
[Federal Register Volume 75, Number 129 (Wednesday, July 7, 2010)]
[Proposed Rules]
[Pages 38943-38945]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-16515]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0672; Directorate Identifier 2010-NM-047-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas Corporation Model DC-
10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10-40, and DC-10-40F 
Airplanes

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 
certain Model DC-10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10-
40, and DC-10-40F airplanes. This proposed AD would require installing 
a support bracket and coupler on the left and right wing-to-fuselage 
transition, and metallic overbraid on the left and right leading edge 
wire assembly. This proposed AD results from fuel system reviews 
conducted by the manufacturer, as well as reports that the fuel 
quantity system was affected by lightning-induced transients. We are 
proposing this AD to prevent lightning-induced transients to the fuel 
quantity indication system, which could cause voltage levels to go 
beyond original design levels between fuel tank probes and structure, 
and become a potential ignition source at the fuel tank, which, in 
combination with flammable fuel vapors, could result in a fuel tank 
explosion and consequent loss of the airplane.

DATES: We must receive comments on this proposed AD by August 23, 2010.

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 proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-
0001; telephone 206-544-5000, extension 2; fax 206-766-5683; e-mail 
dse.boecom@boeing.com; Internet https://www.myboeingfleet.com. You may 
review copies of the referenced service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington. For information on the availability of this material at the 
FAA, call 425-227-1221.

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 (ACO), 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-2010-0672; 
Directorate Identifier 2010-NM-047-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

    The FAA has examined the underlying safety issues involved in fuel 
tank explosions on several large transport airplanes, including the 
adequacy of existing regulations, the service history of airplanes 
subject to those regulations, and existing maintenance practices for 
fuel tank systems. As a result of those findings, we issued a 
regulation titled ``Transport Airplane Fuel Tank System Design Review, 
Flammability Reduction and Maintenance and Inspection Requirements'' 
(66 FR 23086, May 7, 2001). In addition to new airworthiness

[[Page 38944]]

standards for transport airplanes and new maintenance requirements, 
this rule included Special Federal Aviation Regulation No. 88 (``SFAR 
88,'' Amendment 21-78, and subsequent Amendments 21-82 and 21-83).
    Among other actions, SFAR 88 requires certain type design (i.e., 
type certificate (TC) and supplemental type certificate (STC)) holders 
to substantiate that their fuel tank systems can prevent ignition 
sources in the fuel tanks. This requirement applies to type design 
holders for large turbine-powered transport airplanes and for 
subsequent modifications to those airplanes. It requires them to 
perform design reviews and to develop design changes and maintenance 
procedures if their designs do not meet the new fuel tank safety 
standards. As explained in the preamble to the rule, we intended to 
adopt airworthiness directives to mandate any changes found necessary 
to address unsafe conditions identified as a result of these reviews.
    In evaluating these design reviews, we have established four 
criteria intended to define the unsafe conditions associated with fuel 
tank systems that require corrective actions. The percentage of 
operating time during which fuel tanks are exposed to flammable 
conditions is one of these criteria. The other three criteria address 
the failure types under evaluation: single failures, single failures in 
combination with a latent condition(s), and in-service failure 
experience. For all four criteria, the evaluations included 
consideration of previous actions taken that may mitigate the need for 
further action.
    We have determined that the actions identified in this AD are 
necessary to reduce the potential of ignition sources inside fuel 
tanks, which, in combination with flammable fuel vapors, could result 
in fuel tank explosions and consequent loss of the airplane.
    Also, we received reports that the fuel quantity system was 
affected by lightning- induced transients. The fiberglass leading edge 
fairing at the wing root created an electrical discontinuity in the 
metal shielding provided by the wing structure. As rapidly changing 
lightning currents flow in the leading edge gap region during a nose-
to-wing- tip strike, rapidly changing electromagnetic fields are 
created in the gap region. Boeing investigations have determined that 
these fields cause electrical transients to be inducted indirectly into 
the wiring of the fuel quantity indication system. Installing side 
entry wire braid sleeving on fuel probe wires in the root region of 
each wing will minimize lightning-induced transients to the fuel 
quantity indication system. Such transients could result in voltage 
levels going beyond original design levels between fuel tank probes and 
structure and becoming a potential ignition source for the fuel tank.

