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[Federal Register Volume 77, Number 41 (Thursday, March 1, 2012)]
[Rules and Regulations]
[Pages 12444-12448]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-4747]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0982; Directorate Identifier 2011-NE-09-AD; 
Amendment 39-16954; AD 2012-03-12]
RIN 2120-AA64

Airworthiness Directives; General Electric Company (GE) Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for all GE 
CF6-80C2 model turbofan engines, including engines marked on the engine 
data plate as CF6-80C2B7F1. This AD was prompted by a report of a 
supplier shipping a batch of nonconforming No. 3 bearing packings that 
had incorrect cooling holes and by subsequent reports of nonconforming 
No. 3 bearing packings being installed on engines in service. This AD 
requires a one-time inspection of the No. 3 bearing packing for an 
incorrect cooling hole size and, if it is found nonconforming, removing 
the packing and removing certain engine rotating life-limited parts 
(LLPs), if they were operated with unacceptable rotor bore cooling flow 
for a specified number of cycles. We are issuing this AD to prevent an 
uncontained failure of the high-pressure compressor (HPC) rotor or the 
low-pressure turbine (LPT) rotor, or both, which could cause damage to 
the airplane.

DATES: This AD is effective April 5, 2012. The Director of the Federal 
Register approved the incorporation by reference of certain 
publications listed in the AD as of April 5, 2012.

ADDRESSES: For service information identified in this AD, contact GE 
Aviation, M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215; phone: 
513-552-3272; email: geae.aoc@ge.com. You may review copies of the 
referenced 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 AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (phone: 800-647-5527) is Document Management Facility, 
U.S. Department of Transportation, Docket Operations, M-30, West 
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Tomasz Rakowski, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238-7735; 
fax: 781-238-7199; email: tomasz.rakowski@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM published in the Federal Register on October 18, 2011 (76 FR 
64291). That NPRM proposed to require a one-time inspection of the No. 
3 bearing packing for an incorrect cooling hole size and, if it is 
found nonconforming, removing the packing and removing certain engine 
rotating LLPs, if they were operated with the wrong packing for a 
specified number of cycles.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
and the FAA's response to each comment.

Support for the NPRM as Written

    Commenters the Boeing Company and Federal Express support the NPRM 
as written.

Request To Correct Part Number

    Commenters GE and Delta Airlines (Delta) indicated that the part 
number noted in the Discussion section of the NPRM (76 FR 64291, 
October 18, 2011) was incorrect and should be ``1471M25P04'' rather 
than ``1292M70P04'' as listed in the NPRM.
    We agree. However, the Applicability section of the final rule is 
correct. We did not change the AD.

Request To Clarify Incorrect Shipping Versus Installing Wrong Seal

    Commenter Lufthansa Technik AG (Lufthansa) asked that we state more 
clearly the difference between the issues of packings shipped in a 
batch of nonconforming parts and nonconforming packings installed in 
engines in service.
    We disagree. The AD sufficiently describes the difference between 
nonconforming packings shipped by the supplier and those in service. We 
did not change the AD.

Request To Correct Cost

    Commenter Lufthansa suggested that the cost of compliance estimate 
in the NPRM covers only the cost of shipped nonconforming parts and 
does not include the cost of replacing nonconforming packings that are 
installed in engines in service. Lufthansa also noted that the 
installed parts are covered by a different service bulletin and are not 
covered by warranty.
    We disagree. Our cost estimate covers the inspection and installed 
parts and is independent of any possible warranty coverage. We did not 
change the AD.

Request To Update GE Service Bulletin (SB) Reference

    Commenter Lufthansa requested that we provide full instructions for 
compliance for engine models CF6-80C2L1F and CF6-80C2K1F. Lufthansa 
noted that neither the NPRM (76 FR 64291, October 18, 2011) nor GE SB 
CF6-80C2 S/B 72-1405 provide enough information for these engines to 
comply with the proposed rule. Lufthansa requested that we refer to 
Revision 01 of GE SB CF6-80C2 S/B 72-1405 rather than to the original 
version.
    We agree. We changed the AD by updating the GE service bulletin 
references in the AD to GE SB CF6-

[[Page 12445]]

80C2 S/B 72-1405, Revision 01, dated December 16, 2011.

