulatory responses to the same condition, but the AD text does not provide further details of that FAA AD beyond the citation.

Summary. The amendment history in the supplied text records the evolution from an initial AD addressing actuator clearance and lubrication, to a broadened applicability and explicit repetitive lubrication instruction in Amendment 1, to a relaxation of document rigidities in Amendment 2 by allowing later FAA-approved revisions as AMOCs, culminating in Amendment 3 which identifies a specific SB as terminating action for the repetitive maintenance requirement. The AD text itself records those steps; full detail about what each ASB or SB revision contains must be obtained directly from the Boeing documents cited.

The supplied AD text contains no litigation history. It does not reference any court decisions, administrative appeals, or legal challenges to this AD, its amendments, or to the referenced Boeing documents. The body of the AD lists a Note referencing FAA AD 2001-18-11 Amdt 39-12437, but that is a regulatory cross-reference and not a litigation citation (Requirement, Note).

Because no litigation or dispute record appears in the supplied instrument, there are no source-based findings about judicial interpretation, challenges to the AD’s validity, or precedent concerning compliance disputes. The AD does not contain procedural directions about appeals, reviews or dispute resolution mechanisms within its text. Any such litigation history, if it exists, is not contained in the material supplied here.

If readers require litigation or administrative law history related to this AD or the same technical issue, they will have to consult CASA records, FAA records, or court and tribunal databases for actions that are not reflected in this AD text. The AD itself gives no information about enforcement proceedings, contested AMOCs, or judicial review of this instrument.

The AD contains several concrete features and dependencies that can create practical pitfalls if misunderstood. The following items summarise those operational "gotchas" using only the supplied text.

• Applicability is by reference to an external ASB list. The AD does not list aircraft models or serials directly; it applies to "Model 717 series aircraft, as listed in Boeing Alert Service Bulletin (ASB)717-27A0016 Revision 2, or later FAA approved revision." Operators must consult the ASB to determine whether a particular aeroplane is included. Failing to consult the ASB could lead to misapplied obligations (Applicability).

• Compliance obligations are located in Paragraph 1.E of the ASB. The AD’s Compliance clause ties required times and actions to Paragraph 1.E of Boeing ASB 717-27A0016 Revision 2. Therefore, the AD requires knowledge of and adherence to specific paragraphs within an external document rather than prescribing times directly in the AD. Operators must obtain and follow the ASB Paragraph 1.E to know the exact timing and specifics of the required work (Compliance).

• FAA approval requirements for later revisions. The AD allows later revisions only if approved by the FAA as an AMOC. That is not optional in the AD text. Operators wishing to rely on a later revision must ensure FAA AMOC approval is in place, otherwise the ASB or SB revision will not qualify under this AD (Applicability; Requirement).

• Termination of repetitive lubrication is conditional. Amendment 3 makes Boeing SB 717-27-0022 Revision 1 an AMOC and a terminating action for the repetitive lubrication requirement. That means the repetitive lubrication duty remains in force "until accomplishment of Boeing SB 717-27-0022 Revision 1" or later FAA-approved equivalent. Operators must both accomplish the SB and ensure that the SB revision relied upon is approved as an AMOC by the FAA to secure the terminating effect (Requirement; Amendment 3).

• Multiple revisions and document versions matter. The AD refers to ASB Revision 2 and SB Revision 1 by name and permits later FAA-approved revisions. Operators must be careful to track which revision of each Boeing document they are using and whether the FAA has approved later revisions as AMOCs. Using a later Boeing revision without FAA AMOC approval does not meet the AD as written (Applicability; Requirement).

• The AD refers to a safety risk caused by insufficient clearance and moisture freeze. The Background explains the defect: "approximately 60 rudder trim and load-feel actuators were manufactured with insufficient clearance between the actuator support seal and spring capsule assembly" and that "Moisture condensing in the area of those components could freeze and cause stiff operation, binding, or jamming of the rudder trim control system and may cause jamming of the rudder." This pinpoints the mechanical defect to specific actuator components and therefore directs where inspection, lubrication or repair work must focus, but the AD itself delegates the precise rectification to the ASB and SB (Background).

• The AD does not state penalties, enforcement procedures, or record-keeping requirements. The absence of explicit enforcement and record-keeping steps in this text does not remove those obligations that may exist elsewhere under applicable aviation law, but it is a practical gotcha: compliance as set out must be demonstrable, yet the AD does not provide the form of proof or the CASA processes to be used (Requirement; Compliance).

