AD 2007-05-14

[Federal Register Volume 72, Number 42 (Monday, March 5, 2007)]
[Rules and Regulations]
[Pages 9662-9666]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 07-986]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-23871; Directorate Identifier 2006-NE-01-AD; 
Amendment 39-14975; AD 2007-05-14]
RIN 2120-AA64


Airworthiness Directives; General Electric Company (GE) CF6-80C2 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for GE 
CF6-80C2 series turbofan engines. This AD requires replacing certain 
installed part number (P/N) and serial number (SN) cast titanium weld-
repaired forward engine mount platforms and cast titanium forward mount 
yokes, with a forged titanium or a non-welded cast titanium part. This 
AD results from the discovery of cracks, in a weld-repaired area on a 
forward engine mount platform and a forward engine mount yoke, found 
during a fluorescent penetrant inspection (FPI). These parts were weld-
repaired during manufacture. We are issuing this AD to prevent cracks 
in the forward engine mount platform and forward engine mount yoke that 
could result in possible separation of the engine from the airplane.

DATES: This AD becomes effective April 9, 2007.

ADDRESSES: You can get the service information identified in this 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 on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a> 
or in Room PL-401 on the plaza level of the Nassif Building, 400 
Seventh Street, SW., Washington, DC.

FOR FURTHER INFORMATION CONTACT: James Lawrence, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; telephone (781) 238-
7176; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39 
with a proposed AD. The proposed AD applies to GE CF6-80C2 series 
turbofan engines. We published the proposed AD in the Federal Register 
on December 13, 2006 (71 FR 74873). That action proposed to require 
replacing certain installed part number (P/N) and serial number (SN) 
cast titanium weld-repaired forward engine mount platforms and cast 
titanium forward mount yokes, with a forged titanium or a non-welded 
cast titanium part.

Examining the AD Docket

    You may examine the docket that contains the AD, any comments 
received, and any final disposition in person at the Docket Management 
Facility between 9 a.m. and 5 p.m., Monday through Friday, except 
Federal holidays. The Docket Office (telephone (800) 647-5227) is 
located on the plaza level of the Department of Transportation Nassif 
Building at the street address stated in ADDRESSES.

[[Page 9663]]

Comments will be available in the AD docket shortly after the DMS 
receives them.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comments received.

Add Airbus A310 and MD-11 Airplanes to the Applicability

    Commenters from Lufthansa Technik, KLM Royal Dutch Airlines, Airbus 
and Alitalia state that this AD is also applicable to the engines 
installed in the A310 and MD-11 airplanes. We agree. We inadvertently 
omitted the Airbus A310 and MD-11 airplanes from the Applicability 
section of the proposed rule. These airplanes are included in the 
Applicability section of the AD.

Reference GE Service Bulletins

    Commenters from Lufthansa Technik, KLM Royal Dutch Airlines, Airbus 
and Alitalia also state that because the AD mandates requirements 
contained in GE Service Bulletins, CF6-80C2 S/B 72-1206 and CF6-80C2 S/
B 72-1207, the FAA should reference the service bulletins in the final 
rule. We agree. The service bulletins' accomplishment instructions 
contain information such as applicable Aircraft Maintenance Manual 
sections that would clarify requirements of the AD. A reference to the 
service bulletins is included in the Related Information Section of the 
AD.

Location of Weld Repair

    Representatives from Lufthansa Technik and KLM Royal Dutch Airlines 
note that paragraph (h) of the applicability section identifies a weld 
repair in a redundant area of the yoke, but Table 3 identifies the weld 
repair in a non-redundant area of the yoke. The FAA needs to correct 
this inconsistency in the final rule. We agree and have changed the 
heading of Table 3 to read, ``Weld-Repaired Forward Engine Mount Yokes 
Requiring Replacement That Have a Weld Repair in a Redundant Area of 
the Yoke.''

Conclusion

    We have carefully reviewed the available data, including the 
comments received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    There are 25 engines in service that contain the substandard 
forward engine mount platforms and 59 engines in service that contain 
the substandard forward engine mount yokes. We estimate that this 
proposed AD would affect 84 CF6-80C2 engines installed on airplanes of 
U.S. registry. We estimate that it would take 34 work-hours per engine 
to replace the weld-repaired cast titanium forward engine mount 
platforms and the weld-repaired cast titanium forward engine mount 
yokes. The average labor rate is $80 per work-hour. Required forward 
engine mount parts would cost about $12,168 per engine. Required 
forward engine mount yoke parts would cost about $39,560 per engine. 
Based on these figures, we estimate the total cost of the proposed AD 
to U.S. operators to be $2,866,720.

