[Federal Register Volume 62, Number 147 (Thursday, July 31, 1997)]
[Proposed Rules]
[Pages 40985-40987]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-20193]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-ANE-13]
RIN 2120-AA64
Airworthiness Directives; AlliedSignal Inc. TPE331 Series
Turboprop and TSE331 Turboshaft Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to AlliedSignal Inc., (formerly
Garrett Engine Division, Garrett Turbine Engine Company and AiResearch
Manufacturing Company of Arizona) TPE331 series turboprop and TSE331
turboshaft engines. This proposal would require replacement or
radiographic inspection, and replacement , if necessary, of certain
third stage turbine stators with serviceable parts. This proposal is
prompted by a report of an outer band weld that cracked subsequent to a
radiographic inspection required by a previous AD. The actions
specified by the proposed AD are intended to prevent third stage
turbine wheel separation due to thermal fatigue cracking and shifting
of the third stage turbine stator, which could contact the third stage
turbine wheel and result in an uncontained engine failure and damage to
the aircraft.
DATES: Comments must be received by September 29, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), New England Region, Office of the Assistant Chief
Counsel, Attention: Rules Docket No. 97-ANE-13, 12 New England
Executive Park, Burlington, MA 01803-5299. Comments may also be sent
via the Internet using the following address: ``engineprop@faa.dot.gov''. Comments sent via the Internet must contain
the docket number in the subject line. Comments may be inspected at
this location between 8:00 a.m. and 4:30 p.m., Monday through Friday,
except Federal holidays.
The service information on AlliedSignal Service Bulletin No.
TPE331-A72-0861, Revision 2, dated April 23, 1997, referenced in the
proposed rule may be obtained from AlliedSignal Aerospace, Attn: Data
Distribution, M/S 64-3/2101-201, P.O. Box 29003, Phoenix, AZ 85038-
9003; telephone (602) 365-2493, fax (602) 365-5577. The service
information on National Flight Services Service Bulletin No. NF-TPE331-
A72-10961, dated April 28, 1997, referenced in the proposed rule may be
obtained from either National Flight Services, Inc. 10971 E. Airport
Services Road, Toledo Express Airport, Swanton, OH 43558; telephone
(419) 865-2311, fax (419) 867-4224, or http://www.natfs.com, or
National Flight Services of Arizona, Inc., 5170 W. Bethany Home Road,
Glendale, AZ 85301; telephone (602) 931-1143, fax (602) 931-7264. This
information may be examined at the FAA, New England Region, Office of
the Assistant Chief 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:
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 notice 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 97-ANE-13.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, New England Region, Office of the Assistant Chief Counsel,
Attention: Rules Docket No. 97-aNE-13, 12 New England Executive Park,
Burlington, MA 01803-5299.
Discussion
The Federal Aviation Administration (FAA) has received a report of
a third stage turbine stator outer band weld that cracked on an
AlliedSignal Inc. Model TPE331-5 turboprop engine. This weld, removed
from service in January 1996 after the crack was discovered during
turbine maintenance, had passed a one-time radiographic inspection for
unacceptable weld penetration and thermal fatigue cracking required by
AD 87-19-02. While AD 87-19-02 was
[[Page 40986]]
superseded by AD 93-05-09, the requirement for a one-time radiographic
inspection of the outer band weld for cracks was carried forward in to
AD 93-05-09. The FAA determined that cracking initiated due to
inadequate outer band butt weld penetration between the outer sheet
metal ring and the nozzle casting. The FAA also determined that some
radiographic films of unacceptable outer band welds may possibly have
been misread by AlliedSignal Inc. In addition, numerous radiographic
films are no longer on file at AlliedSignal Inc., and therefore
reexamination of radiographic films of other welds is impossible.
AlliedSignal Inc. no longer reads radiographic films; operators may use
radiographic inspection in accordance with this AD as an alternate
method of compliance with the radiographic inspection requirement of
paragraph (h) of AD 93-05-09. Inadequate weld penetration could lead to
fatigue cracking, shifting aft, and third stage turbine stator contact
with the third stage turbine rotor. This condition, if not corrected,
could result in third stage turbine wheel separation, which could
result in an uncontained engine failure and damage to the aircraft.
The FAA has reviewed and approved the technical contents of
National Flight Services Service Bulletin (SB) No. NF-TPE331-A72-10961,
dated April 28, 1997, that provides a list by serial number of third
stage turbine stators not affected by this AD and describes procedures
for the reinspection for unacceptable weld penetration and thermal
fatigue cracking in third stage turbine stators initially inspected by
AlliedSignal Inc.; and AlliedSignal Inc. SB No. TPE331-A72-0861,
Revision 2, dated April 23, 1997, that describes procedures for
replacing affected third stage turbine stators with redesigned
serviceable stators.
Since an unsafe condition has been identified that is likely to
exist or develop on other products of this same type design, the
proposed AD would require replacement of certain third stage turbine
stators or radiographic inspection, and replacement, if necessary, with
serviceable parts. The actions would be required to be accomplished in
accordance with the SBs described previously.
There are approximately 1,000 engines of the affected design in the
worldwide fleet. The FAA estimates that 700 engines installed on
aircraft of U.S. registry would be affected by this proposed AD. The
FAA estimates that 210 engines would require unscheduled replacement,
that it would take approximately 40 work hours per engine to accomplish
the proposed actions, and that the average labor rate is $60 per work
hour. Required parts would cost approximately $6,500 per engine.