Request To Revise Cost of Compliance Estimate

    Commenter Atlas Air requested that we revise the cost estimate by 
including cost to replace LLPs.
    We agree. We revised the cost of compliance section in the AD to 
include our estimate for the total fleet replacement cost of LLPs with 
unacceptable cooling flows.

Request for a Cut-Off Date

    Commenter Presidential Flights requested that we specify a date 
after which the batch of non-conforming No. 3 bearing packings with 
incorrect cooling holes was supplied, and that we limit applicability 
to engines that had a shop visit after this specified date. Commenter 
Japan Airlines requested that the AD not apply to engines with a last 
shop visit prior to November 30, 2009, if there have not been reports 
of non-conforming packings for these engines. Commenter Atlas Air 
commented that applicability should only apply to engines with packings 
from the affected batch of nonconforming parts shipped from a supplier.
    We do not agree. The AD applies to all CF6-80C2 engines, regardless 
of the date of the last shop visit, the service location, or the engine 
serial number. The explanation for inspecting the entire fleet is 
provided in the Discussion section of the NPRM (76 FR 64291, October 
18, 2011). We did not change the AD.

Request To Limit AD by Engine Serial Number

    Commenter Atlas Air also asked that applicability be changed to 
specific affected engine serial numbers. Commenter TES Aviation Group 
requested clarification regarding whether the AD applied only to 
engines with certain serial numbers or maintained in certain service 
locations.
    We disagree. The AD applies to all CF6-80C2 engines, regardless of 
engine serial number or last service location. We did not change the 
AD.

Request Regarding Shop Visit

    Commenter GE requested that the applicability be changed to apply 
to only those engines that have had a shop visit where the fan was 
removed from the engine core and GE SB CF6-80C2 S/B 72-1405 was not 
completed during or since that visit. GE indicated that no new 
production engines are affected by the nonconformance and engines that 
already complied with the GE SB CF6-80C2 S/B 72-1405 shop inspection 
have accomplished the requirements of the proposed rule.
    We disagree. Excluding all engines that have not yet had a shop 
visit where the fan was removed from the core leaves an engine 
population in service that might be susceptible to installation of the 
nonconforming packing. We did not change the AD.

Credit for Previous Inspection

    Commenter All Nippon Airways (ANA) asked that credit be given to 
engines inspected in accordance with GE SB CF6-80C2 S/B 72-1405 before 
the effective date of this AD.
    We agree. We changed the AD to indicate that a previous inspection 
meets the one-time inspection requirements of this AD.

Request To Add Additional Engine Models for Compliance

    Commenter Lufthansa requested that we include CF6-45/50, CF6-80A, 
and CF6-80E1 engines, as applicable, to the AD.
    We disagree. We have not received reports of nonconforming packing 
installed in any engine other than the CF6-80C2. We did not change the 
AD.

Request To Mandate Compliance of Spare Parts

    An unidentified commenter requested that we mandate compliance of 
spare parts.
    We do not agree. This AD affects assembled engines in service on 
the effective date of the AD. Parts installed in an engine after the 
effective date of this AD must be airworthy per Sec.  43.13 of Title 14 
of the Code of Federal Regulations. Operators may choose to perform 
inspections in accordance with this AD before returning engines from 
shop into service, although these inspections are not required by this 
AD before specified compliance times. In order to avoid confusion, we 
added a prohibition statement, paragraph (i), which does not allow re-
installation of the LLPs removed from service in accordance with this 
AD.

Request To Clarify Terminating Action

    Commenter ANA requested that we clarify the terminating action to 
the AD.
    We disagree. The AD mandates a one-time inspection and disposition. 
Terminating action does not apply. We did not change the AD.

Request To Allow Borescope Inspection (BSI) To Determine Packing 
Configuration

    Eight commenters requested that we approve a BSI to determine the 
No. 3 bearing packing configuration either on-wing or in the shop and 
to determine if further actions are necessary.
    We partially agree. We agree that a BSI may be used to measure 
packing hole diameters to determine acceptable cooling flows. We 
disagree with using a BSI to determine the part number of the packing 
or the need for further actions as a BSI cannot be used to make such a 
determination on all affected engines.
    We changed the AD to allow the one-time No. 3 bearing packing 
inspection to occur at the next shop visit if a successful optional BSI 
is performed within 500 cycles in service (CIS) from the effective date 
of the AD.