Relevant Service Information

    We have reviewed Boeing Service Bulletin DC10-28-262, Revision 1, 
dated June 9, 2010. The service bulletin describes procedures for 
installing a support bracket and coupler on the left and right wing-to-
fuselage transition, and installing metallic overbraid on the left and 
right wing leading edge wire assemblies.

FAA's Determination and Requirements of This Proposed AD

    We are proposing this AD because we evaluated all relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of these same type 
designs. This proposed AD would require accomplishing the actions 
specified in the service information described previously.

Costs of Compliance

    We estimate that this proposed AD would affect 61 airplanes of U.S. 
registry. We also estimate that it would take about 28 work-hours per 
product to comply with this proposed AD. The average labor rate is $85 
per work-hour. Required parts would cost about $999 per product. Based 
on these figures, we estimate the cost of this proposed AD to the U.S. 
operators to be $206,119, or $3,379 per product.

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), 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.
    You can find our regulatory evaluation and the estimated costs of 
compliance in the AD Docket.

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

    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 AD:

McDonnell Douglas Corporation: Docket No. FAA-2010-0672; Directorate 
Identifier 2010-NM-047-AD.

Comments Due Date

    (a) We must receive comments by August 23, 2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to McDonnell Douglas Corporation Model DC-
10-10, DC-10-10F, DC-10-30, DC-10-30F (KDC-10), DC-10-40, and DC-10-
40F airplanes, certificated in any category, as identified in Boeing 
Service Bulletin DC10-28-262, Revision 1, dated June 9, 2010.

Subject

    (d) Air Transport Association (ATA) of America Code 28: Fuel.

[[Page 38945]]

Unsafe Condition

    (e) This AD results from fuel system reviews conducted by the 
manufacturer. The Federal Aviation Administration is issuing this AD 
to prevent lightning-induced transients to the fuel quantity 
indication system, which could cause voltage levels to go beyond 
original design levels between fuel tank probes and structure and 
become a potential ignition source at the fuel tank, which, in 
combination with flammable fuel vapors, could result in a fuel tank 
explosion and consequent loss of the airplane.

Compliance

    (f) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Installation

    (g) Within 60 months after the effective date of this AD, 
install a support bracket and coupler on the left and right wing-to-
fuselage transition, and metallic overbraid on the left and right 
leading edge wire assembly, in accordance with the Accomplishment 
Instructions of Boeing Service Bulletin DC10-28-262, Revision 1, 
dated June 9, 2010.

Installation According to Previous Issue of Service Bulletin

    (h) Installing a support bracket and coupler on the left and 
right wing-to-fuselage transition, and metallic overbraid on the 
left and right leading edge wire assembly, is also acceptable for 
compliance with the requirements of paragraph (g) of this AD if done 
before the effective date of this AD in accordance with the 
Accomplishment Instructions of Boeing Service Bulletin DC10-28-262, 
dated January 6, 2010.

Alternative Methods of Compliance (AMOCs)

    (i)(1) The Manager, Los Angeles Aircraft Certification Office, 
FAA, has the authority to approve AMOCs for this AD, if requested 
using the procedures found in 14 CFR 39.19. Send information to 
ATTN: Samuel Lee, Aerospace Engineer, Propulsion Branch, ANM-140L, 
FAA, Los Angeles Aircraft Certification Office (ACO), 3960 Paramount 
Boulevard, Lakewood, California 90712-4137; telephone (562) 627-
5262; fax (562) 627-5210.
    (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 principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.

    Issued in Renton, Washington on June 29, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-16515 Filed 7-6-10; 8:45 am]
BILLING CODE 4910-13-P


