{"id":"F2005L04134","name":"AD/LJ45/8 - Engine Electrical Wire Bundles","slug":"ad-lj45-8-engine-electrical-wire-bundles","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":40120,"registerId":"commonwealth-F2005L04134-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Learjet 45 Series Aeroplanes","sectionType":"division","heading":"Learjet 45 Series Aeroplanes","content":"### Learjet 45 Series Aeroplanes\n\n| AD/LJ45/8 | Engine Electrical Wire Bundles | 2/2006 DM |\n| --------- | ------------------------------ | --------- |\n\n```html\n

Applicability:

Learjet Model 45 aeroplanes, serial numbers (S/N) 45-005 through 45-273 inclusive and 45-2001 through 45-2029 inclusive.

Requirement:

1. Modify the electrical wire bundle for the alternator on the left- hand engine and perform a general visual inspection of the left and right engines to make sure that the proper clearances are maintained between all wiring harnesses and engine tubing. All actions are to be carried out in accordance with the Accomplishment Instructions of the applicable Bombardier Alert Service Bulletin (ASB) as follows:

Aeroplane S/N Range

45-2001 through 45-2029 inclusive
45-005 through 45-273 inclusive

ASB

SB A40-71-01, dated 29 September 2005
SB A45-71-4, dated 29 September 2005

Note 1: For the purposes of this Directive, a general visual inspection is defined as \"A visual examination of an interior or exterior area, installation or assembly to detect obvious damage, failure or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to ensure visual access to all surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight or droplight and may require removal or opening of access panels or doors. Stands, ladders or platforms may be required to gain proximity to the area being checked.\"

2. Correct improper clearances detected during the Requirement 1 inspection in accordance with the applicable ASB.

3. For aeroplanes with serial numbers identified below, replace the fuses for the hydraulic shutoff valves with fuses having higher amperage in accordance with the Accomplishment Instructions of the following applicable Bombardier Service Bulletin (SB):

