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[Federal Register Volume 72, Number 37 (Monday, February 26, 2007)]
[Proposed Rules]
[Pages 8309-8311]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-3165]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-27334; Directorate Identifier 2006-NM-279-AD]
RIN 2120-AA64

Airworthiness Directives; McDonnell Douglas Model DC-8-33, -42, 
and -43 Airplanes; Model DC-8-50 Series Airplanes; Model DC-8F-54 and -
55 Airplanes; Model DC-8-60 Series Airplanes; Model DC-8-60F Series 
Airplanes; Model DC-8-72 Airplanes; and Model DC-8-70F Series 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 airplanes described previously. This 
proposed AD would require installing bonding jumpers to the airplane 
wing structure from the fuel system in-line electrical solenoid valves 
along the left and right wing front spar. This proposed AD results from 
fuel system reviews conducted by the manufacturer. We are proposing 
this AD to prevent point-of-contact arcing or filament heating damage 
in the fuel lines that could create a potential ignition source, which, 
in combination with flammable fuel vapors, could cause a fuel tank 
explosion and consequent loss of the airplane.

DATES: We must receive comments on this proposed AD by April 12, 2007.

[[Page 8310]]

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-
27334; Directorate Identifier 2006-NM-279-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, 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 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 system in-line 
solenoid valve installations located in fuel vapor zones along the 
front spar of the left and right wings might not have adequate ground 
paths to dissipate the overcurrent from a lightning-induced high 
voltage transient. This condition, if not corrected, could result in 
point-of-contact arcing or filament heating damage in the fuel lines 
that could create a potential ignition source, which, in combination 
with flammable fuel vapors, could cause a fuel tank explosion and 
consequent loss of the airplane.

Relevant Service Information

    We have reviewed Boeing Service Bulletin DC8-28-091, dated November 
7, 2006. The service bulletin describes procedures for installing 
bonding jumpers to the airplane wing structure from the fuel system in-
line electrical solenoid valves along the left and right wing front 
spar. 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 AD, 
which would require accomplishing the actions specified in the service 
information described previously.

Costs of Compliance

    There are about 216 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 145 airplanes of 
U.S. registry. The following table provides the estimated costs for 
U.S. operators to comply with this proposed AD, at an average labor 
rate of $80 per work hour. The total fleet

[[Page 8311]]

cost is estimated to be between $456,460 and $1,018,770.

                             Estimated Costs
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                                            Work               Cost per
             Airplane  group                hours     Parts    airplane
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1.......................................         8    $2,508      $3,148
2.......................................         9     4,237       4,957
3.......................................        10     6,226       7,026
4.......................................         8     4,473       5,113
5.......................................         6     3,674       4,154
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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-2007-27334; Directorate Identifier 
2006-NM-279-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by April 12, 
2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to McDonnell Douglas Model DC-8-33, -42, and 
-43 airplanes; Model DC-8-51, -52, -53, and -55 airplanes; Model DC-
8F-54 and -55 airplanes; Model DC-8-61, -62, and -63 airplanes; 
Model DC-8-61F, -62F, and -63F airplanes; Model DC-8-72 airplanes; 
and Model DC-8-71F, -72F, and -73F airplanes; certificated in any 
category; as identified in Boeing Service Bulletin DC8-28-091, dated 
November 7, 2006.

Unsafe Condition

    (d) This AD results from fuel system reviews conducted by the 
manufacturer. We are issuing this AD to prevent point-of-contact 
arcing or filament heating damage in the fuel lines that could 
create a potential ignition source, which, in combination with 
flammable fuel vapors, could cause a fuel tank explosion 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.

Installation of Bonding Jumpers

    (f) Within 60 months after the effective date of this AD, 
install bonding jumpers to the airplane wing structure from the fuel 
system in-line electrical solenoid valves along the left and right 
wing front spar, in accordance with the Accomplishment Instructions 
of Boeing Service Bulletin DC8-28-091, dated November 7, 2006.

Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Los Angeles Aircraft Certification Office 
(ACO), 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 16, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-3165 Filed 2-23-07; 8:45 am]
BILLING CODE 4910-13-P
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