Airworthiness Directives; Airbus Model A300 and A300-600 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 all Airbus Model A300 and A300-600 series airplanes. This proposal would require verifying the correct location of the labels of the hydraulic pipes supplying the strut unlocking actuator of the left-hand main landing gear (MLG), and of the pipes of the left- and right-hand cross brace; reidentifying the pipes; and replacing any incorrectly located label with a new label. This action is necessary to prevent cross connection of the hydraulic hoses or pipes that supply the main strut unlocking actuator, and collapse of the MLG under lateral taxiing loads. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by October 10, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-154-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 (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2000-NM-154-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 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Airbus Industrie, 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:

Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

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 notice 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 notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NM-154-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. 2000-NM-154-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Direction Generale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, notified the FAA that an unsafe condition may exist on all Airbus Model A300 and A300-600 series airplanes. The DGAC advises that an operator reported the collapse of the left-hand main landing gear (MLG) during taxiing. Such collapse of the MLG resulted in severe damage to the airplane and the engine.

Investigation of the incident indicated that the collapse of the MLG was caused by cross connection of the hydraulic hoses that supply the strut unlocking actuator of the left-hand MLG. In addition, the labeling of the “up” and “down” hydraulic pipes, which are attached to the MLG and connected to the hoses, was inverted. The cross connection of the hoses, in combination with the inverted labeling, caused the MLG to become unlocked, which led to its collapse under lateral taxiing loads. Additional investigations revealed that several other airplanes in the fleet had been delivered with similar inverted labeling of the hydraulic pipes of the left-hand MLG. (This installation on the right-hand MLG was labeled correctly.)

Cross connection of the hydraulic hoses or pipes that supply the main strut unlocking actuator, if not corrected, could lead to collapse of the MLG under lateral taxiing loads.

Explanation of Relevant Service Information

Airbus has issued Service Bulletins A300-32A0437 (for Model A300 series airplanes) and A300-32A6080 (for Model A300-600 series airplanes), both dated April 5, 2000. These service bulletins describe procedures for verifying the correct location of the labels of the hydraulic pipes supplying the strut unlocking actuator of the left-hand main landing gear (MLG), and of the pipes of the left-and right-hand cross brace; reidentifying the pipes; and replacing any incorrectly located label with a new label. The service bulletins reference Airbus Service Bulletins A300-57A0234 and A300-57A6087, as well as Messier-Dowty International Service Bulletin No. 470-32-792, as additional sources of service information for accomplishment of the specified actions.

Accomplishment of the actions specified in Airbus Service Bulletins A300-32A0437 and A300-32A6080 is intended to adequately address the identified unsafe condition. The DGAC classified these service bulletins as mandatory and issued French airworthiness directive 2000-204-309(B), dated May 17, 2000, in order to assure the continued airworthiness of these airplanes in France.

FAA's Conclusions

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. The FAA has examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously. The actions would be required to be accomplished in accordance with the service bulletins described previously.

Cost Impact

The FAA estimates that 87 Model A300 and A300-600 series airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 1 work hour per airplane to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Required parts would be provided by the vendor at no cost to operators. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $5,220, or $60 per airplane.

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 AD were not adopted.

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.