Document ID: FAA-2012-0817-0014
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2012-12-31T05:00Z

[Federal Register Volume 77, Number 250 (Monday, December 31, 2012)]
[Proposed Rules]
[Pages 76977-76979]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-31362]

[[Page 76977]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0817; Directorate Identifier 99-NE-24-AD]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for certain General Electric Company (GE) CF6-80C2 series turbofan 
engines. That NPRM proposed to supersede an AD that required 
replacement of fuel tubes connected to the fuel flowmeter. That NPRM 
was prompted by several reports of fuel leaks, and two reports of 
engine fire, due to mis-assembled supporting brackets on the fuel tube 
connecting the flowmeter to the Integrated Drive Generator (IDG) fuel-
oil cooler. That NPRM required installation of a new simplified one-
piece supporting bracket to eliminate mis-assembly. This supplemental 
action adds an engine model, alters the list of affected part numbers 
(P/Ns), changes the replacement schedule, and revises our estimated 
cost of compliance. We are reopening the comment period to allow the 
public the opportunity to comment on these proposed changes. We are 
proposing this AD to prevent high-pressure fuel leaks caused by 
improper seating of fuel tube flanges, which could result in an engine 
fire and damage to the airplane.

DATES: We must receive comments on this supplemental NPRM by March 1, 
2013.

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact General 
Electric Company, GE Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 
45215, phone: (513) 552-3272; email: geae.aoc@ge.com. You may view this 
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 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: Kasra Sharifi, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238-7773; 
fax: 781-238-7199; email: kasra.sharifi@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2012-0817; 
Directorate Identifier 99-NE-24-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 issued an NPRM to amend 14 CFR part 39 to include an AD that 
would apply to certain GE CF6-80C2 series turbofan engines. That NPRM 
published in the Federal Register on August 13, 2012 (77 FR 48110). 
That NPRM proposed to supersede AD 2000-04-14, Amendment 39-11597 (65 
FR 10698, February 29, 2000) which had required replacement of certain 
fuel tubes. That NPRM proposed to require installation of a new 
simplified one-piece bracket to eliminate mis-assembly.

Actions Since Previous NPRM Was Issued

    Since we issued the previous NPRM (77 FR 48110, August 13, 2012), 
we received and evaluated comments from the public. The nature of the 
comments caused us to issue this supplemental NRPM to reopen the 
comment period and allow the public the opportunity to comment on the 
changes we have made.

Comments

    The following presents the comments received on the previous NPRM 
(77 FR 48110, August 13, 2012) and the FAA's response to each comment.

Request To Remove Certain Part Number From Final Rule

    Seven air carriers requested that we exclude bolt P/N MS9557-12 
from the final rule because this is a common part used in other 
components of the engine besides the main engine control to flowmeter 
fuel tube.
    We agree. We changed the proposed AD by removing reference to P/N 
MS9557-12 from the compliance and prohibition paragraphs.

Request To Remove Idle Leak Check Requirement

    The Boeing Company (Boeing) and FEDEX Express requested that we 
remove the idle leak check requirement, which they contend is not 
necessary to address the unsafe condition and which is included in 
normal maintenance, and so does not need to be mandated.
    We disagree. We are issuing this AD to prevent fuel leak and fire 
due to mis-assembled connections, and idle leak check is necessary to 
ensure no fuel leaks occur after tube or bracket replacement. We did 
not change the proposed AD.

Request To Alter Mandate for Replacement of Hardware

    Boeing, General Electric Company, and American Airlines requested 
that we change the AD to mandate replacement of only the disconnected 
hardware during on-wing maintenance, and then the remaining balance of 
affected hardware during the next shop visit.
    We agree. We changed the proposed AD to require that for on-wing 
maintenance, only those tubes and

[[Page 76978]]

brackets that had been disconnected would be replaced at that time.

Request To Expand the Applicability

    GE and Boeing requested that we add the GE CF6-80C2B5F engine model 
to the list of applicable engines. Even though the production model of 
this engine used a one-piece design (2021M83G01), some engines may have 
subsequently received bracket P/N 1321M88P001A, allowed by GE Alert 
Service Bulletin (SB) 73-A0401 for the purpose of hardware 
interchangeability.
    We agree. We changed the proposed AD by adding the GE CF6-80C2BF5 
engine to the list of applicable engines specified in paragraph (c).

Request To Incorporate by Reference (IBR) Applicable GE SBs

    Four air carriers requested that applicable GE SBs be incorporated 
by reference in the AD to provide more specific and detailed 
instructions to aid operators in part replacement.
    We partially agree. We agree that GE SBs provide additional 
guidance. We disagree with incorporating the SBs by reference because 
multiple acceptable methods exist for performing the actions required 
by the AD. We did not change the proposed AD.

