AD/FSM/31 Amdt 3 - Fuel Injection Servo Plugs

The AD addresses a discrete airworthiness hazard: fuel injection servo plugs (P/N 383493) that can loosen or back out of the regulator cover, potentially causing a lean-running condition and substantial power loss. The AD supplies a duty framework to detect, correct and terminate the defect through inspection, replacement of an identified gasket part, increased clamp torque and secure safety-wiring.

Key technical concepts in the AD text:

• Part-numbered components. The AD distinguishes between two gasket part numbers: the older gasket P/N 365533 and an improved metal-backed gasket P/N 2577258. It treats P/N 365533 as ineligible and requires replacement with P/N 2577258 as the terminating action (Requirement 2(e), Requirement 3, Requirement 4).
• Inspection by hand-rotation. The primary detection method is an operational test of looseness: attempt to turn the servo plug by hand without damaging safety wire or seal; movement indicates looseness (Requirement 1).
• Dimensional/tolerance check. If the plug is removed, the servo plug outer diameter threads must measure within 0.7419-0.7500 inch (18.84-19.05 mm) and thread surfaces must show no burrs or chips; servos with threads outside those limits or with damage are condemned and must be replaced before flight (Requirement 2(c)-(d)).
• Retorquing to a higher clamp-up torque. The AD specifies a new, higher torque for the servo plug, 90-100 in-lbs, to maintain clamp-up force between plug and cover (Requirement 2(h)).
• Safety-wiring specifications. The servo plug must be safety wired to the regulator cover screws using wire of 0.015-0.025 inch diameter, in accordance with the MSB (Requirement 2(i)). Other safety wires on the servo must be inspected and any damaged wires replaced (Requirement 2(j)).
• Marking for eligibility. While the plug is removed, the face of the hex plug must be stamped or scribed with the letter “G” in accordance with PRS-107 Revision 4, indicating eligibility and the presence of the improved gasket (Requirement 2(f)).
• Compliance intervals and terminating action. Initial inspection is required before further flight after 23 February 2009 unless already done; repeat inspections are required at every engine oil change or every 50 flight hours (whichever is earlier) until the improved gasket P/N 2577258 is installed (Compliance). The mandatory terminating action is replacement of all P/N 365533 gaskets with P/N 2577258 by 31 December 2009 (Requirement 3, Compliance).
• Cross-jurisdictional conformity. The AD accepts later MSB revisions if approved by the FAA as AMOC to FAA AD 2009-02-03 (the AD notes equivalence to FAA actions), and it cites FAA ADs for reference (Note 1, paragraph under Requirement 4).

Operationally, the AD creates a move from monitoring to permanent modification: repeated inspections are a stopgap until the installation of the metal gasket and rework (torque, safety-wire, marking) provides the mandated terminating action. The AD also expands applicability to servos received for installation on or after 22 August 2006 that lack a P/N 2577258 gasket and do not have the “G” mark, and to servos where installation history is unknown (Applicability). The background section explains the observed failure mode (18 FAA reports of plugs loosening or backing out), the material differences between the gaskets (paper/fibre impregnated vs metal with synthetic rubber), and recalls the chronology of prior AD amendments.

The AD expressly directs "the registered operator of an aircraft fitted with an aeronautical product to which this AD applies" to carry out the inspection and corrective steps (Requirement 1 opening sentence). That phrasing identifies the primary duty-holder: the registered operator of the aircraft on which an affected fuel injection servo is installed.

Affected parties and roles that the AD implicates:

