AD 86-05-05 R1

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.