

[Federal Register: September 7, 2007 (Volume 72, Number 173)]
[Proposed Rules]               
[Page 51384-51386]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07se07-22]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-29001; Directorate Identifier 2007-NE-36-AD]
RIN 2120-AA64

 
Airworthiness Directives; General Electric Company CF34-8C1/-8C5/
-8C5B1/-8E5/-8E5A1, and CF34-10E Series Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (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) CF34-8C1/-8C5/-8C5B1/-8E5/-8E5A1, and 
CF34-10E series turbofan engines with certain part number (P/N) and 
serial number (SN) fuel metering units (FMU) installed. This proposed 
AD would require a onetime test of the FMU for a miswired (reversed 
polarity) condition of the input wires to the overspeed solenoid. This 
proposed AD results from the discovery of miswired FMU overspeed 
solenoids in the field. We are proposing this AD to prevent the engine 
from failing to shutdown as commanded during an overspeed, leading to 
uncontained engine failure.

DATES: We must receive any comments on this proposed AD by November 6, 
2007.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 

the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov
 and follow the instructions for sending your 

comments electronically.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     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.
    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.

FOR FURTHER INFORMATION CONTACT: Tara Chaidez, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
tara.chaidez@faa.gov; telephone (781) 238-7773; 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-2007-29001; 
Directorate Identifier 2007-NE-36-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://dms.dot.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 
DOT Web site, anyone can find and read the comments in any of our 
dockets, including 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) or you 
may visit http://dms.dot.gov.


Examining the AD Docket

    You may examine the AD docket on the Internet at http://dms.dot.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

[[Page 51385]]

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

    Woodward Governor Company has discovered in the field a miswired 
(reversed polarity) condition of the input wires to the overspeed 
solenoid, on some FMUs. Investigation of FMU manufacturing records 
shows that there is a possibility that a population of FMUs might be 
miswired. If the solenoid is miswired, the engine will fail to shut 
down as commanded. This condition, if not corrected, could result in 
failure of the engine to shutdown as commanded during an overspeed, 
leading to uncontained engine failure.

Relevant Service Information

    We have reviewed and approved the technical contents of GE Service 
Bulletin (SB) No. CF34-8C-AL S/B 73-0030, Revision 1, dated July 19, 
2007, SB No. CF34-8E-AL S/B 73-0015, Revision 1, dated July 19, 2007, 
and SB No. CF34-10E S/B 72-0067, Revision 1, dated July 26, 2007 that 
describe procedures for performing a onetime test of suspect FMUs for a 
miswired (reversed polarity) condition of the input wires to the 
overspeed solenoid.

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. We are proposing this AD, which would require 
a onetime test of suspect FMUs for a miswired (reversed polarity) 
condition of the input wires to the overspeed solenoid. The proposed AD 
would require you to use the service information described previously 
to perform these actions.

Costs of Compliance

    We estimate that this proposed AD would affect 1,055 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 0.25 work-hour per engine to perform the proposed actions, 
and that the average labor rate is $80 per work-hour. We estimate that 
about 2 percent of the inspected solenoids are defective, and it will 
cost about $5,000 to replace each FMU. Based on these figures, we 
estimate the total cost of the proposed AD to U.S. operators to be 
$180,000. Our cost estimate is exclusive of 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

    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, Safety.

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 adding the following new 
airworthiness directive:

General Electric Company: Docket No. FAA-2007-29001; Directorate 
Identifier 2007-NE-36-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by November 6, 
2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to:
    (1) General Electric Company (GE) CF34-8C1/-8C5/-8C5B1/-8E5/-
8E5A1 turbofan engines, with GE fuel metering unit (FMU) part number 
(P/N) 4120T01P02, serial numbers (SNs) WYG94939 through WYGB4222, 
and Woodward Governor FMU Vendor Identification Number (VIN) 8061-
926, SNs 11954378 through 15140071.
    (2) GE CF34-10E series turbofan engines, with GE FMU P/N 
2043M10P05, SNs WYGA3251 through WYGB4085, and Woodward Governor FMU 
VIN 8063-884, SNs 13335695 through 15028283.
    (3) CF34-8C1/-8C5/-8C5B1 turbofan engines are installed on, but 
not limited to, Bombardier Inc. Model CL-600-2C10 (CRJ-700 & -701), 
and CL-600-2D24/-2D15 (CRJ-900) airplanes.
    (4) CF34-8E5/-8E5A1 turbofan engines are installed on, but not 
limited to, Embraer ERJ 170-100/-200 series airplanes.
    (5) CF34-10E series turbofan engines are installed on, but not 
limited to, Embraer ERJ 190-100/-200 series airplanes.

Unsafe Condition

    (d) This AD results from the discovery of miswired FMU overspeed 
solenoids in the field. We are issuing this AD to prevent failure of 
the engine to shutdown as commanded during an overspeed, leading to 
uncontained engine failure.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within 2,200 flight hours after the effective date of 
this AD, but not to exceed 24 months after the effective date of 
this AD, unless the actions have already been done.

Onetime Test of the FMU

    (f) Perform a onetime test of the FMU for a miswired (reversed 
polarity) condition of the input wires to the overspeed solenoid.
    (g) Use paragraph 3A of the Accomplishment Instructions of GE 
Service Bulletin (SB) No. CF34-8C-AL S/B 73-0030, Revision 1, dated 
July 19, 2007, SB No. CF34-8E-AL S/B 73-0015, Revision 1, dated July 
19, 2007, or SB No. CF34-10E S/B 72-0067, Revision 1, dated July 26, 
2007, as applicable, to do the test.
    (h) If the FMU fails the test, remove the FMU.

[[Page 51386]]

Previous Credit

    (i) If you performed the actions specified in paragraphs (f) 
through (h) of this AD, using the inspection procedures in GE SB No. 
CF34-8C-AL S/B 73-0030, dated May 25, 2007, SB No. CF34-8E-AL S/B 
73-0015, dated June 1, 2007, or SB No. CF34-10E S/B 72-0067, dated 
June 7, 2007, before the effective date of this AD, you have 
satisfied the compliance requirements of this AD.

Reporting Requirements

    (j) At the applicable time specified in paragraph (j)(4) or 
(j)(5) of this AD:
    (1) Submit a report of all findings (both positive and negative) 
of the testing required by paragraph (f) of this AD to Customer 
Support Manager, Woodward Governor Company, e-mail: 
Jim.Akers@Woodward.com; telephone (815) 639-5365.

    (2) The report must include date of inspection, serial number of 
FMU, and results of the inspection.
    (3) Under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements contained in this 
AD and has assigned OMB Control Number 2120-0056.
    (4) If the inspection is done after the effective date of this 
AD, submit the report within 10 days after the inspection.
    (5) If the inspection was done before the effective date of this 
AD, submit the report within 10 days after the effective date of 
this AD.

Alternative Methods of Compliance

    (k) 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

    (l) None.
    (m) Contact Tara Chaidez, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
tara.chaidez@faa.gov; telephone (781) 238-7773; fax (781) 238-7199, 

for more information about this AD.

    Issued in Burlington, Massachusetts, on August 28, 2007.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E7-17680 Filed 9-6-07; 8:45 am]

BILLING CODE 4910-13-P
