AD 94-21-04

This amendment adopts a new airworthiness directive (AD), applicable to certain Model ATR42-200 and -300 series airplanes, that requires a one-time dye penetrant inspection to detect cracking in certain hinge pins of the nose landing gear (NLG), and replacement of cracked pins with crack-free pins. This amendment is prompted by reports of cracking of certain hinge pins in the NLG. The actions specified by this AD are intended to prevent collapse of the NLG due to cracking of the hinge pins.

Final rule.

94-21-04 AEROSPATIALE: Amendment 39-9046. Docket 94-NM-43-AD.

Applicability: Model ATR42-200 and -300 series airplanes equipped with hinge pins installed at the nose landing gear (NLG) that are manufactured by Nardi, have part number D56867, and have serial numbers beginning with the letter "N", certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent collapse of the NLG due to cracking of the hinge pins, accomplish the following:

(a) Prior to the accumulation of 10,000 total landings or within 1,000 landings after the effective date of this AD, whichever occurs later, perform a dye penetrant inspection to detect cracking in the hinge pins on the NLG in accordance with Avions de Transport Regional Service Bulletin ATR42-32-0064, dated January 17, 1994.

(1) If no cracking is found, prior to further flight, reinstall that hinge pin in accordance with the service bulletin.

(2) If cracking is found, prior to further flight, install a new hinge pin or a pin that has been previously inspected and found to be crack-free, in accordance with the service bulletin.

(b) As of the effective date of this AD, no hinge pin manufactured by Nardi having part number D56867 and any serial number beginning with the letter "N," shall be installed on the NLG of any airplane, unless that pin has been previously inspected and has been found to be crack-free, in accordance with Avions de Transport Regional Service Bulletin ATR42-32-0064, dated January 17, 1994.

(c) 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: Informationconcerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Manager, Standardization Branch, ANM-113.

(d) 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.

(e) The inspection, reinstallation, and installation shall be done in accordance with Avions de Transport Regional Service Bulletin ATR42-32-0064, dated January 17, 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 Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, 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.

(f) This amendment becomes effective on November 28, 1994.

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 Aerospatiale Model ATR42-200 and -300 series airplanes was published in the Federal Register on June 6, 1994 (59 FR 29210). That action proposed to require a one-time dye penetrant inspection to detect cracking in certain hinge pins in the NLG, and replacement of cracked pins with crack-free pins.

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 supports the proposed rule.

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.

The FAA estimates that 128 airplanes of U.S. registry will be affected by this AD, that it will take approximately 6 work hours per airplane to accomplish the required actions, and that the average labor rate is $55 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $42,240, or $330 per airplane.

The total 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.

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 thisaction (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 toread as follows:
Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.
39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: