[Federal Register Volume 69, Number 115 (Wednesday, June 16, 2004)]
[Proposed Rules]
[Pages 33590-33592]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-13563]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-18019; Directorate Identifier 2003-NE-65-AD]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Honeywell International Inc. (formerly AlliedSignal Inc. and 
Garrett Turbine Engine Co.) TFE731-2 and -3 series turbofan engines 
with certain part number (P/N) low pressure turbine (LPT) stage 1 disks 
installed. This proposed AD would require for TFE731-2 and -2C series 
engines, initial and repetitive measurements and calculations to 
determine acceptance, and adjustment or replacement if necessary, of 
the LPT stage 1 nozzle assembly. This proposed AD would also require 
for TFE731-3, -3A, -3AR, -3B, -3BR, and -3R series engines, replacement 
of LPT stage 1 disks with serviceable disks. This proposed AD also 
allows replacement of the LPT stage 1 disk with a disk having a part 
number not listed in the proposed AD as optional terminating action to 
the repetitive actions. This proposal results from a report of an 
uncontained failure of the LPT stage 1 disk installed in a TFE731-3-1H 
turbofan engine. We are proposing this AD to prevent additional 
uncontained failure of the LPT stage 1 disk, and possible damage to the 
airplane.

DATES: We must receive any comments on this proposed AD by August 16, 
2004.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    You can get the service information identified in this proposed AD 
from Honeywell Engines and Systems (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).
    You may examine the comments on this proposed AD in the AD docket 
on the Internet at http://dms.dot.gov.

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:

Docket Management System (DMS)

    We have implemented new procedures for maintaining AD dockets 
electronically. As of May 17, 2004, we posted new AD actions on the DMS 
and assigned a DMS docket number. We track each action and assign a 
corresponding Directorate identifier. The DMS docket No. is in the form 
``Docket No. FAA-200X-XXXXX.'' Each DMS docket also lists the 
Directorate identifier (``Old Docket Number'') as a cross-reference for 
searching purposes.

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2004-18019; 
Directorate Identifier 2003-NE-65-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of the 
DMS web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78) or you 
may visit http://dms.dot.gov.
    We are reviewing the writing style we currently use in regulatory 
documents. We are interested in your comments on whether the style of 
this document is clear, and your suggestions to improve the clarity of 
our communications that affect you. You can get more information about 
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.

Examining the AD Docket

    You may examine the docket that contains the proposal, any comments 
received, and any final disposition in person at the DMS Docket Offices 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Office (telephone (800) 647-5227) is located on 
the plaza level of the Department of Transportation Nassif Building at 
the street address stated in ADDRESSES. Comments will be available in 
the AD docket shortly after the DMS receives them.

Discussion

    In June of 2003, we became aware of a report of a TFE731-3-1H 
turbofan engine that experienced an uncontained failure of LPT stage 1 
disk, P/N 3072351-5. Analysis by the manufacturer revealed that the 
disk, which only had 107 hours of operation accumulated since new, 
failed due to vibration-induced high-cycle-fatigue (HCF) cracking in 
the web area of the disk. Analysis and testing of these vibrations have 
revealed that the disk design is sensitive to significant nozzle 
throat-area variations such as those caused by inappropriate 
maintenance of the vanes of the LPT stage 1 nozzle assembly. Two other 
uncontained disk failures involving TFE731-3 series

[[Page 33591]]

engines occurred over the past 16 years and were considered at the time 
to have been caused by inappropriate maintenance practices performed on 
the LPT stage 1 nozzle assembly. We have determined that similarly 
designed LPT stage 1 disks, P/Ns 3072070-All, 3072351-All, 3073013-All, 
3073113-All, 3073497-All, and 3074103-All, (where All denotes all dash 
numbers), are sensitive for the same reasons described for disk P/N 
3072351-5. This condition, if not corrected, could result in 
uncontained failure of the LPT stage 1 disk, and possible damage to the 
airplane.

Relevant Service Information

    We have reviewed and approved the technical contents of Honeywell 
International Inc. Service Bulletin No. TFE731-72-3369RWK, Revision 6, 
dated June 26, 2002, that describes procedures for inspection, 
measurement and adjustment, or replacement if necessary, of the LPT 
stage 1 nozzle assembly. These procedures reduce the potential for 
vibration-induced HCF cracking in the web area of the disk.