Request To Modify Compliance Time

    Commenters GE and Delta requested that we change the compliance 
time of the one-time inspection to be performed at the next shop visit 
in which the fan is separated from the HPC. GE indicated that it has 
not determined that removal from service prior to 5,500 CIS is 
required. GE regards 5,500 CIS as an economic threshold not a hard life 
removal threshold.
    We disagree. We do not agree with unconditional deferral to the 
next shop visit as unacceptable cooling flow could affect the lives of 
the LLPs. We did not change the AD.

Request To Address Fan Frames With Small Cooling Holes

    Commenter Atlas Air asked that the service information incorporated 
by reference be revised to address certain fan frame part numbers with 
small cooling holes. Atlas Air indicated that certain small fan frame 
hole diameters may affect cooling flows, even though the packing 
configuration is determined to provide acceptable flows.
    We do not agree. The cooling flow assessment addressed the worst 
case configuration. Cooling flow acceptability should be determined 
from the packing hole diameter, not the fan frame hole diameter. We did 
not change the AD.

Request for Action for Engines That Have 5,500 CIS Since Last Shop 
Visit

    Six commenters requested that a drawdown schedule be provided for 
engines that have accumulated 5,500 or more CIS since the last engine 
shop visit when the fan was removed from the core. Some of these 
commenters reported that some of their engines were already past 5,500 
CIS since the last engine shop visit in which the fan was removed from 
the core.
    We agree. We changed the AD to require the inspection within 500 
CIS of

[[Page 12446]]

the effective date of this AD for those post-5,500-cycle engines.

Request on LLP Pass/Fail Criteria

    Commenters Air Canada and TES Aviation Group requested that growth 
checks, hardness checks, or calculations be allowed to determine the 
disposition of LLPs affected by the unacceptable cooling flows instead 
of removing the parts from service if they were operated for 5,500 CIS 
or more with a No. 3 bearing packing determined to be ``UNACCEPTABLE 
FLOW.''
    We do not agree. We have no technical substantiation that supports 
pass/fail criteria for determining if LLPs have operated with an 
unacceptable flow packing configuration. We did not change the AD.

Request on LLP Determination

    Commenter Presidential Flight requested that LLP determination be 
based on CIS since first shop visit after supply of the affected batch, 
not the last shop visit because, they noted, an engine may have had 
multiple shop visits since the affected batch of nonconforming packings 
was shipped. Commenters Air Canada, Atlas Air, and TES Aviation Group 
indicated that it is impossible to determine how many cycles the LLPs 
have operated with nonconforming packings, because the packings are not 
serialized or tracked. In addition, the commenters noted that, if an 
engine is inspected and found to have a conforming packing, there is no 
guarantee that a nonconforming packing had not been used on that engine 
between earlier shop visits. Also, the commenters observed that it is 
impossible to estimate the effect on life of the LLPs that had operated 
with a nonconforming packing and were later removed from the engine.
    We do not agree. Installation dates when nonconforming packings 
might have been installed into engines in service are unknown. 
Similarly, engine operation with nonconforming packing cannot be 
determined other than via inspection of the currently installed 
packing. We did not change the AD.

Request for Disposition of LLPs for Unacceptable Flows

    Commenters GE, American Airlines, and Delta requested that we 
provide the requirement for LLP disposition in the case of the cooling 
flows determined not to be ``CORRECT FLOW'' in accordance with GE SB 
CF6-80C2 S/B 72-1405, dated June 30, 2011.
    We agree. Unacceptable cooling flows are now addressed in Revision 
01 of GE SB CF6-80C2 S/B 72-1405, dated December 16, 2011, and GE SB 
CF6-80C2 S/B 72-1427, dated December 16, 2011. Therein, cooling flows 
not affecting the LLPs in the rotors are described as ``acceptable 
flow.'' We revised the AD in paragraph (h) to remove from service those 
LLPs that had been operated for 5,500 CIS or more with unacceptable 
flow and added paragraph (g) to define criteria for acceptable flows 
determined during an optional borescope inspection.