• Registered operators. They must perform or arrange the inspections required by Requirement 1, repeat them at the prescribed intervals until the terminating action, and ensure Requirement 2 actions are taken if loosening is detected. Requirement 3 makes replacement of the gasket P/N 365533 with P/N 2577258 a mandatory terminating action; operators must ensure that replacement is completed by the deadline.
• Maintenance personnel and workshops. The AD requires hands-on disassembly, thread inspection and measurement, installation of a new gasket, stamping/scribing the plug, torquing to a specified value (90-100 in-lbs), and safety‑wiring using specified wire diameters (Requirement 2(a)-(j)). These are maintenance activities that fall within the scope of licensed maintenance organisations and technicians. They must also assess thread condition and measure thread OD within the specified tolerance (0.7419-0.7500 inch).
• Parts suppliers and installers. The AD prohibits installation of the older gasket P/N 365533 after 23 February 2009 (Requirement 4). Any party installing gaskets or selling parts for servos used in Australia must be aware that P/N 365533 is ineligible and that P/N 2577258 is required for compliance.
• Pilots in command. Note 2 provides that a special flight permit may be issued to reposition an aircraft for compliance with Requirement 1 following a specified check of the servo plug by the pilot in command. The pilot is therefore given a procedural role limited to performing the specified check for repositioning. The AD explicitly bars special flight permits for compliance with Requirements other than Requirement 1.
• Aircraft registrars and compliance auditors. While not named, the AD’s existence makes it relevant to any airworthiness review; whoever is responsible for ensuring airworthiness directives are complied with for a registered aircraft must include these requirements in maintenance schedules until the terminating action is completed.
• Manufacturers and service bulletin authors. The AD references Precision Airmotive Mandatory Service Bulletin PRS-107 Revision 4 (16 July 2008) and accepts later MSB revisions approved by the FAA as AMOC. That links the AD’s acceptable methods directly to the manufacturer’s documented procedures.

Geographic and equipment scope is specified in the Applicability paragraph: the AD applies to certain Lycoming, Teledyne Continental, and Superior Air Parts engines fitted with the specified servo models with a P/N 365533 gasket installed on or after 22 August 2006; it also applies to servos received for installation on an engine on or after 22 August 2006 without a P/N 2577258 gasket and without the letter “G” on the servo plug, and to servos with unknown installation history. This produces a broad group of affected aircraft where the installation history is uncertain or where the older gasket was used after 22 August 2006.

The AD does not name CASA, the FAA, or other authorities as liable for costs. It does not specify monetary penalties or criminal sanctions in the text; compliance obligations are couched as mandatory ("must") duties imposed on the registered operator and installers, with timing and procedural prescriptions. The AD also notes that compliance with the previous amendment constitutes compliance with this amendment, which affects operators who already complied with earlier versions.

The AD uses mandatory language and enumerates precise duties for operators and persons who work on the affected servos. Key duties are:

• Inspect for looseness (Requirement 1). The registered operator must inspect the fuel injection servo plug P/N 383493 for looseness by attempting to turn it by hand, being careful not to damage the safety wire or seal. If the plug is loose, Requirement 2 applies. If not loose, the operator must repeat the inspection at each engine oil change or every 50 flight hours, until the P/N 365533 gasket is replaced with P/N 2577258 (Compliance, Requirement 1).

• Take remedial actions when looseness is found (Requirement 2). If looseness is detected, the registered operator must carry out a sequence of actions before further flight: remove only the safety wire spanning between the servo plug and regulator cover (2(a)); remove the servo plug and the P/N 365533 gasket (2(b)); examine threads for damage and measure the servo plug thread OD to 0.7419-0.7500 inch (2(c)); if threads are damaged or out of tolerance, the servo must not be installed and must be replaced prior to flight (2(d)); replace the gasket with P/N 2577258 (2(e)); stamp or scribe letter “G” onto the hex plug face in accordance with PRS-107 Revision 4 (2(f)); avoid installing any servo plug or regulator cover that is not eligible for installation, install new gasket P/N 2577258 and reassemble (2(g)); torque the servo plug to 90-100 in-lbs (2(h)); safety-wire the servo plug to the regulator cover screws using wire 0.015-0.025 inch diameter per the MSB (2(i)); inspect all other safety wires and replace damaged ones (2(j)).

• Perform the terminating action (Requirement 3). The mandatory terminating action for repetitive inspections is replacement of all P/N 365533 gaskets installed on servos affected by the AD with P/N 2577258 gaskets, following the detailed steps in Requirement 2(a)-(j).

• Prohibition on installing old gasket (Requirement 4). After 23 February 2009, a person must not install a gasket P/N 365533 onto any fuel injection servo.

