[Federal Register Volume 72, Number 35 (Thursday, February 22, 2007)]
[Proposed Rules]
[Pages 7939-7941]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-2975]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-27302; Directorate Identifier 2006-NM-273-AD]
RIN 2120-AA64


Airworthiness Directives; McDonnell Douglas DC-10-30 and DC-10-
30F (KC-10A and KDC-10) Airplanes

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 certain McDonnell Douglas DC-10-30 and DC-10-30F (KC-10A and KDC-
10) airplanes. This proposed AD would require installing Teflon 
sleeving around the fuel pump wire harness inside the conduit in the 
aft supplemental fuel tank. This proposed AD results from fuel system 
reviews conducted by the manufacturer. We are proposing this AD to 
prevent 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.

DATES: We must receive comments on this proposed AD by April 9, 2007.

ADDRESSES: Use one of the following addresses to submit comments 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: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, 
Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, Long Beach Division, 3855 
Lakewood Boulevard, Long Beach, California 90846, Attention: Data and 
Service Management, Dept. C1-L5A (D800-0024), for the service 
information identified in this proposed AD.

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 submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``FAA-2007-
27302; Directorate Identifier 2006-NM-273-AD'' at the beginning 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 
that 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 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 Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the Docket Management System 
receives them.

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,

[[Page 7940]]

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 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 proposed 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.
    We have received a report indicating that fuel leaked from the No. 
1 main fuel tank boost pump electrical conduit into the fuel shroud 
drain system, on a Model DC-10-30 airplane. The airplane had 
accumulated about 25,000 total flight hours. Investigation revealed 
that electrical arcing between chafed wiring and the inside of the 
conduit wall caused a hole in the conduit. Fuel then leaked into the 
conduit through the hole from the fuel tank. This condition, if not 
prevented, could result in 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.

Relevant Service Information

    We have reviewed McDonnell Douglas DC-10 Service Bulletin 24-128, 
dated January 19, 1984. The service bulletin describes procedures for 
installing Teflon sleeving around the fuel pump wire harness inside the 
conduit in the aft supplemental fuel tank. Accomplishing the actions 
specified in the service information is intended to adequately address 
the unsafe condition.

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 
proposed AD, which would require accomplishing the actions specified in 
the service information described previously, except as discussed under 
``Difference Between the Proposed AD and Service Bulletin.''

Difference Between the Proposed AD and Service Bulletin

    The service bulletin recommends accomplishing the modification 
within 34,000 flight hours after installing the supplemental fuel tank. 
When the service bulletin was issued in 1984, we did not have a safety 
concern that warranted AD action. However, the service bulletin was re-
evaluated as part of the SFAR 88 review activity. We determined that AD 
action is warranted. From that review, we also determined that the 
recommended compliance time should be re-examined. Boeing subsequently 
recommended a 60-month compliance time, which is consistent with the 
compliance time recommended in similar Boeing service bulletins. In 
developing an appropriate compliance time for this AD, we considered 
the typical utilization of the affected airplanes, the degree of 
urgency associated with the subject unsafe condition, and the time 
necessary to perform the modification (2 hours). In light of all of 
these factors, we find that a 60-month compliance time represents an 
appropriate interval of time for affected airplanes to continue to 
operate without compromising safety.

Costs of Compliance

    There are about 5 airplanes of the affected design in the worldwide 
fleet. This proposed AD would affect about 5 airplanes of U.S. 
registry. The proposed actions would take about 2 work hours per 
airplane, at an average labor rate of $80 per work hour. The cost of 
required parts is negligible. Based on these figures, the estimated 
cost of the proposed AD for U.S. operators is $800, or $160 per 
airplane.

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.

[[Page 7941]]

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-2007-27302; Directorate Identifier 
2006-NM-273-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by April 9, 
2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to McDonnell Douglas Model DC-10-30 and DC-
10-30F (KC-10A and KDC-10) airplanes, certificated in any category; 
as identified McDonnell Douglas DC-10 Service Bulletin 24-128, dated 
January 19, 1984.

Unsafe Condition

    (d) This AD results from fuel system reviews conducted by the 
manufacturer. We are issuing this AD to prevent 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.

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.

Modification

    (f) Within 60 months after the effective date of this AD, 
install Teflon sleeving around the fuel pump wire harness inside the 
conduit in the aft supplemental fuel tank, in accordance with the 
Accomplishment Instructions of McDonnell Douglas DC-10 Service 
Bulletin 24-128, dated January 19, 1984.

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) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

    Issued in Renton, Washington, on February 13, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-2975 Filed 2-21-07; 8:45 am]
BILLING CODE 4910-13-P