Document ID: FAA-2011-0982-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: General Electric Co. Turbofan Engines
Posted Date: 2011-10-18T04:00Z

[Federal Register Volume 76, Number 201 (Tuesday, October 18, 2011)]
[Proposed Rules]
[Pages 64291-64293]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-26825]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0982; Directorate Identifier 2011-NE-09-AD
RIN 2120-AA64

Airworthiness Directives; General Electric Company (GE) Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
GE CF6-80C2A1, CF6-80C2A2, CF6-80C2A3, CF6-80C2A5, CF6-80C2A5F, CF6-
80C2A8, CF6-80C2B1, CF6-80C2B1F, CF6-80C2B1F1, CF6-80C2B1F2, CF6-
80C2B2, CF6-80C2B2F, CF6-80C2B3F, CF6-80C2B4, CF6-80C2B4F, CF6-80C2B5F, 
CF6-80C2B6, CF6-80C2B6F, CF6-80C2B6FA, CF6-80C2B7F, CF6-80C2B8F, CF6-
80C2D1F, CF6-80C2K1F, and CF6-80C2L1F turbofan engines, including 
engines marked on the engine data plate as CF6-80C2B7F1. This proposed 
AD was prompted by a report of a supplier shipping a batch of 
nonconforming No. 3 bearing packings that had incorrect cooling holes, 
and by subsequent reports of nonconforming No. 3 bearing packings being 
installed on engines in service. This proposed AD would require a one-
time inspection of the No. 3 bearing packing for an incorrect cooling 
hole size and, if it is found nonconforming, removing the packing and 
removing certain engine rotating life-limited parts, if they were 
operated with the wrong packing for a specified number of cycles. We 
are proposing this AD to prevent an uncontained failure of the high-
pressure compressor (HPC) rotor or the low-pressure turbine (LPT) rotor 
or both, which could cause damage to the airplane.

DATES: We must receive comments on this proposed AD by December 2, 
2011.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact GE-
Aviation M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215, telephone 
513-552-3272; e-mail: geae.aoc@ge.com. You may review copies of the 
referenced service information at the FAA, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA. For 
information on the availability of this material at the FAA, call 781-
238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD

[[Page 64292]]

docket contains this proposed AD, the regulatory evaluation, any 
comments received, and other information. The street address for the 
Docket Office (phone: 800-647-5527) is in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Tomasz Rakowski, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238-7735; 
fax: 781-238-7199; e-mail: tomasz.rakowski@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2011-0982; 
Directorate Identifier 2011-NE-09-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We received a report that a supplier shipped a batch of 
nonconforming No. 3 bearing packings, part number (P/N) 1292M70P04, 
with undersized cooling holes. The No. 3 bearing packing design did not 
feature permanent part markings and parts could be confused when being 
installed. After GE changed the design to introduce part marking on all 
new-made parts and added secondary inspections to the CF6-80C2 engine 
manual section 72-23-00 Fan Frame Assembly, customers reported several 
nonconforming No. 3 bearing packings, various P/Ns, found installed on 
engines in-service outside of the known population of engines affected 
by the quality escape. The nonconformance of No. 3 bearing packings 
will result in incorrect HPC and LPT rotor bore cooling and, if not 
corrected, could result in a reduced parts life of the life-limited HPC 
rotor stage 10-through-stage 14 spool, the HPC rotor stage 11-through-
stage 14 spool, the LPT rotor stage 3 disk, and the LPT rotor stage 4 
disk. Because the problem exists beyond the known population of engines 
affected by the quality escape and the consequences represent an unsafe 
condition in all affected engines in service, it is necessary to 
inspect the No. 3 bearing packing configuration of the entire fleet. 
This condition, if not corrected, could result in failure of the HPC 
rotor or the LPT rotor or both, which could cause uncontained engine 
failure and damage to the airplane.

Relevant Service Information

    We reviewed GE Service Bulletin (SB) CF6-80C2 S/B 72-1405, dated 
June 30, 2011. The SB describes procedures for inspecting and removing 
the nonconforming No. 3 bearing packing, and determining the effect of 
nonconforming packing on the HPC and LPT rotor bore cooling.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require:
     A one-time inspection of the No. 3 bearing packing at the 
next engine shop visit, but not later than 5,500 cycles-in-service 
(CIS) since the last engine shop visit where the fan was removed from 
the core.
     Removing the No. 3 bearing packing if it is found to be 
nonconforming within the above specified times.
     Removing certain rotating parts if they have operated more 
than 5,500 CIS with the wrong packing configuration.

Differences Between the Proposed AD and the Service Information

    This proposed AD includes CF6 engine models CF6-80C2B1F1, CF6-
80C2B1F2, CF6-80C2B3F, and CF6-C2B7F1 in the Applicability paragraph 
(c). The GE service information does not include these engine models.

