AD/B747/386 - EFIS/ECAS Interface Units

This instrument is a focused equipment-mandate airworthiness directive. Its core concepts are:

• Applicability gating by service bulletin identification. The applicability block does not list all 747-400 series by registration or serial number; it identifies Model 747-400, 747-400D and 747-400F series aeroplanes "as identified in Boeing Service Bulletin 747-31-2368, Revision 1, dated 24 July 2006." That means the scope of affected tail numbers or serials is determined by the Boeing SB listed in the AD, not by an open textual list in the AD itself.

• A mandatory hardware substitution. The operative directive requires replacement of at least one of the three EFIS/EICAS EIUs (P/N 622-8589-104) located on the E2-6 shelf of the main equipment centre, with a new or modified EIU, P/N 622-8589-105. The AD ties performance of the replacement to the Accomplishment Instructions of Boeing SB 747-31-2368, Revision 1, dated 24 July 2006. The AD therefore prescribes both the physical change and the procedural source to accomplish it.

• Use of modification to add "auto restart" circuitry. Note 1 links to Rockwell Collins Service Bulletin EIU-7000-31-502, dated 21 March 2006, for "modifying an EIU by adding auto restart circuitry," and clarifies that that modification converts a P/N 622-8589-104 unit into a P/N 622-8589-105 unit. Mechanically, the AD thus accepts either factory-supplied P/N 622-8589-105 units or previously manufactured P/N 622-8589-104 units that have been modified into P/N 622-8589-105.

• Temporal compliance window. The AD sets a 24-month compliance window measured from the AD effective date (effective date 18 December 2008). It also addresses retroactivity by recognising actions performed before the effective date under an earlier Boeing SB (22 November 2005) as acceptable.

• Cross-reference to earlier ADs and terminating action conditions. The Directive creates a conditional interaction with prior directives: replacing an EIU per Requirement 1 is a terminating action for an EIU replacement requirement in AD/B747/308 or FAA AD 2004-10-05, but only where the other two EIUs are P/N 622-8589-104 or 622-8589-105. The Directive therefore alters the compliance obligations under earlier instruments, but only within a precisely stated factual pattern.

• Reliance on FAA approvals for later SB revisions and AMOC acceptance. The AD says that "Later revisions of the above SB(s), approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-22, are considered acceptable for compliance with the equivalent Requirements of this Directive." This establishes a narrow delegation of acceptability to FAA AMOC approvals for later SB revisions, rather than blanket acceptance of all later revisions.

• Safety motivation stated in the AD. The background records two incidents in which all six IDUs went blank in flight and states the hazard being addressed: simultaneous failure of all three EIUs leading to inability to maintain safe flight and landing. The AD links the hardware change to prevention of that hazard.

Those concepts define the AD’s mechanics: which aircraft are in scope, what physical change must be done, where to find the procedural instructions, what modifications qualify as equivalent, the deadline for compliance, and how this AD interacts with earlier directives and FAA AMOCs.

The Directive’s applicability clause names the aircraft types that fall within its scope: Model 747-400, 747-400D and 747-400F series aeroplanes, as identified in Boeing Service Bulletin 747-31-2368, Revision 1, dated 24 July 2006 ("Applicability" block). The AD therefore affects those 747-400 series aeroplanes that are specifically identified in that Boeing service bulletin; the AD does not include an independent listing in the text supplied.

Beyond the aircraft-level scope, the Directive places an action requirement on whoever is responsible for accomplishing the work specified by the AD. The text specifies the work to be done "in accordance with the Accomplishment Instructions of SB 747-31-2368, Revision 1," and it accepts Rockwell Collins Service Bulletin EIU-7000-31-502 as an additional source of service information for the modifying option. The AD does not name the specific person, organisation or class of organisations that must perform the replacement, nor does it state who pays for parts or labour. The AD also does not specify who certifies the work after completion. The only named issuer is James Coyne, Delegate of the Civil Aviation Safety Authority, and the AD is presented as a binding airworthiness directive.

Operationally, the parties that will practically be affected are those who own, operate, maintain or certify the affected aeroplanes, because the Directive requires a hardware change to aircraft equipment. The AD’s compliance timing and conditional relationship to AD/B747/308 and FAA AD 2004-10-05 mean that owners or operators whose aeroplanes are subject to those prior directives must pay attention to whether a replacement performed under AD/B747/386 will be treated as terminating action for earlier EIU-replacement obligations.

