{"id":"F2006B01883","name":"AD/A320/137 Amdt 1 - Fuel Probes and Fuel Tank Level Sensors","slug":"ad-a320-137-amdt-1-fuel-probes-and-fuel-tank-level-sensors","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41079,"registerId":"commonwealth-F2006B01883-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/A320/137 Amdt 1 - Fuel Probes and Fuel Tank Level Sensors","content":"![](image.001.png)\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/A320/137 and issues the following AD under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nAirbus Industrie A319, A320 and A321 Series Aeroplanes\n\nAD/A320/137\n\nAmdt 1\n\n  \nFuel Probes and Fuel Tank Level Sensors 12/2003\n\nApplicability: A319 and A320 series aeroplanes, all manufacturers serial numbers (MSN) except those with Airbus modification 28904 embodied during production or Airbus Industrie Service Bulletin (SB) A320-28-1087 incorporated.\n\nA319 and A320 series aeroplanes, all MSN, with a first Additional Centre Tank (ACT) installed in accordance with Airbus modification 25714 embodied during production or Airbus Industrie SB A320-28-1081, except aeroplanes that had both Airbus modifications 28904 and 30196 embodied during production or have incorporated SB A320-28-1087.\n\nA319 and A320 series aeroplanes, all MSN, with a second ACT installed in accordance with Airbus modification 26131 embodied during production or Airbus Industrie SB A320-28-1081, except aeroplanes that had both Airbus modifications 28904 and 30492 embodied during production or have incorporated SB A320-28- 1087.\n\nA319 series aeroplanes, all MSN, with Airbus modifications 28238, 28162 and 28342 embodied during production, except aeroplanes that had Airbus modifications 28720, 28904 and 30227 embodied during production or have incorporated both SB’s A320- 28-1086 and A320-28-1087.\n\nRequirement: 1. Unless already accomplished modify the fuel tank probe electrical connectors in accordance with SB A320-28-1087.\n\n2. For A319 series aeroplanes with Airbus modifications 28238, 28162 and 28342 embodied during production, in addition to SB A320-28-1087, replace the fuel tank level sensors in accordance with SB A320-28-1086.\n\nNote: DGAC AD 2002-220(B) R1 refers.\n\nCompliance: For Requirements 1 and 2 \\- Remains unchanged as ‘Either before 31 December 2004 or within 4,000 hours’ time in service after the effective date of the original issue of this Directive, whichever occurs first’.\n\nThis Amendment becomes effective on 27 November 2003.\n\nAirbus Industrie A319, A320 and A321 Series Aeroplanes\n\nAD/A320/137 Amdt 1 (continued)\n\nBackground: The French Direction Générale de l’Aviation Civile (DGAC) has advised that investigations performed by Airbus Industrie have revealed a potential risk of a 28VDC short circuit, external to the fuel tank, to the fuel quantity indication wiring that enters the fuel tank may lead to overheating of the probes. This condition could result in ignition of fuel vapours within the fuel tank.\n\nAdditionally, the DGAC has advised that Airbus Industrie found, during their investigations, that the additional centre tanks do not meet the Joint Aviation Requirements (JAR) 25.969 for an expansion space of not less than 2% of tank capacity.\n\nThe original issue of this Directive required modification of the fuel probe electrical connectors and the lowering of the high-level fuel tank sensors in certain aeroplanes.\n\nThis amendment does not change the original requirements or compliance, it extends the applicability to aeroplanes not originally covered and incorporates minor editorial changes.\n\nThe original issue of this Directive became effective on 13 June 2002.\n\n![](image.002.png)  \n\nJim Coyne\n\nDelegate of the Civil Aviation Safety Authority 14 October 2003\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 5 November 2003.","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":4,"scope_assessment":{"changed":true,"description":"The amendment explicitly states it 'extends the applicability to aeroplanes not originally covered' while keeping the same technical requirements. The original 2002 directive covered specific fuel probe modifications; this 2003 amendment adds additional aircraft configurations (particularly those with first and second Additional Centre Tanks and specific production modifications) that were excluded from the original scope. This represents a modest expansion of regulatory reach rather than a fundamental shift in purpose."},"complexity_factors":["Multiple nested applicability exceptions (4 separate categories with 'except' clauses)","Heavy reliance on external technical documents (Airbus Service Bulletins A320-28-1087 and A320-28-1086) without reproducing their content","Cross-reference to French regulatory document (DGAC AD 2002-220(B) R1)","Technical aviation terminology requiring specialised knowledge (MSN, ACT, embodied modifications, time in service)","Dual compliance pathways (calendar date vs flight hours) with 'whichever occurs first' logic","Amendment structure requires reading in conjunction with superseded original directive to fully understand scope"],"plain_english_summary":"This CASA Airworthiness Directive revokes and replaces an earlier AD and requires modification of fuel‑tank probe electrical connectors — and replacement of fuel‑level sensors on some A319s — to eliminate a risk of wiring shorting to 28V power, which can overheat probes and ignite fuel vapours. It applies to many A319/A320/A321 aircraft with Additional Centre Tanks unless already modified; this amendment expands covered types but keeps the original compliance deadlines."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"This amendment extends the scope of the original AD by adding additional aeroplane configurations to the Applicability section (more serial numbers/configurations are now captured) while keeping the original mandated tasks and the compliance deadline unchanged. In short: the technical requirements and timing remain the same, but more aircraft are now required to comply."