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 AD will not have federalism 
implications under Executive Order 13132. This AD will 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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and
    (3) 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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. 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, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2007-05-14 General Electric Company: Amendment 39-14975. Docket No. 
FAA-2006-23871; Directorate Identifier 2006-NE-01-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective April 9, 
2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to the following General Electric Company 
(GE) turbofan engines with cast titanium assembly engine mount 
platforms part numbers (P/Ns) 1292M13G06, 1301M28G08, 1459M70G07, 
and 1846M24G04 and cast titanium assembly engine mount yokes P/Ns 
9383M43G14 and 9383M43G16 installed.
CF6-80C2A1
CF6-80C2A2
CF6-80C2A3
CF6-80C2A5
CF6-80C2A8
CF6-80C2A5F
CF6-80C2B1
CF6-80C2B2
CF6-80C2B4
CF6-80C2B6
CF6-80C2B1F
CF6-80C2B2F
CF6-80C2B4F
CF6-80C2B5F
CF6-80C2B6F
CF6-80C2B6FA
CF6-80C2B7F
CF6-80C2B8F
CF6-80C2D1F

    These engines are installed on, but not limited to, Boeing 747, 
Boeing 767, MD-11 and Airbus A300-600 and A310 airplanes.

[[Page 9664]]

Unsafe Condition

    (d) This AD results from the discovery of cracks in a forward 
engine mount platform and a forward engine mount yoke found during 
fluorescent penetrant inspection (FPI). We are issuing this AD to 
prevent cracks in the forward engine mount platform and forward 
engine mount yoke that could result in possible separation of the 
engine from 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.

P/N and SN Weld-Repaired Forward Engine Mount Platforms and Forward 
Engine Mount Yokes Requiring Replacement

    (f) Table 1 of this AD lists the P/Ns and serial numbers (SNs) 
of the weld-repaired forward engine mount platforms that have a weld 
repair in a non-redundant area of the mount and must be replaced.

    Table 1.--Weld-Repaired Forward Engine Mount Platforms Requiring
Replacement That Have a Weld Repair in a Non-Redundant Area of the Mount
------------------------------------------------------------------------
                  P/Ns                                 SNs
------------------------------------------------------------------------
1292M13G06 or 1846M24G04                 WACHH228
                                         WACHH254
                                         WACHH285
                                         WACHH290
                                         WACHH292
                                         WACHH295
                                         WACHH299
                                         WACHH384
                                         WACHH427
                                         WACHH440
                                         WACHH604
1301M28G08.............................  WACAR292
                                         WACAR354
------------------------------------------------------------------------

    (g) Table 2 of this AD lists the P/Ns and SNs of the weld-
repaired forward engine mount platforms that have a weld repair in a 
redundant area of the mount. Because it is impossible to detect 
whether the mount is operating on the redundant feature, each of 
these mounts must be replaced. The compliance time for mounts in 
this category can be longer than for the mounts listed in Table 1 of 
this AD.

    Table 2.--Weld-Repaired Forward Engine Mount Platforms Requiring
  Replacement That Have a Weld Repair in a Redundant Area of the Mount
------------------------------------------------------------------------
                  P/Ns                                 SNs
------------------------------------------------------------------------
1292M13G06 or 1846M24G04                 WACHH173
                                         WACHH189
                                         WACHH274
                                         WACHH278
                                         WACHH314
                                         WACHH325
                                         WACHH486
1301M28G08.............................  WACAR294
                                         WACAR304
                                         WACAR353
                                         WACAR372
1459M70G07.............................  MTXT1282
------------------------------------------------------------------------

    (h) Table 3 of this AD lists the P/Ns and SNs of the weld-
repaired forward engine mount yokes that have a weld repair in a 
redundant area of the yoke. Because it is impossible to detect 
whether the mount yoke is operating on the redundant feature, each 
of these mount yokes must be replaced. The compliance time for 
mounts in this category can be longer than for the mounts listed in 
Table 1 of this AD.

