AD/F2000/18 - Segregation of ADC/IRS Wiring

The Directive is organised around three main technical and procedural concepts: wiring segregation, functional testing frequency, and dispatch conditions as enforced through the MEL.

Wiring segregation: The core technical deficiency identified is that "all IRS primary inputs are wired to the same General Purpose (GP) Bus" (Background). The Directive mandates a hardware/installation change identified as modification M2758 specifically to IRS 2. This is targeted at re‑segregating inputs so that a single air data or ADS error cannot propagate identically to both pilot and co‑pilot displays. The required accomplishment instructions are those contained in Service Bulletin SB‑F2000EX‑89 or later revisions approved by EASA (Requirement 1). The Directive therefore blends a field modification with a requirement to follow an approved technical procedure.

Functional testing frequency and method: To preserve segregation over time, the Directive makes a permanent change to the maintenance regime. Operators must insert Revision 2 of Chapter 5.40 into the Maintenance Manual and introduce MP 34‑209, "test of general purpose bus IRS entry", at 5 000 flight hour intervals (Requirement 2). Mechanically, that creates a recurring testing obligation tied to flight hours, rather than a one‑off post‑modification check alone.

Dispatch conditions via MEL: The Directive mandates amendment of the applicable MEL to reflect dispatch conditions for "one IRS failure" as contained in Dassault Aviation Master MMEL temporary change TC 4 (Requirement 3). That links technical changes to operational permissibility: the MEL changes will redefine how an IRS failure affects dispatchability once the wiring change has been implemented. The Directive notes that these dispatch conditions are modified after implementation of the wiring change (Background).

Regulatory cross‑references and authorisations: The Directive refers to and requires work performed "in accordance with the accomplishment instructions of Service Bulletin SB‑F2000EX‑89 or later revisions approved by the European Aviation Safety Agency (EASA)" (Requirement 1), and it refers to EASA AD 2006‑0157. The document is issued under the authority of the Civil Aviation Safety Authority, signed by the Delegate, James Coyne (22 June 2006), and becomes effective 3 August 2006 (Compliance). Thus, the technical work must follow manufacturer service material but only to the extent that revisions are approved by EASA, not solely by the manufacturer.

The Directive names specific equipment and a narrow fleet subset. Applicability is limited to "Falcon 2000EX EASy serial numbers (S/N) 06, 28 and subsequent" (Applicability). That is the explicit locus of regulatory effect. Operators, owners, and maintenance organisations who operate or service those serial numbers are the parties required to act.

Primary economic actors required to pay and act are aircraft operators and their maintenance providers. The Directive's actions are installation and maintenance items: incorporation of wiring modification M2758 (Requirement 1), amendment of the operator's Maintenance Manual (Requirement 2), and amendment of the operator's MEL (Requirement 3). Those are tasks normally carried out by the operator or by contracted approved maintenance organisations and their costs,parts, labour, engineering hours, downtime and any modifications to maintenance scheduling,fall on the operator. The Service Bulletin SB‑F2000EX‑89 is the specified procedural document but the Directive conditions its use to the version "or later revisions approved by the European Aviation Safety Agency (EASA)" (Requirement 1), so EASA plays a role in approving the implementation details.

Who decides: the Directive itself is issued by the Civil Aviation Safety Authority through its Delegate, and it requires operators to use EASA‑approved revisions of the service bulletin where applicable. Dassault Aviation is implicated as the source of the Maintenance Manual revision and of the Master MMEL temporary change TC 4, since the Directive requires insertion of Revision 2 of Chapter 5.40 of the Falcon 2000EX EASy Maintenance Manual and adoption of the Master MMEL TC 4 dispatch conditions (Requirements 2 and 3). The source shows a chain: manufacturer issues SB and MMEL TC, EASA approves SB revisions, CASA issues the AD requiring operators to implement the manufacturer instructions.