Rights, limitations and compliance pathways enumerated in the AD:

• Acceptance of later MSB revisions as AMOC. The AD expressly states that later revisions of PRS-107 approved by the FAA as Alternate Methods of Compliance to FAA AD 2009‑02‑03 are acceptable for compliance with the equivalent requirements of this AD. This provides an avenue for operators to follow an updated manufacturer procedure, provided FAA approval as AMOC exists (paragraph following Requirement 4).

• Special flight permit for limited repositioning. Note 2 allows a special flight permit to reposition aircraft for compliance with Requirement 1 following a specified check by the PIC; the AD explicitly disallows special flight permits for compliance with any other requirements.

• Equivalence to prior compliance. The AD states that compliance with the previous amendment constitutes compliance with this amendment. That preserves prior compliance status for operators who acted under earlier AD versions.

Duties are precise and technical in nature, specifying part numbers, measurement tolerances, torque values, wire diameters, and stamping standards. The AD does not provide an appeals mechanism, nor does it specify rights to authorise alternative actions except by referring to the AMOC process via FAA-approved MSB revisions. The AD’s mandatory language creates obligations that are operationally allocated to the registered operator and the maintenance function that the operator engages.

The AD text itself does not set out criminal or civil penalties or an enforcement regime; it is an instrument issued under subregulation 39.001(1) of CASR 1998 and subsection 33(3) of the Acts Interpretation Act 1901, as set out in the opening paragraph. The AD uses mandatory terms ("must") that create enforceable maintenance and inspection obligations for registered operators and persons who install parts, but the instrument does not include a penalty schedule or specify enforcement steps within the document.

What the AD does state that is relevant to enforcement mechanics and legal effect:

• Source of authority. The AD is issued under an express statutory/regulatory delegation: subregulation 39.001(1) of CASR 1998 and subsection 33(3) of the Acts Interpretation Act 1901 are cited in the opening paragraph. This situates the AD within CASA’s statutory power to issue airworthiness directives, but the AD text does not reproduce those regulatory provisions or specify how contraventions will be treated under applicable law.

• Mandatory obligations. The repeated use of "must" throughout Requirements 1-4 creates binding duties for the identified parties (registered operators and persons installing gaskets); the AD sets specific timing for inspections and mandated work before further flight in certain circumstances (Requirement 2, Compliance).

• Cross-reference to FAA AD and MSB AMOC. The AD references FAA AD 2009-02-03 and accepts FAA‑approved alternate methods of compliance via later MSB revisions. That cross-reference suggests that compliance may be demonstrated by adherence to FAA-approved procedural changes, but the AD remains the Australian mandate.

• Special flight permit limitations. The AD permits a special flight permit to reposition an aircraft only for compliance with Requirement 1 and not for other requirements. That constraint limits operational leeway for operators seeking to defer or perform corrective work in-air or at remote locations, and bears on enforcement insofar as flight without complying with Requirements beyond what the permit allows would depart from the AD’s conditions.

Because the AD document does not detail penalties or enforcement mechanisms (for example, administrative fines, grounding, or prosecution), parties who need to understand the consequences of non-compliance must refer to CASR and other regulatory instruments that govern enforcement of AD compliance. The AD’s own statement that it is an instrument under the cited regulation is the closest available indicator of the legal basis for enforcement, but specific penalty provisions are not contained in the AD text provided.

This AD is positioned in the regulatory framework by explicit cross‑references and by operational interaction with manufacturer service literature and FAA actions. The AD itself states the legal base and identifies other documents with which it interlocks:

• Enabling regulation cited. The AD is issued under subregulation 39.001(1) of CASR 1998 and subsection 33(3) of the Acts Interpretation Act 1901 (opening paragraph). The AD does not reproduce or interpret those provisions, but it identifies them as the statutory/regulatory authority for issuing the directive.

• Interaction with FAA ADs and manufacturer service bulletin. The AD cross‑references FAA AD 2009‑02‑03 (which supersedes FAA AD 2008‑08‑14) and refers to Precision Airmotive Mandatory Service Bulletin PRS‑107 Revision 4 dated 16 July 2008 (the MSB) as the procedural source for certain actions, including stamping the "G" marking and safety-wiring procedures (Requirement 2(f), 2(i)). The AD accepts later MSB revisions approved by the FAA as alternate methods of compliance to FAA AD 2009‑02‑03, and states those later MSB revisions are acceptable for compliance with the equivalent requirements of this AD. That creates a compliance pathway tied to FAA approvals and the manufacturer’s service documentation rather than to an independent Australian technical standard.

