Airworthiness Directives; Airbus Model A320-232 and -233 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule.

SUMMARY:

This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A320-232 and -233 series airplanes, that requires replacement of the fuel metering units (FMU) of each engine with modified FMU's. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent an inadvertent increase in thrust, which could result in reduced controllability of the airplane during final approach.

DATES:

Effective July 18, 2000.

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of July 18, 2000.

ADDRESSES:

The service information referenced in this AD may be obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

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

SUPPLEMENTARY INFORMATION:

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Airbus Model A320-232 and -233 series airplanes was published in the Federal Register on March 27, 2000 (65 FR 16157). That action proposed to require replacement of the fuel metering units (FMU) of each engine with new FMU's.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Support for the Proposal

One commenter supports the proposed rule.

Extension of Compliance Threshold

One commenter, an operator, requests that the compliance threshold in the proposed AD be revised to allow the FMU replacements to be completed by December 31, 2001, as recommended in the related Airbus service bulletin. The commenter states that the FMU manufacturer has indicated that its capacity for modification of existing units and manufacture of new units will not be sufficient to meet the 12-month deadline that was specified in the proposed AD.

The FAA concurs with this request. Based on information received since issuance of the proposed AD, the available supply of FMU's will be inadequate to meet the replacement requirements of the AD in the time proposed. In light of this situation, the FAA has determined that extending the compliance time to “18 months after the effective date of this AD” will accommodate the time necessary for affected operators to obtain replacement parts without adversely affecting safety. The FAA considers that this extension will be approximately equivalent to the calendar date suggested by the commenter. The final rule has been revised accordingly.

Reference to FMU Replacement Parts

The same commenter suggests that the proposed AD be revised to refer to replacement of FMU's with “upgraded” or “modified” FMU's. The commenter states that, although the proposed AD requires replacement of the FMU's with “new” FMU's, the existing (old) configuration FMU's also can be modified, reidentified, and reinstalled. The commenter states that rewording the AD will avoid the possible misinterpretation that only new (zero total time) FMU's are acceptable as replacement parts.

The FAA acknowledges that clarification of the requirements is necessary. The FAA's intent in the proposal was to require replacement of the FMU's with FMU's having a different part number, as specified in Airbus Service Bulletin A320-73-1067, dated August 11, 1999. That service bulletin is referenced in the proposed AD as the appropriate source of service information. Although the term “new” could be construed as installing a new unit of the same part number, the FAA notes that replacement with the same part number is not specified in the service bulletin. To avoid confusion, the FAA has revised the final rule to specify that FMU's are to be replaced with “modified” FMU's.

Conclusion

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes described previously. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact

The FAA estimates that 77 series airplanes of U.S. registry will be affected by this AD, that it will take approximately 14 work hours per airplane (7 work hours per engine) to accomplish the required replacements, and that the average labor rate is $60 per work hour. Required parts will be provided by the manufacturer or vendor at no cost to the operators. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $64,680, or $840 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the 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 adopted herein will 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 final rule does not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this action (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption “ADDRESSES.”

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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.