Parts suppliers and maintenance organisations will be implicated to the extent they supply or install P/N 622-8589-105 units or perform the Rockwell Collins modification that converts a 622-8589-104 into a 622-8589-105. The AD names specific part numbers and a specific equipment location (the E2-6 shelf of the main equipment centre), so personnel responsible for component identification and installation must ensure exact matches to the specified P/Ns and location.

The Directive’s references to Boeing SB 747-31-2368 and Rockwell Collins SB EIU-7000-31-502 make those service documents the procedural authority for accomplishing the work. The AD also states that earlier actions taken in accordance with Boeing SB 22 November 2005 are considered acceptable, so operators who already undertook the work per that earlier bulletin before the AD’s effective date will be treated as compliant for the corresponding requirements.

Finally, the Directive incorporates a constraint on acceptance of later revisions of the SBs: later revisions are acceptable only if they are approved by the FAA as AMOCs to FAA AD 2008-13-22. This affects operators who may wish to rely on later SB revisions; they must confirm FAA AMOC approval to rely on those later revisions as acceptable for compliance with this Directive.

The Directive sets a limited set of duties and a few limited rights (or acceptances) concerning acceptable compliance methods. The text supplies the duties and rights verbatim and ties them to service bulletin documents. Key duties and cross-acknowledged rights are as follows.

Primary duty: Replace at least one EIU part number 622-8589-104 with a new or modified EIU part number 622-8589-105, located on the E2-6 shelf of the main equipment centre, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 747-31-2368, Revision 1, dated 24 July 2006 (Requirement block). The duty is precise about part numbers and location and prescribes the Boeing SB as the procedural authority.

Timing duty: Comply with the replacement within 24 months after the AD’s effective date. The AD “becomes effective on 18 December 2008,” so the compliance window is concrete.

Right to use a modification as an equivalent: The AD’s Note 1 makes Rockwell Collins Service Bulletin EIU-7000-31-502, dated 21 March 2006, an "additional source of service information for modifying an EIU by adding auto restart circuitry, which converts EIU P/N 622-8589-104 to P/N 622-8589-105." That means the AD permits either installing factory P/N 622-8589-105 units or modifying existing P/N 622-8589-104 units according to the Rockwell Collins SB so as to obtain P/N 622-8589-105 functionality.

Retroactivity acceptance: The AD declares that "Actions accomplished before the effective date of this Directive in accordance with Boeing SB 747-31-2368, dated 22 November 2005 (Revision 1 of the service bulletin specifies that the original issue is dated 1 December 2005), are considered acceptable for compliance with the corresponding requirements of this Directive." Thus work completed before the AD’s effective date per the earlier Boeing SB is accepted, removing the need to redo that work.

Acceptance of later SB revisions only with FAA AMOC approval: The AD provides that "Later revisions of the above SB(s), approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-22, are considered acceptable for compliance with the equivalent Requirements of this Directive." This is a constrained right; operators may rely on later revisions, but only where those later revisions have that specific FAA AMOC approval.

Conditional terminating action for an earlier AD requirement: The AD states replacing an EIU per Requirement 1 "constitutes terminating action for the EIU replacement (Requirement 3 of AD/B747/308 or paragraph (d)(1) of FAA AD 2004-10-05)," but only if the other two EIUs are P/N 622-8589-104 or P/N 622-8589-105. The AD then specifies that "All other actions required by Requirement 1 of AD/B747/308 or paragraph (d)(1) of AD 2004-10-05 must be complied with." Thus the Directive modifies earlier obligations only within the explicit conditional facts.

Rights not expressed: The Directive does not state who is responsible for payment, who must certify the work, who decides acceptability beyond the FAA AMOC acceptance, or what documentation is required after completion. The AD is silent in the supplied text on enforcement mechanisms, penalties, or administrative processes for demonstrating compliance under CASA. Those matters are not contained in the text provided.

