AD 99-04-18

This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A300-600 series airplanes, that requires removal of the fuel level sensing amplifier (FLSA) of the trim tank system, modification of the polarization pin code in the electronics bay, and installation of a new, improved FLSA. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent continuous aft transfer of fuel due to the FLSA not supplying electrical power to the trim tank overflow sensor, which could result in potential loss of fuel during flight.

Final rule.

99-04-18 AIRBUS INDUSTRIE: Amendment 39-11043. Docket 98-NM-301-AD.

Applicability: Model A300-600 series airplanes on which Airbus Modification 4801 was accomplished during production and on which Airbus Modification 10778 (reference Airbus Service Bulletin A300-31-6051, dated June 28, 1996) has been accomplished; except those airplanes on which Airbus Modification 11683 (reference Airbus Service Bulletin A300-28-6055, dated January 28, 1997, and Revision 01, dated July 24, 1998) has been accomplished; 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 withparagraph (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 continuous aft transfer of fuel due to the fuel level sensing amplifier (FLSA) not supplying electrical power to the trim tank overflow sensor, which could result in potential loss of fuel during flight, accomplish the following:

(a) Except as provided by paragraph (b) of this AD, within 2 months after the effective date of this AD, remove the FLSA of the trim tank system, modify the polarization pin code in the electronics bay, and install a new, improved FLSA, in accordance with Airbus Service Bulletin A300-28-6055, Revision 01, dated July 24, 1998.

NOTE 2: Accomplishment of the actions specified in paragraph (a) of this AD, prior to the effective date of this AD, in accordance with Airbus Service Bulletin A300-28-6055 dated January 28, 1997, is considered acceptable for compliance with the applicable actions specified in this AD.

(b) For airplanes on which Airbus Service Bulletin A300-31-6051, dated June 28, 1996, is accomplished after the effective date of this AD: Concurrent with the accomplishment of Airbus Service Bulletin A300-31-6051, accomplish the actions required by paragraph (a) of this AD, in accordance with Airbus Service Bulletin A300-28-6055, Revision 01, dated July 24, 1998.

(c) As of the effective date of this AD, no person shall install a FLSA having part number 722-295-2, on any airplane.

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

(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 Airbus Service Bulletin A300-28-6055, Revision 01, dated July 24, 1998. 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 4: The subject of this AD is addressed in French airworthiness directive 98-249-252(B), dated July 1, 1998.

(g) This amendment becomes effective on March 26, 1999.

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 A300-600 series airplanes was published in the Federal Register on December 18, 1998 (63 FR 70068). That action proposed to require removal of the fuel level sensing amplifier (FLSA) of the trim tank system, modification of the polarization pin code in the electronics bay, and installation of a new, improved FLSA.

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

The commenter indicates that it has completed the subject modifications in accordance with French airworthiness directive 98-249-252(B).

Conclusion
After careful review of the available data, including the comment 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 61 airplanes of U.S. registry will be affected by this AD, that it will take approximately 3 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will be supplied 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 $10,980, or $180 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 tothe 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: