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Proposed Rule

Airworthiness Directives; Airbus Model A318, A319, A320, and A321 Airplanes

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

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AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Airbus Model A318-100, A319-100, A320-200, A321-100, and A321-200 series airplanes; and Model A320-111 airplanes. The existing AD currently requires modification of the electrical bonding of all structures and systems installed inside the center fuel tank. That AD results from fuel system reviews conducted by the manufacturer. This proposed AD would require modification of additional bonding points inside the center fuel tank. This proposed AD results from a report that additional bonding points need to be modified in order to prevent electrical arcing in the center fuel tank. We are proposing this AD to prevent electrical arcing in the center fuel tank due to inadequate bonding, which could result in an explosion of the center fuel tank and consequent loss of the airplane.

DATES:

We must receive comments on this proposed AD by February 12, 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 9:00 a.m. and 5:00 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.

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FOR FURTHER INFORMATION CONTACT:

Tim Dulin, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone (425) 227-2141; fax (425) 227-1149.

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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 “Docket No. FAA-2007-26812; Directorate Identifier 2006-NM-199-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. Start Printed Page 1468

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.

On September 9, 2005, we issued AD 2005-19-14, amendment 39-14279 (70 FR 55228, September 21, 2005), for certain Airbus Model A318-100, A319-100, A320-200, A321-100, and A321-200 series airplanes; and Model A320-111 airplanes. That AD requires modification of the electrical bonding of all structures and systems installed inside the center fuel tank. We issued that AD to prevent electrical arcing in the center fuel tank due to inadequate bonding, which could result in an explosion of the center fuel tank and consequent loss of the airplane.

Actions Since Existing AD Was Issued

Since we issued AD 2005-19-14, the European Aviation Safety Agency (EASA), which is the aviation authority for the European Union, informed us that certain bonding points that should be modified were not included in the Accomplishment Instructions of Airbus Service Bulletin A320-28-1104, dated December 2, 2003; Revision 01, dated December 8, 2004; and Revision 02, dated February 21, 2005. Airbus Service Bulletin A320-28-1104, Revision 01, was referenced as the appropriate source of service information for modifying the electrical bonding, as required by AD 2005-19-14.

Relevant Service Information

Airbus has issued Service Bulletin A320-28-1104, Revision 03, including Appendix 01, dated February 23, 2006. The procedures in Revision 03 are essentially the same as those specified in earlier revisions, except that Revision 03 includes additional bonding points that were not included in the original issue, Revision 01, or Revision 02 of the service bulletin. Accomplishing the actions specified in Revision 03 of the service bulletin is intended to adequately address the unsafe condition. EASA mandated the service information and issued EASA airworthiness directive 2006-0176, dated June 26, 2006, to ensure the continued airworthiness of these airplanes in the European Union. EASA airworthiness directive 2006-0176 supersedes French airworthiness directive F-2005-028, dated February 16, 2005, which was referenced in AD 2005-19-14 as the parallel French airworthiness directive.

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 airplanes of this type design that are certificated for operation in the United States.

This proposed AD would supersede AD 2005-19-14 and would retain the requirements of the existing AD. This proposed AD would also add the requirement to modify additional bonding points.

Clarification of Alternative Method of Compliance (AMOC) Paragraph

We have revised this action to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies. Start Printed Page 1469

Explanation of Change in Applicability

We have changed the airplane model designations in the applicability of this proposed AD to be consistent with the parallel EASA airworthiness directive.

Costs of Compliance

The following table provides the estimated costs for U.S. operators to comply with this proposed AD. There are approximately 720 U.S.-registered airplanes. The average labor rate is $80 per hour.

Estimated Costs

ActionWork hoursPartsCost per airplaneFleet cost
Modification of electrical bonding (required by AD 2005-19-14)49 to 64$10 to $370$3,930 to $5,490$2,829,600 to $3,952,800
Modification of additional bonding points (new proposed action)6 to 7$100$580 to $660$417,600 to $475,200

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.

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List of Subjects in 14 CFR Part 39

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The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

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PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

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Authority: 49 U.S.C. 106(g), 40113, 44701.

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[Amended]

2. The Federal Aviation Administration (FAA) amends § 39.13 by removing amendment 39-14279 (70 FR 55228, September 21, 2005) and adding the following new airworthiness directive (AD):

Airbus: Docket No. FAA-2007-26812; Directorate Identifier 2006-NM-199-AD.

Comments Due Date

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

Affected ADs

(b) This AD supersedes AD 2005-19-14.

Applicability

(c) This AD applies to Airbus Model A318, A319, A320, and A321 airplanes; certificated in any category; except airplanes that have received Airbus Modification 31892 in production.

Unsafe Condition

(d) This AD results from a report that additional bonding points need to be modified in order to prevent electrical arcing in the center fuel tank. We are issuing this AD to prevent electrical arcing in the center fuel tank due to inadequate bonding, which could result in an explosion of the center fuel tank 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.

Restatement of The Requirements of AD 2005-19-14:

Modification

(f) Within 58 months after October 26, 2005 (the effective date of AD 2005-19-14): Modify the electrical bonding of all structures and systems installed inside the center fuel tank by accomplishing all of the actions in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320-28-1104, Revision 01, dated December 8, 2004; or Revision 02, dated February 21, 2005; or Revision 03, including Appendix 01, dated February 23, 2006. After the effective date of this AD, only Revision 03 may be used.

Actions Accomplished According to Previous Issue of Service Bulletin

(g) Actions done before October 26, 2005, in accordance with Airbus Service Bulletin A320-28-1104, dated December 2, 2003, are acceptable for compliance with the corresponding requirements of paragraph (f) of this AD.

New Requirements Of This AD:

Modification (Additional Bonding Points)

(h) For airplanes on which the actions specified in Airbus Service Bulletin A320-28-1104, dated December 2, 2003; Revision 01, dated December 8, 2004; or Revision 02, dated February 21, 2005; have been done before the effective date of this AD: Within 78 months after the effective date of this AD, modify the electrical bonding of the structures and systems identified in the additional actions specified in paragraph 3.B.(3) of the Accomplishment Instructions of Airbus Service Bulletin A320-28-1104, Revision 03, including Appendix 01, dated February 23, 2006.

Alternative Methods of Compliance (AMOCs)

(i)(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. Start Printed Page 1470

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

(3) AMOCs approved previously in accordance with AD 2005-19-14, are approved as AMOCs for the corresponding provisions of paragraph (f) of this AD.

Related Information

(j) European Aviation Safety Agency (EASA) airworthiness directive 2006-0176, dated June 26, 2006, also addresses the subject of this AD.

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Issued in Renton, Washington, on December 26, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.

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[FR Doc. E7-315 Filed 1-11-07; 8:45 am]

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