[Federal Register Volume 71, Number 126 (Friday, June 30, 2006)]
[Proposed Rules]
[Pages 37512-37515]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 06-5872]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25221; Directorate Identifier 2006-NM-122-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A300 and A310 Airplanes; 
and Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, 
and Model C4-605R Variant F Airplanes (Collectively Called A300-600 
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 all Airbus Model A300 and A310 airplanes and A300-600 series 
airplanes. This proposed AD would require inspecting for discrepancies 
of all electrical bundles located in the leading and trailing edges of 
the wings, and performing corrective actions if necessary. This 
proposed AD results from fuel system reviews conducted by the 
manufacturer. We are proposing this AD to prevent an ignition source, 
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 July 31, 2006.

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: Tom Stafford, Aerospace Engineer,

[[Page 37513]]

International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
227-1622; fax (425) 227-1149.

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-2006-
25221; Directorate Identifier 2006-NM-122-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 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 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.
    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.
    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.
    The European Aviation Safety Agency (EASA) notified us that an 
unsafe condition may exist on all Airbus Model A300 and A310 airplanes; 
and Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, 
and Model C4-605R Variant F airplanes (collectively called A300-600 
series airplanes). The EASA advises us of the potential for 
discrepancies, including but not limited to chafing, of all electrical 
bundles in the leading and trailing edges of the wings of these 
airplanes. This condition, if not corrected, could result in an 
ignition source, 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 listed in the table below.

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                                             Airbus service bulletin,
              Airplane model                   including appendix 01                       Date
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A300.....................................  A300-24-0102................  December 15, 2005.
A310.....................................  A310-24-2095................  December 15, 2005.
A300-600 series..........................  A300-24-6092................  December 15, 2005.
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    These service bulletins describe procedures for performing detailed 
inspections for discrepancies of all electrical bundles located in the 
leading and trailing edges of the wings, and corrective actions if 
necessary. The inspections include inspecting for the following:
     Inadequate clearance between electrical wire harnesses and 
adjacent components or structure, including support structure, 
stringers, fasteners, pipes, bonding leads, or any metallic component 
which could create a conductive path to structure.
     Evidence of chafing of electrical cable harnesses.
     Discrepancies of clamps (including, but not limited to, 
unacceptable condition, unacceptable condition of

[[Page 37514]]

cushioning and anti-chafing devices, or evidence of chafing against 
electrical cable harnesses).
     Discrepancies of cable ties (including, but not limited 
to, unacceptable condition, or evidence of chafing against electrical 
cable harnesses).
     Discrepancies of convoluted conduits (including, but not 
limited to, unacceptable condition, evidence of chafing against 
electrical cable harnesses, and absence of drainage holes in the 
conduits).
     Discrepancies of metallic conduits (including, but not 
limited to, unacceptable condition, evidence of chafing against 
electrical cable harnesses, and absence of or unacceptable condition of 
drainage holes in the conduits).
    Corrective actions include repairing any chafed electrical cable 
harnesses, replacing discrepant clamps with new clamps, repairing or 
replacing discrepant cable ties, installing drainage holes in 
convoluted or metallic conduits, and repairing any discrepant 
convoluted or metallic conduits. If clearance is not adequate between 
electrical wire harnesses and adjacent components or structure, the 
service bulletins specify contacting Airbus for corrective action. The 
service bulletins also specify to report all findings to Airbus.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition. The EASA mandated 
the service information and issued airworthiness directive 2006-0076, 
dated April 3, 2006, to ensure the continued airworthiness of these 
airplanes in the European Union.

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. As described in FAA 
Order 8100.14A, ``Interim Procedures for Working with the European 
Community on Airworthiness Certification and Continued Airworthiness,'' 
dated August 12, 2005, the EASA has kept the FAA informed of the 
situation described above. We have examined the EASA's findings, 
evaluated all pertinent information, and determined that we need to 
issue an AD for products 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, except as discussed under ``Differences Between 
the Proposed AD and Service Information.'' The proposed AD would also 
require sending the inspection results to Airbus.

