Document ID: FAA-2014-0521-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: CFM International S.A. Turbofan Engines
Posted Date: 2014-10-02T04:00Z

[Federal Register Volume 79, Number 191 (Thursday, October 2, 2014)]
[Proposed Rules]
[Pages 59467-59468]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-23563]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0521; Directorate Identifier 2014-NE-11-AD]
RIN 2120-AA64

Airworthiness Directives; CFM International S.A. Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
CFM International (CFM) S.A. CFM56-7B series turbofan engines. This 
proposed AD was prompted by a dual engine thrust instability event that 
resulted in the overspeed and in-flight shutdown (IFSD) of one engine. 
This proposed AD would require modification of the engine by removing 
full authority digital engine control (FADEC) software, version 7BV4 or 
earlier, installed in the electronic engine controls (EECs) on CFM56-7B 
engines. We are proposing this AD to prevent a thrust instability 
event, which could lead to overspeed and IFSD of one or more engines, 
loss of thrust control, damage to the engine, and damage to the 
airplane.

DATES: We must receive comments on this proposed AD by December 1, 
2014.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     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.
    For service information identified in this AD, contact CFM 
International Inc., Aviation Operations Center, 1 Neumann Way, M/D Room 
285, Cincinnati, OH 45125; phone: 877-432-3272; fax: 877-432-3329; 
email: geae.aoc@ge.com. You may view this 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 by searching for and locating Docket No. FAA-2014-
0521; 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 proposed AD, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Office (phone: 800-647-5527) is in the ADDRESSES section. Comments will 
be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238-7146; 
fax: 781-238-7199; email: barbara.caufield@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2014-0521; 
Directorate Identifier 2014-NE-11-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We have received reports of dual engine thrust instability events 
on CFM56-7B turbofan engines that resulted in overspeed and IFSD of one 
engine. These resulted from water-borne fuel contamination of the fuel 
supply causing a lag in the response of the control valve in the fuel 
metering unit (FMU). CFM has improved its FADEC software to help 
prevent the lag in the response of the FMU control valve, thereby 
mitigating these thrust instability events. This condition, if not 
corrected, could lead to overspeed and IFSD of one or more engines, 
loss of thrust control, damage to the engine, and damage to the 
airplane.

[[Page 59468]]

Relevant Service Information

    We reviewed CFM Service Bulletin (SB) No. CFM56-7B S/B 73-0203, 
dated June 9, 2014, and CFM SB No. CFM56-7B S/B 73-0204, dated June 9, 
2014. The SBs describe procedures for the introduction of new FADEC 
software for the EECs.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require modification of the engine by 
removing FADEC software, version 7BV4 or earlier, installed in the EECs 
on CFM56-7B engines.

Costs of Compliance

    We estimate that this proposed AD would affect about 2,921 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 1 hour per product to comply with this proposed AD. The 
average labor rate is $85 per hour. Based on these figures, we estimate 
the cost of the proposed AD on U.S. operators to be $248,285.

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 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 this 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),
    (3) Will not affect intrastate aviation in Alaska to the extent 
that it justifies making a regulatory distinction, 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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. Amend Sec.  39.13 by adding the following new airworthiness 
directive (AD):

CFM International S.A.: Docket No. FAA-2014-0521; Directorate 
Identifier 2014-NE-11-AD.

(a) Comments Due Date

    We must receive comments by December 1, 2014.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all CFM International (CFM) S.A. CFM56-7B 
series turbofan engines.

(d) Unsafe Condition

    This AD was prompted by a dual engine thrust instability event 
that resulted in the overspeed and in-flight shutdown (IFSD) of one 
engine. We are issuing this AD to prevent a thrust instability 
event, which could lead to overspeed and IFSD of one or more 
engines, loss of thrust control, damage to the engine, and damage to 
the airplane.

(e) Compliance

    (1) Comply with this AD within the compliance times specified, 
unless already done.
    (2) Within 6 months after the effective date of this AD, modify 
the engine by removing full authority digital engine control (FADEC) 
software, version 7BV4 or earlier, installed in the electronic 
engine controls.

(f) Alternative Methods of Compliance (AMOCs)

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

(g) Related Information

    (1) For more information about this AD, contact Barbara 
Caufield, Aerospace Engineer, Engine Certification Office, FAA, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA 01803; phone: 781-238-7751; fax: 781-238-7199; email: 
barbara.caufield@faa.gov.
    (2) CFM Service Bulletin (SB) No. CFM56-7B S/B 73-0203, dated 
June 9, 2014, and CFM No. SB CFM56-7B S/B 73-0204, dated June 9, 
2014, which are not incorporated by reference in this proposed AD, 
can be obtained from CFM using the contact information in paragraph 
(g)(3) of this proposed AD.
    (3) For service information identified in this proposed AD, 
contact CFM International Inc., Aviation Operations Center, 1 
Neumann Way, M/D Room 285, Cincinnati, OH 45125; phone: 877-432-
3272; fax: 877-432-3329; email: geae.aoc@ge.com.
    (4) You may view this 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.

    Issued in Burlington, Massachusetts, on September 25, 2014.
Ann C. Mollica,
Acting Directorate Manager, Engine & Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2014-23563 Filed 10-1-14; 8:45 am]
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