},"complexity_factors":["Multiple, detailed applicability sub‑sets referencing specific Airbus modification numbers (e.g. 25714, 26131, 28238, 28162, 28342, 28904, 30196, 30492)","Exceptions within applicability (aircraft excluded if they have other specific mods embodied or certain SBs incorporated)","Two separate mandated actions (connector modification and, for a subset, sensor replacement)","Cross‑references to multiple Airbus Service Bulletins (A320-28-1087 and A320-28-1086)","Fixed compliance window that references the original AD’s effective date rather than a fresh calendar date","Reference to an external foreign authority AD (DGAC AD 2002-220(B) R1)","Short background section that introduces technical standards (JAR 25.969) and factual findings","Amendment modifies scope (extends applicability) while leaving requirements and timing unchanged, requiring readers to compare original AD and amended text"],"plain_english_summary":"**What this airworthiness directive (AD) requires**\n\n- This AD orders specific maintenance work on fuel probes (electrical connectors) and, for some A319s, fuel tank level sensors. (See “Requirement”.)\n\n**Who is affected**\n\n- Operators and owners of Airbus A319 and A320 series aeroplanes (and A321 series are named in the heading) that match the detailed configurations and modification history in the AD’s Applicability section. The AD identifies aircraft by which Airbus production modifications (mod numbers) have or have not been embodied, and by whether one or two Additional Centre Tanks (ACTs) have been installed. (See “Applicability”.)\n\n**The specific actions required**\n\n- Requirement 1: Modify the fuel tank probe electrical connectors in accordance with Airbus Service Bulletin (SB) A320-28-1087, unless that work has already been done. (Requirement 1.)\n\n- Requirement 2 (additional, limited to certain A319s): For A319s with Airbus modifications 28238, 28162 and 28342 embodied during production, replace the fuel tank level sensors in accordance with SB A320-28-1086, in addition to the connector modification. (Requirement 2.)\n\n**When the work must be done**\n\n- The compliance deadline is unchanged from the original AD: either before 31 December 2004 or within 4,000 flight hours after the effective date of the original AD, whichever comes first. (Compliance.)\n\n**Why the AD was issued (stated safety rationale)**\n\n- Investigations by Airbus (reported by the French DGAC) found a potential for an external 28 V DC short circuit to the fuel quantity wiring entering the fuel tank. That short could overheat probes and possibly ignite fuel vapours inside the tank. (Background.)\n\n- Airbus also found that some Additional Centre Tanks do not meet the regulatory requirement for an expansion space of at least 2% of tank capacity (JAR 25.969), which relates to fuel vapour/pressure behaviour in the tank. (Background.)\n\n**What changed in this amendment**\n\n- The amendment does not change the technical tasks required or the compliance time, but it extends the list of aeroplanes covered by the AD (expands applicability) and makes minor editorial revisions. (Background; Applicability.)\n\n**Practical implications, costs and incentives**\n\n- Who pays and who acts: Aircraft operators (or their maintenance providers) must schedule and pay for the work and any parts called for in the referenced SBs. The work must be performed according to the Airbus SB instructions. (Requirement; Applicability.)\n\n- Downtime and labour: Compliance will require maintenance time and potential out-of-service time for affected aeroplanes. Operators face opportunity costs from scheduling maintenance slots and possible short-term capacity reduction.\n\n- Parts and service market: The market for parts and qualified maintenance services for these SBs will see increased demand. That benefits suppliers and maintenance organisations able to supply the required parts and carry out the modifications; it may disadvantage operators if approved parts or specific procedures constrain independent MRO choices.\n\n- Compliance burden: Operators must check each aeroplane’s serial number and embodiment of specific Airbus modifications or SBs to determine applicability, then record and schedule the mandated work within the compliance window. That creates administrative tracking and documentation work.\n\n- Implementation risks and substitution effects: Delays in parts supply, limited maintenance capacity, or misidentifying an aeroplane’s modification status could delay compliance. Operators may choose different fleet deployment or capacity planning to manage aircraft out-of-service periods.\n\n**Regulatory references to note**\n\n- The AD mandates compliance with Airbus SB A320-28-1087 (connectors) and SB A320-28-1086 (sensors for certain A319s). It also refers to the French DGAC AD 2002-220(B) R1. (Requirement; Note.)\n\n**Section citations (for readers who want to check the AD text)**\n\n- Applicability: lists affected models and the modification/SB exceptions.\n- Requirement: numbered items 1 and 2 describing the mandated maintenance actions.\n- Compliance: timing requirement (unchanged).\n- Background: technical rationale and statement that this amendment extends applicability.\n\n(Where the AD mentions specific Airbus modification numbers and SBs, operators must match those identifiers to their aircraft records to determine whether the AD applies.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-a320-137-amdt-1-fuel-probes-and-fuel-tank-level-sensors","history":"/api/acts/ad-a320-137-amdt-1-fuel-probes-and-fuel-tank-level-sensors/history","analysis":"/api/acts/ad-a320-137-amdt-1-fuel-probes-and-fuel-tank-level-sensors/analysis","conflicts":"/api/acts/ad-a320-137-amdt-1-fuel-probes-and-fuel-tank-level-sensors/conflicts","importantCases":"/api/acts/ad-a320-137-amdt-1-fuel-probes-and-fuel-tank-level-sensors/important-cases","documents":"/api/acts/ad-a320-137-amdt-1-fuel-probes-and-fuel-tank-level-sensors/documents"}}