In sum, the Directive’s duties are concrete and narrow: identify applicability via Boeing SB Rev 1, replace at least one EIU P/N 622-8589-104 with P/N 622-8589-105 on the E2-6 shelf using the Boeing SB instructions, within 24 months. Rights or acceptances are limited to pre-effective-date compliance under an earlier Boeing SB, and to later SB revisions only if they have FAA AMOC approval. A conditional terminating effect on earlier ADs is explicitly stated, subject to the stated part-number condition and preservation of other required actions.

The text supplied for AD/B747/386 does not set out penalties, sanctions, or a specific enforcement process. The document records the mandatory technical requirement, the deadline for compliance, references to service bulletins, and links to prior ADs and FAA approvals, but it does not include any express monetary penalties, administrative fines, suspension mechanisms, or civil or criminal sanctions in the text provided.

The Directive does make clear that it is a formal airworthiness directive (titled AD/B747/386), that it "becomes effective on 18 December 2008," and that compliance must be achieved "within 24 months after the effective date of this AD." The Directive is signed by "James Coyne, Delegate of the Civil Aviation Safety Authority," dated 6 November 2008; the presence of the CASA delegate’s signature signals issuance by the regulator. However, the AD text as supplied does not explain how compliance will be evidenced, which agency action will be taken for non-compliance, or what penalties may apply where operators fail to comply.

The Directive cross-references FAA AD 2008-13-22 (Amdt 39-15585) and earlier AD/B747/308 and FAA AD 2004-10-05. Those references potentially implicate enforcement obligations under those prior directives, but the supplied text does not quote or summarise any enforcement provisions from those instruments. The AD does specify that replacement performed in accordance with Requirement 1 constitutes terminating action for an EIU replacement requirement in AD/B747/308 or FAA AD 2004-10-05, subject to the stated conditions. That affects legal obligations created by those prior ADs, but the AD text does not itself describe enforcement follow-up.

Because no direct penalty or enforcement language is contained in the supplied AD text, readers who require certainty about enforcement, penalties, or compliance-recording processes will need to consult CASA’s broader regulatory framework and procedures or the full AD issuance as published by CASA for any annexed enforcement provisions. The supplied AD text does not provide that information.

The AD text explicitly builds a narrow bridge between this instrument and pre-existing airworthiness directives and service bulletins; it does not reference broader statutes or other regulatory instruments in the supplied text. The explicit interactions set out in the Directive are:

• With FAA AD 2008-13-22. The AD contains a Note: "FAA AD 2008-13-22 Amdt 39-15585 refers." It also states that "Later revisions of the above SB(s), approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-22, are considered acceptable for compliance with the equivalent Requirements of this Directive." That means the AD anchors acceptability of later service bulletin revisions to FAA AMOC approval under FAA AD 2008-13-22. Concretely, an SB revision that is not approved by the FAA as an AMOC to FAA AD 2008-13-22 will not be treated as automatically acceptable under this Directive.

• With AD/B747/308 and FAA AD 2004-10-05. The Directive states that replacing an EIU pursuant to Requirement 1 "constitutes terminating action for the EIU replacement (Requirement 3 of AD/B747/308 or paragraph (d)(1) of FAA AD 2004-10-05)," provided the other two EIUs are of certain part numbers, specifically P/N 622-8589-104 or P/N 622-8589-105. It then clarifies that "All other actions required by Requirement 1 of AD/B747/308 or paragraph (d)(1) of AD 2004-10-05 must be complied with." Thus the Directive amends the compliance landscape produced by those earlier ADs, but only for the narrow EIU-replacement obligation and only when other parts meet the stated P/N condition.

• With Boeing Service Bulletin 747-31-2368. The AD’s applicability and procedural authority both refer to Boeing SB 747-31-2368, Revision 1, dated 24 July 2006. The SB defines which aeroplanes are affected and provides the Accomplishment Instructions that the AD makes mandatory for the replacement action. Earlier Boeing SB dated 22 November 2005 is also explicitly accepted for actions done before the AD’s effective date. The AD therefore relies on the Boeing SB for both scope and procedure.

• With Rockwell Collins Service Bulletin EIU-7000-31-502. The AD designates this Rockwell Collins SB as an "additional source of service information" specifically for converting P/N 622-8589-104 to P/N 622-8589-105 by adding auto restart circuitry. The AD therefore recognises that modification as equivalent to installing a factory P/N 622-8589-105 unit, provided the modification follows the Rockwell Collins SB.

