AD 88-17-01

88-17-01 ALLISON GAS TURBINE DIVISION, GENERAL MOTORS CORPORATION (ALLISON): Amendment 39-6092. Final copy of Priority Letter AD 88-17-01 issued August 15, 1988. Applicability: Allison Model 250-B17, -C20, -C20R, and -C30 series engines, incorporating Bendix gas producer fuel controls listed in the attached appendix, installed in aircraft certificated in any category. Compliance: Required as indicated, unless already accomplished. To prevent possible engine over-temperature, loss of throttle response, or unscheduled power increase accomplish the following: (a) Remove from service within the next ten (10) operating hours after the effective date of this AD, the affected Bendix gas producer fuel controls listed by part number and serial number in the attached appendix and replace with a serviceable part. NOTES: (1) Out-of-service affected Bendix gas producer fuel controls, listed by part number and serial number in the attached appendix, may be returned to serviceupon the incorporation of Allison Alert Commercial Engine Bulletin (CEB) titled "Engine, Fuel and Control, Inspection of Certain Bendix Fuel Control Bellows Assemblies", dated August 1, 1988, with applicability as follows:

ENGINE MODEL BULLETIN NUMBER 250-C20 Series CEB-A-1272 250-B17 Series TP CEB-A-1231 250-C30 Series CEB-A-73-3042 250-C20R Series CEB-A-73-4008

(2) Those affected Bendix gas producer fuel controls incorporating the above-cited Allison Alert CEB are identified by a green mark on the cylinder portion of the self-locking cap nut and either the letter "A" or the letter "B" in the "LESS ISSUE" block of the data plate. (b) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where this AD can be accomplished. (c) Upon request, an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Chicago Aircraft Certification Office, Federal Aviation Administration, 2300 East Devon Avenue, Des Plaines, Illinois 60018. (d) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, the Manager, Chicago Aircraft Certification Office, may adjust the compliance time specified in this AD. Allison Alert CEB titled "Engine, Fuel and Control, Inspection of Certain Bendix Fuel Control Bellows Assemblies", dated August 1, 1988, identified and described in this document, is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request to Allison Gas Turbine Division, General Motors Corporation, P.O. Box 420, Indianapolis, Indiana 46206-0420. This document may also be examined at the Office of the Assistant Chief Council, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, Room 311, Rules Docket Number 88-ANE-32, between the hours of 8:00 a.m. and 4:30 p.m., Monday through Friday, except federal holidays. This amendment (39-6092, AD 88-17-01) becomes effective March 1, 1989, as to all persons except those persons to whom it was made immediately effective by individual Priority Letter AD 88-17-01 issued August 15, 1988, which contained this amendment.

APPENDIX AD 88-17-01

Bendix Fuel Controls:

Bendix Part No.: 2524644-26 (Allison 23033917)

Serial No.: 87241174 87490092 88041524 88090122

87370001 88041515 88090107 88090124

* 87430041 88041516 88090110 88090125

87430042 88041517 88090112 88090126

* 87430044 88041518 88090114 88090128

87430045 88041519 88090116 88090129

87490081 88041520 88090118 88090130

87490082 88041521 88090119 88090131

87490083 88041522 88090120

87490084 88041523 88090121

Bendix Part No.: 2524654-23 (Allison 23036660)

Serial No.: 87251235

87460078

Bendix Part No.: 2524886-10 (Allison 23033919)

Serial No.: 87430052 87430055 87490102

87430053 87490101 87490104

Bendix Part No: 2524922-6 (Allison 23033849)

Serial No.: 87370010

88090143

88090144

Bendix Part No.: 2524957-3 (Allison 23030614)

Serial No.: 84250105

Bendix Part No.: 2524986-2 (Allison 23038954)

Serial No.: 87490095

87490098

Bendix Part No.: 2549032-2 (Allison 23037275)

Serial No.: 87430056 87430063 88090154 88090163

87430057 87430065 88090155 88090165

87430059 88090147 88090156 88090166

87430060 88090149 88090157 88130236

87430061 88090151 88090158 88130249

87430062 88090152 88090160 88130250

*These Serial Nos. corrected from Priority Letter AD 88-17-01 by this Final Rule.