[Federal Register Volume 62, Number 235 (Monday, December 8, 1997)]
[Rules and Regulations]
[Pages 64513-64514]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-31862]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-ANE-21-AD; Amendment 39-10232; AD 97-25-08]
RIN 2120-AA64


Airworthiness Directives; General Electric Company CJ610 Series 
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 Company (GE) CJ610 series turbojet 
and CF700 series turbofan engines. This action requires removal from 
service of possibly defective turbine torque rings and compressor drive 
shafts which may have been manufactured from contaminated material; and 
replacement with serviceable parts. This amendment is prompted by a 
report of a cooling plate removed from a GE CT58 series engine that was 
found to have an iron-rich inclusion that came from a contaminated heat 
lot. Parts on GE CJ610 series and CF700 series engines which were 
manufactured from the same and similar heat lots may also be 
contaminated. The actions specified in this AD are intended to prevent 
turbine torque ring or compressor drive shaft failure due to a 
manufacturing defect, which could result in an uncontained engine 
failure.

DATES: Effective January 2, 1998. The incorporation by reference of 
certain publications listed in the regulations is approved by the 
Director of the Federal Register as of January 2, 1998.
    Comments for inclusion in the Rules Docket must be received on or 
before February 6, 1998.

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-21-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
via the Internet using the following address: ``9-ad-
[email protected]''. Comments sent via the Internet must contain 
the docket number in the subject line.
    The service information referenced in this AD may be obtained from 
GE Aircraft Engines, 1000 Western Ave., Lynn, MA 01910; telephone (781) 
594-3140, fax (781) 594-4805. This information may be examined at the 
FAA, New England Region, Office of the Assistant Chief Counsel, 12 New 
England Executive Park, Burlington, MA; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (781) 
238-7146, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The Federal Aviation Administration received 
a report that certain turbine torque rings and compressor drive shafts 
installed on General Electric Company (GE) CJ610 series turbojet and 
CF700 series turbofan engines were forged with a contaminated alloy 
that could reduce the life of the part. The FAA has determined that 
certain heat lots of A286 material were produced with iron-rich 
inclusions during the vendor's normal Vacuum Induction Melt (VIM) 
process. The manufacturer discovered a cooling plate removed from a GE 
CT58 series turboprop engine had been manufactured from this heat lot 
and was found with an inclusion. This heat lot was also used to 
manufacture turbine torque rings and compressor drive shafts on GE 
CJ610 series turbojet and CF700 series turbofan engines. This 
condition, if not corrected, could result in turbine torque ring or 
compressor drive shaft failure due to a manufacturing defect, which 
could result in an uncontained engine failure.
    The FAA has reviewed and approved the technical contents of GE 
CF700 Service Bulletin (SB) No. A72-155, dated May 22, 1997, and GE 
CJ610 SB No. A72-147, dated May 22, 1997, that describes procedures for 
removing affected turbine torque rings and compressor drive shafts from 
service, and replacing with serviceable parts.
    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 an uncontained engine failure and damage to the 
aircraft. This AD requires removing affected turbine torque rings and 
compressor drive shafts from service, and replacing with serviceable 
parts. The actions are required to be accomplished in accordance with 
the SBs described previously.
    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 this 
AD 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

[[Page 64514]]

Docket Number 97-ANE-21-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, Incorporation by 
reference, 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:

97-25-08  General Electric Company: Amendment 39-10232. Docket 97-
ANE-21-AD.

    Applicability: General Electric Company (GE) CJ610 series 
turbojet and CF700 series turbofan engines, with turbine torque 
rings and compressor drive shafts identified in GE CF700 Service 
Bulletin (SB) No. A72-155, dated May 22, 1997, and GE CJ610 SB No. 
A72-147, dated May 22, 1997. These engines are installed on but not 
limited to the following aircraft: Learjet 20 series, Israel 
Aircraft Industries Westwind series, Hansa Jet, Aero Commander Jet 
Commander, Dassault Falcon 20 series, Sabreliner 265 series.

    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 (d) 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 turbine torque ring or compressor drive shaft failure 
due to a manufacturing defect, which could result in an uncontained 
engine failure, accomplish the following:
    (a) For GE CF700 series turbofan engines, accomplish the 
following in accordance with GE CF700 SB No. A72-155, dated May 22, 
1997:
    (1) Remove from service affected turbine torque rings, listed by 
serial number (S/N) in paragraph 1. A.(3a) of GE CF700 SB No. A72-
155, dated May 22, 1997, and replace with serviceable parts, within 
50 hours time in service (TIS), or 60 days after the effective date 
of this AD, whichever occurs first.
    (2) Remove from service affected turbine torque rings and 
compressor drive shafts, listed by S/N in GE paragraph 1.A.(3b) of 
GE CF700 SB No. A72-155, dated May 22, 1997, and replace with 
serviceable parts, within 300 hours TIS, or 12 months after the 
effective date of this AD, whichever occurs first.
    (b) For GE CJ610 series turbojet engines, accomplish the 
following in accordance with GE CJ610 SB No. A72-147, dated May 22, 
1997:
    (1) Remove from service affected turbine torque rings, listed by 
S/N in paragraph 1.A.(3a) of GE CJ610 SB No. A72-147, dated May 22, 
1997, and replace with serviceable parts, within 50 hours TIS, or 60 
days after the effective date of this AD, whichever occurs first.
    (2) Remove from service affected turbine torque rings and 
compressor drive shafts, listed by S/N in paragraph 1.A.(3b) of GE 
CJ610 SB No. A72-147, dated May 22, 1997, and replace with 
serviceable parts, within 300 hours TIS, or 12 months after the 
effective date of this AD, whichever occurs first.
    (c) After the effective date of this AD, installation of 
uninstalled affected parts identified by S/N in the SBs referenced 
in paragraphs (a) and (b) of this AD is prohibited.
    (d) 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.

    (e) 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.
    (f) The actions required by this AD shall be done in accordance 
with the following GE service documents:

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              Document No.                 Pages           Date         
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CF700 SB No. A72-155....................     1-9  May 22, 1997.         
  Total Pages: 9........................                                
CJ610 SB No. A72-147....................     1-9  May 22, 1997.         
  Total Pages: 9........................                                
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    This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
Copies may be obtained from GE Aircraft Engines, 1000 Western Ave., 
Lynn, MA 01910; telephone (781) 594-3140, fax (781) 594-4805. Copies 
may be inspected at the FAA, New England Region, Office of the 
Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; 
or at the Office of the Federal Register, 800 North Capitol Street, 
NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on January 2, 1998.

    Issued in Burlington, Massachusetts, on November 26, 1997.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 97-31862 Filed 12-5-97; 8:45 am]
BILLING CODE 4910-13-U