{"id":"F2006B09817","name":"AD/F28/82 - Fuel Boost Pump Wiring","slug":"ad-f28-82-fuel-boost-pump-wiring","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54751,"registerId":"commonwealth-F2006B09817-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F28/82 - Fuel Boost Pump Wiring","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nFokker F28 Series Aeroplanes\n\nAD/F28/82 Fuel Boost Pump Wiring 1/2000 DM\n\nApplicability: Model F.28 Mk.1000 through Mk.4000 series aeroplanes.\n\nRequirement: 1. Perform a one time review of the aeroplane Maintenance Logs in accordance with Part 1 of the Accomplishment Instructions of Fokker Service Bulletin (SB) F28/28-046 dated 1 September 1999.\n\n    2. If, either during the Requirement 1 review or during subsequent service of the aeroplane, reports are found of resettable or non-resettable tripping of the Fuel Boost Pump circuit breakers, perform corrective actions in accordance with Part 2 of the Accomplishment Instructions of SB F28/28-046 dated 1 September 1999.\n\n    3. Check for signs of fuel leakage from the Boost Pump wiring conduits in accordance with Part 1 of the Accomplishment Instructions of SB F28/28-046 dated 1 September 1999.\n\n    4. If, during the Requirement 3 inspection or any other inspection, fuel leakage is found from the Boost Pump wiring conduit on the rear spar of the wing, perform corrective action in accordance with Part 2 of the Accomplishment Instructions of SB F28/28-046 dated 1 September 1999.\n\n    5. Replace the existing three single wires inside the Boost Pump metal conduit with three twisted wires, protected by a Polyamide braided wire sleeve in accordance with Part 3 of the Accomplishment Instructions of SB F28/28-046 dated 1 September 1999.\n\nAccomplishment of Requirement 5 is considered terminating action for Requirements 1, 2 and 3.\n\nNote 1: Netherlands AD 1999-114 (A) refers.\n\nCompliance: 1. Within 30 days after the effective date of this Directive.\n\n    2. Within the ten days following the occurrence.\n\nNote 2: During the ten days subsequent to the report of resettable or non-resettable circuit breaker tripping, operation with an unserviceable boost pump is only allowed provided that the boost pump circuit breaker is pulled and secured. Both the circuit breaker and the boost pump switch are to be placarded as ‘INOPERATIVE’.\n\nMMEL item 28-22-1 and the relevant Operating Procedure also pertain to this subject.\n\n    3. Within 30 days after the effective date of this Directive and thereafter at intervals not to exceed 90 days.\n\n    4. Before further flight.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n    5. In accordance with the following table:\n\n| Aircraft hours total time in service on the effective date of this Directive | Compliance period after the effective date of this Directive |\n| ---------------------------------------------------------------------------- | ------------------------------------------------------------ |\n| equal to or exceeding 40,000                                                 | one year                                                     |\n| less than 40,000                                                             | two years                                                    |\n\nThis Airworthiness Directive becomes effective on 8 December 1999.\n\nBackground: The Fokker B.V. Fuel System Safety Programme investigation of the boost pump wiring on Fokker F28 aeroplanes revealed that the boost pump wiring insulation layers can be damaged during installation/removal and/or chafing of the wiring. Additionally, signs of arcing between the wiring and the conduit was detected in two boost pump wiring metal conduits located in the collector tank.\n\nThis Directive requires a one time review of aircraft maintenance documentation, repetitive checks for signs of fuel leakage from the boost pump wiring conduits inside the Main Landing Gear strut bays and corrective action as necessary. The Directive also requires eventual replacement of the existing three single wires in the boost pump metal conduit.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive with a focused, narrow scope addressing a specific safety defect in Fokker F28 aircraft wiring. It has not expanded beyond its original purpose of addressing the fuel boost pump wiring insulation and arcing risks identified in the Fokker B.V. Safety Programme investigation."