04-4936. Airworthiness Directives; Airbus Model A300 B2 and A300 B4 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Airbus Model A300 B2 and A300 B4 series airplanes. This proposal would require modification of the 107VU electronics rack in the avionics compartment to ensure that fluid does not enter the rack. This action is necessary to prevent the loss of electrical power during flight, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by April 19, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-337-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2002-NM-337-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

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 [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2002-NM-337-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-337-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Direction Générale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, notified the FAA that an unsafe condition may exist on certain Airbus Model A300 B2 and A300 B4 series airplanes. The DGAC advises that, during final approach of an in-service airplane, the electrical power on a number of circuits was lost. An internal short circuit on contact 12HR, located on the backplate of the 107VU electronics rack, caused the internal parts of the contact to melt down, and damaged the wire harness that supplies power to the number 3 pitot probe heating system. This incident was caused by fluid dripping into the 107VU electronics rack, located below galley G3, due to a degraded cabin floor seal or a blocked drainpipe. This condition, if not corrected, could result in the loss of electrical power during flight, and reduced controllability of the airplane.

Explanation of Relevant Service Information

The FAA has reviewed and approved Airbus Service Bulletin A300-24-0098, dated June 13, 2002, which describes procedures for modifying the 107VU electronics rack. The modification includes adding deflectors above the cover and ventilation grids on the electronics rack; making a drip loop with the power supply bundles at the input of the rack; adding sealant in the cable thru-fittings; and adding protection on the pitot heating system wiring. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

The DGAC classified this service bulletin as mandatory and issued French airworthiness directive 2002-579(B) R1, dated February 19, 2003, to ensure the continued airworthiness of these airplanes in France.

Explanation of Requirements of Proposed AD

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously.

Cost Impact

The FAA estimates that 120 airplanes of U.S. registry would be affected by this proposed AD. It would take approximately 4 work hours per airplane to accomplish the proposed actions, at an average labor rate of $65 per work hour. Required parts would cost approximately $390. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $78,000, or $650 per airplane, per inspection cycle.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this 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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Airbus: Docket 2002-NM-337-AD.

Applicability: Model A300 B2 and A300 B4 series airplanes, except those on which Airbus Modification 12447 has been accomplished; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent fluid from entering the 107VU electronics rack, which could result in the loss of electrical power during flight, and consequent reduced controllability of the airplane, accomplish the following:

Modification

(a) Within 12 months after the effective date of this AD, modify the 107VU electronics rack in accordance with the Accomplishment Instructions of Airbus Service Bulletin A300-24-0098, dated June 13, 2002.

Alternative Methods of Compliance

(b) In accordance with 14 CFR 39.19, the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, is authorized to approve alternative methods of compliance for this AD.

Note 1:

The subject of this AD is addressed in French airworthiness directive 2002-579(B) R1, dated February 19, 2003.

Issued in Renton, Washington, on February 24, 2004.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.