Request To Revise Criteria for Shop Visit

    Commenters GE and KLM Royal Dutch Airlines requested that the 
induction of an engine into a shop solely for a core vibration trim 
balance procedure that requires separation of a major engine flange not 
be considered an engine shop visit. Another commenter, Lufthansa, 
requested that the induction of an engine into a shop solely for the 
removal or replacement of the stage 1 fan disk or the fan forward case 
also not be considered an engine shop visit.
    We partially agree. We agree that the induction of an engine into a 
shop solely for core vibration balance should not be considered an 
engine shop visit for the purposes of this AD, because it does not 
require separation of the fan from the core. We disagree that the 
induction of an engine into a shop solely for removal or replacement of 
the stage 1 fan disk or fan forward case should not be considered an 
engine shop visit for the purposes of this AD, because these procedures 
require maintenance to the fan module.
    We changed the AD to define a shop visit as not including induction 
of an engine into a shop solely for core vibration trim balance 
procedures that require separation of a major engine flange.

Request To Revise Reference to Fan and Core Module

    Commenter Delta requested that we use the phrase ``fan module 
removed from the core module'' instead of ``fan removed from the 
core.''
    We do not agree. The current language is consistent with service 
documents that we incorporate by reference in this AD. We did not 
change the AD.

Explanation of Additional Changes to This AD

    We provided incorrect contact information for GE in the NPRM (76 FR 
64291, October 18, 2011). We have updated the contact information.

Conclusion

    We reviewed all the data presented, considered 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:
     Are consistent with the intent that was proposed in the 
NPRM (76 FR 64291, October 18, 2011) for correcting the unsafe 
condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM (76 FR 64291, October 18, 2011).
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of the AD.

Costs of Compliance

    We estimate that this AD will affect 688 engines installed on 
airplanes of U.S. registry. We also estimate that it will take about 1 
work-hour per engine to perform the borescope inspection, about 1 work-
hour per engine to perform the shop inspection, and 1 work-hour to 
replace the No. 3 bearing packing, if found nonconforming. The average 
labor rate is $85 per work-hour. Required parts cost about $488 per 
engine for the estimated 21 engines that will require new No. 3 bearing 
packing. We estimate that one set of LLPs will need replacement, and 
the total replacement cost is $1,201,200. Based on these figures, we 
estimate the total cost of this AD to U.S. operators to be $1,330,193. 
Our estimate is exclusive of any possible warranty coverage.

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

    This AD will not have federalism implications under Executive Order 
13132. This AD will not have a substantial direct effect on the States, 
on

[[Page 12447]]

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),
    (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, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA 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 (AD):

2012-03-12 General Electric Company (GE): Amendment 39-16954; Docket 
No. FAA-2011-0982; Directorate Identifier 2011-NE-09-AD.

(a) Effective Date

    This AD is effective April 5, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD is applicable to all GE CF6-80C2 model turbofan engines, 
including engines marked on the engine data plate as CF6-80C2B7F1.

(d) Unsafe Condition

    This AD was prompted by a report of a supplier shipping a batch 
of nonconforming No. 3 bearing packings that had an incorrect size 
of cooling holes and by several subsequent reports of nonconforming 
No. 3 bearing packings being installed on engines in service. The 
nonconformance of No. 3 bearing packings will result in incorrect 
high-pressure compressor (HPC) rotor and low-pressure turbine (LPT) 
rotor bore cooling and, if not corrected, could result in a reduced 
parts life of the life-limited rotating parts. We are issuing this 
AD to prevent an uncontained failure of the HPC rotor or the LPT 
rotor, or both, which could cause damage to the airplane.

(e) Compliance

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

(f) One-Time Inspection and Disposition of the No. 3 Bearing Packing

    (1) Perform a one-time inspection of the No. 3 bearing packing. 
Use paragraphs 3.A.(1) through 3.A.(1)(b) of the Accomplishment 
Instructions of GE Service Bulletin (SB) No. CF6-80C2 S/B 72-1405, 
Revision 01, dated December 16, 2011, to do your inspection. Inspect 
as follows:
    (i) Before 5,500 engine cycles-in-service (CIS) since the last 
engine shop visit where the fan was removed from the core, or within 
500 CIS from the effective date of this AD, whichever occurs later; 
or
    (ii) At the next shop visit, if the engine passes an optional 
borescope inspection (BSI) within 500 CIS from the effective date of 
this AD.
    (2) Remove the packing from service before further flight if the 
wrong packing part number (P/N) is found on the engine during the 
inspection of paragraph (f)(1) of this AD.