Table 3.--Weld-Repaired Forward Engine Mount Yokes Requiring Replacement
         That Have a Weld Repair in a Redundant Area of the Yoke
------------------------------------------------------------------------
                  P/Ns                                 SNs
------------------------------------------------------------------------
9383M43G14.............................  WACV0388
                                         WACV0394
                                         WACV0405
                                         WACV0406
                                         WACV0477
                                         WACV0498
                                         WACV0529
                                         WACV0556
                                         WACV0579
                                         WACV0581
                                         WACV0582
                                         WACV0600
                                         WACV0605
                                         WACV0617
                                         WACV0625
                                         WACV0627
                                         WACV0633
                                         WACV0645
                                         WACV0683
                                         WACV0703
                                         WACV0733
                                         WACV0737
                                         WACV0759
                                         WACV0775
                                         WACV0791
                                         WACV0799
                                         WACV0875
                                         WACV0883
                                         WACV0885
                                         WACV0909
                                         WACV1097
                                         WACV1615
                                         WACV1713
                                         WACV1753
                                         WACV1797
                                         WACV1867
                                         WACV1987
                                         WACV2131
                                         WACV2159
                                         WACV2185
                                         WACV2343
                                         WACV2511
                                         WACV2695
                                         WACV2707
                                         WACV2881
                                         WACV2899
9383M43G16.............................  WACV0511
                                         WACV0515
                                         WACV0518
                                         WACV0540
                                         WACV0542
                                         WACV0571
                                         WACV0689
                                         WACV0721
                                         WACV0727
                                         WACV0730
                                         WACV0786
                                         WACV0816
                                         WACV0954
------------------------------------------------------------------------

    (i) GE advises that forward engine mount platform, P/Ns 
1292M13G06 and 1846M24G04, are the same, except that P/N 1846M24G04 
incorporates a previously approved field rework. This rework allows 
the thrust pin hole in the forward engine mount platform to be bored 
out to accept installation of an oversized thrust pin. GE cannot 
identify which SN goes with which P/N, but all SNs are affected.

Welded Cast Titanium Forward Engine Mount Platform and Forward Engine 
Mount Yoke Removal

    (j) If the P/N and SN of the forward engine mount platform 
listed in Table 1 and Table 2 and the forward engine mount yoke 
listed in Table 3 of this AD are not installed on the engine, no 
further action is necessary.
    (k) If the P/N and SN of the forward engine mount platform 
listed in Table 1 of this AD is installed on the engine:
    (1) Remove the forward engine mount platform from the engine 
within 500 cycles or 6 months, after the effective date of this AD, 
whichever occurs first.
    (2) Information for removal of the forward engine mount platform 
from the engine can be found in the CF6-80C2 Engine Manual, 72-00-
01, Disassembly.
    (l) If the P/N and SN of the forward engine mount platform 
listed in Table 2 of this AD is installed on the engine:
    (1) Remove the forward engine mount platform at the next shop 
visit, or within 4,800 cycles after the effective date of this AD, 
whichever occurs first.
    (2) Information for removal of the forward engine mount yoke can 
be found in the CF6-80C2 Engine Manual, 72-00-01, Disassembly.
    (m) If the P/N and SN of the forward engine mount yoke listed in 
Table 3 of this AD is installed on the engine:
    (1) Remove the forward engine mount yoke at the next shop visit, 
or within 4,800 cycles after the effective date of this AD, 
whichever occurs first.

[[Page 9665]]

    (2) Information for removal of the forward engine mount yoke can 
be found in the CF6-80C2 Engine Manual, 72-00-01, Disassembly.
    (n) Replace the affected forward engine mount platform and or 
the affected forward engine mount yoke with a non-weld-repaired cast 
titanium forward engine mount platform and or the forward engine 
mount yoke or a forged titanium forward engine mount platform or a 
forged titanium forward engine mount yoke.
    (o) Information for installing the forward engine mount platform 
and forward engine mount yoke can be found in the CF6-80C2 Engine 
Manual, 72-00-01, Assembly.
    (p) Location of the forward engine mount platform and forward 
engine mount yoke and SN are illustrated in the following Figure 1.
BILLING CODE 4910-13-P
[GRAPHIC] [TIFF OMITTED] TR05MR07.000

    (q) After the effective date of this AD, do not install a weld-
repaired, cast forward engine mount platform or a weld-repaired, 
cast forward engine mount yoke in any engine.

Alternative Methods of Compliance

    (r) 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

    (s) Contact James Lawrence, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; telephone (781) 238-
7176; fax (781)

[[Page 9666]]

238-7199 for more information about this AD.
    (t) General Electric Company Service Bulletins CF6-80C2 S/B 72-
1206, dated December 23, 2005, and CF6-80C2 S/B 72-1207, Revision 
01, dated July 05, 2006, pertain to the subject of this AD.

    Issued in Burlington, Massachusetts, on February 27, 2007.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 07-986 Filed 3-2-07; 8:45 am]
BILLING CODE 4910-13-P