AD 98-15-07

This amendment adopts a new airworthiness directive (AD), applicable to certain Dassault Model Mystere-Falcon 50 series airplanes, that requires installation of a reinforcement fitting at the junction of the baggage floor and frame 35 on both the left- and right-hand sides of the airplane. 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 fatigue cracking in the subject area, which could result in reduced structural integrity of the airframe.

Final rule

98-15-07 DASSAULT AVIATION: Amendment 39-10658. Docket 96-NM-230-AD.
Applicability: Model Mystere-Falcon 50 series airplanes, serial numbers 1 through 49 inclusive, 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 prevent fatigue cracking at the junction of the baggage floor and frame 35, which could result in reduced structural integrity of the airframe, accomplish the following:

(a) Install a reinforcement fitting at the junction of the baggage floor and frame 35 on both the left- and right-hand sides of the airplane, in accordance with Avions Marcel Dassault-Breguet Aviation (AMD-BA) Service Bulletin F50-122 (F50-53-2), dated June 25, 1986, at the time specified in paragraph (a)(1) or (a)(2) of this AD, as applicable.

(1) For airplanes on which AMD-BA Service Bulletin F50-163 (F50-00-8) has been incorporated as of the effective date of this AD: Prior to the accumulation of 10,000 total flight cycles or within 6 months after the effective date of this AD, whichever occurs later.

(2) For airplanes on which AMD-BA Service Bulletin F50-163 (F50-00-8) has not been incorporated as of the effective date of this AD: Perform the requirements of paragraph (a)of this AD at the time specified in either paragraph (a)(2)(i) or (a)(2)(ii) of this AD, as applicable.

(i) Except for those airplanes identified in paragraph (a)(2)(ii), prior to the accumulation of 14,000 total flight cycles or within 6 months after the effective date of this AD, whichever occurs later.

(ii) If incorporation of AMD-BA Service Bulletin F50-163 (F50-00-8) is accomplished at or after the accumulation of 10,000 total flight cycles and prior to the accumulation of 14,000 total flight cycles: Perform the requirements of paragraph (a) of this AD concurrently with the incorporation of AMD-BA Service Bulletin F50-163 (F50-00-8).

(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 installation shall be done in accordance with Avions Marcel Dassault-Breguet Aviation (AMD-BA) Service Bulletin F50-122 (F50-53-2), dated June 25, 1986. 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 Dassault Falcon Jet, P.O. Box 2000, South Hackensack, New Jersey 07606. 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 86-74-5(B), dated June 25, 1986.

(e) This amendment becomes effective on August 20, 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 certain Dassault Model Mystere-Falcon 50 series airplanes was published in the Federal Register on August 5, 1997 (62 FR 42077). That action proposed to require installation of a reinforcement fitting at the junction of the baggage floor and frame 35 on both the left- and right-hand sides of the airplane.

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

Request to Revise Cost Impact Information
One commenter requests that the FAA s estimate of the number of airplanes of U.S. registry affected by the proposed AD be revised from 26 to 18 in the cost impact paragraph of the AD. The commenter states that only 18 airplanes of U.S. registry would be affected by the proposed AD because Avions Marcel Dassault-Breguet Aviation (AMD-BA) Service Bulletin F50-122 (F50-53-2), dated June 25, 1986, has already been accomplished for the remaining airplanes. Based on this additional information received since issuance of the proposed AD, the FAA concurs with the commenter s request, and has revised the cost impact information, below, to reflect this information.

One commenter identifies a typographical error in the Explanation of Relevant Service Information section of the proposed AD. The date of AMD-BA Service Bulletin F50-163 (F50-00-8), dated April 10, 1986, was incorrectly specified as April 10, 1996. The FAA acknowledges that an inadvertent typographical error appeared in the proposed AD, and that the correct date of the service bulletin is April 10, 1986. However, since the Explanation of Relevant Service Information section of the preamble to the proposed AD is not restated in the final rule, no change to the final rule is necessary.

Explanation of Changes Made to This Final Rule
In the proposal, the FAA inadvertently omitted the word cycle in references to the number of flight cycles specified for appropriate compliance times for accomplishment of the requirements of this AD. The final rule has been revised throughout paragraph (a) to specify flight cycles for those compliance times.

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 26 Dassault Model Mystere-Falcon 50 series airplanes of U.S. registry will be affected by this AD, that it will take approximately 50 work hours per airplane to accomplish the required installation, and that the average labor rate is $60 per work hour. Required parts will cost approximately $7,000 per airplane. Based on these figures, the cost impact of the installation required by this AD on U.S. operators is estimated to be $260,000, or $10,000 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. However, the FAA has been advised that the installation required by this AD has already been accomplished on 8 airplanes; therefore, only 18 airplanes of U.S. registry are affected. Therefore, the future economic cost impact of the installation required by this AD on U.S. operators is now only $180,000.

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: