AD/F100/79 - Passenger Service Unit

The Directive rests on a narrow set of technical facts and prescriptive steps. Its key concepts are: applicability to a defined set of aircraft and PSU part numbers (Applicability); a mandated inspection procedure tied to a specific Fokker Service Bulletin (Requirement 1); a mandatory rectification pathway using the same Service Bulletin if discrepancies are found (Requirement 2); explicit compliance timing (Compliance); and a description of the defect and its safety consequence (Background).

Applicability is precise: the AD applies to "F28 Mark 0100 aeroplanes equipped with Honeywell International (Grimes Aerospace) Passenger Service Units (PSU) part number (P/N) 10-1178-XX series or 10-1571-XX series, unless modified per Fokker Service Bulletin SBF100-25-070 dated 15 March 1995" (Applicability). That phrasing creates an exclusion for aircraft previously modified under SBF100-25-070; in practical terms, aircraft that received that modification are not within the AD’s mandatory scope as written.

The inspection and rectification steps are not freeform. The AD instructs operators to follow Section 3 - Accomplishment Instructions - of Fokker Service Bulletin SBF100-25-108 dated 31 March 2006, or a later EASA approved revision (Requirement 1 and Requirement 2). The AD thereby imports a private technical document by reference and ties compliance to the versioning status as approved by EASA.

The safety premise is technical and causal. The Background records that an operator discovered PSU electrical connectors did not lock properly. Investigation attributed the defect to tolerance in thickness of the gaskets inside the PSU connectors; that tolerance allowed incomplete locking, which can cause connector overheating, electrical arcing, failure of PSU panels, and smoke. The manufacturer narrowed gasket thickness tolerances to eliminate the cause (Background). The AD is therefore corrective and targeted: inspect interface connectors and replace affected J1 and J2 interface connector gaskets to prevent overheating and arcing.

Timing and immediacy are explicit. The inspection must be accomplished within 36 months after the effective date; rectification must be done before further flight if discrepancies are found (Compliance). This structure creates a window for non-urgent scheduling of inspections, but it also makes any defect discovered immediately actionable because rectification is required prior to continued flight.

The Directive also records the regulatory provenance: it refers to CAA-NL AD NL-2006-008 (EASA Approval 2006-0193) and limits acceptable service bulletin editions to those approved by EASA. The AD therefore situates itself in a network of national and European regulatory instruments and service-provider instructions.

The AD directly binds operators and maintainers of Fokker F100 (F28 Mark 0100) aeroplanes that are fitted with the specified Honeywell/Grimes PSU part numbers 10-1178-XX series or 10-1571-XX series (Applicability). This includes any operator, owner or maintenance organisation responsible for the airworthiness of such aircraft, because the AD prescribes mandatory inspections and rectifications that must be carried out on the aircraft. Aircraft previously modified in accordance with Fokker Service Bulletin SBF100-25-070 dated 15 March 1995 are expressly excluded from applicability, so those aircraft and their operators are not required by this AD to carry out the actions described (Applicability).

Maintenance organisations and AMOs that perform the inspection and rectification work are affected because the AD requires adherence to Section 3 of Fokker SBF100-25-108 dated 31 March 2006, or a later EASA approved revision (Requirement 1 and Requirement 2). The AD thereby compels the use of a particular manufacturer-prescribed procedure by reference. Supply-chain actors are also implicated: the remedial action includes replacing PSU Panel J1 and J2 interface connector gaskets where necessary; operators will therefore need access to replacement gaskets that conform to whatever specification the Service Bulletin or manufacturer provides.

Regulators and certification bodies are implicated indirectly: the AD references CAA-NL AD NL-2006-008 and EASA approval 2006-0193 and prescribes only EASA approved later revisions of the Service Bulletin. This ties the Australian directive to EASA-approved documentation and to the Netherlands CAA’s findings (Note; Background).

Passengers are not addressees of the directive, but the safety premise concerns risks that would manifest in passenger cabins (smoke from PSU panels). The operational outcome,inspection and repair,aims to reduce the likelihood of such events.

Who bears the cost: the AD assigns the physical work and scheduling to operators and their sanctioned maintenance providers. The AD specifies neither funding nor compensation mechanisms. The AD sets the window for inspection at up to 36 months after the effective date and requires rectification before further flight, creating an operational constraint for operators who find defective connectors; if discrepancies are found, the aircraft cannot continue in service until the rectification specified by the Service Bulletin is completed (Compliance). The AD does not indicate alternative compliance methods, nor does it list any exceptions or waivers; it does allow use of a later EASA-approved revision of the referenced Service Bulletin.

Finally, the AD’s practical scope is limited by the exact P/N ranges given and the stated modification exception. That means only a subset of F100 fleet operators will be affected, while other F100 variants or aircraft fitted with different PSUs are outside the AD’s prescription.

Duties imposed by the AD are concrete and procedural. Operators and maintenance organisations must:

• Identify applicability: determine whether the aircraft is an F28 Mark 0100 fitted with PSU P/N 10-1178-XX series or 10-1571-XX series, and verify whether the aircraft has been modified per Fokker Service Bulletin SBF100-25-070 dated 15 March 1995 (Applicability). If modified per that SB, the AD does not apply to that aircraft.

• Inspect: carry out inspection of the affected PSU panel interface connectors in accordance with Section 3 - Accomplishment Instructions - of Fokker SBF100-25-108 dated 31 March 2006, or a later EASA approved revision (Requirement 1). This inspection must be completed within 36 months after the effective date of the AD (Compliance).

• Rectify: if the inspection reveals any discrepancies, rectify the discrepancy in accordance with the same Section 3 instructions of SBF100-25-108 or later EASA approved revision (Requirement 2). Rectification must be completed before further flight (Compliance).

• Replace gaskets where necessary: the AD text identifies replacement of the affected PSU Panel J1 and J2 interface connector gaskets as the corrective action where the unsafe condition has been identified (paragraph starting "Since an unsafe condition has been identified...").

Rights and limits under the AD, as expressed within the source, are narrower. The AD explicitly allows compliance using Section 3 of Fokker SBF100-25-108 dated 31 March 2006, or a later EASA approved revision, which gives operators the right to use a later EASA-approved revision of the Service Bulletin. The AD does not specify alternative methods of compliance or exemptions; it does not set out an appeal or variation mechanism within the text provided.

Timing rights and constraints are significant. Operators have up to 36 months to schedule the inspection (Compliance). That creates flexibility in planning maintenance but does not permit continued flight if a discrepancy is found: rectification is required "before further flight" (Compliance). That operational constraint affects scheduling and dispatch decisions. The AD does not specify acceptable means of record-keeping or reporting back to the regulator within the provided text; such administrative expectations, if any, are not stated.

The AD ties permissible procedures to EASA approval of Service Bulletin revisions. That places some decision latitude in the hands of EASA with respect to what revised instructions can be used for compliance in Australia, as the AD allows "later EASA approved revision[s]" of SBF100-25-108. Within the text provided the Australian authority has adopted an EASA-linked compliance standard.

In summary, the primary duties are identification, inspection per the prescribed SB, mandatory rectification if problems are found, and replacement of specific gaskets where necessary. The principal rights are the ability to use later EASA-approved revisions of the referenced Service Bulletin and a 36-month window to carry out the initial inspection. The AD does not enumerate alternative compliance routes or procedural appeals in the text supplied.

The AD itself does not, within the supplied text, state statutory penalties, fines, or enforcement procedures beyond the compliance requirements and effective date. The content sets out mandatory technical and timing obligations,inspection within 36 months, rectification before further flight if discrepancies are found,but it does not include a penalty schedule or specify enforcement actions for non-compliance in the text provided (Compliance).

Enforcement implications arise from the AD’s formal status and operational constraints embedded in its wording. The AD becomes effective on 31 August 2006 (Compliance), and by requiring rectification before further flight after a deficient inspection finding, it establishes a ground on which an aircraft could be considered unairworthy or non-compliant with the AD until rectification is completed. The AD’s requirement that rectification occur before further flight creates an immediate operational enforcement mechanism: discovery of a discrepancy effectively grounds the aircraft until the specified corrective action is taken. This is explicit in the Compliance text: "For Requirement 2 - Before further flight after the Requirement 1 inspection."

The AD references CAA-NL AD NL-2006-008 and EASA Approval 2006-0193, which indicates a cross-jurisdictional regulatory context and suggests that EASA-approved methods are the recognised path for compliance. However, the AD document as provided does not spell out administrative reporting obligations, certificate suspension procedures, or civil or criminal penalties for failing to comply. Absent such text within the AD, readers must treat enforcement details as not specified here.

Practical enforcement will typically be conducted by the issuing civil aviation authority through its usual oversight mechanisms; the AD’s signature block shows it was issued by James Coyne, Delegate of the Civil Aviation Safety Authority, on 21 July 2006. The AD’s prescriptive actions and timelines are therefore binding expectations coming from that authority. The AD’s requirement that work be completed in accordance with an EASA-approved service bulletin gives the regulator a concrete standard against which to assess the adequacy of maintenance actions if compliance is audited.

In short, the AD establishes mandatory technical requirements and timing constraints and creates a de facto operational enforcement point (no further flight until rectification where discrepancies are found). It does not, within the text supplied, provide an explicit penalty regime or an enforcement procedure beyond these compliance directives.

Within the text provided, the AD explicitly connects to international and manufacturer-issued technical material rather than domestic statute or unrelated regulations. The AD references Netherlands CAA AD NL-2006-008 and EASA Approval 2006-0193 (Note), and it conditions acceptable compliance documentation on "later EASA approved revision[s]" of Fokker Service Bulletin SBF100-25-108 dated 31 March 2006 (Requirement 1 and Requirement 2). This shows the AD is drafted to be consistent with, and to rely upon, EASA-approved service instructions. Consequently, the AD interacts with certification or maintenance directions issued by EASA and the Netherlands CAA by incorporating EASA-approved revisions as the allowable pathway for compliance.

The AD excludes aircraft modified under Fokker Service Bulletin SBF100-25-070 dated 15 March 1995 from applicability (Applicability). This creates an interaction with prior service-modification actions: where an aircraft has already been modified under that SB, the AD does not require the inspection and rectification steps. Thus prior conformity with an earlier Fokker SB can remove the AD’s applicability for a given aircraft.

The AD does not, in the supplied text, reference or amend any domestic legislative instrument, Civil Aviation Safety Regulations, airworthiness standards, or other domestic legal instruments by citation. It also does not describe how compliance with the AD affects certification documents, maintenance release procedures, or continuing airworthiness approvals, beyond the practical implication that rectification is required prior to further flight if discrepancies are discovered. Any interactions with domestic certification paperwork (for example, logbook entries or conformity documentation) are not specified in the AD text provided.

By specifying adherence to an EASA-approved Service Bulletin, the AD imports that document’s technical requirements into its compliance regime. Any legal obligations, limitations or requirements embedded within the referenced Service Bulletin that are EASA-approved thereby become relevant to fulfilling the AD. The AD allows later EASA-approved revisions of SBF100-25-108; this creates an ongoing interaction where subsequent EASA approvals of SB revisions will be recognised as compliant pathways under the AD.

No cross-reference is made in the supplied text to enforcement statutes, penalty provisions, or appeal rights, so any interaction with statutory enforcement mechanisms is not explicitly set out here. The AD’s connection to CAA-NL AD NL-2006-008 and EASA approvals places it within a wider international regulatory ecosystem for continued airworthiness, but the exact administrative interactions with domestic law and regulatory procedures are not articulated within the document text supplied.

The AD document identifies dates and referenced service bulletins that establish its amendment provenance. The directive is dated 21 July 2006, and it states that the AD becomes effective on 31 August 2006 (Compliance). It carries the identifier AD/F100/79 (9/2006) and repeats the AD number in multiple places.

The AD requires actions in accordance with Fokker Service Bulletin SBF100-25-108 dated 31 March 2006, or later EASA approved revision (Requirement 1 and Requirement 2). Therefore, the March 2006 Service Bulletin is the operative technical reference for the AD at the time of issue. The text also references an earlier Fokker Service Bulletin SBF100-25-070 dated 15 March 1995 as a basis for exemption from applicability where that prior modification has been applied to an aircraft (Applicability).

The AD itself does not contain an internal amendment log or history of prior versions. It does not list superseded ADs or prior Australian ADs that it replaces. It does, however, explicitly note that CAA-NL AD NL-2006-008 (EASA Approval 2006-0193) refers, which indicates that the Netherlands CAA issued a related AD and that EASA approval is documented as 2006-0193 (Note; Background).

Because the AD permits the use of "later EASA approved revision[s]" of the referenced Service Bulletin, its compliance regime is open to amendment in practice by subsequent EASA approvals of SB revisions. Those future SB revisions, once EASA approved, are expressly allowed by this AD as acceptable compliance documentation. The AD text does not itself list any later revisions or amendments beyond the March 2006 SB, so the AD’s amendment history as recorded in the document is limited to: the March 2006 Service Bulletin reference, the March 1995 Service Bulletin exemption, the AD’s issue date of 21 July 2006, and effective date of 31 August 2006.

No further amendments to the AD are recorded in the supplied text. If subsequent amendments, corrigenda or replacement ADs exist, they are not contained in this document and nothing in the provided text asserts their existence.

The AD text supplied does not reference any litigation, legal challenges, or case law arising from this Directive. There are no reported disputes, appeals, or judicial review matters referenced in the document. The AD makes no mention of court decisions, administrative appeals, or legal proceedings concerning its issuance, scope, or compliance requirements.

The only cross-references are regulatory and technical: CAA-NL AD NL-2006-008 and EASA Approval 2006-0193, and the Fokker Service Bulletins SBF100-25-108 (31 March 2006) and SBF100-25-070 (15 March 1995). There is no mention in the AD of enforcement actions that resulted in litigation, nor of contested interpretations of the AD’s requirements.

Given the absence of litigation history in the text, readers should treat the AD as having no recorded litigation outcomes within the supplied document. Any actual litigation arising from this AD, if it exists, is not recorded here and therefore cannot be described based on the provided material.

The AD contains several technical and procedural specifics that may create operational traps if misunderstood.

1. Narrow applicability language: The AD covers only F28 Mark 0100 aeroplanes fitted with PSU P/N 10-1178-XX or 10-1571-XX series, unless modified per Fokker SBF100-25-070 dated 15 March 1995 (Applicability). Operators must verify both the aircraft model and the exact PSU part number series, and confirm whether SBF100-25-070 modification was applied. Failure to properly verify applicability may result in unnecessary inspections or missed obligations.

2. Reference-by-version and approval caveat: The AD mandates inspection "in accordance with Section 3 - Accomplishment Instructions of Fokker Service Bulletin SBF100-25-108 dated 31 March 2006 or later EASA approved revision" (Requirement 1). Compliance requires use of the March 2006 SB or a later EASA-approved revision. Using an unapproved revision or a manufacturer guidance that is not EASA approved would not meet the AD’s wording. Operators must ensure the SB revision used carries EASA approval.

3. Timing window paired with an immediate operational constraint: The inspection can be deferred up to 36 months after the effective date of the AD (Compliance). However, if the inspection reveals discrepancies, rectification is required before further flight (Compliance). That means an operator may schedule the inspection at a convenient time within 36 months, but discovery of a defect at inspection will ground the aircraft until rectification is complete. The AD therefore combines planning flexibility with an immediate grounding risk.

4. Specific gaskets and interface locations: The AD singles out PSU Panel J1 and J2 interface connector gaskets for replacement where necessary (paragraph on unsafe condition). Maintenance teams must be sure to identify the correct connectors and gaskets named in the AD and in the Service Bulletin. Mistaking gasket location or part numbers could lead to ineffective repairs.

5. Manufacturer fix and implications for parts procurement: The Background notes that the manufacturer has narrowed gasket thickness tolerances to correct the problem. Operators must obtain the properly specified replacement gaskets that conform to whatever specification the SB and manufacturer require. The AD does not supply parts or indicate supply channels; procurement of the correct parts is an operator responsibility.

6. Cross-jurisdictional references: The AD refers to CAA-NL AD NL-2006-008 and EASA Approval 2006-0193 (Note). That cross-reference means operators should check those documents for further context and for EASA-approved SB revisions. Assuming the AD stands alone could miss additional technical details or related regulatory actions referenced by the CAA-NL or EASA materials.

7. No procedural administrative detail in AD: The AD does not specify record-keeping, reporting to the regulator, or how to document compliance beyond following the SB. Operators must rely on standard maintenance practices and any regulator guidance outside this AD for audit trails; the AD text itself does not list administrative steps.

8. The AD does not specify alternative compliance methods: The text does not provide for alternative means of compliance or exemptions. If an operator believes a different procedure will achieve equal safety, that pathway is not described and would likely require separate regulatory approval, but the AD does not detail how to seek it.

9. Dates and identifiers repeated: The AD identifier AD/F100/79 (9/2006) appears multiple times; operators should check they are referencing the correct AD number and edition. The AD’s effective date is 31 August 2006; the issue date is 21 July 2006.

10. Absence of penalty language: Because the AD does not set out enforcement or penalties explicitly, operators should not assume leniency or statutory mechanisms are absent. The AD’s technical requirements should be treated as mandatory; however, the AD itself does not state the consequences for non-compliance within its text.

These items are all directly inferable from the AD text provided. They emphasise careful verification of applicability, the need to follow EASA-approved SB versions, awareness of the operational grounding consequence where discrepancies are discovered, and the practical tasks of parts procurement and maintenance planning.

The AD prescribes a clear, three-step compliance pathway tied to specific documents and timing. Follow these steps, as expressed in the AD text.

1. Establish applicability: Confirm the aircraft is a F28 Mark 0100 and that its installed PSUs are Honeywell/Grimes P/N 10-1178-XX series or 10-1571-XX series. Also check maintenance logbooks and modification records to determine whether Fokker Service Bulletin SBF100-25-070 dated 15 March 1995 has been embodied on the aircraft. If that SB has been applied, the AD does not apply to that aeroplane (Applicability).

2. Obtain the correct service instructions: Secure Fokker Service Bulletin SBF100-25-108 dated 31 March 2006, or any later EASA approved revision. The AD requires all inspections and rectifications be performed in accordance with Section 3 - Accomplishment Instructions - of that Service Bulletin or a later EASA approved revision (Requirement 1; Requirement 2). Ensure the SB revision you hold is EASA approved; the AD limits acceptable revisions to those with EASA approval.

3. Schedule and carry out the inspection: Complete the inspection of the affected PSU panel interface connectors in accordance with Section 3 of SBF100-25-108 within 36 months after the AD’s effective date, which is 31 August 2006 (Compliance). Although the AD provides a 36-month window, plan for availability of parts and resources in case rectification is required.

4. If discrepancies are found, rectify immediately: If the inspection identifies any discrepancies, carry out the rectification actions specified in Section 3 of SBF100-25-108, or a later EASA approved revision, before further flight (Requirement 2; Compliance). The AD text specifically contemplates replacement of the affected PSU Panel J1 and J2 interface connector gaskets as the remedial action where necessary. Therefore, ensure replacement parts meet the manufacturer’s specification and the Service Bulletin instructions.

5. Parts procurement and conformity: Source replacement gaskets and any additional parts to the specification described in SBF100-25-108 and the manufacturer’s corrective action. The Background notes that the manufacturer narrowed gasket thickness tolerances; ensure replacement gaskets conform to the revised tolerances as specified by the SB or the manufacturer.

6. Document the work: Although the AD does not specify record-keeping procedures within its text, good practice is to record inspection results, any discrepancies found, and details of rectification (parts used, SB revision followed, technicians, date). This documentation will support proof of compliance during audits and maintenance oversight.

7. Use only EASA-approved revisions: If a later revision of SBF100-25-108 is used, confirm it carries EASA approval. The AD allows "later EASA approved revision[s]" of the Service Bulletin as acceptable for compliance; using a revision without EASA approval would not satisfy the AD’s own wording.

8. Coordinate with regulator as needed: The AD references CAA-NL AD NL-2006-008 and EASA Approval 2006-0193. If there is uncertainty about SB approvals or interpretation of the Service Bulletin instructions, consult the relevant regulator or the Authority that issued the AD (the document is signed by a CASA delegate) for clarification. The AD itself does not lay out a formal alternative compliance request process; any deviation from the SB instructions would likely require regulator engagement.

9. Plan for operational impact: Because rectification must be completed before further flight if discrepancies are found, schedule inspections at times when maintenance resources and replacement parts are available to avoid extended aircraft out-of-service periods.

10. Verify completion within deadlines: Although the AD’s effective date was 31 August 2006, the inspection deadline was within 36 months thereafter. Ensure that the inspection and any rectification were completed and recorded within the AD’s specified timeframe if you are confirming historical compliance.

In sum, compliance is achieved by verifying applicability, following Section 3 of SBF100-25-108 (31 March 2006) or a later EASA-approved revision, conducting the inspection within 36 months, replacing J1 and J2 gaskets or otherwise rectifying defects found, and ensuring rectification is done before further flight. The AD’s text ties compliance to EASA-approved technical instructions and requires operators to manage parts, labour and scheduling to meet the AD’s constraints.