• Relationship to prior AD amendments. The AD revokes AD/FSM/31 Amdt 2 and notes that compliance with the previous amendment constitutes compliance with this amendment. It also records prior amendments (Amdt 1, Amdt 2) and their technical changes. This indicates continuity among successive regulatory instruments and that earlier compliance actions satisfying prior ADs remain valid under the current amendment.

• Interplay with maintenance and airworthiness regimes. Although the AD does not explicitly cite CASR maintenance obligations, by applying to the registered operator and requiring specified maintenance actions, it functions as an airworthiness requirement to be observed within the operator’s maintenance control framework and maintenance records. The AD’s mandates , inspection intervals tied to engine oil changes, torque values, part-number prohibitions, and stamping , are the type of content that maintenance organisations must incorporate into their procedures and records.

• Special flight permit practice. The AD allows a special flight permit to reposition an aircraft for compliance with Requirement 1 following a specified check by the pilot in command but does not permit a special flight permit for other requirements. That interacts with whatever statutory or regulatory process governs issuance of special flight permits, limiting their availability to repositioning for this very specific purpose.

• International conformity. The AD’s explicit reliance on FAA ADs and acceptance of FAA-approved MSB revisions as AMOC establishes an operational link with the FAA regulatory regime and indicates a willingness to accept FAA-authorised procedures as evidence of compliance in Australia. That aligns manufacturer and FAA actions with CASA’s enforcement expectations in this technical area.

The AD does not provide further detail on how it should be reconciled with other specific Australian statutes, regulations, or administrative processes (for example, how non‑compliance would be prosecuted under CASR, or interaction with insurance or contractual obligations), nor does it define the administrative process for demonstrating compliance other than referring to the MSB and FAA AMOC. Users seeking the enforcement or penalty consequences or procedural steps for appeals or alternative compliance should consult CASR and CASA guidance beyond the AD text.

The AD contains a concise recorded amendment path in its Background and opening paragraphs. The sequence and the changes are referenced as follows:

• AD/FSM/31 (original). The AD family traces back to AD/FSM/31, which became effective on 14 March 2008. According to the Background, the original AD was intended to prevent a lean running engine caused by servo plug loosening, which could result in substantial power loss and loss of control.

• AD/FSM/31 Amdt 1. Amdt 1 became effective on 9 May 2008. The Background states that Amdt 1 included an alternative means of compliance and terminating action as detailed in Precision Airmotive Service Bulletin PRS‑107. The service bulletin provided for different inspection intervals and a terminating action to end repeat inspections.

• AD/FSM/31 Amdt 2. Amdt 2 became effective on 23 February 2009. The Background states that Amdt 2 made changes to the applicability section to clarify Teledyne Continental engine models and to include Bendix RSA‑5 and RSA‑10 servos. It also added replacement and fitment requirements associated with gasket P/N 365533.

• AD/FSM/31 Amdt 3 (this document). Amdt 3, effective 18 October 2013, is described in the AD as making an editorial correction to the associated FAA AD references and other editorial changes. The AD expressly states there is no technical change to the requirements and no change to compliance from the previous amendment. Furthermore, the AD clarifies that compliance with the previous amendment constitutes compliance with this amendment.

The AD’s Background describes the technical trigger for the AD family: 18 FAA reports of servo plugs that had loosened or completely backed out of the threaded plug hole on the regulator cover. It contrasts the materials of the two gaskets: P/N 365533 (paper or fibre material impregnated with synthetic rubber, relatively flexible and rough surface) versus P/N 2577258 (metal with synthetic rubber coating, relatively rigid and smooth surface). The AD’s text thus ties the amendment history to a sequence of detections, service bulletin issuance, and expanded applicability, culminating in Amdt 3 which records only editorial correction rather than substantive change.

