[Federal Register: November 12, 2003 (Volume 68, Number 218)]
[Proposed Rules]               
[Page 64001-64002]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12no03-12]                         

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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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[[Page 64001]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-46-AD]
RIN 2120-AA64

 
Airworthiness Directives; General Electric Company CF6-80C2 
Series Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for General Electric Company (GE) CF6-80C2 series turbofan engines. 
This proposed AD would require replacing certain high pressure turbine 
(HPT) stage 1 disks at or before reaching a new reduced life cycle 
limit. This proposed AD is prompted by an updated low-cycle-fatigue 
(LCF) analysis of the HPT stage 1 disk. We are proposing this AD to 
prevent LCF cracking and failure of the HPT stage 1 disk due to 
exceeding the life limit, which could result in an uncontained engine 
failure and damage to the airplane.

DATES: We must receive any comments on this proposed AD by January 12, 
2004.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD:
    [sbull] By mail: Federal Aviation Administration (FAA), New England 
Region, Office of the Regional Counsel, Attention: Rules Docket No. 
2003-NE-46-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
    [sbull] By fax: (781) 238-7055.    [sbull] By e-mail: 9-ane-adcomment@faa.gov.
    You may examine the AD docket, by appointment, at the FAA, New 
England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Karen Curtis, Aerospace Engineer, 
Aircraft Certification Office, FAA, Engine and Propeller Directorate, 
12 New England Executive Office Park, Burlington, MA 01803; telephone 
(781) 238-7192; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. 2003-NE-46-AD'' in the 
subject line of your comments. If you want us to acknowledge receipt of 
your mailed comments, send us a self-addressed, stamped postcard with 
the docket number written on it; we will date-stamp your postcard and 
mail it back to you. We specifically invite comments on the overall 
regulatory, economic, environmental, and energy aspects of the proposed 
AD. If a person contacts us verbally, and that contact relates to a 
substantive part of this proposed AD, we will summarize the contact and 
place the summary in the docket. We will consider all comments received 
by the closing date and may amend the proposed AD in light of those 
comments.
    We are reviewing the writing style we currently use in regulatory 
documents. We are interested in your comments on whether the style of 
this document is clear, and your suggestions to improve the clarity of 
our communications that affect you. You can get more information about 
plain language at http://www.faa.gov/language and http://www
.plainlanguage.gov.

Examining the AD Docket

    You may examine the AD Docket (including any comments and service 
information), by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. See ADDRESSES for the 
location.

Discussion

    GE has completed an updated LCF analysis for the CF6-80C2A5F, CF6-
80C2B5F, CF6-80C2B7F, and CF6-80C2D1F HPT stage 1 disks, part numbers 
(P/Ns) 1531M84G10 and 1531M84G12, and has established a new reduced 
life cycle limit of 10,720 cycles-since-new (CSN) for these disks. In 
January 2003, the FAA became aware of GE's in-process analysis and 
material testing of HPT stage 1 disks, P/Ns 1531M84G10 and 1531M84G12. 
The FAA approved temporary revisions (TRs) to Chapter 5, Life Limits, 
of the engine manual (EM), to incorporate revised life limits for these 
disks based on initial analytical results. The original life limit of 
13,200 CSN for these disks was last published in EM GEK 92451, Revision 
57, dated March 1, 2003. TRs 05-0093 and 05-0094, dated May 15, 2003, 
revised this life limit from 13,200 CSN to 9,000 CSN. The FAA chose to 
wait for final analytical results before taking action to mandate a 
lower life limit. This wait was possible due to the young age of the 
affected disks. The high-cycle disk has accumulated fewer than 7,500 
CSN at this time, which is well below the interim limit of 9,000 CSN 
and the final mandated limit. The FAA now approves GE's final 
analytical results and the reduced life limit of 10,720 CSN. GE issued 
TRs 05-0096 and 05-0097 on June 19, 2003 to revise the life limits 
section of the EM for CF6-80C2A5F, CF6-80C2B5F, CF6-80C2B7F, and CF6-
80C2D1F HPT stage 1 disks, P/Ns 1531M84G10 and 1531M84G12, to 10,720 
CSN. Although interim publications of the EM showed lower life limits 
for this part, those limits were not mandated by an AD. Therefore, an 
AD is now required to mandate the approved 10,720 CSN life limit.

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. Therefore, we are proposing this AD, which 
would require replacing HPT stage 1 disks, P/Ns 1531M84G10 and 
1531M84G12 at or before reaching a new reduced life cycle limit of 
10,720 CSN.

Changes to 14 CFR Part 39--Effect on the Proposed AD

    On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 
47998, July 22, 2002), which governs the FAA's AD system. This 
regulation now includes material that relates to altered products, 
special flight permits, and alternative methods of compliance. This 
material previously was included in each individual AD. Since this 
material

[[Page 64002]]

is included in 14 CFR part 39, we will not include it in future AD 
actions.

Costs of Compliance

    There are about 526 CF6-80C2A5F, CF6-80C2B5F, CF6-80C2B7F, and CF6-
80C2D1F turbofan engines of the affected design in the worldwide fleet. 
We estimate that 208 engines installed on airplanes of U.S. registry 
would be affected by this proposed AD. The proposed action does not 
impose any additional labor costs. The prorated cost of a new HPT stage 
1 disk would cost approximately $43,306 per engine. Based on these 
figures, and on the prorating for the usage of the HPT stage 1 disks, 
the cost of the proposed AD on U.S. operators is estimated to be 
$9,007,648.

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 
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. 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 summary of the costs to comply with this proposal and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2003-NE-46-AD'' in your request.

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 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 adding the following new 
airworthiness directive:

General Electric Company: Docket No. 2003-NE-46-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 12, 
2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to General Electric Company (GE) CF6-
80C2A5F, CF6-80C2B5F, CF6-80C2B7F, and CF6-80C2D1F turbofan engines 
with high pressure turbine (HPT) stage 1 disks, part numbers (P/Ns) 
1531M84G10 or 1531M84G12 installed. These engines are installed on, 
but not limited to, Airbus Industrie A300 and A330 series, Boeing 
747 and 767 series, and McDonnell Douglas MD-11 airplanes.

Unsafe Condition

    (d) This AD was prompted by an updated low-cycle-fatigue (LCF) 
analysis of the HPT stage 1 disk. We are issuing this AD to prevent 
LCF cracking and failure of the HPT stage 1 disk due to exceeding 
the life limit, which could result in an uncontained engine failure 
and damage to the airplane.

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) Replace HPT stage 1 disks, P/Ns 1531M84G10 and 1531M84G12, 
at or before the disk accumulates 10,720 cycles-since-new (CSN).
    (g) After the effective date of this AD, do not install any HPT 
stage 1 disk, P/N 1531M84G10 or 1531M84G12, that exceeds 10,720 CSN.

Alternative Methods of Compliance

    (h) 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.

Material Incorporated by Reference

    (i) None.

Related Information

    (j) None.

    Issued in Burlington, Massachusetts, on November 4, 2003.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 03-28323 Filed 11-10-03; 8:45 am]

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