[Federal Register Volume 64, Number 194 (Thursday, October 7, 1999)]
[Proposed Rules]
[Pages 54594-54596]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-26212]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-ANE-49-AD]
RIN 2120-AA64
Airworthiness Directives; General Electric Company CF6-80A, CF6-
80C2, and CF6-80E1 Series Turbofan Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to General Electric Company
(GE) CF6-80A, CF6-80C2, and CF6-80E1 series turbofan engines, that
currently requires revisions to the Life Limits Section of the
manufacturer's Instructions for Continued Airworthiness (ICA) to
include required enhanced inspection of selected critical life-limited
parts at each piece-part exposure. This action would add additional
disk bore eddy current inspections (ECI) for the high pressure turbine
rotor (HPTR) Stage 1 and 2 disks for all affected engine models, and
would add fan forward shaft inspections for the CF6-80C2 engine model
only. This proposal is prompted by additional focused inspection
procedures that have been developed by the manufacturer. The actions
specified by this proposed AD are intended to prevent critical life-
limited rotating engine part failure, which could result in an
uncontained engine failure and damage to the airplane.
DATES: Comments must be received by December 6, 1999.
ADDRESSES: Submit comments to the Federal Aviation Administration
(FAA), New England Region, Office of the Regional Counsel, Attention:
Rules Docket No. 98-ANE-49-AD, 12 New England Executive Park,
Burlington, MA 01803-5299. 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.
Comments may be inspected at this location between 8:00 a.m. and 4:30
p.m., Monday through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Karen Curtis, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803-5299; telephone (781)
238-7192, fax (781) 238-7199.
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 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 98-ANE-49-AD.'' 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 Regional Counsel,
Attention: Rules Docket No. 98-ANE-49-AD, 12 New England Executive
Park, Burlington, MA 01803-5299.
Discussion
On April 2, 1999, the Federal Aviation Administration (FAA) issued
airworthiness directive (AD) 99-08-13, Amendment 39-11119 (64 FR 17951,
April 13, 1999), to require revisions to the Life Limits Section of the
manufacturer's Instructions for Continued Airworthiness (ICA) for
General Electric Company (GE) CF6-80A, CF6-80C2, and CF6-80E1 series
turbofan engines to include required enhanced inspection of selected
critical life-limited parts at each piece-part exposure.
New Inspection Procedures
Since the issuance of that AD, GE has developed additional focused
inspection procedures. This proposal would add disk bore eddy current
inspections (ECI) for the high pressure turbine rotor (HPTR) Stage 1
and 2 disks on all affected engine models, and would add fan forward
shaft inspections for the CF6-80C2 engine model only.
Proposed Actions
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 supersede AD 99-08-13 to add disk bore ECI for the
HPTR Stage 1 and 2 disks on all affected engine models, and to add fan
forward shaft inspections for the CF6-80C2 engine model only. The
inspections would be required at each piece-part opportunity.
Economic Analysis
The FAA estimates that 700 engines installed on airplanes of US
registry would be affected by this proposed AD, that it would take
approximately 4 work hours per engine to accomplish the proposed new
disk bore ECI for the HPTR Stage 1 and 2 disks on all affected engine
models, and that the average labor rate is $60 per work hour. The total
cost of the new disk bore ECI for the HPTR Stage 1 and 2 disks
inspections per engine would be approximately $240. The FAA estimates
that approximately 83 HPTR Stage 1 and 2 disks would be exposed to the
piece-part level per year; therefore, the total annual cost for the
added bore ECI is estimated to be $19,920.
The FAA estimates that it would take approximately 4 work hours per
engine to accomplish the proposed new fan forward shaft inspections on
the CF6-80C2 engine model. The total cost of the new fan forward shaft
inspections per
[[Page 54595]]
engine would be approximately $240. The FAA estimates that
approximately 31 fan forward shafts would be exposed to the piece-part
level per year; therefore, the total annual cost for the added fan
forward shaft inspections is estimated to be $7,440.
Regulatory Impact
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 removing Amendment 39-11119 (64 FR
17951, April 13, 1999), and by adding a new airworthiness directive, to
read as follows:
General Electric Company: Docket No. 98-ANE-49-AD. Supersedes AD 99-
08-13, Amendment 39-11119.
Applicability: General Electric Company (GE) CF6-80A, CF6-80C2,
and CF6-80E1 series turbofan engines, installed on but not limited
to Airbus Industrie A300, A310, and A330 series, Boeing 747 and 767
series, and McDonnell Douglas MD-11 series airplanes.
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 (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: Required as indicated, unless accomplished
previously.
To prevent critical life-limited rotating engine part failure,
which could result in an uncontained engine failure and damage to
the airplane, accomplish the following:
Inspections
(a) Within the next 30 days after the effective date of this AD,
revise the manufacturer's Life Limits Section of the Instructions
for Continued Airworthiness (ICA), and for air carrier operations
revise the approved continuous airworthiness maintenance program, by
adding the following: ``MANDATORY INSPECTIONS''
(1) Perform inspections of the following parts at each piece-
part opportunity in accordance with the instructions provided in the
applicable manual provisions:
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Part nomenclature Part No. (P/N) Inspect per engine manual
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For CF6-80A Engines:
Disk, Fan Rotor, Stage 1.............................. All.................. 72-21-03 Paragraph 3.
Fluorescent-Penetrant
Inspect, and 72-21-03
Paragraph 4. Eddy Current
Inspect.