These interactions create a compliance network: CASA’s AD sets the obligation, Boeing’s SB supplies the procedural steps and aircraft identification, Rockwell Collins’ SB provides an approved modification pathway, and FAA AMOC approvals to FAA AD 2008-13-22 determine whether later SB revisions will be acceptable for compliance.

The AD does not, in the supplied text, assert any supremacy rule or explicitly cite the enabling statute under which CASA issues ADs, nor does it quote any Australian Civil Aviation Act or regulation. It also does not identify how CASA will accept proof of compliance, how records will be maintained, or whether CASA will accept FAA AD compliance records as evidence. The only cross-jurisdictional delegation evident in the text is the conditional acceptance of FAA AMOC approvals to FAA AD 2008-13-22 as a basis for accepting later SB revisions.

Practically, the Directive modifies the requirements created by earlier AD/B747/308 and FAA AD 2004-10-05 only where the stated part-number condition holds. It therefore interacts with those older instruments by relieving an EIU-replacement obligation in that narrow factual pattern, while leaving all other obligations of Requirement 1 in those older instruments intact.

The AD text records a short amendment chronology and cross-references to service-bulletin revision dates. Key dates and revision references in the supplied text are:

• Boeing Service Bulletin (SB) 747-31-2368, Revision 1, dated 24 July 2006. This is the primary SB that the AD uses both to identify affected aeroplanes and to supply the Accomplishment Instructions for the required replacement. The AD’s "Applicability" block explicitly ties affected aeroplanes to those "as identified in Boeing Service Bulletin (SB) 747-31-2368, Revision 1, dated 24 July 2006."

• Earlier Boeing SB dated 22 November 2005. The AD states that "Actions accomplished before the effective date of this Directive in accordance with Boeing SB 747-31-2368, dated 22 November 2005 (Revision 1 of the service bulletin specifies that the original issue is dated 1 December 2005), are considered acceptable for compliance with the corresponding requirements of this Directive." That records an acceptance of prior compliance under the earlier Boeing SB and notes the original issue date of the Revision 1 SB.

• Rockwell Collins Service Bulletin EIU-7000-31-502, dated 21 March 2006. This SB is listed in Note 1 as an additional source of service information for modifying EIUs by adding the auto restart circuitry that converts P/N 622-8589-104 to P/N 622-8589-105.

• FAA AD 2008-13-22 Amdt 39-15585. The AD includes a Note that refers to FAA AD 2008-13-22 and conditions acceptance of later revisions of the listed SBs on FAA approval of those revisions as AMOCs to FAA AD 2008-13-22.

• Prior ADs referenced for terminating action purposes: AD/B747/308 and FAA AD 2004-10-05. The AD references these earlier directives and states how compliance with Requirement 1 of AD/B747/386 affects EIU-replacement obligations in those older instruments, subject to part-number conditions.

• Issue and effective dates: The AD is dated 6 November 2008, signed by James Coyne, Delegate of the Civil Aviation Safety Authority. The AD "becomes effective on 18 December 2008." The compliance window specified is "Within 24 months after the effective date of this AD."

The AD text does not itself record any post-issuance amendments, revocations, or supersessions to AD/B747/386. It does, however, leave open a pathway for later revisions of the referenced service bulletins to be accepted if they receive FAA AMOC approval in relation to FAA AD 2008-13-22. The AD therefore embeds a conditional mechanism for substantive procedural changes through FAA AMOC decisions with respect to the relevant FAA AD.

No other amendment history is provided in the supplied text.

The AD text supplied does not include or reference any litigation history. There are no cases cited, no notices of legal challenge, and no mention of judicial review or dispute resolution connected to AD/B747/386 in the material provided. The only legal-style cross-references are to other airworthiness directives (FAA AD 2008-13-22; AD/B747/308; FAA AD 2004-10-05) and to service bulletins (Boeing and Rockwell Collins). The document itself is an administrative regulatory instrument and the supplied text does not record any litigation concerning it.

Accordingly, based solely on the supplied text, there is no litigation history to report. If a reader requires whether any legal challenges, judicial review proceedings, or enforcement-related disputes have since occurred, that information is not present in the AD as supplied and will need to be obtained from CASA publications, court records, or other authoritative sources outside the AD text.

