The FAA proposed to amend 14 CFR part 39 with an AD for certain Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model A300 C4-605R Variant F airplanes (collectively called A300-600 series airplanes). That action, published in the Federal Register on April 6, 2005 (70 FR 17340), proposed to require an inspection for evidence of chafing between the hydraulic flexible hose and the ram air turbine (RAT) hub, and related investigative and corrective actions if necessary.
Comments
We provided the public the opportunity to participate in the development of this AD. We have considered the comment that was submitted on the proposed AD.
Request To Revise Compliance Time
The commenter requests that the compliance time be revised from the proposed 2,500 flight hours after the effective date of the AD to 15 months after the effective date of the AD. However, the commenter acknowledges that the 2,500-flight-hour compliance time shouldbe sufficient for the 12 U.S.-registered airplanes to receive the required inspection. The commenter notes that revising the compliance time would allow the proposed inspection to be accomplished during a regularly scheduled C-check. The commenter notes that it has no affected airplanes in its fleet. The commenter also states that, based on its experience, replacing the RAT would take about 3 hours.
We do not concur with the commenter's request to revise the compliance time. In developing an appropriate compliance time for this AD, we considered the manufacturer's recommendation; the recommendation of the Direction Generale de l'Aviation Civile, which is the airworthiness authority for France; the degree of urgency associated with the subject unsafe condition; the average utilization of the affected fleet; the maintenance schedules of the majority of affected operators; and the time necessary to perform the inspection (1 work hour). In light of all of these factors, we find thata 2,500- flight-hour compliance time represents an appropriate interval of time for affected airplanes to continue to operate without compromising safety. We have determined that this compliance time will also allow the majority of affected operators to comply with the requirements of this AD at a scheduled maintenance visit. We have not changed the AD in this regard.
We acknowledge the commenter's estimate that replacing the RAT would take about 3 hours. However, the economic analysis of an AD is limited to the cost of actions that are actually required. The economic analysis does not consider the costs of conditional actions, such as replacing the RAT if damage found during the required inspection exceeds the limits specified in the Airbus A300-600 Component Maintenance Manual. Such conditional corrective action would be required--regardless of AD direction--to correct an unsafe condition identified in an airplane and to ensure that the airplane is operated in an airworthy condition, as required by the Federal Aviation Regulations. We have not changed the AD in this regard.
Explanation of Change to Applicability
We have revised the applicability of this AD to identify model designations as published in the most recent type certificate data sheet for the affected models.
Explanation of Additional Change to Final Rule
We have revised paragraph (f) of this AD to correct a typographical error. (In one place, the proposed AD contained the term "RAMs" instead of "RATs.")
Conclusion
We have carefully reviewed the available data, including the comment that was submitted, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
The following table provides the estimated costs for U.S. operators to comply with this AD.
Estimated Costs
Action
Work hours
Average labor rate per hour
Parts
Cost per airplane
Number of U.S.-
registered airplanes
Fleet cost
Inspection
1
$65
None required
$65
12
$780
Rework binding
1
65
None required
65
12
780
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements." Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.
Regulatory Findings
We have determined that this AD will not have federalism implications under Executive Order 13132. This AD 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.
For the reasons discussed above, I certify that this AD:
(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.
We prepared a regulatory evaluation of the estimated costs to comply with this AD. See the ADDRESSES section for a location to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):