},"complexity_factors":["Multiple cross-references to external technical document (Fokker Service Bulletin F28/28-046) without reproducing those instructions in the text","Conditional logic: Requirements 2 and 4 only trigger if specific findings occur during inspections","Tiered compliance schedule with five different deadlines depending on circumstance (immediate, 10 days, 30 days, 90-day intervals, 1-2 years based on flight hours)","Technical aviation terminology requiring domain knowledge (MMEL, circuit breakers, collector tank, rear spar, conduits)","Interdependency between requirements: Requirement 5 terminates Requirements 1-3, creating a logical dependency chain"],"plain_english_summary":"This Airworthiness Directive requires operators and maintenance crews of Fokker F28 Mk1000–Mk4000 aircraft to inspect the fuel boost pump wiring for damage, evidence of arcing, and fuel leakage, take prompt corrective action (including grounding aircraft with leaking conduits), and complete a permanent wiring replacement on a specified schedule. It addresses a chafing/insulation failure that, near fuel vapour, creates a significant fire and explosion risk."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD is tightly focused on a specific, safety-related problem (boost pump wiring chafing, fuel leakage and arcing) identified by a Fokker investigation. The measures (log review, inspections, corrective action, and eventual wiring replacement) are directly aligned with that original safety purpose. The instrument does not broaden the area of regulation beyond those wiring and conduit issues described in the background and Service Bulletin."},"complexity_factors":["Single-aircraft type focus (Fokker F28 Mk.1000–Mk.4000) reduces scope complexity","Five discrete requirements with clear sequencing (Requirements 1–5)","External dependence on one Service Bulletin (Fokker SB F28/28-046) for technical detail","A small number of conditional paths: corrective action required if specific findings (circuit breaker trips or fuel leakage)","Repetitive inspection interval introduced (every 90 days) until terminating action completed","Two-tier compliance window for terminating action based on airframe hours (>=40,000 vs <40,000)","Cross-reference to Netherlands AD and MMEL/operating procedures but limited number of cross-references overall"],"plain_english_summary":"**What this directive does (in plain language)**\n\n- This Airworthiness Directive (AD) applies to Fokker F28 series aeroplanes (models F.28 Mk.1000 through Mk.4000).  It addresses a safety problem with the electrical wiring for the fuel boost pump.\n\n- Mechanically, it orders five things for operators to do:\n  - Review the aircraft's maintenance logs to find any past reports of fuel boost pump circuit breaker tripping (Requirement 1).\n  - If you find reports of circuit breaker trips (or if trips occur later in service), carry out corrective work prescribed in the Fokker Service Bulletin (SB) referenced in the AD (Requirement 2).\n  - Inspect the boost pump wiring conduit areas for signs of fuel leakage, initially and then repeatedly at set intervals (Requirement 3).\n  - If fuel leakage is found from the boost pump wiring conduit on the wing rear spar, carry out the corrective work set out in the SB (Requirement 4).\n  - Replace the three existing single wires inside the boost pump metal conduit with three twisted wires protected by a polyamide braided sleeve, following the SB instructions (Requirement 5). Completing this replacement (Requirement 5) stops the need for the log review, corrective-trip response and the recurrent inspections called for in Requirements 1–3 (it is the \"terminating action\").\n\n- Timelines and operating constraints:\n  - The initial log review and the first inspection are due within 30 days of the AD taking effect (Compliance for Requirements 1 and 3).  If a circuit breaker trip is discovered, corrective action must be done within 10 days after the trip report (Requirement 2 compliance).  If fuel leakage is found during an inspection, corrective action must be done before further flight (Requirement 4).\n  - The full wiring replacement (Requirement 5) must be done within one year for aeroplanes with 40,000 or more total hours on the effective date, and within two years for those with less than 40,000 hours.