The AD contains several specific technical and procedural features that can lead to compliance errors if overlooked. The following points are concrete and drawn from the AD text:

• Applicability is defined by the Boeing SB, not by an independent list. The AD applies to "Model 747-400, 747-400D and 747-400F series aeroplanes, as identified in Boeing Service Bulletin (SB) 747-31-2368, Revision 1, dated 24 July 2006." That means an aircraft owner or operator must check that Boeing SB Rev 1 to determine whether a particular airframe serial number is included. Assuming all 747-400s are affected could be incorrect.

• The AD requires replacement "of at least one of the three" EIUs, not all three. The precise phrase is "Replace at least one of the three electronic flight instrument system/engine indicating and crew alerting system (EFIS/EICAS) interface units (EIU), part number (P/N) 622-8589-104... with a new or modified EIU, P/N 622-8589-105." Replacing only one EIU meets the literal requirement, but operators must be cautious about interactions with other ADs: the AD only treats such a replacement as terminating action for prior EIU-replacement obligations if the remaining two EIUs are P/N 622-8589-104 or 622-8589-105.

• Exact part numbers and location matter. The AD specifies EIU P/N 622-8589-104 as the existing unit to be replaced and P/N 622-8589-105 as the replacement. The unit location is identified as "on the E2-6 shelf of the main equipment centre." Using the wrong P/N or installing in the wrong equipment shelf risks non-compliance.

• The conversion route via Rockwell Collins SB must follow that SB’s instructions. Note 1 makes Rockwell Collins SB EIU-7000-31-502 (21 March 2006) an additional source for modifying an EIU by adding auto restart circuitry, "which converts EIU P/N 622-8589-104 to P/N 622-8589-105." Modifying a unit in a different way, or claiming conversion without following this SB, may not yield the P/N change the AD contemplates.

• Later SB revisions are only acceptable where the FAA has approved them as AMOCs to FAA AD 2008-13-22. The AD does not accept later revisions per se. It accepts "Later revisions of the above SB(s), approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-22." Using a later SB revision lacking that FAA AMOC approval may not be acceptable for compliance with this Directive.

• Pre-effective-date work is only acceptable if it followed the earlier Boeing SB. The AD states that "Actions accomplished before the effective date of this Directive in accordance with Boeing SB 747-31-2368, dated 22 November 2005... are considered acceptable." That acceptance is tied to that earlier Boeing SB; work done before the AD effective date under another procedure might not be accepted.

• Terminating action for AD/B747/308 or FAA AD 2004-10-05 is conditional and limited. Even where replacement per Requirement 1 constitutes terminating action for the EIU-replacement requirement of the earlier ADs, all other actions required by Requirement 1 of AD/B747/308 or paragraph (d)(1) of FAA AD 2004-10-05 must still be complied with. Do not treat the terminating-action language as a blanket discharge of obligations under the older ADs.

• The AD text does not state how compliance will be evidenced or recorded. The AD requires the replacement and refers to service bulletins, but does not include a procedure for submission of compliance proof to CASA in the supplied text. Operators will need to check CASA’s AD publication or regulatory practice for required post-compliance paperwork.

• No enforcement or penalty language in the AD text. The absence of enforcement language in this AD text can mislead readers into thinking non-compliance is consequence-free. The AD is an airworthiness directive issued by CASA; failure to comply may have regulatory consequences under CASA’s broader enforcement regime, but the AD itself does not set those out.

• The AD expressly refers to FAA ADs as part of its compliance architecture. Relying on FAA documents without checking the exact AMOC approval status for later SB revisions may create compliance risk.

These gotchas are concrete, specific and drawn from the language of the Directive. Ensuring compliance requires attention to part numbers, equipment location, the correct version of service instructions, and the conditional linkages to earlier ADs and FAA AMOC approvals.

To comply with AD/B747/386 as set out in the supplied text, follow these discrete, source-prescribed steps and checks:

1. Confirm applicability via Boeing SB 747-31-2368, Revision 1, dated 24 July 2006. The AD’s applicability is expressly limited to "Model 747-400, 747-400D and 747-400F series aeroplanes, as identified in Boeing Service Bulletin (SB) 747-31-2368, Revision 1, dated 24 July 2006." Check the SB to determine whether the particular aircraft serial number is listed.