Operational consequences for different actors: Maintenance organisations must perform wiring modifications and testing per the SB and the Maintenance Manual insertion MP 34‑209 at 5 000 flight hour intervals. Flight operations departments will need to amend MEL entries and the associated dispatch practises for "one IRS failure", following Dassault Aviation Master MMEL temporary change TC 4 (Requirement 3). Scheduling departments must fit the wiring mod and the initial tests into aircraft availability within the three‑month compliance window (Compliance), which creates short‑term resource allocation and potential downtime costs. The Directive explicitly affects only the listed serial numbers; aircraft outside that serial range are not covered by this text.

Duties are explicit and discrete. The Directive sets three mandatory duties for operators of applicable aircraft.

Duty 1, installation and test: For F2000EX EASy aeroplanes in the applicability range that do not have modification M2758 incorporated, operators must incorporate IRS 2 wiring modification M2758 and test the GP bus IRS entry in accordance with the accomplishment instructions of Service Bulletin SB‑F2000EX‑89 or later EASA‑approved revisions (Requirement 1). The duty is both an installation duty and a verification duty to follow the specified service bulletin instructions.

Duty 2, maintenance manual amendment and recurring testing: Operators must amend the Falcon 2000EX EASy Maintenance Manual by inserting Revision 2 of Chapter 5.40 to introduce MP 34‑209, "test of general purpose bus IRS entry", at 5 000 flight hour intervals (Requirement 2). This creates an ongoing, scheduled maintenance obligation tied to flight hours.

Duty 3, MEL amendment for dispatch: Operators must amend the applicable MEL to reflect the dispatch conditions for "one IRS failure" as contained in Dassault Aviation Master MMEL temporary change TC 4 (Requirement 3). This duty requires change to operational authorisations and potentially the conditions under which an aircraft may be dispatched with certain faults.

Timing duty: All three duties must be executed "at the earliest opportunity but no later than three months after the effective date of this Directive" (Compliance). The effective date is given as 3 August 2006, so the deadlines are strict within the three‑month period following that date.

Rights and procedural limits: The Directive explicitly permits the use of later revisions of Service Bulletin SB‑F2000EX‑89 only if those revisions are approved by EASA (Requirement 1). That constrains operators to EASA‑approved procedures rather than unconditional reliance on manufacturer revisions. The Directive does not provide alternative compliance methods within its text. The source does not specify a process for applying for an alternative method of compliance or a relief mechanism. It also does not state any administrative appeals process in the Directive text. Rights to deviate from the specified measures, or to defer compliance, are not contained in the document.

Who decides technical compliance: overall technical compliance is judged by adherence to the accomplishment instructions of the service bulletin and to the insertion of the specified Maintenance Manual revision and MEL change. The EASA approval requirement means an external aviation safety authority will be the reference for whether a later revision is acceptable. The Directive is silent on how CASA will audit or verify compliance, and it does not enumerate paperwork or record‑keeping procedures beyond the maintenance manual and MEL changes themselves.

The text of the Directive provides the prescriptive measures and dates but does not set out specific penalties, fines or enforcement procedures. It states that "This Airworthiness Directive becomes effective on 3 August 2006" and sets the compliance interval for the three specified requirements as "at the earliest opportunity but no later than three months after the effective date of this Directive" (Compliance). The document is issued under the authority of the Civil Aviation Safety Authority, with the signature block showing "James Coyne, Delegate of the Civil Aviation Safety Authority" and the date 22 June 2006.

What the source shows and does not show: the Directive itself mandates actions but the AD text supplied does not include an enforcement clause, a civil or criminal penalty schedule, administrative sanction modes, or procedures for post‑issue surveillance and rectification. The directive also does not specify whether non‑compliant aircraft will be grounded or subject to specific remedial action by the regulator. The AD does, however, link required actions to documented technical material: incorporation of modification M2758 per SB‑F2000EX‑89 (or later EASA‑approved revisions), insertion of a Maintenance Manual revision, and MEL amendment per the Master MMEL temporary change TC 4 (Requirements 1-3). These are discrete technical obligations whose completion will be verifiable in maintenance records and MEL entries.