The AD also notes the FAA AD chronology for reference: FAA AD 2008‑08‑14 was superseded by FAA AD 2009‑02‑03 Amdt 39‑15793 dated 13 January 2009 (Note 1). The AD accepts later MSB revisions approved by the FAA as AMOC to FAA AD 2009‑02‑03, linking the Australian amendments to FAA administrative history.

The AD text does not include or reference any litigation history. There are no court decisions, administrative reviews, or enforcement proceedings recorded in the document. The AD states its issuance, effective date, prior amendments and the technical background but does not mention any disputes, appeals, or legal challenges to any iteration of the AD.

Because the document does not record litigation, a reader who requires information on any judicial or administrative challenges to the AD will need to consult external sources such as court registries, administrative review bodies, or CASA records beyond the AD text itself. The AD does, however, make a procedural note that compliance with the previous amendment constitutes compliance with this amendment, which removes at least one avenue for dispute about whether older compliance remains effective under the present amendment.

In short, the AD contains no litigation history or references to cases, and it does not identify any contested legal outcomes relating to its requirements in the provided text.

Several operational and legal “gotchas” arise from the AD’s precise technical requirements and its combination of dates, part numbers and cross‑references. The AD text supplies the material facts; these are the specific areas where parties commonly misread or overlook obligations:

• Dates in the AD are historic yet binding in wording. The Compliance section requires inspections "before further flight after 23 February 2009" for Requirement 1 unless already done, and prescribes that the terminating action (Requirement 3) must be done "by 31 December 2009." But the AD’s effective date is 18 October 2013. Read literally, the AD confirms that operators were expected to have complied by the earlier dates; the AD also states that compliance with the previous amendment constitutes compliance with this amendment. Operators should therefore verify historical compliance records, because the AD’s language preserves earlier deadlines as the required target dates and treats prior compliance as satisfying the present AD (Compliance; the AD’s final paragraphs on continuity). Confusion may arise for operators who assume the effective date alone sets new timeframes.

• Applicability includes servos with unknown installation history. The Applicability extends to any RSA‑5/RSA‑10 or Bendix RSA‑5/RSA‑10 servo "if the installation history of the fuel injection servo is not known." That widens the net to any servo where provenance is uncertain. Operators or purchasers of second‑hand servos should not assume absence of the P/N 365533 gasket; when history is unknown the AD applies.

• Part-number and marking interplay. The AD applies when a P/N 365533 gasket was installed on or after 22 August 2006, and also to servos received for installation on or after 22 August 2006 without a P/N 2577258 gasket and without a letter "G" on plug P/N 383493 (Applicability). That means even servos installed before 22 August 2006 but later received for installation or with unknown history may be captured. The stamping of "G" (Requirement 2(f)) matters: once the "G" is present and the improved gasket is fitted, the servo is identifiable as eligible. Failure to correctly stamp/scribe the plug pursuant to the MSB, or to recognise the absence/presence of the "G", can lead to misclassification.

• Prohibition on installing P/N 365533 after 23 February 2009. Requirement 4 is an absolute prohibition (post‑23 February 2009) on installing gasket P/N 365533. Parts suppliers and maintenance shops must ensure old stock is not fitted inadvertently. The AD does not define exemptions or transitional arrangements.

• Technical measurement and workshop capability. Requirement 2(c) requires measurement of servo plug outer diameter thread within 0.7419-0.7500 inch (18.84-19.05 mm) and examination for burrs or chips; if threads do not meet these tolerances, the servo must not be installed and must be replaced. Not all maintenance providers may have the precision measurement tools or experience to perform the inspection to the specified tolerances. Operators must ensure maintenance providers can perform these checks or arrange appropriate replacement or refurbishment.

• Torque and safety-wire specifics. The AD mandates a new, higher torque (90-100 in-lbs) and safety-wire diameter (0.015-0.025 inch) and requires adherence to PRS‑107 for safety-wiring technique. Incorrect torque or incorrect safety‑wiring diameter or technique could leave the servo non-compliant even if other steps have been performed.

