[Federal Register Volume 68, Number 222 (Tuesday, November 18, 2003)]
[Proposed Rules]
[Pages 65000-65002]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-28739]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-43-AD]
RIN 2120-AA64


Airworthiness Directives; General Electric Company (GE) CF6-80C2 
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 GE CF6-80C2 turbofan engines with certain part number (P/N) high 
pressure turbine stage 2 nozzle guide vanes (HPT S2 NGVs) installed. 
This proposed AD would require flex borescope inspections of HPT S2 
NGVs installed in CF6-80C2 turbofan engines. This proposed AD is 
prompted by an uncontained engine failure due to HPT S2 NGV distress. 
We are proposing this AD to prevent blade failure from HPT S2 NGV 
distress, which could result in an uncontained engine failure.

DATES: We must receive any comments on this proposed AD by January 20, 
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-43-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
    [sbull] By fax: (781) 238-7055.
    [sbull] By e-mail: [email protected].
    You can get the service information identified in this proposed AD 
from General Electric Company via Lockheed Martin Technology Services, 
10525 Chester Road, suite C, Cincinnati, Ohio 45215, telephone (513) 
672-8400; fax (513) 672-8422.
    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: Eugene Triozzi, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA; telephone (781) 238-7148; 
fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

[[Page 65001]]

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-43-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

    On May 18, 2001, an uncontained engine failure and an in-flight 
shutdown occurred on a CF6-80C2 engine installed in an Airbus A300 
airplane. The engine nacelle was penetrated, and damage occurred to 
wing skin panels and an inboard aileron. Investigation revealed that 
the uncontained engine failure was caused by cracking and sagging of 
HPT S2 NGVs, which resulted in multiple HPT stage 2 blade failure and 
uncontainment at the low pressure turbine case. To date, three 
uncontained failures of this type on CF6-80C2 engines have been 
reported. Additionally, twelve reports have been received of HPT S2 NGV 
outer airfoil fillet cracking, NGV sagging, and HPT stage 2 blade 
damage. Eleven of these report findings resulted in engine removal, and 
one finding was discovered during engine disassembly. Similar events 
have occurred on other CF6 engine models with similar design HPT S2 
NGVs, which have resulted in nacelle penetration and minor airplane 
damage. CF6-80C2 engines with pre-service bulletin (SB) No. S/B 72-0978 
HPT S2 NGVs installed, are more susceptible to airfoil outer fillet 
cracking. This cracking can propagate to a condition where the nozzle 
segment sags backward and contacts the HPT stage 2 blade row. This 
contact can progress to notching of the blade airfoil at the root and 
lead to blade failure. The actions specified in this AD are intended to 
prevent blade failure from HPT S2 NGV distress, which could result in 
an uncontained engine failure.

Relevant Service Information

    We have reviewed and approved the technical contents of GE SB No. 
CF6-80C2 S/B 72-0952, Revision 6, dated May 5, 2003, that describes 
procedures for initial and repetitive flex borescope inspections of 
affected HPT S2 NGVs.

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 flex borescope inspections of the following P/N HPT S2 
NGVs installed in CF6-80C2A1, -80C2A2, -80C2A3, -80C2A5, -80C2A5F, -
80C2A8, -80C2B1, -80C2B1F, -80C2B2, -80C2B2F, -80C2B4, -80C2B4F, -
80C2B5F, -80C2B6, -80C2B6F, -80C2B6FA, -80C2B7F, and -80C2D1F turbofan 
engines:
    [sbull] P/N 1347M66G03, P/N 1347M66G04, and P/Ns 1815M81G01 through 
1815M81G07, if insert P/N 1957M40G01/G02 was installed during repair.
    [sbull] P/Ns 9373M80G07 through 9373M80G22, and P/Ns 9373M80G25 
through 9373M80G32, if insert P/N 1957M40G01/G02 was installed during 
repair, or if NGV was repaired by GE between April 1, 1998 through 
September 30, 1999.
    [sbull] P/Ns 9373M80G33 through 9373M80G36.
    [sbull] P/Ns 2080M38G01 through 2080M38G16, and P/Ns 2080M38G19 
through 2080M38G24.
    [sbull] P/Ns 2080M19G01 through 2080M19G04, P/Ns 2080M19G07 through 
2080M19G16, P/Ns 2080M19G19 through 2080M19G46, P/Ns 2080M19G49 through 
2080M19G70, and P/Ns 2080M19G73 through 2080M19G80.

The proposed AD would require you to use the service information 
described previously to perform these actions.

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

Costs of Compliance

    There are about 1,100 GE CF6-80C2 turbofan engines of the affected 
design in the worldwide fleet. We estimate that 300 of these engines 
installed on airplanes of U.S. registry would be affected by this 
proposed AD. We also estimate that it would take approximately 2 work 
hours per engine to perform the proposed inspections on engines that 
exhibit no damage, and therefore require no mapping of damage, and that 
the average labor rate is $65 per work hour. Based on these figures, we 
estimate the total cost of the proposed AD to U.S. operators to be 
$39,000.

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-43-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

[[Page 65002]]

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-43-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 20, 
2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to General Electric Company (GE) CF6-80C2A1, 
-80C2A2, -80C2A3, -80C2A5, -80C2A5F, -80C2A8, -80C2B1, -80C2B1F, -
80C2B2, -80C2B2F, -80C2B4, -80C2B4F, -80C2B5F, -80C2B6, -80C2B6F, -
80C2B6FA, -80C2B7F, and -80C2D1F turbofan engines, with the part 
numbers (P/Ns) of high pressure turbine (HPT) stage 2 nozzle guide 
vanes (HPT S2 NGVs) listed in the following Table 1, installed:

                     Table 1.--Affected HPT S2 NGVs
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            HPT S2 NGV:                         Provided that:
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P/N 1347M66G03, P/N 1347M66G04, and  Insert, P/N 1957M40G01/G02 was
 P/Ns 1815M81G01 through 1815M81G07.  installed during repair.
P/Ns 9373M80G07 through 9373M80G22,  Insert, P/N 1957M40G01/G02 was
 and P/Ns 9373M80G25 through          installed during repair, or NGV
 9373M80G32.                          was repaired by GE between April
                                      1, 1998 through September 30,
                                      1999.
P/Ns 9373M80G33 through 9373M80G36.
P/Ns 2080M38G01 through 2080M38G16,
 and P/Ns 2080M38G19 through
 2080M38G24.
P/Ns 2080M19G01 through 2080M19G04,
 P/Ns 2080M19G07 through
 2080M19G16, P/Ns 2080M19G19
 through 2080M19G46, P/Ns
 2080M19G49 through 2080M19G70, and
 P/Ns 2080M19G73 through
 2080M19G80.
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These engines are installed on, but not limited to, Airbus A300, 
Airbus A310, Boeing 747, Boeing 767, and McDonnell Douglas MD-11 
airplanes.

Unsafe Condition

    (d) This AD is prompted by an uncontained engine failure due to 
HPT S2 NGV distress. We are issuing this AD to prevent blade failure 
from HPT S2 NGV distress, which could result in an uncontained 
engine failure.

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.

Initial Flex Borescope Inspection of NGVs

    (f) Flex borescope-inspect the NGVs, following paragraph 3. of 
Accomplishment Instructions of GE Service Bulletin (SB) No. CF6-80C2 
S/B 72-0952, Revision 6, dated May 5, 2003, as follows:

Initial Inspection Thresholds

    (1) For all P/N NGVs except for P/Ns 9373M80G33 through 
9373M80G36 that were installed new at time of original build or were 
installed new or used and serviceable (not repaired) at HPT 
overhaul, initial-inspect after the effective date of this AD at the 
following applicable interval:
    (i) For CF6-80C2A2, -80C2B2, and -80C2B2F engines, inspect at or 
before accumulating 1,600 HPT cycles-since-overhaul (CSO).
    (ii) For CF6-80C2A1, -80C2A3, -80C2A5, -80C2A5F, -80C2A8, -
80C2B1, -80C2B1F, -80C2B4, -80C2B4F, -80C2B5F, -80C2B6, -80C2B6F, -
80C2B6FA, -80C2B7F, and -80C2D1F engines, inspect at or before 
accumulating 800 CSO.

Initial Inspection Thresholds for NGVs P/Ns 9373M80G33 Through 
9373M80G36 Installed at HPT Overhaul

    (2) For NGVs P/Ns 9373M80G33 through 9373M80G36 that were 
installed new at the time of original engine build, initial-inspect 
after the effective date of this AD at the following applicable 
interval:
    (i) For CF6-80C2A2, -80C2B2, and -80C2B2F engines, inspect at or 
before accumulating 3,600 CSO.
    (ii) For CF6-80C2A1, -80C2A3, -80C2A8, -80C2B1, -80C2B1F, -
80C2B4, and -80C2B4F engines, inspect at or before accumulating 
3,000 CSO.
    (iii) For CF6-80C2A5, -80C2A5F, -80C2B5F, -80C2B6, -80C2B6F, -
80C2B6FA, -80C2B7F, and -80C2D1F engines, inspect at or before 
accumulating 2,800 CSO.

Initial Inspection Thresholds for Original Build NGVs P/Ns 9373M80G33 
Through 9373M80G36

    (3) For NGVs P/Ns 9373M80G33 through 9373M80G36 that were 
installed new, or used and serviceable (not repaired) at HPT 
overhaul, initial-inspect after the effective date of this AD at the 
following applicable interval:
    (i) For CF6-80C2A2, -80C2B2, and -80C2B2F engines, inspect at or 
before accumulating 2,400 CSO.
    (ii) For CF6-80C2A1, -80C2A3, -80C2A5, -80C2A5F, -80C2A8, -
80C2B1, -80C2B1F, -80C2B4, -80C2B4F, -80C2B5F, -80C2B6, -80C2B6F, -
80C2B6FA, -80C2B7F, and -80C2D1F engines, inspect at or before 
accumulating 1,600 CSO.

Reinspection

    (g) Reinspect or remove from service NGVs following the 
Conditions and Reinspection intervals listed in the ``Inspection 
Table for Cracking in the Airfoil Outer Fillet'', Figure 5, of GE SB 
No. CF6-80C2 S/B 72-0952, Revision 6, dated May 5, 2003.

Engines With Mixed NGV Configurations

    (h) For engines with mixed NGV configurations of part numbers or 
repair status, use the lowest applicable initial inspection 
thresholds and re-inspection intervals.

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.

Material Incorporated by Reference

    (j) You must use GE SB No. CF6-80C2 S/B 72-0952, Revision 6, 
dated May 5, 2003, to perform the inspections and removals required 
by this AD. Approval of incorporation by reference from the Office 
of the Federal Register is pending.

Related Information

    (k) None.

    Issued in Burlington, Massachusetts, on November 12, 2003.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 03-28739 Filed 11-17-03; 8:45 am]
BILLING CODE 4910-13-P