\n  - If a boost pump becomes unserviceable because of circuit breaker tripping, the aircraft may be operated for up to ten days provided the boost pump circuit breaker is pulled and secured and the circuit breaker and boost pump switch are placarded \"INOPERATIVE\" (Note 2). The Minimum Equipment List (MMEL) item and operating procedures referenced also apply.\n\n- Why the AD was issued (stated reason):\n  - A Fokker safety investigation found that boost pump wiring insulation can be damaged during installation/removal or by chafing, and that arcing between wiring and metal conduit had been detected in some collector-tank conduits. The AD follows the manufacturer Service Bulletin that prescribes inspections, corrective work and a wiring design change to reduce those risks.\n\n**Who it affects and who pays**\n\n- Affected parties: Operators/owners of Fokker F28 Mk.1000–Mk.4000 aeroplanes and their maintenance organisations. CASA enforces compliance.\n\n- Who pays: The operator pays for the inspections, any corrective repairs, parts (replacement wiring and protective sleeve), labour and aircraft downtime. If a repair requires parts or specialised work from the manufacturer or approved shops, those costs and the scheduling impact fall to the operator.\n\n**What decisions change for operators**\n\n- Operators must add a short-term programme of log review and recurring inspections (every 90 days after the initial check) unless they perform the terminating wiring replacement.\n- If circuit breaker trips are found, operators must perform specific corrective actions within 10 days and follow the temporary operating limitation (pulling the circuit breaker, placarding) while awaiting repair.\n- Operators must schedule and budget for the wiring replacement within the one- or two-year window depending on aircraft hours; once replaced, the recurrent inspections and log-review requirement end.\n\n**Trade-offs, costs and risks (practical considerations)**\n\n- Direct costs: labour, replacement wiring and protective sleeve, inspection time, and aircraft downtime while the work is done.\n- Scheduling/opportunity cost: aircraft out of service for inspections/repairs or for the terminating wiring replacement may reduce available capacity.\n- Implementation risk: access to wiring conduits (inside landing-gear bays and collector tanks) can be technically challenging; some corrective actions may require specialised maintenance steps in the Fokker Service Bulletin.\n- Compliance burden: the AD sets a mixture of short timelines (30 days for initial actions, 10 days for corrective action after a trip) and recurring inspections (every 90 days) which increase administrative and maintenance workload until the terminating action is completed.\n- Concentrated benefits vs diffuse costs: the safety benefit (reduced risk of wiring chafing, fuel leakage and arcing) accrues to operators and passengers of the affected fleet; costs are concentrated on the relatively small set of F28 operators required to do the work.\n- Reliance on Service Bulletin: the AD delegates the technical detail to a Fokker Service Bulletin (SB F28/28-046 dated 1 Sep 1999). Operators must obtain and follow that SB to meet the AD. This creates dependency on the SB's availability and clarity.\n\n**How the AD changes behaviour and oversight**\n\n- Maintenance crews will monitor boost pump circuit breaker events more actively, inspect wiring conduits periodically, and implement a wiring design change within a fixed timeframe. Regulatory oversight (Civil Aviation Safety Authority) will enforce these requirements.\n\n**Key textual pointers**\n\n- The directive sets out the five Requirements (1–5), compliance timing for each, and describes the replacement (Requirement 5) as terminating action for Requirements 1–3. The AD references the Fokker Service Bulletin for the technical procedures and the Netherlands AD 1999-114 (A) as related material.\n\n"}},"importantCases":[],"_links":{"self":"/api/acts/ad-f28-82-fuel-boost-pump-wiring","history":"/api/acts/ad-f28-82-fuel-boost-pump-wiring/history","analysis":"/api/acts/ad-f28-82-fuel-boost-pump-wiring/analysis","conflicts":"/api/acts/ad-f28-82-fuel-boost-pump-wiring/conflicts","importantCases":"/api/acts/ad-f28-82-fuel-boost-pump-wiring/important-cases","documents":"/api/acts/ad-f28-82-fuel-boost-pump-wiring/documents"}}