• Cross-jurisdictional approval reliance. The AD makes FAA approval of later revisions a precondition for their use in Australia under this AD, so operators must coordinate with FAA processes and documentation even though the AD is a CASA instrument. That adds administrative complexity that might not be apparent if one reads the AD superficially (Applicability; Requirement).

These are direct operational and compliance pitfalls signalled within the supplied text. Each requires obtaining and reading the referenced Boeing ASB and SB, tracking revision status and FAA AMOC approvals, and scheduling maintenance consistent with Paragraph 1.E of the ASB until the terminating SB is accomplished and accepted.

The AD defines compliance by reference. The steps below translate the AD’s requirements into a compliance checklist grounded only in the AD text.

1. Establish applicability by consulting Boeing ASB 717-27A0016 Revision 2, or a later revision approved by the FAA as an AMOC (Applicability). Do not assume applicability from model type alone; check the ASB list to confirm whether each specific aeroplane is listed.

2. Obtain Boeing ASB 717-27A0016 Revision 2 and read Paragraph 1.E. The AD specifies that compliance is "As specified in Paragraph 1.E of Boeing ASB 717-27A0016 Revision 2" (Compliance). That paragraph contains the compliance intervals and specifics you must follow. Implement the tasks and timing exactly as set out there.

3. Implement the initial and repeat lubrication requirement. Amendment 1 introduced an initial and repeat lubrication requirement for the actuator assembly; until terminating action is taken, perform those lubrication actions at the intervals and according to the procedures specified in the ASB (Background; Amendment 1).

4. Track AMOC status for later revisions. If you plan to use a later revision of ASB 717-27A0016 or SB 717-27-0022, ensure that the FAA has approved that revision as an AMOC before treating it as compliant with this AD. The AD expressly conditions the use of later revisions on FAA approval as an AMOC (Applicability; Requirement).

5. Achieve terminating action by accomplishing Boeing SB 717-27-0022 Revision 1, or a later revision approved by the FAA as an AMOC. Amendment 3 specifies that doing so is terminating action "for the repetitive lubrication requirement of ASB 717-27A0016 Revision 2" (Requirement; Amendment 3). Ensure the SB work is performed to the standards and instructions in the SB and that FAA approval as an AMOC is in place where required.

6. Record the work and the revision versions used. While the AD text does not set out a record-keeping format, practical compliance requires that you document the ASB and SB revision numbers, the FAA AMOC approvals relied upon, the dates on which Paragraph 1.E actions were completed, and the date on which SB 717-27-0022 Rev 1 (or later FAA-approved revision) was accomplished so that the termination of repetitive lubrication can be demonstrated (Requirement; Compliance; Amendment 3).

7. Coordinate with FAA approvals where necessary. Because the AD mandates FAA approval for later revisions to qualify as AMOCs, follow FAA processes to obtain or confirm AMOC approvals for any document revision you intend to use. Do not assume a later Boeing ASB or SB revision is acceptable until FAA AMOC approval is confirmed (Applicability; Requirement).

8. Maintain awareness of AD effective dates and amendments. The AD states an effective date of 9 April 2010 and is signed by a CASA delegate on 1 April 2010. Amendment 3 introduced the SB as the terminating action; ensure your compliance timeline reflects that amendment status and the effective date of this version of the AD (Compliance; signature block; Amendment 3).

9. Ensure maintenance personnel follow the exact technical steps in the ASB and SB. The AD delegates technical detail to those documents; compliance requires implementation of those technical steps as written. Do not substitute alternative technical methods unless you have an FAA-approved AMOC for that alternative revision or method (Requirement; Applicability).

10. Monitor for any further amendments or FAA AD changes. The AD’s evolution through Amendments 1-3 demonstrates that the specific obligations can change over time. While the AD permits later FAA-approved revisions as AMOCs, the AD text itself is a snapshot effective from 9 April 2010. Maintain an ongoing monitoring process for ADs, ASBs and SBs that are relevant to the aircraft you operate so that compliance remains current (Amendment 1; Amendment 2; Amendment 3).

Following these steps will align an operator’s activity with the requirements and termination conditions set out in the AD text. The AD’s structure places primary operational obligations in Boeing’s ASB and SB documents and conditions acceptance of later revisions on FAA AMOC approval, so compliance is largely a matter of correctly implementing and documenting those manufacturer instructions and the FAA approval status of the revisions used.