• Acceptable alternative compliance constrained by FAA approval. The AD allows later MSB revisions approved by the FAA as AMOC to FAA AD 2009‑02‑03 to be used for compliance, but only if the FAA has approved them. Operators relying on updated PRS‑107 revisions must verify FAA AMOC approval before assuming Australian compliance.

• Special flight permit narrowness. Note 2 permits only repositioning flights following a specified check by the pilot in command for Requirement 1. No special flight permit is permitted for any other requirements. Operators seeking to delay replacement or remote repair cannot rely on a special flight permit to defer all work.

• The AD is explicit on who must act. The duty language is directed to the "registered operator" (Requirement 1 opening). Parties other than the registered operator (for example, maintenance organisations or owners where ownership and registration differ) need clarity on who is responsible for compliance. The AD does not reassign duties to other roles.

• No penalties in the AD text. The AD does not state enforcement measures or penalties for non-compliance. Those must be sought in CASR and other legal texts; absence of penalties in the AD does not imply absence of enforcement risk.

• Editorial correction versus substantive change. Amdt 3 states it makes only editorial corrections to FAA AD references and that there is no technical change or compliance change from the previous amendment. Operators who already complied with Amdt 2 are treated as compliant with Amdt 3. However, careful cross‑checking is required to ensure that compliance demonstrably matches the Requirements as written (including stamping, torque, parts, and inspection intervals).

These are concrete procedural and interpretive pitfalls the AD text itself highlights. Operators should ensure maintenance records, parts stock, and service‑bulletin compliance evidence are in order to demonstrate fulfilment of the AD’s specific technical conditions.

The AD provides explicit step‑by‑step actions and timings. The following restates the AD’s precise compliance obligations and practical steps an operator should document and perform.

Initial applicability check

• Determine whether an aircraft’s engine and fuel injection servo fall within the Applicability list: Lycoming IO, (L)IO, TIO, (L)TIO, AEIO, AIO, IGO, IVO, and HIO series engines; Teledyne Continental LTSIO‑360‑RB and TSIO‑360‑RB engines; Superior Air Parts IO‑360 series engines, when fitted with a Precision Airmotive LLC RSA‑5 or RSA‑10 series, or Bendix RSA‑5 or RSA‑10 series, fuel injection servo that has gasket P/N 365533 installed on or after 22 August 2006, or any such servo received for installation on or after 22 August 2006 without gasket P/N 2577258 and without a letter "G" on the plug, or any servo with unknown installation history (Applicability).

Requirement 1 , inspection

• The registered operator must inspect the servo plug P/N 383493 for looseness by attempting to turn it by hand while taking care not to damage the safety wire or seal. If the plug moves, it is loose (Requirement 1).
• Timing: the initial inspection must be completed before further flight after 23 February 2009 unless already accomplished (Compliance). Until the improved gasket P/N 2577258 is installed, repeat the inspection at the earlier of every engine oil change or every 50 flight hours (Compliance).

If the plug is not loose:

• Repeat inspections as above until the mandatory terminating action is completed.

If the plug is loose , Requirement 2 (before further flight)

• Carefully cut and remove only the safety wire that spans between the servo plug and regulator cover (2(a)).
• Remove the servo plug and the gasket P/N 365533 behind the plug; note the gasket may be slightly adhered to the regulator cover (2(b)).
• Examine the threads on the servo plug and regulator cover for damage; threads must be smooth and consistent without burrs or chips (2(c)).
• Measure the servo plug outer diameter threads; the OD must be within 0.7419-0.7500 inch (18.84-19.05 mm) (2(c)). If the threads on the plug or regulator cover are damaged or do not measure within these limits, the servo must not be installed and must be replaced before further flight (2(d)).
• Replace the old gasket P/N 365533 with a new improved gasket P/N 2577258 (2(e)).
• While the hex plug is removed, stamp or scribe the letter "G" onto the face of the hex plug in accordance with Precision Airmotive MSB PRS‑107 Revision 4, 16 July 2008 (2(f)). Ensure the stamping/scribing matches the MSB’s guidance for location and legibility.
• When reassembling, do not install any servo plug or regulator cover that is not eligible for installation. Install the new gasket P/N 2577258 on the servo plug and reassemble the servo plug to the regulator cover (2(g)).
• Torque the servo plug to 90-100 in‑lbs to maintain proper clamp-up force between the plug and cover (2(h)). Use a calibrated torque wrench and record the torque value in maintenance records.
• Safety wire the servo plug to the regulator cover screws using wire with diameter between 0.015 and 0.025 inch in accordance with the MSB (2(i)). Follow the MSB for the method of safety-wiring and the number of twists, routing and anchorage points.
• Inspect all other safety wires on the servo and replace any that are damaged (2(j)).