Implication for operators: In practice, compliance with an AD is a regulatory obligation; the issuing authority is named. The Directive leaves the precise enforcement mechanisms and remedies unspecified in the text provided. Where a regulator issues an AD, typical enforcement steps may include audits, airworthiness inspections and administrative action, but those mechanisms are not described in the source document itself. The only enforcement‑adjacent content in this AD is the effectiveness date and the three‑month compliance window, which create a time‑bounded obligation.

The AD, as drafted, cross‑references and relies on non‑statutory regulatory and manufacturer instruments rather than setting out interactions with other legislation in its text. The Directive explicitly refers to EASA AD 2006‑0157 and requires that the service bulletin SB‑F2000EX‑89 be followed "or later revisions approved by the European Aviation Safety Agency (EASA)" (Requirement 1). It also requires amendment of the operator's MEL in accordance with Dassault Aviation Master MMEL temporary change TC 4 (Requirement 3). The Maintenance Manual insertion is specified as Revision 2 of Chapter 5.40, which introduces MP 34‑209 at 5 000 flight hour intervals (Requirement 2).

The instrument therefore sits in a compliance chain linking manufacturer documentation, EASA approvals and the national AD. The Service Bulletin procedures required by the AD are acceptable only if EASA has approved any later revisions. That creates an operational dependency: implementation details depend on EASA approval status of SB revisions, while the AD itself is the national requirement to implement the approved procedures. The AD points operators to the manufacturer master MMEL temporary change TC 4 for dispatch condition wording, so it coordinates operational permissibility with manufacturer MMEL material.

The Directive does not use the text to displace or amend the Maintenance Manual or MEL beyond requiring the insertion of a specific Revision and the MEL amendment. The Maintenance Manual and MEL remain the documents of record for maintenance and dispatch authorisation. The AD does not explicitly state how conflicts between existing MEL entries and the required MMEL TC 4 text are to be reconciled; it simply instructs operators to "Amend the applicable Minimum Equipment List (MEL) to reflect the dispatch conditions ... contained in the Dassault Aviation Master Minimum Equipment List temporary change TC 4" (Requirement 3). That implies that the MMEL TC 4 wording becomes the required MEL entry for affected types under this AD.

No other statutes or regulations are mentioned in the supplied text. The AD does not set out interactions with civil aviation legislation, air transport safety law, or administrative law procedures in the text provided. The document does not provide a process for alternative compliance, exemptions, or appeals within its own text, nor does it reference domestic legislative instruments. The only institutional interactions explicitly shown are between CASA as issuer, Dassault Aviation as manufacturer/document owner, and EASA as approver of service bulletin revisions.

The AD text supplies a limited amendment history. It contains the effective date and issuance metadata. The Directive was signed "22 June 2006" by the Delegate of the Civil Aviation Safety Authority, James Coyne, and it states "This Airworthiness Directive becomes effective on 3 August 2006" (Compliance and signature block). The compliance timing clause requires that the three listed requirements be completed "at the earliest opportunity but no later than three months after the effective date of this Directive" (Compliance).

The AD notes that EASA AD 2006‑0157 is referred to in the Note section, indicating that a parallel or corresponding EASA directive exists and that the service bulletin approvals referenced in Requirement 1 should be EASA‑approved versions. Requirement 1 allows use of "later revisions approved by the European Aviation Safety Agency (EASA)", which implies an amendment pathway for future changes to the service bulletin, but only with EASA approval.

The Maintenance Manual amendment demanded is to insert "Revision 2 of Chapter 5.40" into the Falcon 2000EX EASy Maintenance Manual, thereby effecting a change in the maintenance programme. The MEL change required is to "reflect the dispatch conditions ... contained in the Dassault Aviation Master Minimum Equipment List temporary change TC 4", meaning the AD effectively incorporates that temporary MMEL change into the operator's MEL through this directive.

