AD 98-08-02 ACTIVE

This amendment adopts a new airworthiness directive (AD), applicable to all Airbus Model A300-600 series airplanes, that requires repetitive replacement of the universal joints and steady bearings of the flap transmission system with new parts at regular intervals, or overhaul. This amendment is prompted by a report of a malfunction of a universal joint in the flap transmission system on one wing due to fatigue failure. The actions specified by this AD are intended to ensure replacement or overhaul of certain universal joints and bearings of the transmission system when they have reached their maximum life limit. Failure of universal joints and bearings could lead to an asymmetric condition of the flaps, which could adversely affect controllability of the airplane.

Final rule.

98-08-02 AIRBUS INDUSTRIE: Amendment 39-10451. Docket 95-NM-92-AD.

Applicability: All Model A300-600 series airplanes, certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To ensure replacement or overhaul of certain universal joints and bearings of the flap transmission that have reached their maximum life limit, accomplish the following:

(a) Prior to the accumulation of 16,000 total landings on the universal joints and bearings of the flap transmission system, or within 500 landings after the effective date of this AD, whichever occurs later, accomplish paragraph (a)(1) or (a)(2) of this AD. Thereafter, prior to the accumulation of 16,000 total landings on the universal joints and bearings, repeat the actions required by either paragraph (a)(1) or (a)(2) of this AD.

(1) Replace affected bearings and universal joints of the flap transmission system with new parts, in accordance with Airbus All Operator Telex (AOT) 27-17, Revision 01, dated July 11, 1994, or Airbus Service Bulletin A300-27-6028, dated December 19, 1994; or

(2) Overhaul the affected bearings and universal joints of the flap transmission system in accordance with Airbus Service Bulletin A300-27-6028, dated December 19, 1994. Prior to the accumulation of 16,000 landings after accomplishing the overhaul, replace affected bearing and universal joints with new parts in accordance with the AOT or the service bulletin.

(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

(c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

(d) The actions shall be done in accordance with Airbus All Operator Telex (AOT) 27-17, Revision 01, dated July 11, 1994, or Airbus Service Bulletin A300-27-6028, dated December 19, 1994. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

NOTE 3: The subject of this AD is addressed in French airworthiness directive 94-206-167(B) R1, dated March 15, 1995.

(e) This amendment becomes effective on May 12, 1998.

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 all Airbus Model A300-600 series airplanes was published in the Federal Register on July 18, 1995 (60 FR 36748). That action proposed to require repetitive replacement of the universal joints and steady bearings of the flap transmission system with new parts at regular intervals.

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.

Request to Withdraw the Proposal
Three commenters request that the proposed AD be withdrawn because overhauling is already mandatory under the Maintenance Review Board (MRB) requirements. One commenter states that the maintenance program already includes a certification maintenance requirement (CMR) inspection of these gearboxes and bearings. The commenter states that because CMR inspections are mandatory, the proposed rule is redundant.

The FAA does not concur with the commenters request to withdraw the proposal. The inspections required by this AD are to be accomplished in accordance with the service bulletin, which provides additional detailed information beyond the inspections described in the MRB or in the CMR. Therefore, the FAA has determined that this AD is necessary to address the unsafe condition.

One commenter requests that the proposed AD not be adopted because the AD is based on one incident. The commenter did not provide any additional justification for its request. The FAA does not concur. An assessment by the manufacturer and Direction G n rale de l'Aviation Civile (DGAC) of the incident determined that a similar disconnection of the flap transmission system may occur on other airplanes of the same design. Based on this assessment, the actions requiredby this AD are necessary to address the identified unsafe condition.

Overhaul Versus Replacement
Three commenters request that the proposed AD allow overhaul rather than replacement of the units. One commenter states that the requirements of the proposed AD are not in line with the DGAC and the manufacturer s positions that overhaul of the universal joints and bearings is acceptable. The FAA concurs. However, this overhaul is only acceptable for an additonal 16,000 landings on the affected parts. These overhauled parts provide only a limited service life, at which time the parts must be replaced. The FAA has determined that, in addition to replacement of the units, overhaul, in accordance with Airbus Service Bulletin A300-27-6028, dated December 19, 1994, is also acceptable. Therefore, paragraph (a) of the final rule has been revised accordingly.

Requests to Revise Cost Impact Information
Two commenters request revision of the cost estimate. Two commenters provided additional cost information for overhauling or replacing the bearings. Additionally, the commenters state that the steady bearings are installed in numerous locations in the airplane with two of those steady bearing positions being the subject of the AD.

The FAA concurs with the commenters request to revise the cost estimate based on the new cost for overhaul of the bearings. The commenters state that the cost of accomplishing the overhaul is approximately $4,000 to $4,500 per bearing, rather than $5,660 per airplane, as estimated in the proposed rule. After considering the data presented by the commenters, the FAA concurs that the cost for overhauling the parts may be higher than previously estimated in the proposal. In consideration of this new information, the FAA has revised the cost impact information, below, to indicate that required parts will cost approximately $9,000 per airplane, ($4,500 per bearing, two bearings per airplane). Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $483,000, or $9,660 per airplane.

This AD only requires replacement or overhaul of two bearings. The FAA recognizes that, in accomplishing the requirements of any AD, operators may incur "incidental" costs in addition to "direct" costs. The economic analysis in AD rulemaking actions, however, is limited only to the cost of actions actually required by the AD.

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 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.

Cost Impact
The FAA estimates that 50 Model A300-600 series airplanes of U.S. registry will be affected by this AD, that it will take approximately 11 work hours per airplane to accomplish the required actions, andthat the average labor rate is $60 per work hour. Required parts will cost approximately $9,000 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $483,000, or $9,660 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" 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.
39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive:

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.

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.