Request To Clarify Why the AD Mandates Fuel Tube Changes

    Onur Air requested clarification as to why the proposed AD would 
mandate fuel tube changes when the GE SB only applies to engines with a 
certain bracket.
    We disagree. The proposed AD supersedes AD 2000-04-14, Amendment 
39-11597 (65 FR 10698, February 29, 2000). That AD requires replacement 
of certain fuel tube P/Ns. The proposed AD retains that requirement and 
also mandates replacement of certain supporting brackets and spray 
shields. We did not change the proposed AD.

Request To Provide Method To Identify Affected Configuration Without 
Disassembly

    American Airlines requested that the proposed AD provide a method 
to identify the affected fuel tube configuration without disassembling 
the tubes, because P/N 1321M42G04 is located under a loop clamp, making 
it difficult to read the P/N.
    We disagree. Detailed maintenance instructions can be found in the 
Instructions for Continued Airworthiness for the engine. We did not 
change the proposed AD.

Request To Issue a New AD Instead of Superseding a Prior AD

    The National Transportation Safety Board requested that we issue a 
new AD, instead of proposing to supersede AD 2000-04-14, Amendment 39-
11597 (65 FR 10698, February 29, 2000), for actions regarding the 
removal of the bracket. Operators might presume that if they have 
already complied with AD-2000-04-14 that they might also comply with 
the additional requirements (replacement of brackets and spray shield) 
of the proposed supersedure AD.
    We disagree. The proposed supersedure AD addresses the same unsafe 
condition as the original AD, but expands its scope. The proposed 
supersedure AD will receive its own amendment number and AD number, and 
the original AD will be deleted. We did not change the proposed AD.

Request for Changes to the Costs of Compliance

    American Airlines requested that we revise the cost estimate to 
more accurately capture the cost of the spray shield and also to 
include the cost of the idle leak check.
    We agree. In the ``Cost of Compliance'' section of the proposed AD, 
we have changed the cost estimate for each spray shield from $180 to 
$370, and we have included an estimated cost of $1000 per engine for 
the idle leak check.

Request To Clarify Spray Shield Part Numbers

    Delta Airlines requested that we change the conjunction ``and'' 
between the two P/Ns listed in paragraph (f)(4) to ``or'' since each 
engine only has one spray shield to be replaced, and that we add spray 
shield P/N 1606M57G03 to the list, resulting in three specified P/Ns. 
The added part number is an alternative spray shield to P/N 1775M61G01, 
and so is also affected by the AD.
    We partially agree. We agree that P/N 1606M57G03 should be added to 
the list of P/Ns to be removed. We disagree that the conjunction 
``and'' should be changed to ``or'' because all three spray shield P/Ns 
are subject to replacement. We changed the AD to require the 
replacement of P/N 1606M57G03.

Request To Add Historical Information to Preamble

    GE requested that we add more historical information to the 
``Action Since Existing AD was Issued'' paragraph in the AD preamble.
    We disagree. The cited preamble paragraph will not appear in the 
final rule, and so additional historical information will not add value 
to that proposed rule. We did not change the proposed AD.

Request To Provide the P/Ns of Eligible Replacement Parts

    UPS requested that we provide P/Ns of eligible replacement parts.
    We disagree. The purpose of the AD is to identify and mandate 
removal of parts causing the unsafe condition. Operators are required 
to only use parts that are eligible for installation. We did not change 
the proposed AD.

Request To Nullify Need for Compliance if SBs Already Accomplished

    Four air carriers requested that the AD state that no further 
action is required if the applicable GE SBs have already been 
accomplished.
    We disagree. The ``Compliance'' and ``Replacement'' paragraphs 
sufficiently state that compliance actions do not have to be repeated 
if accomplished before the effective date of the AD. We did not change 
the proposed AD.

Request To Withdraw the Proposed AD

    American Airlines requested that we withdraw the requirement to 
incorporate the spray shield on-wing any time the fuel tubes are 
disconnected because disconnecting them is an unnecessary hardship on 
air carriers.
    We disagree. On-wing maintenance to the spray shield and affected 
tubes without removing and replacing them may lead to the unsafe 
condition. We did not change the proposed AD.

FAA's Determination

    We are proposing this supplemental NPRM 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. Certain changes described above expand the scope of the 
original NPRM. As a result, we have determined that it is necessary to 
reopen the comment period to provide additional opportunity for the 
public to comment on this supplemental NPRM.