Aeroplane S/N Range

45-2001 through 45-2015 inclusive
45-005 through 45-254 inclusive

SB

SB 40-24-01, dated 22 April 2005
SB 45-24-6, dated 22 April 2005

\n```\n\n| | Later revisions of the above SBs, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2005-24-13, are considered acceptable for compliance with the equivalent Requirements of this Directive. |\n| ----------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| | Note 2: FAA AD 2005-24-13 Amdt 39-14393 refers. |\n| Compliance: | For Requirement 1 - Within 50 hours time in service after the effective date of this Directive. |\n| | For Requirement 2 - Before further flight after completing the Requirement 1 inspection. |\n| | For Requirement 3 - Concurrent with or prior to completing Requirement 1. |\n| | This Airworthiness Directive becomes effective on 20 December 2005. |\n| Background: | The FAA has received a report of a fire in the left-hand engine nacelle. Investigation revealed that an electrical wire bundle for the engine alternator had chafed a hole in a hydraulic line. This condition, if not corrected, could result in a fire in the engine nacelle. |\n| | This Directive requires modification of the electrical wire bundle for the alternator on the left-hand engine, inspecting for clearance between wire harnesses and engine tubing for each engine together with any necessary corrective actions. The Directive also requires, on some aeroplanes, the replacement of the fuses for the hydraulic shutoff valves with fuses having higher amperage. |\n\n![](image.001.png) \nCharles Lenarcic \nDelegate of the Civil Aviation Safety Authority\n\n15 December 2005","sortOrder":0},{"sectionNumber":"AD/LJ45/8","sectionType":"part","heading":"AD/LJ45/8","content":"## AD/LJ45/8","sortOrder":1},{"sectionNumber":"Engine Electrical Wire Bundles","sectionType":"part","heading":"Engine Electrical Wire Bundles","content":"## Engine Electrical Wire Bundles","sortOrder":2},{"sectionNumber":"2/2006 DM","sectionType":"part","heading":"2/2006 DM","content":"## 2/2006 DM","sortOrder":3}],"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"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive addressing a specific safety defect (engine fire risk from chafed wiring). The scope remains tightly focused on the original safety issue identified — preventing engine fires through wiring modifications, inspections, and fuse upgrades. No scope creep is evident."},"complexity_factors":["Multiple serial number ranges with different applicable service bulletins (SBs)","Cross-references to external manufacturer documents (Bombardier Service Bulletins) that are not reproduced in the directive itself","Conditional requirements based on aircraft serial number (Requirement 3 only applies to subset of affected aircraft)","Reference to FAA AD and AMOC (Alternate Method of Compliance) provisions for alternative compliance paths","Specific technical terminology requiring definitions (e.g., 'general visual inspection' defined in Note 1)","Staggered compliance deadlines depending on which requirement is being addressed"],"plain_english_summary":"This Airworthiness Directive requires operators of specified Learjet 45 serials (45‑005–45‑273 and 45‑2001–45‑2029) to modify the left‑engine alternator wiring, inspect both engines for wire‑to‑tube proximity, rectify any chafing risk before further flight, and fit higher‑capacity fuses on certain aircraft. It responds to an FAA report of an engine fire caused by wiring chafing a hydraulic line. Affected Australian operators must comply within the directive’s timeframes (generally within 50 flight hours; effective 20 December 2005)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD is narrowly focused on the safety issue identified in the background (wiring chafing that could puncture hydraulic lines and cause a fire). It requires modification, inspection and, for some serials, a fuse change; these actions are directly tied to the original safety concern and do not expand the AD beyond that corrective purpose."},"complexity_factors":["Short instrument with three numbered requirements","Two distinct serial-number ranges for applicability plus smaller subsets for Requirement 3","Cross-references to multiple Bombardier Alert/Service Bulletins (ASB/SB)","Acceptance of later SB revisions if FAA-approved as an AMOC (external dependency)","One defined inspection term (Note 1: definition of \"general visual inspection\")","Clear, short compliance timing rules (50 hours TIS; before further flight; concurrent)"],"plain_english_summary":"**What this instrument does (mechanically)\n\n- Requires specific maintenance actions for certain Learjet 45 aeroplanes (serial numbers listed).\n- Requirement 1: Modify the electrical wire bundle for the alternator on the left-hand engine and carry out a \"general visual inspection\" of both left and right engines to confirm required clearances between wiring harnesses and engine tubing. The actions must follow the Accomplishment Instructions in the Bombardier Alert Service Bulletin (ASB) identified for the aeroplane serial-number range. (See the AD for the exact ASB references.)\n- Requirement 2: If the inspection in Requirement 1 finds any improper clearances, those must be corrected in accordance with the applicable ASB before further flight.\n- Requirement 3: For specified serial-numbered aeroplanes, replace the fuses for the hydraulic shutoff valves with higher‑amperage fuses per the applicable Bombardier Service Bulletin (SB).\n- Timing: Requirement 1 must be done within 50 hours time in service after the AD’s effective date; Requirement 2 before further flight after completing Requirement 1; Requirement 3 concurrently with or before completing Requirement 1.\n- Acceptable compliance documents: Later revisions of the identified Bombardier SBs that have FAA approval as an Alternate Method of Compliance (AMOC) to the equivalent FAA Airworthiness Directive are acceptable for meeting this AD.\n\nWho is affected\n\n- Owners/operators of Learjet Model 45 aeroplanes with serial numbers 45-005 through 45-273 and 45-2001 through 45-2029 (inclusive). The AD also identifies smaller serial-number subsets for the fuse replacement requirement.\n\nWhy it matters (stated purpose and safety rationale)\n\n- The AD is issued in response to an FAA report of a left-engine nacelle fire caused when an electrical wire bundle chafed a hydraulic line. The stated safety objective is to remove the condition that could allow wiring to chafe hydraulic lines and possibly start a fire in the engine nacelle.\n\nPractical effects, costs and who decides\n\n- Who pays: aircraft owners/operators pay for the labour, parts and maintenance shop time needed to modify the wiring, perform inspections, carry out corrective actions, and (for some aircraft) replace fuses. Any increased cost of higher-amperage fuses and any required replacement hoses or harnesses is borne by the operator.\n- Who decides: the regulator (the AD authorising authority) mandates the actions; compliance rests with the operator and their maintenance organisation, which must apply the Bombardier ASB/SB instructions or FAA‑approved AMOCs.\n- Behaviour change: operators must schedule and complete the modification/inspection within the specified interval (50 hours TIS) and correct any deficiencies before further flight. Some aircraft will need the fuse change at the same time.\n\nTrade-offs, implementation risk and compliance burden\n\n- Compliance burden is moderate: the AD requires a physical modification and inspections that may require aircraft downtime, access panels, and qualified maintenance personnel. The AD defines \"general visual inspection\" narrowly (from touching distance, may need mirror/lighting/access panels) which constrains how inspections are done and may extend maintenance time if access is difficult (Note 1).\n- Opportunity cost: time in maintenance bays and parts procurement may displace other scheduled work and impose scheduling costs on operators.\n- Implementation risk: the AD relies on adherence to Bombardier ASBs or FAA‑approved AMOCs. If operators use an alternative method that is not FAA-approved, they may not be compliant. The AD leaves limited discretion to maintenance organisations beyond those approved SB procedures.\n- Effect on private enterprise: independent maintenance organisations can perform the work provided they use the specified service bulletin instructions or an approved AMOC. The AD neither mandates a particular supplier nor restricts who may perform the work beyond standard airworthiness requirements, but it ties compliance to manufacturer procedures and FAA approvals.\n\nConcrete mechanics to watch (where to look in the AD)\n\n- Requirement 1: left alternator wiring modification and general visual inspection of both engines (calls up Bombardier ASBs SB A40-71-01 or SB A45-71-4 depending on serial number).\n- Requirement 2: correction of improper clearances found in Requirement 1 (before further flight).\n- Requirement 3: fuse replacement for hydraulic shutoff valves on specified serial numbers (calls up Bombardier SB 40-24-01 or SB 45-24-6).\n- Timing: 50 hours TIS for Requirement 1; before further flight for Requirement 2; concurrent with or prior to completing Requirement 1 for Requirement 3.\n\nSummary sentence\n\nThis AD imposes a near-term mandatory wiring modification and inspection (plus, for some aircraft, a fuse change) on specified Learjet 45 serial numbers to eliminate wiring-to-hydraulic-line chafing that was linked to an engine-nacelle fire; operators pay for and schedule the work and must follow the Bombardier service instructions or FAA‑approved alternatives.**"}},"importantCases":[],"_links":{"self":"/api/acts/ad-lj45-8-engine-electrical-wire-bundles","history":"/api/acts/ad-lj45-8-engine-electrical-wire-bundles/history","analysis":"/api/acts/ad-lj45-8-engine-electrical-wire-bundles/analysis","conflicts":"/api/acts/ad-lj45-8-engine-electrical-wire-bundles/conflicts","importantCases":"/api/acts/ad-lj45-8-engine-electrical-wire-bundles/important-cases","documents":"/api/acts/ad-lj45-8-engine-electrical-wire-bundles/documents"}}