# AD 86-05-05 R1: Battery Vent System

- Type: Airworthiness directive
- Status: Current
- Products: Learjet 23, 24, 24A, 24B, 24B-A, 24C, 24D, 24D-A, 24E, 24F, 24F-A, 25 and 11 more
- Effective: January 19, 1988
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small/large airplane
- Amendment: 39-5792
- Registered aircraft: 286 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/8686D7A58109976786256988007607E0.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/86-05-05-R1

## The airworthiness directive

86-05-05 R1 GATES LEARJET CORPORATION: Amendment 39-5248 as amended by Amendment 39-5792. Applies to the following Gates Learjet models and serial numbers, equipped with a "flow through" battery vent system with the inlet located on the bottom (belly) of the airplane:

MODEL SERIAL NUMBERS 23 series 003 thru 099 24, 24A, 24B, 24B-A, 100 thru 357 24C, 24D, 24D-A,

24E, 24F, 24F-A

25, 25A, 25B, 25C, 25D, 25F 003 thru 061; 066 thru 373 28 001 thru 005 29 001 thru 004 35,35A 001 thru 570; 589 thru 600 36, 36A 001 thru 053; 055

Compliance required as indicated, unless previously accomplished.

To eliminate the potential for a fire and explosion within the battery, caused by leaking fuel entering the battery vent, accomplish the following within the next 200 flight hours:

A. Relocate the battery inlet vent in accordance with instructions contained in Gates Learjet Corporation Service Bulletin (SB) 23/24/25-334B, dated February 19, 1987, for Models 23, 24, and 25 series airplanes; SB 28/29-24-5A, dated October 7, 1985, for Models 28 and 29 series airplanes; or SB 35/36-24-10, dated July 18, 1987, for Models 35 and 36 series airplanes; or later FAA-approved revisions.

B. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

C. Alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety may be used when approved by the Manager, Wichita Aircraft Certification Office, FAA, Central Region.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Gates Learjet Corporation, P.O. Box 7707, Wichita, Kansas 67277. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or FAA, Central Region,Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid- Continent Airport, Wichita, Kansas

Amendment 39-5248 became effective April 11, 1986.

This amendment, 39-5792, becomes effective January 19, 1988.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A10CE](https://openairdocs.org/tcds/A10CE): Learjet Inc.; names 22 of 29 models: 24, 24A, 24B, 24B-A, 24C, 24D, 24D-A, 24E…
- [TCDS A5CE](https://openairdocs.org/tcds/A5CE): Learjet Inc.; names 1 of 1 models: 23

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 286 (286 by airframe model, 0 by engine model)
- Makers: Gates Learjet 156, Gates Lear Jet 80, Learjet 50

Models with the most aircraft:

- [Gates Learjet 35A](https://openairdocs.org/model/gates-learjet-35a): 135 aircraft (airframe model)
- [Learjet 35A](https://openairdocs.org/model/learjet-35a): 24 aircraft (airframe model)
- [Gates Lear Jet 36A](https://openairdocs.org/model/gates-lear-jet-36a): 21 aircraft (airframe model)
- [Gates Learjet 25D](https://openairdocs.org/model/gates-learjet-25d): 20 aircraft (airframe model)
- [Gates Lear Jet 35](https://openairdocs.org/model/gates-lear-jet-35): 16 aircraft (airframe model)
- [Gates Lear Jet 36](https://openairdocs.org/model/gates-lear-jet-36): 13 aircraft (airframe model)
- [Gates Lear Jet 25B](https://openairdocs.org/model/gates-lear-jet-25b): 12 aircraft (airframe model)
- [Learjet 24](https://openairdocs.org/model/learjet-24): 7 aircraft (airframe model)
- [Gates Lear Jet 24D](https://openairdocs.org/model/gates-lear-jet-24d): 7 aircraft (airframe model)
- [Learjet 23](https://openairdocs.org/model/learjet-23): 6 aircraft (airframe model)
- [Learjet 24D](https://openairdocs.org/model/learjet-24d): 4 aircraft (airframe model)
- [Gates Lear Jet 24F](https://openairdocs.org/model/gates-lear-jet-24f): 4 aircraft (airframe model)
- [Learjet 24B](https://openairdocs.org/model/learjet-24b): 3 aircraft (airframe model)
- [Gates Lear Jet 28](https://openairdocs.org/model/gates-lear-jet-28): 3 aircraft (airframe model)
- [Learjet 24A](https://openairdocs.org/model/learjet-24a): 2 aircraft (airframe model)
- [Gates Lear Jet 24E](https://openairdocs.org/model/gates-lear-jet-24e): 2 aircraft (airframe model)
- [Learjet 25](https://openairdocs.org/model/learjet-25): 2 aircraft (airframe model)
- [Gates Lear Jet 25](https://openairdocs.org/model/gates-lear-jet-25): 1 aircraft (airframe model)
- [Gates Lear Jet 25C](https://openairdocs.org/model/gates-lear-jet-25c): 1 aircraft (airframe model)
- [Learjet 25D](https://openairdocs.org/model/learjet-25d): 1 aircraft (airframe model)

All 23 models: https://openairdocs.org/ad/86-05-05-R1/models.md
Every aircraft: https://openairdocs.org/ad/86-05-05-R1/aircraft.md

Its text cites no advisory circulars or STCs.

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