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 A310 and A300-600 series airplanes was published in the Federal Register on October 17, 1994 (59 FR 52273). That action proposed to require modification of flight control computers (FCC's) having part numbers (P/N's) B216ABM6, B350AAM1, B350AAM2, and B350AAM3 (for Model A310 series airplanes); and P/N's B297AAM3, B297AAM4, and B297AAM5 (for Model A300-600 series airplanes).
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.
Two commenters support the proposed rule.
One commenter points out that the Discussion section of the preamble to the notice incorrectly stated that "the flight crew may have attempted a go-around while the airplane was in an out-of-trim condition." The commenter asserts that the subject airplane was correctly trimmed prior to the accident. The FAA acknowledges that the event that prompted the AD could be described more accurately. Therefore, the FAA has revised the Summary section and the statement of unsafe condition in the final rule.
The FAA has recently reviewed the figures it has used over the past several years in calculating the economic impact of AD activity. In order to account for various inflationary costs in the airline industry, the FAA has determined that it is necessary to increase the labor rate used in these calculations from $55 per work hour to $60 per work hour. The economic impact information, below, has been revised to reflect this increase in the specified hourly labor rate.
As a result of recent communications with the Air Transport Association (ATA) of America, the FAA has learned that, in general, some operators may misunderstand the legal effect of AD's on airplanes that are identified in theapplicability provision of the AD, but that have been altered or repaired in the area addressed by the AD. The FAA points out that all airplanes identified in the applicability provision of an AD are legally subject to the AD. If an airplane has been altered or repaired in the affected area in such a way as to affect compliance with the AD, the owner or operator is required to obtain FAA approval for an alternative method of compliance with the AD, in accordance with the paragraph of each AD that provides for such approvals. A note has been included in this rule to clarify this long-standing requirement.
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 previously described. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.
The FAA estimates that 15Model A310 series airplanes and 36 Model A300-600 series airplanes of U.S. registry will be affected by this AD.
Since the manufacturer has not yet developed one specific modification commensurate with the requirements of this AD, the FAA is unable at this time to provide specific information as to the number of work hours or cost of parts that would be required to accomplish the required modification. A further problem in developing a specific cost estimate is the fact that modification costs are expected to vary from operator to operator and from airplane to airplane depending upon airplane configuration. The compliance time of 24 months should provide ample time for the development, approval, and installation of an appropriate modification.
However, based on similar modifications accomplished previously on other FCC's installed on other airplane models, the FAA can reasonably estimate that the required modification may require as few as 2 work hours or as many as 50 work hours to accomplish, at an average labor rate of $60 per work hour. The cost of required parts could range from a negligible amount to as much as $1,500 per airplane. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be between $6,120 ($120 per airplane) and $229,500 ($4,500 per airplane).
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" 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, 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 USC 106(g), 40101, 40113, 44701.
39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: