Document ID: FAA-2006-24171-0010
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: General Electric Company CF6-50C Series Turbofan Engines
Posted Date: 2009-06-24T04:00Z

[Federal Register Volume 74, Number 120 (Wednesday, June 24, 2009)]
[Proposed Rules]
[Pages 30018-30020]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-14815]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24171; Directorate Identifier 2006-NE-08-AD]
RIN 2120-AA64

Airworthiness Directives; General Electric Company CF6-50C Series 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to revise an existing airworthiness directive 
(AD) for General Electric Company (GE) CF6-50C series turbofan engines. 
That AD currently requires reworking certain forward fan stator cases 
and installing a fan module secondary containment shield. This proposed 
AD would require the same actions but would eliminate a certain service 
bulletin from the compliance method. This proposed AD results from a 
review that shows that only one of the service bulletins referenced in 
the original AD is applicable as a compliance method. We are proposing 
this AD revision to prevent uncontained fan blade failures, which can 
result in separation of

[[Page 30019]]

airplane hydraulic lines, damage to critical airplane systems, and 
possible loss of airplane control.

DATES: We must receive any comments on this proposed AD by August 24, 
2009.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.

FOR FURTHER INFORMATION CONTACT: James Rosa, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
james.rosa@faa.gov; telephone (781) 238-7152; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send us any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2006-24171; 
Directorate Identifier 2006-NE-08-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light 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 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets, including, if provided, the name of the individual who 
sent the comment (or signed the comment on behalf of an association, 
business, labor union, etc.). You may review the DOT's complete Privacy 
Act Statement in the Federal Register published on April 11, 2000 (65 
FR 19477-78).

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office 
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 Operations office (telephone (800) 647-5527) is 
the same as the Mail address provided in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

Discussion

    On May 22, 2007, we issued AD 2007-11-18, Amendment 39-15075 (72 FR 
30249, May 31, 2007). That AD requires reworking certain forward fan 
stator cases and installing a fan module secondary containment shield. 
That AD resulted from reports of uncontained fan blade failures. That 
condition, if not corrected, could result in separation of airplane 
hydraulic lines, damage to critical airplane systems, and possible loss 
of airplane control due to uncontained fan blade failures.

Actions Since AD 2007-11-18 Was Issued

    Since AD 2007-11-18 was issued, we determined that we don't need GE 
Service Bulletin No. CF6-50 S/B 72-0986, Revision 2, dated March 21, 
2007, applicable to DC-10 series aircraft, in order to satisfy our 
corrective action requirements. Accordingly, this proposed AD deletes 
this SB as a required corrective action.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. For this reason, we are proposing this AD 
revision, which would require reworking certain forward fan stator 
cases and installing a fan module secondary containment shield on 
Airbus A300 series airplanes, and would eliminate GE Service Bulletin 
No. CF6-50 S/B 72-0986, Revision 2, dated March 21, 2007. The proposed 
AD would require that you do the rework and installations using GE 
Service Bulletin No. CF6-50 S/B 72-0985, Revision 2, dated March 21, 
2007 only.

Costs of Compliance

    We estimate that this AD would affect 40 CF6-50C series turbofan 
engines installed on airplanes of U.S. registry. We also estimate that 
it would take about 2.5 work hours per engine to perform the actions, 
and that the average labor rate is $80 per work hour. Required parts 
would cost about $9,451 per engine. Based on these figures, we estimate 
the total cost of the AD to U.S. operators to be $386,040.

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 have 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 that the proposed AD:
    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. Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

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

[[Page 30020]]

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration 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 removing Amendment 39-15075 (72 FR 
30249, May 31, 2007), and by adding a new airworthiness directive, to 
read as follows:

General Electric Company: Docket No. FAA-2006-24171; Directorate 
Identifier 2006-NE-08-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by August 24, 
2009.

Affected ADs

    (b) This AD revises AD 2007-11-18, Amendment 39-15075.

Applicability

    (c) This AD applies to General Electric Company (GE) CF6-50C, 
CF6-50C1, CF6-50C2, and CF6-50C2R turbofan engines, with a forward 
fan stator case, part number (P/N) 9064M53G04, G05, G06, G07, G08, 
G09, G10, G12, or G13, or P/N 9173M37G01, G02, G03, G04, G05, or G06 
installed. These engines are installed on, but not limited to, 
Airbus A300, McDonnell Douglas DC-10 series, and DC-10-30F (KC-10A, 
KDC-10) airplanes.

Unsafe Condition

    (d) This AD revision results from a review that shows that only 
one of the service bulletins referenced in the original AD is 
applicable as a compliance method. We are issuing this AD to prevent 
uncontained fan blade failures, which can result in separation of 
airplane hydraulic lines, damage to critical airplane systems, and 
possible loss of airplane control.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.
    (f) At the next engine shop visit after the effective date of 
this AD, but no later than June 30, 2010, rework the forward fan 
stator case and install the fan module secondary containment shield.
    (1) For engines on Airbus 300 series airplanes, use paragraph 3, 
Accomplishment Instructions, of GE Service Bulletin (SB) No. CF6-50 
S/B 72-0985, Revision 2, dated March 21, 2007, to do the rework and 
installation.
    (2) Deleted.
    (g) The rework and installation specified in paragraph (f)(1) of 
this AD can also be done on-wing.

Previous Credit

    (h) Previous credit is allowed for fan stator cases reworked and 
containment shields installed using GE SB No. CF6-50 S/B 72-0985, 
dated December 2, 1991 or Revision 1, dated September 15, 1998 
before the effective date of this AD.

Alternative Methods of Compliance

    (i) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Related Information

    (j) European Aviation Safety Agency airworthiness directive 
2004-0007, dated December 15, 2004, also addresses the subject of 
this AD.
    (k) Contact James Rosa, Aerospace Engineer, Engine Certification 
Office, FAA, Engine and Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: james.rosa@faa.gov; 
telephone (781) 238-7152; fax (781) 238-7199, for more information 
about this AD.
    (l) Contact General Electric Company via Lockheed Martin 
Technology Services, 10525 Chester Road, Suite C, Cincinnati, Ohio 
45215, telephone (513) 672-8400, fax (513) 672-8422, for a copy of 
the service information referenced in this AD.

    Issued in Burlington, Massachusetts, on June 17, 2009.
Carlos Pestana,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E9-14815 Filed 6-23-09; 8:45 am]
BILLING CODE 4910-13-P