[Federal Register Volume 66, Number 222 (Friday, November 16, 2001)]
[Rules and Regulations]
[Pages 57653-57655]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-28688]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NE-53-AD; Amendment 39-12506; AD 2001-23-09]
RIN 2120-AA64


Airworthiness Directives; Honeywell International Inc. TFE731-2, 
-3, and -4 Series Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment supersedes two existing airworthiness 
directives (ADs), applicable to Honeywell International Inc. (formerly 
AlliedSignal Inc. and Garrett Turbine Engine Co.) TFE731-2, -3, and -4 
series turbofan engines. Those AD's currently require removing certain 
fan rotor discs from service in accordance with a drawdown schedule, 
and establishing new fan rotor disc life limits. This amendment 
requires stricter life limits for certain fan rotor discs. This 
amendment is prompted by the availability of an improved fan rotor disc 
and by a reduction in the probability of fan rotor disc failure by 
terminating the life of the older, high-stressed, fan rotor disc. The 
actions specified in this AD are intended to prevent failure of the fan 
rotor disc due to fatigue cracking in the dovetail slots, which could 
result in in-flight engine shutdown, uncontained engine failure, and 
damage to the airplane.

DATES: Effective date December 21, 2001.

ADDRESSES: The service information referenced in this AD may be 
obtained from Honeywell Engines and Systems

[[Page 57654]]

(formerly AlliedSignal Inc. and Garrett Turbine Engine Co.) Technical 
Publications and Distribution, M/S 2101-201, P.O. Box 52170, Phoenix, 
AZ 85072-2170; telephone: (602) 365-2493 (General Aviation), (602) 365-
5535 (Commercial Aviation), fax: (602) 365-5577 (General Aviation), 
(602) 365-2832 (Commercial Aviation). This information may be examined, 
by appointment, at the Federal Aviation Administration (FAA), New 
England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Joseph Costa, Aerospace Engineer, Los 
Angeles Aircraft Certification Office, FAA, Transport Airplane 
Directorate, 3960 Paramount Blvd., Lakewood, CA 90712-4137; telephone: 
(562) 627-5246; fax: (562) 627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 86-11-05, 
Amendment 39-5325 (51 FR 2025, June 4, 1986), and AD 96-18-13, 
Amendment 39-9737 (61 FR 47806, September 11, 1996), which are 
applicable to Honeywell International Inc. (formerly AlliedSignal Inc. 
and Garrett Turbine Engine Co.) TFE731-2, -3, and -4 series turbofan 
engines, was published in the Federal Register on May 2, 2001 (66 FR 
21896). That action proposed to require replacing fan rotor discs part 
numbers (P/N's) 3072162-All, 3072816-All, 3073436-All, 3073539-All, and 
3074529-All (where All denotes all dash numbers).

Comments

    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.

Economic Analysis

    There are approximately 1,400 engines with affected discs in the 
worldwide fleet. The FAA estimates that 1,100 engines installed on 
aircraft of U.S. registry would be affected by this AD. The FAA also 
estimates that it would take approximately one work hour per engine to 
accomplish this action during a normally scheduled fan rotor disc 
removal period, and approximately six work hours per engine to 
accomplish this action during an unscheduled fan rotor disc removal 
period, and that the average labor rate is $60 per work hour. Required 
parts would cost approximately $20,400 per engine. Based on these 
figures, the total cost effect of this AD on U.S. operators is 
estimated to be $22,509,000.

Regulatory Analysis

    This final rule does not have federalism implications, as defined 
in Executive Order 13132, because it would not have a substantial 
direct effect 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. Accordingly, 
the FAA has not consulted with state authorities prior to publication 
of this final rule.
    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 the DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 
will not have a significant economic effect, 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 by contacting the Rules Docket at the location provided 
under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Amendment 39-5325 (51 FR 
2025, June 4, 1986), and Amendment 39-9737 (61 FR 47806, September 11, 
1996) and by adding a new airworthiness directive, Amendment 39-12506, 
to read as follows:

2001-23-09  Honeywell International Inc.: Amendment 39-12506. Docket 
2000-NE-53-AD. Supersedes AD 86-11-05, Amendment 39-5325 and AD 96-
18-13, Amendment 39-9737.

Applicability

    This airworthiness directive (AD) is applicable to Honeywell 
International Inc. (formerly AlliedSignal Inc. and Garrett Turbine 
Engine Co.) TFE731-2, -3, and -4 series turbofan engines, with fan 
rotor discs part numbers (P/N's) 3072162-All, 3072816-All, 3073436-
All, 3073539-All, and 3074529-All (where All denotes all dash 
numbers). These engines are installed on, but not limited to, Avions 
Marcel Dassault Falcon 10, 50, and 100 series; Learjet 31, 35, 36, 
and 55 series; Lockheed-Georgia 1329-23 and -25 series; Israel 
Aircraft Industries 1124 series and 1125 Westwind series; Cessna 
Model 650, Citations III, VI, and VII; Raytheon British Aerospace 
HS-125 series; and Sabreliner NA-265-65 airplanes.

    Note 1: This 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 the performance 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

    Compliance with this AD is required as indicated, unless already 
done.
    To prevent failure of the fan rotor disc due to fatigue cracking 
in the dovetail slots, which could result in in-flight engine 
shutdown, uncontained engine failure, and damage to the airplane, do 
the following:
    (a) Remove fan rotor discs P/N's 3072162-All, 3072816-All, 
3073436-All, 3073539-All, and 3074529-All (where All denotes all 
dash numbers), and replace with serviceable fan rotor discs at next 
access to the fan rotor disc, at the next scheduled fan rotor disc 
inspection, or prior to December 31, 2002, whichever occurs 
earliest. Fan rotor disc replacement information is available in 
Honeywell International Inc. Alert Service Bulletin TFE731-A72-3668, 
dated October 25, 2000.

Definitions

    (b) For the purpose of this AD, the following definitions apply:
    (1) Access to the fan rotor disc is whenever the fan shaft is 
unstretched.
    (2) A serviceable disc is a disc that does not have a P/N listed 
in this AD.

Alternative Methods of Compliance

    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Los Angeles Aircraft Certification 
Office (LAACO). Operators must submit their request through an 
appropriate FAA Principal Maintenance Inspector, who may add 
comments and then send it to the Manager, LAACO.


[[Page 57655]]


    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the LAACO.

Special Flight Permits

    (d) Special flight permits may be issued in accordance 
Secs. 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.

Effective Date

    (e) This amendment becomes effective on December 21, 2001.

    Issued in Burlington, Massachusetts, on November 7, 2001.
Donald E. Plouffe,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 01-28688 Filed 11-15-01; 8:45 am]
BILLING CODE 4910-13-P