Requirement 3 , terminating action

• The mandatory terminating action consists of replacing all gaskets P/N 365533 installed on servos affected by the AD with gasket P/N 2577258, carrying out all actions in Requirement 2(a)-(j) for each servo. The Compliance section states that the terminating action must be completed by 31 December 2009. Because this AD is an amendment that records prior deadlines, operators should ensure maintenance records demonstrate that such replacement either occurred by the specified date or that they complied with equivalent prior AD versions that the AD recognises as satisfying this amendment.

Requirement 4 , prohibition on installation

• A person must not install gasket P/N 365533 onto any fuel injection servo after 23 February 2009. Parties supplying or fitting gaskets must ensure that only P/N 2577258 is installed for affected servos.

Use of MSB and AMOC pathway

• Follow Precision Airmotive Mandatory Service Bulletin PRS‑107 Revision 4 (16 July 2008) for stamping and safety-wiring instructions; the AD accepts later revisions of the MSB that have been approved by the FAA as an AMOC to FAA AD 2009‑02‑03 (paragraph after Requirement 4). Operators using later MSB revisions must verify FAA approval as AMOC before relying on those revisions for Australian compliance.

Special flight permit

• A special flight permit may be issued to reposition an aircraft for compliance with Requirement 1 provided the repositioning follows a specified check of the servo plug carried out by the pilot in command (Note 2). No special flight permit can be issued for compliance with other requirements. Operators should coordinate with the issuing authority of special flight permits to ensure that the permit, if required, is consistent with the AD’s limitation.

Record keeping and evidence

• Document each inspection attempt (who performed it, date, findings), any disassembly/measurement, part-number replacements, torque readings, safety-wiring details (including wire size) and stamping of the “G.” Because the AD treats prior compliance under previous amendments as compliant with this amendment, ensure historical records show completion of the prior AD steps where applicable.

Replacement and procurement

• Ensure procurement channels supply the improved gasket P/N 2577258 and that spare or stock parts lists exclude P/N 365533 to avoid inadvertent installations. Maintenance organisations should update work cards and parts lists to reflect the prohibition in Requirement 4.

If threads are out of tolerance or damaged

• Do not reinstall the servo. Replace the servo before further flight (Requirement 2(d)). That replacement must be witnessed or recorded per maintenance practice so that airworthiness records demonstrate compliance.

Verification against FAA ADs and MSB

• Maintain copies of FAA AD 2009‑02‑03 and precision Airmotive PRS‑107 Revision 4 in maintenance technical files for reference. If relying on an FAA-approved AMOC via a later PRS‑107 revision, maintain evidence of FAA approval.

Practical sequence at maintenance event

1. On initial or scheduled inspection, attempt hand-rotation test of plug per Requirement 1.
2. If no movement, log inspection and schedule next inspection at oil change or 50 flight hours.
3. If movement occurs, ground aircraft for maintenance; remove specified safety wire and follow Requirement 2 steps (measurement, replacement of gasket, stamping, torque, safety-wiring).
4. Complete and sign maintenance release only when all Requirement 2 steps are met.
5. Replace all P/N 365533 gaskets across affected servos as terminating action and record completion per Requirement 3 (where applicable).

In sum, compliance requires a mix of record-checking (applicability and historic work), scheduled and condition-based inspections, workshop-level disassembly and measurement, parts replacement with specific part numbers, marking, torque and safety-wiring to the MSB standard, and retention of the compliance evidence. Operators should ensure maintenance staff have calibrated measurement equipment, appropriate torque tools and approved safety wiring materials, and that parts procurement and inventory control eliminate the ineligible gasket P/N 365533 from future installations.