{"id":"F2006B01902","name":"AD/A320/159 Amdt 1 - Emergency Escape Path Marking System Power Supplies","slug":"ad-a320-159-amdt-1-emergency-escape-path-marking-system-power-supplies","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41111,"registerId":"commonwealth-F2006B01902-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/A320/159 Amdt 1 - Emergency Escape Path Marking System Power Supplies","content":"![](image.001.png)\n\n![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/A320/159 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/A320/159\n\nAmdt 1\n\n  \n\nEmergency Escape Path Marking System Power Supplies\n\n  \n12/2004\n\nApplicability: Airbus A319, A320 and A321 series aeroplanes all serial numbers, that are equipped with the Emergency Power Supply Units (EPSU) of the Floor Proximity Emergency Escape Path Marking System (FPEEPMS) Bruce Part Number (P/N) 100865.\n\nNote 1: Action is not required for aeroplanes with EPSUs having Diehl P/N 3214-51, 3214-52, 3214-54 or 3214-55 if a Bruce EPSU P/N 100865 is not installed.\n\nRequirement: 1. For aeroplanes equipped with Diehl EPSU P/N 3214-51, 3214-52, 3214-54 or 3214-55 and Bruce EPSU P/N 100865 \\- If not previously accomplished in accordance with AD/A320/159 original issue, carry out the following in accordance with Airbus Service Bulletin (SB) A320-33-1041 or later revision approved by the DGAC:\n\na. Remove Bruce EPSU P/N 100865,\n\nb. Remove Diehl EPSU P/N 3214-51, 3214-52, 3214-54 or 3214-55,\n\n    c. Install improved Diehl EPSU P/N 3214-54-10 or 3214-55-10, and\n\n    d. Modify the wiring.\n\n    2. For aeroplanes equipped with Diehl EPSU P/N 3214-54-10 or 3214-55-10 and Bruce EPSU P/N 100865 \\- Carry out the following in accordance with Airbus Service Bulletin (SB) A320-33-1041 or later revision approved by the DGAC:\n\n    Remove Bruce EPSU 100865, and\n\n    b. Modify the wiring.\n\nNote 2: DGAC AD F-2004-121 R1 (EASA Approval 2004-10126) refers.\n\nCompliance: For Requirements 1 and 2 \\- Before 31 December 2005.\n\nThis Amendment becomes effective on 25 November 2004.\n\nAirbus Industrie A319, A320 and A321 Series Aeroplanes\n\nAD/A320/159 Amdt 1 (continued)\n\nBackground: The existing system architecture of the Bruce FPEEPMS does not comply with the requirements of the JAR/FAR 25.812 (I)(1) since none of the connected FPEEPMS including the Exit identifiers will illuminate in the event of an accident leading to a vertical separation of the fuselage forward of door number 1.\n\nThe original issue of this Directive required the replacement of EPSUs. This amendment clarifies which EPSUs are to be replaced.\n\nThe original issue of this Airworthiness Directive became effective on 30 September 2004.\n\n![](image.002.png)  \n\nJames Coyne\n\nDelegate of the Civil Aviation Safety Authority 15 October 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 3 November 2004.","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 an amendment to an existing Airworthiness Directive. The original AD required replacement of EPSUs; this amendment merely clarifies which specific units need replacement versus which only need the Bruce unit removed. The scope remains tightly focused on the original safety issue (emergency escape path marking power supplies) and has not expanded beyond correcting the unsafe condition identified in the original directive."},"complexity_factors":["Short, single-purpose document (2 pages) focused on one specific technical modification","Limited conditional logic: only two requirement pathways based on existing equipment configuration","7 specific part numbers referenced but clearly distinguished","Single cross-reference to Airbus Service Bulletin A320-33-1041 for technical instructions","No nested exceptions or complex definitional sections","Clear compliance date with no tiered or conditional deadlines"],"plain_english_summary":"This AD orders operators of certain Airbus A319/A320/A321 aircraft to correct a hazard in emergency floor lighting: Bruce-brand EPSUs combined with specific Diehl units can fail if the forward fuselage breaks away, risking loss of escape-path illumination. Affected aircraft must have the Bruce unit removed—and old Diehl EPSUs replaced and wiring modified where required—by 31 December 2005 to ensure lights remain operable in structural breakup scenarios."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"This amendment does not introduce a new safety objective but clarifies and narrows the original directive's instructions by specifying exactly which EPSU part numbers are to be removed and which improved Diehl part numbers are to be installed (Requirement section and Note 1). The original AD required replacement of EPSUs but left ambiguity about which EPSUs were affected; this amendment removes that ambiguity by listing Bruce and Diehl P/Ns and providing two distinct work paths depending on the Diehl unit installed. Mechanically, the scope shifted from a general replacement requirement to a targeted parts-and-wiring correction for aeroplanes with Bruce P/N 100865 (and the listed Diehl P/N combinations)."