{"id":"F2006B11150","name":"AD/LEARJET/32 Amdt 2 - Battery Vent System","slug":"ad-learjet-32-amdt-2-battery-vent-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56840,"registerId":"commonwealth-F2006B11150-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/LEARJET/32 Amdt 2 - Battery Vent System","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)  \nGates Learjet 24 & 25 Series Aeroplanes\n\nAD/LEARJET/32\n\nAmdt 2\n\n  \n\nBattery Vent System 6/87 DM\n\nApplicability: All Gates Learjet 24 and 25 series aircraft with the following S/Nos:\n\nGroup A \\- Learjet 24-218 and 24-230 to 24-357,\n\nLearjet 25-059, 25-061 and 25-066 to 25-373\n\nGroup B \\- Learjet 24-100 to 24-229 (except 24-218),\n\nLearjet 25-003 to 25-058 and 25-060\n\nRequirement: 1. Inspect the interior of the battery cases for evidence of fuel contamination. If evidence of fuel contamination exists inspect the fuel drain valves forward of the battery compartment for evidence of leakage. Replace any defective fuel drain valves.\n\n2. Modify the battery venting system according to the requirements of Gates Learjet SB 23/24/25-334B.\n\nNote: FAA AD 86-05-05 Amdt 39-5248 refers.\n\nCompliance: (a) For Para 1 and Group A Aircraft:\n\nWithin 25 hours time in service after 31 May 1986 and thereafter at intervals not exceeding 50 hours time in service until modified in accordance with paragraph 2 of this Requirement.\n\nFor Para 2 and Group A Aircraft:\n\nWithin 200 hours time in service after 31 May 1986.\n\n(b) For Para 1 and Group B aircraft:\n\nWithin 25 hours time in service after 4 June 1987 and thereafter at intervals not exceeding 50 hours time in service until modified in accordance with paragraph 2 of this Requirement.\n\nFor Para 2 and Group B aircraft:\n\nWithin 200 hours time in service after 4 June 1987.\n\nBackground: 1. To prevent fuel from being drawn into the battery vent system in the event of a fuel leak at the lower side of the fuselage. An instance of significant contamination has been reported from overseas.\n\n2. The effectivity statement of SB 23/24/25-334B contains aircraft which may have been modified to the configuration which is the subject of this Directive. These aircraft are designated Group B in this Directive.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"The Directive clarifies and refines applicability compared with the service bulletin by designating Group B aircraft that may already have the modified configuration and imposing distinct compliance timelines. The AD therefore alters scope and timing relative to the SB effectivity statement by capturing both unmodified and potentially previously modified airframes and mandating interim inspections until the SB modification is installed (see 'Background' and 'Applicability')."},"complexity_factors":["Distinct Applicability: multiple serial-number ranges split into Group A and Group B (administrative tracking; see 'Applicability').","Staged compliance deadlines: different start dates and time-in-service limits for para 1 and para 2 between groups (see 'Compliance (a)/(b)').","Interim recurring inspections required until modification is completed (inspect every 50 hours after an initial 25-hour check) — creates ongoing operational burden (see Requirement para 1 and Compliance).","Mandatory modification references an external service bulletin (Gates Learjet SB 23/24/25-334B) requiring operators to obtain and implement technical instructions not fully reproduced in the AD (see Requirement para 2).","Physical works: inspection of battery case interiors, potential replacement of fuel drain valves and installation of venting modification (practical access, parts and labour costs).","Recordkeeping and compliance monitoring to demonstrate inspections and modification within specified hours time in service."],"plain_english_summary":"This AD requires operators to inspect battery cases for fuel contamination, replace any leaking fuel drain valves, and modify the battery venting system per Gates Learjet SB 23/24/25-334B. It applies to specified Gates Learjet 24 and 25 serial numbers.\n\nThe Directive sets short, recurring inspection intervals until the mandatory modification is installed and assigns operators the cost and work of inspection, parts replacement and modification, with staged compliance deadlines for two groups of aircraft."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is Amendment 2 to an existing Airworthiness Directive, but the scope remains tightly focused on the original safety issue: preventing fuel contamination of battery vent systems on specific Learjet models. The amendment appears to refine the aircraft groupings and compliance dates without expanding beyond the original safety purpose."},"complexity_factors":["Two distinct aircraft groups with different serial number ranges requiring careful cross-referencing","Staggered compliance dates (1986 for Group A, 1987 for Group B) creating dual timelines","Dual requirements (inspection + modification) with different compliance intervals","Conditional logic: inspection interval only applies 'until modified' per paragraph 2","Reference to external technical document (Gates Learjet SB 23/24/25-334B) and FAA AD 86-05-05 for full implementation details","Nested applicability: Group B definition includes an exception ('except 24-218') within an exception"],"plain_english_summary":"This CASA Airworthiness Directive mandates safety work on battery vent systems of specified Gates Learjet 24 and 25 aircraft after fuel leaks were found that could let fuel enter battery vents and create a fire/explosion hazard. It affects owners/operators of two serial-number groups (older and newer airframes).\n\nRequired actions: inspect battery cases for fuel contamination every 50 flight hours (replace leaking fuel drain valves if found) and install the improved battery venting modification per the manufacturer’s Service Bulletin within 200 flight hours."}},"importantCases":[],"_links":{"self":"/api/acts/ad-learjet-32-amdt-2-battery-vent-system","history":"/api/acts/ad-learjet-32-amdt-2-battery-vent-system/history","analysis":"/api/acts/ad-learjet-32-amdt-2-battery-vent-system/analysis","conflicts":"/api/acts/ad-learjet-32-amdt-2-battery-vent-system/conflicts","importantCases":"/api/acts/ad-learjet-32-amdt-2-battery-vent-system/important-cases","documents":"/api/acts/ad-learjet-32-amdt-2-battery-vent-system/documents"}}