
[Federal Register: April 7, 2008 (Volume 73, Number 67)]
[Proposed Rules]               
[Page 18719-18720]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr07ap08-12]                         

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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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[[Page 18719]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0403; Directorate Identifier 2007-NM-166-AD]
RIN 2120-AA64

 
Airworthiness Directives; McDonnell Douglas Model MD-11 and MD-
11F Airplanes Equipped With General Electric CF6-80C2 Series Engines

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

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain McDonnell Douglas Model MD-11 and MD-11F airplanes. This 
proposed AD would require revising the airplane flight manual to advise 
the flightcrew to use certain procedures during descent in certain 
icing conditions. This proposed AD results from reports of several in-
flight engine flameouts, including multiple dual engine flameout 
events, in ice-crystal icing conditions. We are proposing this AD to 
ensure that the flightcrew has the proper procedures to follow in 
certain icing conditions. These certain icing conditions could cause a 
multiple engine flameout during flight without the ability of the 
engines to be relit, and consequent forced landing of the airplane.

DATES: We must receive comments on this proposed AD by May 22, 2008.

ADDRESSES: You may send comments 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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, 
Long Beach, California 90846, Attention: Data and Service Management, 
Dept. C1-L5A (D800-0024).

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 proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Samuel Lee, Aerospace Engineer, 
Propulsion Branch, ANM-140L, FAA, Los Angeles Aircraft Certification 
Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; 
telephone (562) 627-5262; fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0403; 
Directorate Identifier 2007-NM-166-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 indicating that there have been six (two 
dual) engine flameout events on McDonnell Douglas Model MD-11 
airplanes, in ice-crystal icing conditions during descent. These 
airplanes were equipped with General Electric (GE) CF6-80C2 series 
engines. Each flameout was in or near convective weather with ice-
crystal icing; this type of icing does not appear on radar due to its 
low reflectivity, and neither the airplane ice detectors nor visual 
indications indicate the presence of this type of icing conditions. 
Therefore, it is usually undetected by the flightcrew. These conditions 
can cause ice crystals to accumulate in the core flow path of the 
engine during low-power conditions, such as idle or idle descent. The 
accumulated ice sheds during throttle increase and is ingested into the 
engine, causing the combustor to flameout resulting in an in-flight 
flameout and potential damage to the high pressure compressor due to 
ice impact.
    Activating the anti-ice system increases the flameout margin and 
reduces the potential for multiple engine flameouts by increasing bleed 
flow and engine idle speed. However, in some of the subject engine 
flameouts, the anti-ice was already on when the engines flamed out. In 
each event, the engines relit and continued to operate normally for the 
remainder of the flight. Having the igniters on is necessary to ensure 
that the engine will relight quickly.
    This condition, if not corrected, could result in a multiple engine 
flameout during flight without the ability of the engines to be relit, 
and consequent forced landing of the airplane.

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 airplanes 
of this same type design. For this reason, we are proposing this AD, 
which would require revising the airplane flight manual (AFM) to advise 
the flightcrew to use certain procedures during descent in certain 
icing conditions.

[[Page 18720]]

Interim Action

    We consider this proposed AD interim action. If final action is 
later identified, we might consider further rulemaking then.

Costs of Compliance

    There are about 118 airplanes of the affected design in the 
worldwide fleet. The following table provides the estimated costs for 
U.S. operators to comply with this proposed AD.

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                        Number of U.S.-
                      Action                           Work hours     Average labor        Parts           Cost per        registered       Fleet cost
                                                                      rate per hour                        airplane        airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
AFM revision......................................               1              $80               $0              $80               70           $5,600
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 
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. 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 regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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

    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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

McDonnell Douglas: Docket No. FAA-2008-0403; Directorate Identifier 
2007-NM-166-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by May 22, 
2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to McDonnell Douglas Model MD-11 and MD-11F 
airplanes, certified in any category, equipped with General Electric 
CF6-80C2 series engines.

Unsafe Condition

    (d) This AD results from reports of several in-flight engine 
flameouts, including multiple dual engine flameout events, in ice-
crystal icing conditions. We are issuing this AD to ensure that the 
flightcrew has the proper procedures to follow in certain icing 
conditions. These certain icing conditions could cause a multiple 
engine flameout during flight without the ability of the engines to 
be relit, and consequent forced landing of 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.

Airplane Flight Manual (AFM) Revision

    (f) Within 14 days after the effective date of this AD, revise 
the Limitations Section of the McDonnell Douglas MD-11/MD-11F AFM to 
include the following statement. This may be done by inserting a 
copy of this AD into the AFM.
    ``Prior to reducing thrust for descent in visible moisture when 
TAT is 6 [deg]C and below, the ENG IGN OVRD switch and the ENG, 
WING, and TAIL ANTI-ICE switches must be placed in the ON 
position.''

    Note 1: When a statement identical to that in paragraph (f) of 
this AD has been included in the general revisions of the AFM, the 
general revisions may be inserted into the AFM, and the copy of this 
AD may be removed from the AFM.

Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Los Angeles Aircraft Certification Office, 
FAA, has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.

    Issued in Renton, Washington, on March 27, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E8-7151 Filed 4-4-08; 8:45 am]

BILLING CODE 4910-13-P
