[Federal Register Volume 63, Number 214 (Thursday, November 5, 1998)]
[Rules and Regulations]
[Pages 59699-59701]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-29602]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-ANE-60-AD; Amendment 39-10870; AD 98-23-06]
RIN 2120-AA64
Airworthiness Directives; General Electric Aircraft Engines CJ610
Turbojet and CF700 Series Turbofan Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to General Electric Aircraft Engines (GEAE) CJ610 series
turbojet and CF700 series turbofan engines. This action requires
operators to remove and replace with serviceable parts unapproved
combustion liner assemblies prior to further flight. This amendment is
prompted by findings that unapproved combustion liner assemblies are
installed on the affected engines. The actions specified in this AD are
intended to prevent combustor
[[Page 59700]]
liner cracking at multiple locations, progressing to liner fragmenting
and combustor casing burnthrough, which could result in an engine fire.
DATES: Effective November 20, 1998.
Comments for inclusion in the Rules Docket must be received on or
before January 4, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), New England Region, Office of the Regional
Counsel, Attention: Rules Docket No. 98-ANE-60-AD, 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.
FOR FURTHER INFORMATION CONTACT: Eugene Triozzi, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803-5299; telephone (781)
238-7148, fax (781) 238-7199.
SUPPLEMENTARY INFORMATION: The Federal Aviation Administration has
received reports of premature cracking of unapproved combustor liner
assemblies, part number (P/N) 6008T94G03, installed on General Electric
Aircraft Engines (GEAE) CJ610 series turbojet and CF700 series turbofan
engines. The investigation revealed that combustor liners were repaired
using unapproved inner and outer shells manufactured using a
substituted material, and with cooling slots, dilution holes, and other
geometric features that do not conform to approved drawing
requirements, resulting in increased stress levels at these features.
The substituted material or the increased stress levels or both can
result in reduced combustor life. In addition, because the potential
crack origin sites occur at multiple locations surrounding the
combustor, including liner cooling slots and dilution holes, adjacent
cracks may combine, resulting in liner holes and hot gas discharge from
the combustor. Analyses supported by inspections of parts have revealed
that unapproved liners will have an unknown service life that could be
significantly lower than the inspection interval requirements for
approved combustor liners. The FAA has identified 38 combustor liners,
identified by serial number (S/N), known to have been repaired using
inner or outer shells manufactured by an unknown manufacturer using
unknown processes and materials. The FAA has also identified additional
combustor liners, with unknown S/N markings, that were repaired in the
same way, by a particular certificated repair station. This condition,
if not corrected, could result in combustor liner cracking at multiple
locations, progressing to liner fragmenting and combustor casing
burnthrough, which could result in an engine fire.
Since an unsafe condition has been identified that is likely to
exist or develop on other engines of the same type design, this AD is
being issued to prevent combustor liner failure. This AD requires
removal and replacement of unapproved combustion liner assemblies with
serviceable parts prior to further flight.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the 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 that
summarizes each FAA-public contact concerned with the substance of
thisAD 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 98-ANE-60-AD.'' The postcard will be date stamped and
returned to the commenter.
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.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and is not a ``significant regulatory action''
under Executive Order 12866. It has been determined further that this
action involves an emergency regulation under DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979). If it is determined
that this emergency regulation otherwise would be significant under DOT
Regulatory Policies and Procedures, a final regulatory evaluation will
be prepared and placed in the Rules Docket. A copy of it, if filed, 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, 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 adding the following new
airworthiness directive:
98-23-06 General Electric Aircraft Engines: Amendment 39-10870.
Docket 98-ANE-60-AD.
Applicability: General Electric Aircraft Engines (GEAE) CJ610
series turbojet and CF700 series turbofan engines, with combustor
liner assemblies, part number (P/N) 6008T94G03, identified by serial
number (S/N) or otherwise specified in Appendix 1 of this AD,
installed. These engines are installed on but not limited to the
following aircraft: Dassault-Aviation Fan Jet Falcon 20 series,
Sabreliner NA265 series, Learjet 20
[[Page 59701]]
series, Israel Aircraft Industries Westwind series, Hansa Jet, Aero
Commander Jet Commander.
Appendix 1.--Serial Number Combustion Liners (Sorted Alphanumerically)
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1763...................................... GGM82
181....................................... GGM830
1939...................................... GGMB7019
318-1..................................... GGMH2135
318-2..................................... GGMM1218
35........................................ GKAPL77
497....................................... OG2250
564....................................... ST000891
900206.................................... ST00247
910205.................................... ST00276
GGM00028.................................. ST00303
GGM00518.................................. ST00391
GGM00536.................................. ST00488
GGM00585.................................. ST00623
GGM00893.................................. ST00808
GGM59515.................................. ST00840
GGM59675.................................. ST00896
GGM59801.................................. ST01042
GGM60028.................................. ST01142
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Additional Liners, With Serial Number Markings Unknown
Any other serial number combustion liner, part number
6008T94G03, following repair or overhaul which included installation
of inner shell, P/N 5016T30G02, or installation of outer shell, P/N
6008T95G01, during the period from May 16, 1997, through February
13, 1998, and if approved for return to service by: The Jet Engine
Shop (also known as 3d Industries, or 3DI, or identified by
Certificate Number CRS J3DR866N), 4553 Keller Springs Road, Dallas,
Texas 75248.
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 (b) 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 combustor liner cracking at multiple locations,
progressing to liner fragmenting and combustor casing burnthrough,
which could result in an engine fire, accomplish the following:
(a) Prior to further flight, for any combustor liner identified
by serial number (S/N), or otherwise identified in Appendix 1 of
this AD, remove from service and replace with a serviceable part.
(b) 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, Engine 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, Engine Certification Office.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this airworthiness directive,
if any, may be obtained from the Engine Certification Office.
(c) 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 record search requirements of this AD can be accomplished.
(d) This amendment becomes effective on November 20, 1998.
Issued in Burlington, Massachusetts, on October 30, 1998.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 98-29602 Filed 11-4-98; 8:45 am]
BILLING CODE 4910-13-U
