[Federal Register Volume 70, Number 151 (Monday, August 8, 2005)]
[Proposed Rules]
[Pages 45587-45590]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-15591]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-22032; Directorate Identifier 2005-NM-049-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A300 B4-620, A310-304, 
A310-324, and A310-325 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 Airbus Model A300 B4-620, A310-304, A310-324, and A310-325 
airplanes. This proposed AD would require installing fused adaptors 
between the external wiring harness and the in-tank wiring at the 
connectors on the fuel tank wall of the auxiliary center tank (ACT). 
This proposed AD is prompted by the results of fuel system reviews 
conducted by the manufacturer. We are proposing this AD to prevent an 
ignition source in the ACT, 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 September 7, 
2005.

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 Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, 
France, for service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Tim Backman, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2797; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Include the docket number 
``Docket No. FAA-2005-22032; Directorate Identifier 2005-NM-049-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.

[[Page 45588]]

    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 our 
docket 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 the 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 
recent 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'' (67 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 another 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.
    The Joint Aviation Authorities (JAA) has issued a regulation that 
is similar to SFAR 88. (The JAA is an associated body of the European 
Civil Aviation Conference (ECAC) representing the civil aviation 
regulatory authorities of a number of European States who have agreed 
to co-operate in developing and implementing common safety regulatory 
standards and procedures.) Under this regulation, the JAA stated that 
all members of the ECAC that hold type certificates for transport 
category airplanes are required to conduct a design review against 
explosion risks.
    The Direction G[eacute]n[eacute]rale de l'Aviation Civile (DGAC), 
which is the airworthiness authority for France, notified us that an 
unsafe condition may exist on certain Airbus Model A300 B4-620, A310-
304, A310-324, and A310-325 airplanes. The DGAC advises that the 
electrical wiring for the fuel quantity indicators (FQIs) of the 
auxiliary center tank (ACT) is installed in harnesses that also contain 
115V wiring that supplies other systems. The DGAC further advises that, 
pursuant to SFAR 88 and JAA reviews, the electrical routing of the ACT 
FQI wiring should be improved by segregating it from the 115V wiring. 
Wiring that is not segregated could result in an ignition source in the 
ACT, which, in combination with flammable fuel vapors, could result in 
a fuel tank explosion and consequent loss of the airplane.

Relevant Service Information

    Airbus has issued the service bulletins in the following table.

                                            Airbus Service Bulletins
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         Service bulletin                Revision                    Date                        Model
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A300-28-6073......................  Original..........  December 23, 2004............  A300 B4-620 airplanes.
A310-28-2149......................  Original..........  September 29, 2004...........  A310-304, A310-324, and
                                                                                        A310-325 airplanes.
----------------------------------------------------------------------------------------------------------------

    These service bulletins describe procedures for installing fused 
adaptors between the external wiring harness and the in-tank wiring at 
the connectors on the fuel tank wall of the ACT. Accomplishing the 
actions specified in the service information is intended to adequately 
address the unsafe condition. The DGAC mandated the service information 
and issued French airworthiness directive F-2005-021, dated February 2, 
2005, to ensure the continued airworthiness of these airplanes in 
France.

FAA's Determination and Requirements of the Proposed AD

    These airplane models are manufactured in France and are type 
certificated for operation in the United States under the provisions of 
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and 
the applicable bilateral airworthiness agreement. Pursuant to this 
bilateral airworthiness agreement, the DGAC has kept the FAA informed 
of the situation described above. We have examined the DGAC's findings, 
evaluated all pertinent information, and determined that we need to 
issue an AD for airplanes of this type design that are certificated for 
operation in the United States.
    Therefore, we are proposing this AD, which would require 
accomplishing the actions specified in the service information 
described previously.

[[Page 45589]]

Difference Between the French Airworthiness Directive and This Proposed 
AD

    The applicability of French airworthiness directive F-2005-021 
excludes airplanes on which Airbus Service Bulletin A300-28-6073 or 
Airbus Service Bulletin A310-28-2149 was accomplished in service. 
However, we have not excluded those airplanes in the applicability of 
this proposed AD; rather, this proposed AD includes a requirement to 
accomplish the actions specified in those service bulletins. This 
requirement would ensure that the actions specified in the service 
bulletins and required by this proposed AD are accomplished on all 
affected airplanes. Operators must continue to operate the airplane in 
the configuration required by this proposed AD unless an alternative 
method of compliance is approved. This difference has been coordinated 
with the DGAC.

Costs of Compliance

    This proposed AD would affect about 2 airplanes of U.S. registry. 
The proposed actions would take about 52 work hours per airplane, at an 
average labor rate of $65 per work hour. Required parts would cost 
about $5,410 per ACT (up to two ACTs per airplane). Based on these 
figures, the estimated cost of the proposed AD for U.S. operators is 
$8,790 per ACT, per airplane.
    Currently, there are no Model A300 B4-620 airplanes of U.S. 
registry with one or more ACTs. However, if an affected airplane is 
imported and placed on the U.S. Register in the future, the required 
actions would take about 52 work hours, at an average labor rate of $65 
per work hour. Required parts would cost about $10,730 per ACT, per 
airplane. Based on these figures, we estimate the cost of this AD to be 
$14,110 per ACT.

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. 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):

Airbus: Docket No. FAA-2005-22032; Directorate Identifier 2005-NM-
049-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by September 
7, 2005.

Affected ADs

    (b) None.
    Applicability: (c) This AD applies to Airbus Model A300 B4-620, 
A310-304, A310-324, and A310-325 airplanes, certificated in any 
category; equipped with one or more auxiliary center tank (ACT), 
except those on which Airbus Modification 12471 has been 
accomplished in production.

Unsafe Condition

    (d) This AD is prompted by the results of fuel system reviews 
conducted by the manufacturer. We are issuing this AD to prevent an 
ignition source in the ACT, which, in combination with flammable 
fuel vapors, could result in 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.

Modification

    (f) Within 24 months after the effective date of this AD: 
Install fused adaptors between the external wiring harness and the 
in-tank wiring at the connectors on the fuel tank wall of the ACT by 
doing all the actions specified in the Accomplishment Instructions 
of the applicable service bulletin in Table 1 of this AD.

                                       Table 1.--Airbus Service Bulletins
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      Airbus service bulletin            Revision                    Date                        Model
----------------------------------------------------------------------------------------------------------------
A300-28-6073......................  Original..........  December 23, 2004............  A300 B4-620 airplanes.
A310-28-2149......................  Original..........  September 29, 2004...........  A310-304, A310-324, and
                                                                                        A310-325 airplanes.
----------------------------------------------------------------------------------------------------------------

Alternative Methods of Compliance (AMOCs)

    (g) The Manager, ANM-116, Transport Airplane Directorate, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.

Related Information

    (h) French airworthiness directive F-2005-021, dated February 2, 
2005, also addresses the subject of this AD.


[[Page 45590]]


    Issued in Renton, Washington, on August 2, 2005.
Kevin Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-15591 Filed 8-5-05; 8:45 am]
BILLING CODE 4910-13-P