Differences Between the Proposed AD and the Manufacturer's Service 
Information

    Although Honeywell International Inc. SB No. TFE731-72-3369RWK, 
Revision 6, dated June 26, 2002, requires the inspections, measurements 
and adjustments, and replacements of the LPT stage 1 nozzle assembly to 
be done by certain approved repair stations, this proposed AD allows 
the actions to be done by any repair station certificated to perform 
the repair work.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. Therefore, we are proposing this AD, which 
would require:

     For TFE731-2 and -2C series engines with LPT stage 1 
disk, P/Ns 3072070-All, or 3073013-All, (where All denotes all dash 
numbers) installed, initial and repetitive measurements and 
calculations to determine the acceptance, and adjustment or 
replacement if necessary of the LPT stage 1 nozzle assembly. These 
actions are to be done at the next major periodic inspection (MPI) 
or at next access to the LPT stage 1 nozzle assembly, whichever 
occurs first, but not to exceed 2,200 hours time-in-service (TIS) 
since the last LPT stage 1 nozzle assembly inspection.
     For TFE731-3, -3A, -3AR, -3B, -3BR, and -3R series 
engines with LPT stage 1 disk, P/N 3072351-All, 3073113-All, 
3073497-All, or 3074103-All, installed, replacement of the LPT stage 
1 disk with a serviceable disk, at next major periodic inspection or 
at next access to the LPT stage 1 nozzle assembly, but not to exceed 
1,500 hours time-in-service since last inspection, or before 
December 31, 2011, or at disk life limit, whichever occurs first.
     As optional terminating action to the repetitive 
actions of the proposed AD, replacement of the LPT stage 1 disk with 
a serviceable disk.
     For the purposes of this proposed AD, a serviceable LPT 
stage 1 disk is a disk having a part number not listed in this 
proposed AD.

    The proposed AD would require you to use the service information 
described previously to perform these actions.

Costs of Compliance

    There are about 5,462 TFE731-2 and -3 series turbofan engines of 
the affected design in the worldwide fleet. We estimate that 3,572 
engines installed on airplanes of U.S. registry would be affected by 
this proposed AD. We also estimate that it would take about 8 work 
hours per engine to perform the proposed measurements and calculations 
during MPI, and about 2 work hours per engine to replace the disk 
during MPI. The average labor rate is $65 per work hour. Required 
replacement parts would cost about $30,000 per engine. We expect about 
1,900 engines to have the LPT stage 1 disk replaced. Based on these 
figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $58,151,000.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed 
regulation:
    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. Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared a summary of the costs to comply with this proposal and 
placed it in the AD Docket. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive:

Honeywell International Inc.: Docket No. FAA-2004-18019; Directorate 
Identifier 2003-NE-65-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by August 16, 
2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Honeywell International Inc. (formerly 
AlliedSignal Inc. and Garrett Turbine Engine Co.) TFE731-2 and -2C 
series, and TFE731-3, -3A, -3AR, -3B, -3BR, and -3R series turbofan 
engines, with low pressure turbine (LPT) stage 1 disks, part numbers 
(P/Ns) 3072070-All, 3072351-All, 3073013-All, 3073113-All, 3073497-
All, and 3074103-All, (where All denotes all dash numbers), 
installed. These engines are installed on, but not limited to, the 
following airplanes:

Avions Marcel Dassault Falcon 10 and Mystere Falcon 50 series
Learjet 31, 35, 36, and 55 series
Lockheed-Georgia 1329-25 series
Israel Aircraft Industries 1124 series and 1125 Westwind series
Cessna Model 650, Citations III and VI
Raytheon British Aerospace HS-125 series
Sabreliner NA-265-65

Unsafe Condition

    (d) This AD results from a report of an uncontained failure of 
the LPT stage 1 disk installed in a TFE731-3-1H turbofan engine. We 
are issuing this AD to prevent uncontained failure of the LPT stage 
1 disk, and possible damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

Initial Inspection for TFE731-2 and -2C Series Engines

    (f) For TFE731-2 and -2C series engines with LPT stage 1 disk, 
P/N 3072070-All, or

