[Federal Register Volume 67, Number 33 (Tuesday, February 19, 2002)]
[Proposed Rules]
[Pages 7318-7319]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-3877]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-53-AD]
RIN 2120-AA64


Airworthiness Directives; Honeywell International Inc. TPE331 
Series Turboprop and TSE331-3U Series Turboshaft Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The Federal Aviation Administration (FAA) proposes to adopt a 
new airworthiness directive (AD) that is applicable to Honeywell 
International Inc. (formerly AlliedSignal Inc., Garrett Engine 
Division, Garrett Turbine Engine Company, and AiResearch Manufacturing 
Company of Arizona) TPE331 series turboprop and model TSE331-3U series 
turboshaft engines. This proposal would require replacing second stage 
turbine stator assemblies, part numbers (P/N's) 894528-1, -2, -3, -5, -
6, -10, and -11, with serviceable turbine stator assemblies. This 
proposal is prompted by reports of six uncontained separations of the 
second stage turbine wheels. The actions specified by the proposed AD 
are intended to reduce fatigue damage of the second stage turbine 
stator inner seal support, rotating knife seal, and the second and 
third stage turbine wheels which may result in an uncontained rotor 
failure and damage to the aircraft.

DATES: Comments must be received by April 22, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 99-NE-53-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at 
this location, by appointment, between 8:00 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. Comments may also be sent via 
the Internet using the following address: ``[email protected]''. 
Comments sent via the Internet must contain the docket number in the 
subject line.
    The service information regarding the replacement and inspection of 
parts may be obtained from Honeywell Engines, Systems, and Services, 
Technical Data Distribution, M/S 2101-201, P.O. Box 52170, Phoenix, AZ 
85072-2170; telephone: (602) 365-2493 (General Aviation), (602) 365-
5535 (Commercial); fax: (602) 365-5577 (General Aviation and 
Commercial). This information may be examined at the FAA, New England 
Region, Office of the Regional Counsel, 12 New England Executive Park, 
Burlington, MA.

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

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this action may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 99-NE-53-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRM's

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, New England Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 99-NE-53-AD, 12 New England Executive Park, 
Burlington, MA 01803-5299.

Discussion

    There have been six reported uncontained separations of second 
stage turbine wheels associated with obstructed internal cooling holes 
or passages in the vanes of the second stage turbine stator. The FAA 
has determined that obstructed cooling holes in the second stage 
turbine stator will increase turbine cavity temperatures. These 
elevated temperatures reduce the fatigue endurance capability of the 
turbine stator components and could cause the seal assembly to separate 
from the stator housing, or the rotating knife edge seal to separate 
from the turbine rotor. The stator seal support, stator seal assembly, 
or the rotating knife edge seal may then contact and rub into the 
turbine rotor, potentially resulting in an uncontained turbine rotor 
separation. Elevated cavity temperatures may also cause a reduction in 
the fatigue life of the turbine rotor and may result in an uncontained 
turbine rotor separation. In addition, the FAA has approved an air flow 
inspection and re-identification procedure for the second stage stator 
assemblies, P/N 894528-10 and -11. The FAA has not approved an air flow 
inspection of the older configurations of second stage stator 
assemblies, P/Ns 894528-1, -2, -3, -5, and -6, due to the difficulty to 
maintain the dimensional integrity of the stator assembly's internal 
cooling passages after the final braze operation of the stator's inner 
seal support or after welding of the stator's vanes. The FAA has 
approved repair procedures for converting the older configuration of 
second stage turbine

[[Page 7319]]

stator assembly's inner seal support to a serviceable configuration. 
This condition, if not corrected, could result in increased fatigue 
damage of the second stage turbine stator inner seal support, rotating 
knife seal, and the second and third stage turbine wheels which may 
result in an uncontained rotor failure and damage to the aircraft.

FAA's Determination of an Unsafe Condition and Proposed Actions

    Since an unsafe condition has been identified that is likely to 
exist or develop on other Honeywell International Inc. TPE331 series 
turboprop and TSE331-3U turboshaft engines of the same type design, the 
proposed AD would require replacing the existing second stage turbine 
stator assemblies, P/N's 894528-1, -2, -3, -5, -6, -10, and -11, with 
serviceable assemblies.

Economic Effect

    There are approximately 4,700 engines of the affected design in the 
worldwide fleet. The FAA estimates that 2,350 engines installed on 
aircraft of U.S. registry would be affected by this proposed AD, that 
it would take approximately 4.0 work hours per engine to do the 
proposed actions, and that the average labor rate is $60 per work hour. 
Required replacement parts would cost approximately $8,000 per engine. 
Based on these figures, the total cost of the proposed AD on U.S. 
operators is estimated to be $14,958,000.
    This proposed 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 proposed rule.
    For the reasons discussed above, I certify that this 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) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action 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.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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 adding the following new 
airworthiness directive:

Honeywell International Inc.: Docket No. 99-NE-53-AD.

    Applicability: This airworthiness directive (AD) is applicable 
to Honeywell International Inc. (formerly AlliedSignal Inc., Garrett 
Engine Division, Garrett Turbine Engine Company, and AiResearch 
Manufacturing Company of Arizona) Model TPE331-1, -2, -2UA, -3U, -
3UW, -5, -5A, -5AB, -5B, -6, and -6A series turboprop and TSE331-3U 
Model turboshaft engines with second stage turbine stator 
assemblies, part numbers (P/N's) 894528-1, -2, -3, -5, -6, -10, and 
-11. These engines are installed on, but not limited to Ayres S-2R 
series; Beech 18 and 45 series and model JRB-6, 3N, 3NM, 3TM, and 
B100 airplanes; Construcciones Aeronauticas, S.A. (CASA) C-212; De 
Havilland DH104 series 7AXC (Dove); Dornier 228 series; Fairchild 
SA226 series (Swearingen Merlin and Metro series); Grumman American 
G-164 series; Mitsubishi MU-2 and MU-2B series; Pilatus PC-6 series 
(Fairchild Porter and Peacemaker); Prop-Jets, Inc. Model 400; 
Rockwell Commander S2-R; Schweizer G-164 series; Shorts Brothers and 
Harland, Ltd. SC7 (Skyvan); and Twin Commander 680 and 690 series 
(Jetprop Commander) airplanes; and Sikorsky S-55 series (Helitec 
Corp. S55T) helicopters.

    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 reduce fatigue damage of the second stage turbine stator 
inner seal support, rotating knife seal, and the second and third 
stage turbine wheels which may result in an uncontained rotor 
failure and damage to the aircraft, do the following:
    (a) Replace second stage turbine stator assemblies, P/N's 
894528-1, -2, -3, -5, -6, -10, and -11, with a new or reworked 
second stage turbine stator assembly at the next removal of the 
second stage turbine stator assembly from the engine or at the next 
turbine section inspection, but do not exceed 3,100 engine operating 
hours since last turbine section inspection. Information for 
replacing second stage turbine stator assemblies is available in 
Honeywell International Inc. Alert Service Bulletin (ASB) TPE331-
A72-2082 dated May 16, 2001. Information for reworking second stage 
turbine stator assemblies is available in Honeywell International 
Inc. SB TPE331-72-2085RWK dated May 16, 2001.
    (b) After the effective date of this AD, do not install any 
second stage turbine stator assembly 
P/N's 894528-1, -2, -3, -5, -6, -10, and -11.

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.

    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 aircraft to a location where the 
requirements of this AD can be done.

    Issued in Burlington, Massachusetts, on February 12, 2002.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 02-3877 Filed 2-15-02; 8:45 am]
BILLING CODE 4910-13-U