The source does not include any later amendments to AD/F2000/18 itself. The only modification pathway mentioned within the text is the acceptance of later revisions of the service bulletin if EASA approves them, and the AD’s own effective date and three‑month compliance window. No revision numbers or superseding ADs are presented in the supplied text, and the AD does not list any prior ADs it replaces. The only cross‑reference in the text is to EASA AD 2006‑0157.

The source contains no litigation history. The AD text does not reference any judicial or administrative appeals, nor does it cite cases, precedent, or dispute resolution events. It does not record any challenges to the directive, nor any litigation outcomes related to the technical deficiency or to the AD's issuance. The document is purely an administrative safety directive with issuance metadata and technical requirements.

Practical consequence for researchers: because the supplied text does not include any references to litigation, you cannot, from this source alone, identify any judicial review, enforcement action, or contested matter arising from AD/F2000/18. Any search for litigation or appeals would need to use external materials beyond the text provided. The AD does indicate institutional actors (CASA as issuer, EASA as approver, Dassault Aviation as manufacturer), which provides likely parties that could be involved in any litigation, but the AD text itself contains no account of subsequent legal challenges, enforcement proceedings, or court decisions.

For compliance documentation and potential disputes, the recordable items in this AD are the completion of modification M2758 and the accompanying test per SB‑F2000EX‑89, insertion of Revision 2 of Chapter 5.40 into the Maintenance Manual, and MEL amendments per Dassault Master MMEL TC 4. Those items would be the focal points in any enforcement or litigation scenario, but the AD text does not describe dispute procedures or adjudicative outcomes.

The Directive includes a number of concrete pitfalls and operational details that create risk or potential for error if not carefully managed.

Applicability is narrow and precise: the AD applies only to "Falcon 2000EX EASy serial numbers (S/N) 06, 28 and subsequent" (Applicability). Operators must verify serial number applicability carefully. Aircraft outside that serial range are not included in this text.

Pre‑existing modification M2758 matters: Requirement 1 is conditional. It applies "for F2000EX EASy aeroplanes in the applicability range and without modification M2758". That means aircraft that have already incorporated M2758 will not need the same installation work, but must still comply with other requirements. Operators must audit configuration status to determine whether they already have M2758 or whether incorporation is required.

Service bulletin approval constraint: The wiring modification and its test must be performed "in accordance with the accomplishment instructions of Service Bulletin SB‑F2000EX‑89 or later revisions approved by the European Aviation Safety Agency (EASA)" (Requirement 1). Using a later revision of the service bulletin requires EASA approval. Implementing a manufacturer revision that lacks EASA approval would not meet the AD’s stated standard.

Maintenance manual insertion specificity: Requirement 2 requires insertion of "Revision 2 of Chapter 5.40" to introduce MP 34‑209 at 5 000 flight hour intervals. Operators must ensure they insert the correct revision, and that their maintenance programme scheduling reflects the 5 000 FH interval. Failure to insert the specified revision, or to track the 5 000 FH interval, would leave the operator non‑compliant with the AD.

MEL wording: Requirement 3 directs adoption of dispatch conditions "contained in the Dassault Aviation Master Minimum Equipment List temporary change TC 4". Operators should ensure the MEL amendment precisely reflects TC 4 wording. Ambiguity or divergence in wording could create operational and safety interpretation issues on dispatch.

Timing pressure: The compliance window is tight: "at the earliest opportunity but no later than three months after the effective date of this Directive" with an effective date of 3 August 2006 (Compliance). Operators must schedule modification, testing, manual updates and MEL amendment within that timeframe, which may require rapid allocation of maintenance slots and certified personnel.

Operational effect on dispatch: The Background paragraph notes that dispatch conditions under the MMEL in case of an IRS2 failure are modified after implementation of the wiring change. That means the operational rules for flying with one IRS inoperative will change once the wiring mod is in place. Operators must coordinate pilot training and dispatch controllers to apply the new MEL entries correctly.