Disk, HPT Rotor, Stage One............................ All.................. 72-53-02 Paragraph 3.
Fluorescent-Penetrant-
Inspect Disk/Shaft per 70-32-
02, and 72-53-02 Paragraph
6. Eddy Current Inspection,
and 72-53-02 Paragraph 7.
Disk Bore Area Eddy Current
Inspection.
Disk, HPT Rotor, Stage Two............................ All.................. 72-53-06 Paragraph 3.
Fluorescent-Penetrant
Inspection, and 72-53-06
Paragraph 6. Eddy Current
Inspection of Rim Boltholes
for Cracks, and 72-53-06
Paragraph 7. Disk Bore Area
Eddy Current Inspection.
For CF6-80C2 Engines:
Disk, Fan Rotor, Stage 1.............................. All.................. Task 72-21-03-200-000-004
Fluorescent-Penetrant
Inspection, and Task 72-21-
03-200-000-008 Eddy Current
Inspect Fan Rotor Disk Stage
1 Bore, Forward and Aft Hub
Faces, and Bore Radii.
Shaft, Fan Forward,................................... All.................. Task 72-21-05-200-000-001
Fluorescent Penetrant
Inspection, and Task 72-21-
05-200-000-005 Vent Hole
Eddy Current Inspection.
Disk, HPT Rotor Stage One............................. All.................. Task 72-53-02-200-000-001
Fluorescent-Penetrant
Inspect the HPT Rotor Stage
1 Disk/Shaft, and Task 72-53-
02-200-000-005 Eddy Current
Inspection, and Task 72-53-
02-200-000-006 Disk Bore
Area Eddy Current
Inspection.
Disk, HPT Rotor Stage Two............................. All.................. Task 72-53-06-200-000-002
Fluorescent-Penetrant
Inspect the Stage 2 Disk,
and Task 72-53-06-200-000-
006 Eddy Current Inspection
of the HPTR Stage 2 Rim
Boltholes, and Task 72-53-06-
200-000-007 Disk Bore Area
Eddy Current Inspection.
For CF6-80E1 Engines:
Disk, Fan Rotor, Stage One............................ All.................. Task 72-21-03-230-051
Fluorescent-Penetrant
Inspection, and Task 72-21-
03-250-051 or 72-21-03-250-
052 Eddy Current Inspection.
HPT Disk, Stage One................................... All.................. Task 72-53-02-230-51
Fluorescent-Penetrant
Inspection, and Task 72-53-
02-200-001-005 Eddy Current
Inspection, and Task 72-53-
02-200-001-006 Disk Bore
Area Eddy Current
Inspection.
HPT Disk, Stage Two................................... All.................. Task 72-53-06-230-051
Fluorescent-Penetrant
Inspection, and Task 72-53-
06-200-001-006 Eddy Current
Inspection of the HPTR Stage
2 Rim Boltholes, and Task 72-
53-06-200-001-007 Disk Bore
Area Eddy Current
Inspection.
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[[Page 54596]]
(2) For the purposes of these mandatory inspections, piece-part
opportunity means:
(i) The part is considered completely disassembled when
accomplished in accordance with the disassembly instructions in the
manufacturer's engine manual; and
(ii) The part has accumulated more than 100 cycles in service
since the last piece-part opportunity inspection, provided that the
part was not damaged or related to the cause for its removal from
the engine.''
(b) Except as provided in paragraph (c) of this AD, and
notwithstanding contrary provisions in section 43.16 of the Federal
Aviation Regulations (14 CFR 43.16), these mandatory inspections
shall be performed only in accordance with the Life Limits Section
of the manufacturer's ICA.
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 Engine Certification Office (ECO). Operators
shall submit their requests through an appropriate FAA Principal
Maintenance Inspector (PMI), who may add comments and then send it
to the ECO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this airworthiness directive,
if any, may be obtained from the ECO.
Ferry Flights
(d) 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 airplane to a location where
the requirements of this AD can be accomplished.
Continuous Airworthiness Maintenance Program
(e) FAA-certificated air carriers that have an approved
continuous airworthiness maintenance program in accordance with the
record keeping requirement of Sec. 121.369(c) of the Federal
Aviation Regulations (14 CFR 121.369(c)) of this chapter must
maintain records of the mandatory inspections that result from
revising the Life Limits Section of the Instructions for Continuous
Airworthiness (ICA) and the air carrier's continuous airworthiness
program. Alternately, certificated air carriers may establish an
approved system of record retention that provides a method for
preservation and retrieval of the maintenance records that include
the inspections resulting from this AD, and include the policy and
procedures for implementing this alternate method in the air
carrier's maintenance manual required by Sec. 121.369(c) of the
Federal Aviation Regulations (14 CFR 121.369(c)); however, the
alternate system must be accepted by the appropriate PMI and require
the maintenance records be maintained either indefinitely or until
the work is repeated. Records of the piece-part inspections are not
required under Sec. 121.380(a)(2)(vi) of the Federal Aviation
Regulations (14 CFR 121.380(a)(2)(vi)). All other Operators must
maintain the records of mandatory inspections required by the
applicable regulations governing their operations.
Note 3: The requirements of this AD have been met when the
engine manual changes are made and air carriers have modified their
continuous airworthiness maintenance plans to reflect the
requirements in the engine manuals.
Issued in Burlington, Massachusetts, on September 30, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 99-26212 Filed 10-6-99; 8:45 am]
BILLING CODE 4910-13-P