Differences Between the Proposed AD and Service Information

    The service bulletins specify to contact the manufacturer for 
instructions on how to correct inadequate clearance between electrical 
wire harnesses and adjacent components or structure and repair certain 
conditions, but this proposed AD would require correcting that 
condition using a method that we or the EASA (or its delegated agent) 
approve. In light of the type of corrective action that would be 
required to address the unsafe condition, and consistent with existing 
bilateral airworthiness agreements, we have determined that, for this 
proposed AD, a corrective action that we or the EASA approve would be 
acceptable for compliance with this proposed AD.

Clarification of Inspection Terminology

    In this proposed AD, the ``detailed visual inspection'' specified 
in the EASA's AD and the Airbus service bulletins is referred to as a 
``detailed inspection.'' We have included the definition for a detailed 
inspection in a note in the proposed AD.

Costs of Compliance

    This proposed AD would affect about 227 airplanes of U.S. registry. 
The proposed actions would take about 10 work hours per airplane, at an 
average labor rate of $80 per work hour. Based on these figures, the 
estimated cost of the proposed AD for U.S. operators is $181,600, or 
$800 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.

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-2006-25221; Directorate Identifier 2006-NM-
122-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by July 31, 
2006.

Affected ADs

    (b) None.

[[Page 37515]]

Applicability

    (c) This AD applies to all Airbus Model A300 and A310 airplanes; 
and all Airbus Model A300 B4-601, B4-603, B4-620, B4-622, B4-605R, 
B4-622R, F4-605R, and F4-622R airplanes, and A300 C4-605R Variant F 
airplanes; certificated in any category.

Unsafe Condition

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

Service Bulletin Reference

    (f) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of the following service bulletins, as 
applicable:
    (1) For Model A300 airplanes: Airbus Service Bulletin A300-24-
0102, including Appendix 01, dated December 15, 2005;
    (2) For Model A310 airplanes: Airbus Service Bulletin A310-24-
2095, including Appendix 01, dated December 15, 2005; and
    (3) For Model A300 B4-601, B4-603, B4-620, B4-622, B4-605R, B4-
622R, F4-605R, and F4-622R airplanes, and A300 C4-605R Variant F 
airplanes: Airbus Service Bulletin A300-24-6092, including Appendix 
01, dated December 15, 2005.

Inspections and Corrective Actions

    (g) Within 44 months after the effective date of this AD, 
perform detailed inspections for discrepancies of all electrical 
bundles located in the leading and trailing edges of the wings, and 
all applicable corrective actions, by doing all of the actions in 
the service bulletin, except as provided by paragraph (h) of this 
AD. All corrective actions must be done before further flight.


    Note 1: For the purposes of this AD, a detailed inspection is: 
``An intensive examination of a specific item, installation, or 
assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good 
lighting at an intensity deemed appropriate. Inspection aids such as 
mirror, magnifying lenses, etc., may be necessary. Surface cleaning 
and elaborate procedures may be required.''

Exception to Corrective Action Instructions

    (h) If inadequate clearance is found between any electrical wire 
harness and adjacent components or structure: Before further flight, 
correct the inadequate clearance using a method approved by either 
the Manager, International Branch, ANM-116, Transport Airplane 
Directorate, FAA; or the European Aviation Safety Agency (EASA) (or 
its delegated agent).

Reporting

    (i) Within 30 days after doing the inspections required by this 
AD, or within 30 days after the effective date of the AD, whichever 
is later: Submit a report of the findings (both positive and 
negative) of the inspections required by paragraph (g) of this AD to 
Airbus Engineering, c/o SE-E54, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. The report must include the airplane serial 
number or registration number, the number of flight cycles and 
flight hours on the airplane, the date of the inspection, the 
location of the defect, the conditions found, and the type of 
repair. Submitting Appendix 01 of the service bulletin to Airbus is 
acceptable for compliance with this requirement. Under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), 
the Office of Management and Budget (OMB) has approved the 
information collection requirements contained in this AD and has 
assigned OMB Control Number 2120-0056.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, International Branch, 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.
    (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.

Related Information

    (k) EASA's airworthiness directive 2006-0076, dated April 3, 
2006, also addresses the subject of this AD.

    Issued in Renton, Washington, on June 22, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 06-5872 Filed 6-29-06; 8:45 am]
BILLING CODE 4910-13-P