Proposed Requirements of the Supplemental NPRM

    This supplemental NPRM would require installation of a new 
simplified one-piece bracket to eliminate mis-assembly of supporting 
brackets on the fuel tube connecting the flowmeter to the IDG fuel-oil 
cooler.

Costs of Compliance

    We estimate that this proposed AD would affect 926 GE CF6-80C2 
engines

[[Page 76979]]

installed on airplanes of U.S. registry. We also estimate that one hour 
would be required per engine to accomplish the actions required by this 
AD. The average labor rate is $85 per hour. We also estimate that the 
required parts will cost about $370 per engine. We estimate that the 
cost of the idle leak check is $1,000 per engine. Based on these 
figures, we estimate the total cost of the proposed AD to U.S. 
operators is $3,275,231.

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, 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:

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):

2012-XX-XX General Electric Company: Docket No. FAA-2012-0817; 
Directorate Identifier 99-NE-24-AD.

(a) Comments Due Date

    We must receive comments by March 1, 2013.

(b) Affected ADs

    This AD supersedes AD 2000-04-14, Amendment 39-11597 (65 FR 
10698, February 29, 2000).

(c) Applicability

    This AD applies to all General Electric Company (GE) CF6-80C2 
A1/A2/A3/A5/A8/A5F/B1/B2/B4/B5F/B6/B1F/B2F/B4F/B6F/B7F/D1F turbofan 
engines with fuel tubes, part number (P/N) 1321M42G01, 1334M88G01, 
1374M30G01, 1383M12G01, 1606M57G03, 1606M57G01, or 1775M61G01, or 
supporting bracket, P/N 1321M88P001A, installed.

(d) Unsafe Condition

    This AD was prompted by several reports of fuel leaks, and two 
reports of engine fire, due to mis-assembled supporting brackets on 
the fuel tube connecting the flowmeter to the Integrated Drive 
Generator (IDG) fuel-oil cooler. We are proposing this AD to prevent 
high-pressure fuel leaks caused by improper seating of fuel tube 
flanges, which could result in an engine fire and damage to the 
airplane.

(e) Compliance

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

(f) Replacement

    After the effective date of this AD, if the fuel tubes are 
disconnected for any reason, or at the next engine shop visit, 
whichever occurs first, replace the fuel tubes and brackets with 
improved tubes and brackets eligible for installation. For on-wing 
maintenance, replace only tubes and brackets that have been 
disconnected. Do the following:
    (1) Replace the fuel flowmeter to IDG fuel-oil cooler fuel tube, 
P/N 1321M42G01, with a part eligible for installation.
    (2) For engines with Power Management Controls, replace the Main 
Engine Control to fuel flowmeter fuel tube, P/N 1334M88G01, with a 
part eligible for installation.
    (3) For engines with Full Authority Digital Electronic Controls, 
replace the Hydromechanical Unit to fuel flowmeter fuel tubes, P/Ns 
1383M12G01 and 1374M30G01, with a part eligible for installation.
    (4) Replace supporting bracket, P/N 1321M88P001A, and spray 
shields, P/Ns 1606M57G01, 1606M57G03, and 1775M61G01 with one-piece 
supporting bracket, P/N 2021M83G01.
    (5) Perform an idle leak check after accomplishing paragraphs 
(f)(1), (f)(2), (f)(3), or (f)(4), or any combination thereof.

(g) Prohibition

    After the effective date of this AD, do not install any of the 
following parts into any GE CF6-80C2 series turbofan engines: P/Ns 
1321M42G01, 1321M88P001A, 1334M88G01, 1374M30G01, 1383M12G01, 
1606M57G01, 1606M57G03, and 1775M61G01.

(h) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, FAA, may approve AMOCs 
for this AD. Use the procedures found in 14 CFR 39.19 to make your 
request.

(i) Related Information

    (1) For more information about this AD, contact Kasra Sharifi, 
Aerospace Engineer, Engine Certification Office, FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: 781-238-7773; fax: 781-238-7199; email: 
kasra.sharifi@faa.gov.
    (2) For guidance on the replacements, refer to GE Alert Service 
Bulletins CF6-80C2 SB 73-A0224, CF6-80C2 SB 73-A0231, CF6-80C2 SB 
73-A0401, and CF6-80C2 SB 73-0242.
    (3) For service information identified in this AD, contact 
General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, 
Cincinnati, OH 45215, phone: (513) 552-3272; email: geae.aoc@ge.com. 
You may view this 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.

    Issued in Burlington, Massachusetts on December 20, 2012.
Robert J. Ganley,
Acting Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-31362 Filed 12-28-12; 8:45 am]
BILLING CODE 4910-13-P