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 Industrie Model A320 series airplanes was published in the Federal Register on June 28, 1999 (64 FR 34588). That action proposed to require replacement of the disc valve and spring in the low pressure non-return valve of the airborne ground check module (AGCM) of the ram air turbine (RAT).
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
Three commenters support the proposed rule.
Request to Revise Cost Impact Information
One commenter states that the FAA has underestimated the cost impact of the proposed AD. The commenter indicates that the proposed service bulletins will require a total of 4.25 work hours per airplane to accomplish, and requests that the cost estimate of the proposed rule be revised to reflect that work-hour total.
The FAA does not concur with the request to revise the cost impact information of this final rule, which describes only the "direct" costs of the specific actions required by this AD. The number of work hours necessary to accomplish the required actions (1 work hour) was provided to the FAA by the manufacturer based on the best data available to date. This number represents the time necessary to perform only the actions actually required by this AD. The FAA recognizes that, in accomplishing the requirements of any AD, operators may incur "incidental" costs in addition to the "direct" costs. The cost analysis in AD rulemaking actions, however, typically does not include incidental costs, such as the time required to gain access and close up; planning time; or time necessitated by other administrative actions. Because incidental costs may vary significantly from operator to operator, they are almost impossible to calculate.
Request for Revision of Applicability
One commenter does not agree that the proposed AD should be applicable to its fleet since its airplanes were equipped with Airbus Modification 27189 at production, which allows installation of a new Sundstrand RAT, and deletes the requirement for an airborne ground check module (AGCM). The commenter adds that Airbus Service Bulletin A320-29-1086 (which was cited as the appropriate source of service information for accomplishment of the actions in the proposed AD) erroneously lists its airplanes as being affected.
The FAA concurs with the request to revise the applicability of the final rule. The discrepancy involving those misidentified airplanes has been clarified with Airbus Industrie as a typographical error and will be corrected in the next revision to the service bulletin. The FAA notes that the applicability of the proposed rule does not specifically reference airplanes listed in the effectivity of the service bulletin. However, the applicability of the final rule has been revised to exclude those airplanes on which Airbus Modification 27189 was installed in production.
Request to Allow Later Revisions of Service Bulletins
This same commenter requests that later revision levels of Airbus Service Bulletin A320-29-1086 be reflected in the applicability of the proposed AD. As support, the commenter indicates that, if its airplanes are removed from the effectivity in subsequent revisions of the service bulletin, those airplanes would not be included in the applicability of the proposed AD.
Although the FAA agrees that the service bulletin revision proposed by Airbus would in effect remove those certain airplanes from the applicability of the final rule, the FAA does not concur with the request to revise the AD to reflect later service bulletin revisions. Where a specific service bulletin is referenced in an AD, the use of the phrase, "or later FAA-appproved revisions," violatesOffice of the Federal Register regulations regarding approval of materials that are incorporated by reference. However, as stated previously, the FAA has revised the applicability of the final rule to exclude airplanes on which Airbus Modification 27189 has been accomplished; therefore, further revision of the applicability will not be necessary.
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 change described previously. The FAA has determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD.
Cost Impact
The FAA estimates that 165 Model A320 series airplanes of U.S. registry will be affected by this AD, that it will take approximately 1 work hour per airplane to accomplish the required replacement, and that the average labor rate is $60 per work hour. Required parts willbe provided by the manufacturer at no cost to the operators. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $9,900, or $60 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 substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" underExecutive 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.
39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: