AD 98-17-01 R1

This amendment revises an existing airworthiness directive (AD), applicable to AlliedSignal Inc. TFE731 series turbofan engines, that currently requires installation of an improved flexible (flex) fuel tube. This amendment clarifies that installation of the improved flex fuel tube and that the use of a clamp on the original rigid fuel tube are optional for engines installed on Learjet 35, 36, and 55 series airplanes. This amendment is prompted by confusion from operators regarding the applicability of these Learjet engine installations. The actions specified by this AD are intended to prevent cracking of the fuel tube and the subsequent leakage of fuel on or around electrical components, which can cause an engine fire.

Final rule.

98-17-01 R1 ALLIEDSIGNAL INC: Amendment 39-11332. Docket 97-ANE-51-AD. Revises AD 98-17-01, Amendment 39-10703. Issued September 16, 1999.
Applicability: AlliedSignal Inc. (formerly Allied-Signal Aerospace Company, Garrett Engine Division and Garrett Turbine Engine Co.) TFE731-2, -3, and -4 series turbofan engines with fuel tubes, part numbers (P/Ns) 3071051-1, 3073729-1, or 3072886-1, installed. These engines are installed on but not limited to the following airplanes: Avions Marcel Dassault Falcon 10, 50, and 100 series; Cessna Model 650, Citation III, VI, and VII; Learjet 31 (M31) 35, 36 and 55 series, Raytheon British Aerospace HS-125 series; and Sabreliner NA-265-65.
NOTE 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that theperformance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
Compliance: Required as indicated, unless accomplished previously.
To prevent cracked fuel tubes and the subsequent leakage of fuel on and around electrical components, which can cause an engine fire, accomplish the following:
(a) Except for engines installed on Learjet 35, 36, and 55 airplanes, within 160 hours time-in-service (TIS) after the effective date of this AD, or prior to December 20, 1999, whichever occurs first, install an improved flexible fuel tube, as follows:
(1) For engines installed on Cessna airplanes, install inaccordance with the Accomplishment Instructions of AlliedSignal Inc. Alert Service Bulletin (ASB) No. TFE731-A73-3132, dated April 9, 1997.
(2) For engines installed on all other airplanes except for the Learjet 35, 36 and 55 series, install in accordance with the Accomplishment Instructions of AlliedSignal Inc. ASB No. TFE731-A73-3128, dated February 26, 1997.
(b) For engines installed on Learjet 35, 36, and 55, the improved flex tube and the clamp assembly installed on the original rigid fuel tube are optional. If the clamp assembly is used, install the clamp assembly in accordance with the Accomplishment Instructions of AlliedSignal Inc. SB No. TFE731-73-3107, Revision 4, dated April 20, 1994.
(c) An alternative method of compliance or adjustment of the initial compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles Aircraft Certification Office. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles Aircraft Certification Office.
NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles Aircraft Certification Office.
(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.
(e) The actions required by this AD shall be done in accordance with the following AlliedSignal Inc. service documents:

Document No.
Pages
Revision
Date
ASB TFE731-A73-3132
1-12
Original
April 9, 1997
Total pages: 12.

ASB TFE731-A73-3128
1-14
Original
February 26, 1997
Total pages: 14.

SB TFE731-73-3107
1-8
4
April 20, 1994
Total pages: 8.

(f) The incorporation by reference of AlliedSignal Inc. ASB TFE731-A73-3132, dated April 9, 1997, and ASB TFE731-A73-3128, dated February 26, 1997, was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of May 19, 1999.
(g) The incorporation by reference of AlliedSignal Inc. SB TFE731-73-3107, Revision 4, dated April 20, 1994, was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.
(h) Copies of these service documents may be obtained from AlliedSignal Aerospace, Attn: Data Distribution, M/S 64-3/2101-201, PO Box 29003, Phoenix, AZ 85038-9003; telephone (602) 365-2493, fax (602) 365-5577. Copies may be inspected at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.
(i) This amendment becomes effective on November 29, 1999.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by revising Airworthiness Directive (AD) 98-17-01, Amendment 39-10703 (63 FR 42691, August 11, 1998), which is applicable to AlliedSignal Inc. TFE731 series turbofan engines, was published in the Federal Register on April 19, 1999 (64 FR 19096). The action proposed to clarify that installation of the improved flexible (flex) fuel tube and that the use of a clamp on the original rigid fuel tube are optional for engines installed on Learjet 35, 36, and 55 series airplanes.
Since the issuance of AD 98-17-01, the FAA has received reports from operators expressing confusion as to the applicability of engines installed on Learjet 35, 36, and 55 series airplanes. That AD did not affect the AlliedSignal engine Model TFE731-2-2B and engine series TFE731-3A and -3AR installed on Learjet Models 35, 36, and 55 because starter generators are not used on these airplanes. In addition, forthis application, there have been no reported fuel line failures.
Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.
As this revision is merely a clarification, there is no additional economic impact on operators.
The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this action (1) is not a"significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: PART 39 - AIRWORTHINESS DIRECTIVES
Authority: 49 U.S.C. 106(g), 40113, 44701. 39.13 [Amended]
2. Section 39.13 is amended by removing Amendment 39-10703 (63 FR 42691, August 11, 1998), and by adding a new airworthiness directive, Amendment 39-11332, to read as follows:

REVISED AIRWORTHINESS DIRECTIVE

REGULATORY SUPPORT DIVISION P.O. BOX 26460 OKLAHOMA CITY, OKLAHOMA 73125-0460

U.S. Department of Transportation Federal Aviation Administration The following Airworthiness Directive issued by the Federal Aviation Administration in accordance with the provisions of Title 14 of the Code of Federal Regulations (14 CFR) part 39, applies to an aircraft model of which our records indicate you may be the registered owner. Airworthiness Directives affect aviation safety and are regulations which require immediate attention. You are cautioned that no person may operate an aircraft to which an Airworthiness Directive applies, except in accordance with the requirements of the Airworthiness Directive (reference 14 CFR part 39, subpart 39.3).