Costs of Compliance

    We estimate that this proposed AD would affect 688 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 1 work-hour per engine to perform the inspection and 1 work-
hour to replace the No. 3 bearing packing, if found nonconforming. The 
average labor rate is $85 per work-hour. Required parts would cost 
about $488 per engine to replace an anticipated quantity of 21 No. 3 
bearing packings. Based on these figures, we estimate the total cost of 
this proposed AD to U.S. operators to be $70,513. GE has informed us 
that they may cover these costs under warranty.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify 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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

[[Page 64293]]

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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

General Electric Company (GE): Docket No. FAA-2011-0982; Directorate 
Identifier 2011-NE-09-AD.

(a) Comments Due Date

    We must receive comments by December 2, 2011.

(b) Affected ADs

    None.

(c) Applicability

    This AD is applicable to all GE CF6-80C2A1, CF6-80C2A2, CF6-
80C2A3, CF6-80C2A5, CF6-80C2A5F, CF6-80C2A8, CF6-80C2B1, CF6-
80C2B1F, CF6-80C2B1F1, CF6-80C2B1F2, CF6-80C2B2, CF6-80C2B2F, CF6-
80C2B3F, CF6-80C2B4, CF6-80C2B4F, CF6-80C2B5F, CF6-80C2B6, CF6-
80C2B6F, CF6-80C2B6FA, CF6-80C2B7F, CF6-80C2B8F, CF6-80C2D1F, CF6-
80C2K1F and CF6-80C2L1F turbofan engines, including engines marked 
on the engine data plate as CF6-80C2B7F1.

(d) Unsafe Condition

    This AD was prompted by a report of a supplier shipping a batch 
of nonconforming No. 3 bearing packings that had an incorrect size 
of cooling holes and by several subsequent reports of nonconforming 
No. 3 bearing packings being installed on engines in service. The 
nonconformance of No. 3 bearing packings will result in incorrect 
high-pressure compressor (HPC) rotor and low-pressure turbine (LPT) 
rotor bore cooling and, if not corrected, could result in a reduced 
parts life of the life-limited rotating parts. We are issuing this 
AD to prevent an uncontained failure of the high-pressure compressor 
(HPC) rotor or the low-pressure turbine (LPT) rotor or both, which 
could cause damage to the airplane.

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(f) One-Time Inspection of the No. 3 Bearing Packing and Disposition of 
Affected Rotating Parts

    (1) Perform a one-time inspection of the No. 3 bearing packing 
at the next engine shop visit, but not later than 5,500 cycles-in-
service (CIS) since the last engine shop visit, where the fan was 
removed from the core. Use paragraphs 3.A.(1) through 3.A.(1).(a) of 
the Accomplishment Instructions of GE Service Bulletin (SB) No. CF6-
80C2 S/B 72-1405, dated June 30, 2011.
    (2) If the packing part number (P/N) is determined not eligible 
for installation on the engine, then before further flight:
    (i) Remove the nonconforming packing from service; and
    (ii) Remove the following rotating parts from service, if they 
were operated for 5,500 CIS or more with a packing determined to be 
other than a ``CORRECT FLOW'' packing using paragraph 3.A.(1).(b) of 
the Accomplishment Instructions of SB No. CF6-80C2 S/B 72-1405, 
dated June 30, 2011:
    (A) HPC rotor stage 10-through-14 spool, any P/N,
    (B) HPC rotor stage 11-through-14 spool, any P/N,
    (C) LPT rotor stage 3 disk, P/N 9373M53P05, and
    (D) LPT rotor stage 4 disk, P/N 9373M54P03.

(g) Definition

    For the purposes of this AD, an engine shop visit is the 
induction of an engine into the shop after the effective date of 
this AD, where the separation of a major engine flange occurs; 
except the following maintenance actions, or any combination, are 
not considered engine shop visits:
    (1) Introduction of an engine into a shop solely for removal of 
the compressor top or bottom case for airfoil maintenance or 
variable stator vane bushing replacement.
    (2) Introduction of an engine into a shop solely for replacement 
of the turbine rear frame.
    (3) Introduction of an engine into a shop solely for replacement 
of the accessory gearbox or transfer gearbox, or both.

(h) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, has the authority 
to approve AMOCs for this AD, if requested using the procedures 
found in 14 CFR 39.19.

(i) Related Information

    (1) For more information about this AD, contact Tomasz Rakowski, 
Aerospace Engineer, Engine Certification Office, FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: 781-238-7735; fax: 781-238-7199; e-mail: 
tomasz.rakowski@faa.gov.
    (2) For service information identified in this AD, contact GE-
Aviation M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215, phone 
513-552-3272; e-mail: geae.aoc@ge.com. You may review copies of the 
referenced service information at the FAA, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA, 01803. 
For information on the availability of this material at the FAA, 
call 781-238-7125.

    Issued in Burlington, Massachusetts, on October 6, 2011.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-26825 Filed 10-17-11; 8:45 am]
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