Approximately 350 engines would require replacement during hot section
inspection, which would take approximately 2 work hours per engine,
with a parts cost of $6,500. Approximately 14 engines would require
unscheduled inspection, which would take approximately 50 work hours to
accomplish, with a parts cost of $1,500. Approximately 21 engines would
require inspection during hot section inspection, which would take
approximately 10 work hours to accomplish, with zero parts cost.
Approximately 35 engines would require unscheduled inspection and
replacement, which would take approximately 50 work hours to
accomplish, with a $6,500 parts cost. Approximately 70 engines would
require inspection and replacement during hot section inspection, which
would take approximately 10 work hours to accomplish, with a $5,000
parts cost. The FAA has been informed by AlliedSignal Inc. that they
will provide a redesigned third stage turbine stator assembly at a
special program price and will pay for the labor to install this
assembly. Based on these figures, without the special price program
from the manufacturer, the total cost impact of the proposed AD on U.S.
operators is estimated to be $4,986,100.
The regulations proposed herein would 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
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
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: AlliedSignal Inc.: Docket No. 97-ANE-13.
Applicability: AlliedSignal Inc., (formerly 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 turboprop and TSE331-3U
turboshaft engines with third stage turbine stators, Part Number (P/
N) 868379-3, except those engines with turbine stators listed by
Serial Number (S/N) in Table 1 of the National Flight Services
Service Bulletin (SB) No. NF-TPE331-A72-10961, dated April 28, 1997.
These engines are installed on but not limited to: Mitsubishi MU-2B
series (MU-2 series); Construcciones Aeronauticas, S.A. (CASA) C-212
series; Fairchild SA226 series (Swearingen Merlin and Metro series);
Prop-Jets, Inc. Model 400; Twin Commander 680 and 690 (Jetprop
Commander); Rockwell Commander S-2R; Shorts Brothers and Harland,
Ltd. SC7 (Skyvan); Dornier 228 series; Beech 18 and 45 series and
Models JRB-6, 3N, 3NM, 3TM, and B100; Pilatus PC-6 series (Fairchild
Porter and Peacemaker); De Havilland DH 104 series 7AXC (Dove);
Ayres S-2R series; Grumman American G-164 series; and Schweizer G-
164 series airplanes; and Sikorsky S-55 series (Helitec Corp. S55T)
helicopters.
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 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 (g) 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 third stage turbine wheel separation due to fatigue
cracking and
[[Page 40987]]
shifting of the third stage turbine stator, which could result in an
uncontained engine failure and damage to the aircraft, accomplish
the following:
(a) For engines with third stage turbine stators with S/Ns
listed in Table 1 of National Flight Services SB No. NF-TPE331-A72-
10961, dated April 28, 1997, no action is required.
(b) For engines with third stage turbine stators with S/Ns not
listed in Table 1 of National Flight Services SB No. NF-TPE331-A72-
10961, dated April 28, 1997, remove the unserviceable third stage
turbine stator assembly in accordance with the applicable engine
maintenance manual and the following schedule:
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Third stage turbine stator cycles in
service (cis) since radiographic
inspection in accordance with AD 87-19-02 Removal schedule
paragraph (b) or AD 93-05-09 paragraph (h)
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Unknown CIS since inspection.............. Remove within 600 CIS after
the effective date of this
AD, at next access, or
prior to March 31, 2002,
whichever occurs first.
2200 or more CIS since inspection......... Remove within 600 CIS after
the effective date of this
AD, at next access, or
prior to March 31, 2002,
whichever occurs first.
Less than 2200 CIS since inspection....... Remove prior to accumulating
2,800 CIS, at next access,
or prior to March 31, 2002,
whichever occurs first.
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(c) For the purpose of this AD, the next access to the third
stage stator assembly is defined as disassembly of the turbine
beyond the removal of the third stage rotor.
Note 2: This AD does not supersede AD 93-05-09. The removal
schedule in paragraph (b) of this AD does not affect the
requirements of AD 93-05-09.
(d) For the purpose of determining third stage turbine stator
removal under paragraph (b) of this AD, third stage turbine stator
hours time in service (TIS) may be converted to CIS since inspection
by multiplying by 1.5 the number of hours since radiographic
inspection in accordance with paragraph (b) of AD 87-19-02 or
paragraph (h) of AD 93-05-09.
(e) For third stage turbine stator assemblies removed in
accordance with paragraph (b) of this AD, accomplish either a
radiographic inspection for inadequate weld penetration and fatigue
cracking, and, if necessary, replace with a serviceable assembly in
accordance with the Accomplishment Instructions of National Flight
Services SB No. NF-TPE331-A72-10961, dated April 28, 1997; or
replace with a serviceable assembly in accordance with the
Accomplishment Instructions of AlliedSignal Inc. SB No. TPE331-A72-
0861, Revision 2, dated April 23, 1997. Accomplishing the
radiographic inspection required by this paragraph constitutes
compliance with the radiographic inspection requirement of paragraph
(h) of AD 93-05-09.
(f) 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. 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 3: Information concerning the existence of approved
alternative methods of compliance with this airworthiness directive,
if any, may be obtained from the Los Angeles Aircraft Certification
Office.
(g) 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 aircraft to a location where
the requirements of this AD can be accomplished.
Issued in Burlington, Massachusetts, on July 8, 1997.
Ronald L. Vavruska,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 97-20193 Filed 7-30-97; 8:45 am]
BILLING CODE 4910-13-U