[[Page 33592]]

3073013-All, installed, at the next major periodic inspection (MPI) 
or at next access to the LPT stage 1 nozzle assembly, after the 
effective date of this AD, whichever occurs first, but not to exceed 
2,200 hours time-in-service (TIS) since the last LPT stage 1 nozzle 
assembly inspection, do the following:
    (1) Measure and determine the acceptance of the LPT stage 1 
nozzle assembly using paragraphs 2.A.(3) through 2.A.(5) of 
Honeywell International Inc. Service Bulletin (SB) No. TFE731-72-
3369RWK, Revision 6, dated June 26, 2002; and
    (2) If necessary, adjust the LPT stage 1 nozzle assembly using 
paragraph 2.B of Honeywell International Inc. SB No. TFE731-72-
3369RWK, Revision 6, dated June 26, 2002 or replace with a 
serviceable LPT stage 1 nozzle assembly.

Repetitive Inspections for TFE731-2 and -2C Series Engines

    (g) Thereafter, for TFE731-2 and -2C series engines, at every 
MPI, but not to exceed 2,200 hours time-in-service since the last 
LPT stage 1 nozzle assembly inspection, do the following:
    (1) Measure and determine the acceptance of the LPT stage 1 
nozzle assembly using paragraph 2.A.(3) through 2.A.(5) of Honeywell 
International Inc. SB No. TFE731-72-3369RWK, Revision 6, dated June 
26, 2002; and
    (2) If necessary, adjust the LPT stage 1 nozzle assembly using 
paragraph 2.B of Honeywell International Inc. SB No. TFE731-72-
3369RWK, Revision 6, dated June 26, 2002 or replace with a 
serviceable LPT stage 1 nozzle assembly.

Disk Replacement for TFE731-3, -3A, -3AR, -3B, -3BR, and -3R Series 
Engines

    (h) For TFE731-3, -3A, -3AR, -3B, -3BR, and -3R series engines 
with LPT stage 1 disk, P/N 3072351-All, 3073113-All, 3073497-All, or 
3074103-All, installed, replace the LPT stage 1 disk with a 
serviceable disk, at next MPI or at next access to the LPT stage 1 
nozzle assembly, after the effective date of this AD, or before 
December 31, 2011, or at disk life limit, whichever occurs first.

TFE731-3B and -3BR Series Engines

    (i) For TFE731-3B and -3BR series engines, no replacement LPT 
stage 1 disk is available for disk P/N 3073497-All. Conversion from 
the TFE731-3B and -3BR series engines to the TFE731-3C series engine 
changes the turbine rotor configuration to allow installation of a 
serviceable LPT stage 1 disk.

Optional Terminating Action

    (j) As optional terminating action to the repetitive inspections 
required by this AD, replace the applicable LPT stage 1 disk with a 
serviceable LPT stage 1 disk.

Definitions

    (k) For the purposes of this AD:
    (1) Next access to the LPT stage 1 nozzle assembly is defined as 
when the low-pressure tie-shaft is unstretched.
    (2) A serviceable LPT stage 1 disk is defined as a disk having a 
part number not listed in this AD.
    (3) A serviceable LPT stage 1 nozzle assembly is defined as an 
LPT stage 1 nozzle assembly that passes the acceptance referenced in 
paragraph (f)(1) or (g)(1) of this AD.

Additional Information

    (l) For additional information regarding the training and 
tooling recommended to perform the inspection and adjustment of the 
LPT stage 1 nozzle assembly, contact Honeywell Engines, Systems & 
Services, Customer Support Center, M/S 26-06/2102-323, P.O. Box 
29003, Phoenix, AZ 85038-9003, Telephone: (Domestic) 1-800-601-3099 
(International) 1-602-365-3099, FAX: 1-602-365-3343.

Alternative Methods of Compliance

    (m) The Manager, Los Angeles Aircraft Certification Office, has 
the authority to approve alternative methods of compliance for this 
AD if requested using the procedures found in 14 CFR 39.19.

Material Incorporated by Reference

    (n) None.

Related Information

    (o) None.

    Issued in Burlington, Massachusetts, on June 4, 2004.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 04-13563 Filed 6-15-04; 8:45 am]
BILLING CODE 4910-13-U