},"complexity_factors":["Clear, short directive limited to one aircraft family (A319/A320/A321)","Small number of defined part numbers (Bruce P/N 100865; Diehl P/N 3214-51/52/54/55 and improved 3214-54-10/55-10)","Two alternative requirement paths (requirements 1 and 2) depending on installed Diehl P/N","External cross-reference to Airbus Service Bulletin A320-33-1041 (or later DGAC-approved revision)","Compliance deadline is single fixed date (31 December 2005)","One regulatory cross-reference (non-compliance with JAR/FAR 25.812(i)(1))","Amendment revokes and replaces an earlier AD but does not add multi-part conditional logic or numerous exceptions"],"plain_english_summary":"**What this directive does**\n\n- This is an Airworthiness Directive (AD) that sets mandatory corrective work for certain Airbus A319/A320/A321 aeroplanes equipped with specific Emergency Power Supply Units (EPSUs) for the floor proximity emergency escape path marking system (FPEEPMS). (Applicability)\n\n**Who is affected**\n\n- Operators of Airbus A319, A320 and A321 aeroplanes of any serial number that have a Bruce EPSU with Part Number (P/N) 100865 installed. (Applicability)\n\n- If an aeroplane does not have a Bruce P/N 100865 installed, the AD generally does not apply, even if it has Diehl EPSUs of other part numbers. (Note 1)\n\n**What must be done (the mechanical steps)**\n\n- If the aeroplane has both a Bruce EPSU P/N 100865 and an older Diehl EPSU (P/N 3214-51, 3214-52, 3214-54 or 3214-55):\n  - Remove the Bruce EPSU (P/N 100865);\n  - Remove the older Diehl EPSU (one of P/N 3214-51/52/54/55);\n  - Install the improved Diehl EPSU (P/N 3214-54-10 or 3214-55-10);\n  - Modify the wiring as detailed in the Airbus Service Bulletin. (Requirement 1)\n\n- If the aeroplane already has an improved Diehl EPSU (P/N 3214-54-10 or 3214-55-10) together with a Bruce EPSU P/N 100865:\n  - Remove the Bruce EPSU (P/N 100865);\n  - Modify the wiring as detailed in the Airbus Service Bulletin. (Requirement 2)\n\n- All removals/installs/wiring changes must follow Airbus Service Bulletin A320-33-1041 (or a later revision approved by the French authority DGAC). (Requirement 1 & 2)\n\n**When it must be done**\n\n- The required actions must be completed before 31 December 2005. (Compliance)\n\n**Why the work is required**\n\n- The Bruce FPEEPMS architecture can fail to illuminate exit-related lighting (including exit identifiers) if the fuselage separates forward of door 1 in an accident. That configuration does not meet the relevant airworthiness requirement (JAR/FAR 25.812(i)(1)). The AD therefore requires removal of the Bruce EPSU and installation of an improved Diehl EPSU or wiring modification so the escape path lighting will operate as required. (Background)\n\n**Who pays and who decides**\n\n- Aircraft operators (airlines, leasing companies, MRO providers acting for operators) pay for the parts, labour and downtime required to remove/install EPSUs and modify wiring. (Requirements/Compliance)\n\n- The Civil Aviation Safety Authority (CASA) delegate issued the AD and requires compliance; the detailed technical steps are those in the Airbus Service Bulletin and any later DGAC-approved revision (technical approval by the state authority). (Requirement/DGAC note)\n\n**Costs, incentives and trade-offs**\n\n- Direct costs: parts (replacement Diehl EPSUs where required), labour and aircraft grounding time. Operators must decide when to schedule the work to minimise operational disruption. (Requirements/Compliance)\n\n- Implementation risk: wiring modifications introduce risk if not carried out per the approved Service Bulletin — this creates a need for qualified maintenance and quality control. (Requirement)\n\n- Market effect: the AD directs removal of a Bruce unit and installation of a Diehl unit in many cases, which concentrates demand for the improved Diehl P/N parts among affected operators. This could advantage suppliers of the Diehl unit and reduce demand for the Bruce unit on affected aircraft. (Requirements)\n\n- Compliance burden: the AD cross-references an external Service Bulletin and requires approval by a foreign authority (DGAC) for later revisions. That adds a dependency on the Service Bulletin's availability and any state-authority approvals. (Requirement/DGAC note)\n\n**Practical note for operators**\n\n- Check each aeroplane's EPSU part numbers. If Bruce P/N 100865 is not installed, the AD does not apply. If it is installed, follow the correct requirement path depending on the Diehl P/N present, and use Airbus SB A320-33-1041 (or DGAC-approved revision) to carry out parts removal, installation and wiring changes before the specified compliance date. (Applicability/Requirement/Compliance)\n\n\n"}},"importantCases":[],"_links":{"self":"/api/acts/ad-a320-159-amdt-1-emergency-escape-path-marking-system-power-supplies","history":"/api/acts/ad-a320-159-amdt-1-emergency-escape-path-marking-system-power-supplies/history","analysis":"/api/acts/ad-a320-159-amdt-1-emergency-escape-path-marking-system-power-supplies/analysis","conflicts":"/api/acts/ad-a320-159-amdt-1-emergency-escape-path-marking-system-power-supplies/conflicts","importantCases":"/api/acts/ad-a320-159-amdt-1-emergency-escape-path-marking-system-power-supplies/important-cases","documents":"/api/acts/ad-a320-159-amdt-1-emergency-escape-path-marking-system-power-supplies/documents"}}