Testing and recurring burden: The new MP 34‑209 creates a recurring maintenance obligation at every 5 000 flight hours. Operators must update maintenance planning and record‑keeping to ensure that this periodic test is performed and documented.

Scope of the fix: The Directive addresses wiring segregation and GP bus IRS entry testing. The Background makes clear the trigger was a flight test after an air data probe failure that produced identical wrong parameters on both PDUs. The AD does not purport to address other potential ADS/IRS failure modes outside the wiring segregation issue, so operators should not assume all ADS/IRS risks are covered by this single AD.

EASA cross‑reference: The AD refers to EASA AD 2006‑0157. Operators should read and reconcile the EASA text and their local AD to ensure consistent implementation and to confirm any differences, but the AD does not provide the EASA AD text itself.

Compliance requires a sequence of actions tied to documentation and physical work, to be completed within the three‑month compliance window from the AD effective date of 3 August 2006.

1. Determine applicability and configuration status. Confirm whether each Falcon 2000EX EASy in your fleet is within the serial number applicability: S/N 06, 28 and subsequent. For each applicable aeroplane, confirm whether modification M2758 is already incorporated. Requirement 1 applies only to those without M2758.

2. If M2758 is not present, incorporate the IRS 2 wiring modification M2758. Carry out the wiring change in strict accordance with the accomplishment instructions of Service Bulletin SB‑F2000EX‑89, or a later revision if that later revision has been approved by EASA, as required by Requirement 1. Ensure that the maintenance organisation performing the work holds the necessary approvals for electrical wiring changes on the Falcon 2000EX EASy.

3. After incorporation of M2758, perform the mandated test of the GP bus IRS entry in accordance with the service bulletin accomplishment instructions, as required by Requirement 1. Record test results in the aircraft maintenance records in the form and manner normally used by the operator for AD compliance evidence.

4. Amend the Falcon 2000EX EASy Maintenance Manual. Insert Revision 2 of Chapter 5.40 to introduce MP 34‑209, "test of general purpose bus IRS entry", scheduled at 5 000 flight hour intervals, as required by Requirement 2. Update maintenance programme tracking systems to schedule the recurring MP 34‑209 at 5 000 FH intervals and allocate resources for periodic execution.

5. Amend the operator's MEL. Update the MEL to reflect the dispatch conditions for "one IRS failure" as contained in Dassault Aviation Master MMEL temporary change TC 4, as required by Requirement 3. Ensure the MEL amendment language matches the MMEL TC 4 wording and train operations staff and dispatch authorities on the revised dispatch conditions.

6. Verify conformity with EASA approvals. When using any later revision of SB‑F2000EX‑89, ensure the revision is EASA‑approved before relying on it for compliance. Keep copies of EASA approval documentation alongside the maintenance actions and records.

7. Record keeping and evidence. Maintain maintenance records showing incorporation of M2758, the GP bus IRS entry test results, the Maintenance Manual insertion (Revision 2 of Chapter 5.40), and the MEL amendment reflecting MMEL TC 4. These records constitute evidence of compliance with the AD.

8. Scheduling and risk management. Because the AD requires completion "at the earliest opportunity but no later than three months after the effective date" (Compliance), prioritise scheduling of modification and testing to avoid non‑compliance. Coordinate with maintenance providers, parts suppliers and EASA approval tracking where relevant.

9. Cross‑reference EASA AD 2006‑0157. Review EASA AD 2006‑0157 to reconcile any additional details or instructions that may impact how the SB or MMEL changes are to be implemented, noting that the AD itself refers to EASA AD 2006‑0157.

10. Operational rollout. Once physical modifications and manual/MEL changes are complete, disseminate to flight crew and operations personnel the implications of the MEL change for dispatch with one IRS failure, and update any relevant checklists and procedures to reflect the new maintenance and dispatch regime.

Completing these steps within the AD’s three‑month window and keeping clear documentary evidence will be the practical path to satisfying the requirements set out in AD/F2000/18.