2. Schedule the work within the AD’s compliance window. The AD becomes effective 18 December 2008 and requires compliance "Within 24 months after the effective date of this AD." Plan maintenance, parts procurement and aircraft downtime so the replacement is completed within that 24-month period.

3. Use the Boeing SB Accomplishment Instructions to perform the replacement. The AD mandates replacement "in accordance with the Accomplishment Instructions of SB 747-31-2368, Revision 1." Obtain that SB Revision 1 and ensure the maintenance task follows the step-by-step Accomplishment Instructions therein.

4. Replace at least one EIU P/N 622-8589-104 located on the E2-6 shelf of the main equipment centre with a new or modified EIU P/N 622-8589-105. The AD’s Requirement block specifies both old and new part numbers and the precise location to be addressed.

5. If using modification rather than factory replacement, follow Rockwell Collins SB EIU-7000-31-502. Note 1 identifies Rockwell Collins SB EIU-7000-31-502, dated 21 March 2006, as an "additional source of service information for modifying an EIU by adding auto restart circuitry, which converts EIU P/N 622-8589-104 to P/N 622-8589-105." If choosing the modification pathway, perform the modification strictly in accordance with that Rockwell Collins SB so that the unit is converted to the P/N 622-8589-105 configuration contemplated by the AD.

6. Verify part numbers after work. After installation or modification, confirm the part number on the unit is P/N 622-8589-105. The AD conditions terminating action in relation to earlier ADs on the part numbers of the remaining EIUs, so accurate identification and documentation of the part numbers of all three EIUs is essential.

7. Confirm whether replacement constitutes terminating action for earlier ADs. If the replacement has been carried out per Requirement 1, check whether the two remaining EIUs are P/N 622-8589-104 or P/N 622-8589-105. If they are, the AD states that the replacement "constitutes terminating action for the EIU replacement (Requirement 3 of AD/B747/308 or paragraph (d)(1) of FAA AD 2004-10-05)." However the AD also states that "All other actions required by Requirement 1 of AD/B747/308 or paragraph (d)(1) of AD 2004-10-05 must be complied with." So document the part numbers and preserve compliance with any remaining requirements of those prior ADs.

8. For work already done before the AD’s effective date, check the earlier Boeing SB provenance. The AD accepts as compliant "Actions accomplished before the effective date of this Directive in accordance with Boeing SB 747-31-2368, dated 22 November 2005." If the earlier work followed that 22 November 2005 Boeing SB, treat it as compliant for the corresponding requirements of this AD; otherwise, document the differences and assess whether further work is needed.

9. For later service bulletin revisions, confirm FAA AMOC approval. The AD accepts "Later revisions of the above SB(s), approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2008-13-22" as acceptable for compliance. If you plan to rely on a later revision of Boeing SB 747-31-2368 or Rockwell Collins EIU-7000-31-502, obtain written FAA AMOC approval showing that the later revision is an AMOC to FAA AD 2008-13-22 and document that approval as part of your compliance records.

10. Maintain compliance records consistent with organisational and regulatory practice. The AD text does not state how CASA expects compliance to be evidenced. Therefore, in addition to recording the SB revision used, the part numbers before and after the work, and any FAA AMOC approvals relied on, retain the work order, sign-off by authorised maintenance personnel, and any certification records customary in your operating and regulatory environment. That documentation will be necessary if CASA or another authority seeks evidence of compliance.

11. If uncertain about the interaction with AD/B747/308 or FAA AD 2004-10-05, consult the relevant AD texts. The AD references these earlier ADs for the purposes of terminating certain EIU-replacement obligations and preserving other obligations; read those ADs to confirm what "All other actions required" entails and to ensure you have satisfied those remaining obligations.

12. Do not rely on informal or undocumented modifications. The AD sets precise part-number and SB-based pathways to compliance. Only units modified according to the Rockwell Collins SB that effect the conversion to P/N 622-8589-105, or factory P/N 622-8589-105 units, are referenced by the AD.

Following these steps aligns with the exact language of the Directive and the service documents it references. The AD does not specify enforcement actions, payment responsibility or post-completion submission processes in the supplied text, so preserve thorough documentation in case CASA or another regulator requires evidence of compliance.