(g) Optional BSI

    The optional BSI identified in paragraph (f)(1)(ii) of this AD 
must determine an ``ACCEPTABLE FLOW'' packing is installed. Use 
paragraph 3.A, excluding subparagraphs 3.A.(4)(a)6 through 
3.A.(4)(a)9 and 3.A.(4)(b)5, of the Accomplishment Instructions of 
GE SB CF6-80C2 S/B 72-1427, dated December 16, 2011, to do your BSI.

(h) Disposition of Affected Rotating Parts

    Remove the following rotating parts from service, if they were 
operated for 5,500 CIS or more with a packing determined to be an 
``UNACCEPTABLE FLOW'' packing using paragraph 3.A.(1)(c) of the 
Accomplishment Instructions of GE SB CF6-80C2 S/B 72-1405, Revision 
01, dated December 16, 2011:
    (1) HPC rotor stage 10-through-14 spool, any P/N,
    (2) HPC rotor stage 11-through-14 spool, any P/N,
    (3) LPT rotor stage 3 disk, P/N 9373M53P05, and
    (4) LPT rotor stage 4 disk, P/N 9373M54P03.

(i) Installation Prohibition

    After the effective date of this AD, do not install or reinstall 
in any engine any rotating part that has been removed from service 
in accordance with paragraph (h) of this AD.

(j) Definition

    For the purposes of this AD, an engine shop visit is the 
induction of an engine into the shop after the effective date of 
this AD, where the separation of a major engine flange occurs; 
except the following maintenance actions, or any combination, are 
not considered engine shop visits:
    (1) Induction of an engine into a shop solely for removal of the 
compressor top or bottom case for airfoil maintenance or variable 
stator vane bushing replacement.
    (2) Induction of an engine into a shop solely for replacement of 
the turbine rear frame.
    (3) Induction of an engine into a shop solely for replacement of 
the accessory gearbox or transfer gearbox, or both.
    (4) Induction of an engine into a shop solely for core vibration 
trim balance procedure that requires separation of a major engine 
flange.

(k) Credit for Previous Action

    An inspection of the No. 3 bearing packing performed before the 
effective date of this AD using GE SB CF6-80C2 S/B 72-1405 satisfies 
the requirements of paragraph (f)(1) of this AD.

(l) Alternative Methods of Compliance (AMOCs)

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

(m) Related Information

    (1) For more information about this AD, contact Tomasz Rakowski, 
Aerospace Engineer, Engine Certification Office, FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: 781-238-7735; fax: 781-238-7199; email: 
tomasz.rakowski@faa.gov.
    (2) GE SB CF6-80C2 S/B 72-1405, Revision 01, dated December 16, 
2011, and GE SB CF6-80C2 S/B 72-1427, dated December 16, 2011, 
pertain to the subject of this AD. Contact GE Aviation, M/D Rm. 285, 
One Neumann Way, Cincinnati, OH 45215; phone: 513-552-3272; email: 
geae.aoc@ge.com; for a copy of this service information.

(n) Material Incorporated by Reference

    (1) You must use the following service information to do the 
actions required by this AD, unless the AD specifies otherwise. The 
Director of the Federal Register approved the incorporation by 
reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the 
following service information:
    (i) General Electric Company (GE) Service Bulletin (SB) CF6-80C2 
S/B 72-1405, dated June 30, 2011;
    (ii) GE SB CF6-80C2 S/B 72-1405, Revision 01, dated December 16, 
2011; and
    (iii) GE SB CF6-80C2 S/B 72-1427, dated December 16, 2011.
    (2) For service information identified in this AD, contact GE 
Aviation, M/D Rm. 285, One Neumann Way, Cincinnati, OH 45215; phone: 
513-552-3272; email: geae.aoc@ge.com.
    (3) You may review copies of the referenced 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.
    (4) You may also review copies of the service information that 
is incorporated by reference at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at an NARA facility, call 202-741-

[[Page 12448]]

6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

    Issued in Burlington, Massachusetts, on February 7, 2012.
Peter A. White,
Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-4747 Filed 2-29-12; 8:45 am]
BILLING CODE 4910-13-P
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