AD 97-20-08

This amendment adopts a new airworthiness directive (AD), applicable to all Airbus Model A300, A300-600, and A310 series airplanes, that requires inspecting the bearings located in the mechanical control linkage of the nose landing gear (NLG) free-fall mechanism for discrepancies, replacing any discrepant bearings with stainless steel bearings, and conducting a test to ensure that the NLG free-fall mechanism extends properly. This amendment is prompted by a report indicating that, during an operational test of the NLG, the landing gear failed to extend. The actions specified by this AD are intended to prevent the bearings from seizing, which could lead to the loss of NLG free-fall extension capability.

Final rule.

97-20-08 AIRBUS INDUSTRIE: Amendment 39-10146. Docket 96-NM-215-AD.

Applicability: All Model A300, A300-600, and A310 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 otherwise 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 (d) 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 prevent the bearings in the mechanical control linkage of the nose landing gear (NLG) free-fall mechanism from seizing, which could lead to the loss of NLG free-fall extension capability, accomplish the following:

(a) Within 30 days after the effective date of this AD, conduct an inspection to determine whether carbon steel or stainless steel bearings are installed in the mechanical control linkage of the NLG free-fall mechanism, in accordance with Airbus Service Bulletin A300-32- 0418 (for Model A300 series airplanes), A300-32-6061 (for Model A300-600 series airplanes), or A310-32-2098 (for Model A310 series airplanes), all Revision 1, all dated April 29, 1996.

(b) If stainless steel bearings are installed, prior to further flight, conduct a test to ensure that the NLG free-fall mechanism extends properly, in accordance with Airbus Service Bulletin A300-32-0418 (for Model A300 series airplanes), A300-32-6061 (for Model A300-600 series airplanes), or A310-32-2098 (for Model A310 series airplanes), all Revision 1, all dated April 29, 1996.

(c) If carbon steel bearings are installed, prior to further flight, replace them with stainless steel bearings, and conduct a test to ensure that the NLG free-fall mechanism extends properly, in accordance with Airbus Service Bulletin A300-32-0418 (for Model A300 series airplanes), A300-32-6061 (for Model A300-600 series airplanes), or A310-32-2098 (for Model A310 series airplanes), all Revision 1, all dated April 29, 1996.

(d) 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, Standardization Branch, ANM-113, 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, Standardization Branch, ANM-113.

NOTE 2: Information concerning the existence of approved alternative methodsof compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(e) 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.

(f) The actions shall be done in accordance with the following Airbus service bulletins, which contain the specified effective pages:

Service Bulletin
Referenced and Date

Page Number
Revision Level
Shown on Page
Date
Shown on Page
A300-32-0418,
Revision 1,
April 29, 1996
1-6, 10-13

7-9, 14-23
1

Original
April 29, 1996

October 5, 1995
A310-31-2098,
Revision 1,
April 29, 1996
1-6, 8, 9,
11-14
7, 10, 15-25
1

Original
April 29, 1996

October 5, 1995
A300-32-6061,
Revision 1,
April 29, 1996
1-5, 8, 9, 11-14

6, 7, 10, 15-25
1

Original
April 29, 1996

October 5, 1995

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.

(g) This amendment becomes effective on November 4, 1997.

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, A300-600, and A310 series airplanes was published in the Federal Register on April 1, 1997 (62 FR 15441). That action proposed to require inspecting the bearings located in the mechanical control linkage of the nose landing gear (NLG) free-fall mechanism for discrepancies, replacing any discrepant bearings with stainless steel bearings, and conducting a test to ensure that the NLG free-fall mechanism extends properly.

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

Both commenters support the proposed rule.

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 as proposed.

Cost Impact
The FAA estimates that 127 Model A300, A300-600, and A310 airplanes of U.S. registry will be affected by this AD, that it will take approximately 14 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will cost approximately $552 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $176,784, or $1,392 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 ofgovernment. 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: