AD 95-21-18

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model ATP airplanes, that requires an inspection to ensure that various components of the retraction actuator of the nose landing gear (NLG) are secure, and an inspection of the bearing cap mounting holes for correct hole and thread length. This AD also requires a later inspection for certain discrepancies of the retraction actuator; installation of revised tolerance bushings; and correction of any discrepancy found. This amendment is prompted by reports of failure of the attachment bolts of the bearing cap of the retraction actuator of the NLG. The actions specified by this AD are intended to prevent the inability to raise or lower the NLG, or possible collapse of the NLG, due to failure of the attachment bolts of the bearing cap.

Final rule

95-21-18 JETSTREAM AIRCRAFT LIMITED (Formerly, British Aerospace Commercial Aircraft Limited): Amendment 39-9405. Docket 94-NM-242-AD.
Applicability: Model ATP airplanes, constructor's numbers 2002 through 2056 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 use the authority provided in paragraph (c) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To prevent the inability to raise or lower the nose landing gear (NLG), or a possible collapse of the NLG, accomplish the following:

(a) Within 300 hours time-in-service or 90 days after the effective date of this AD, whichever occurs first: Perform an inspection to ensure that the components of the bracket attachment assembly of the retraction actuator of the NLG are secure, and to ensure that the inboard and outboard support brackets of the mounting holes of the bearing cap have correct hole and thread lengths, in accordance with paragraph 2.A. of the Accomplishment Instructions of Jetstream Service Bulletin ATP-53-30-10372A, dated November 3, 1994. If any discrepancy is found, prior to further flight, correct the discrepancy in accordance with the service bulletin.

(b) Within 3,000 landings, or 12 months after the effective date of this AD, whichever occurs first: Install revised tolerance bushings in the bearing cap/bracket attachment assemblies of the NLG retraction actuator, test the actuator for freedom of movement, and inspect for any discrepancy of the actuator, in accordance with paragraph 2.B. of the Accomplishment Instructions of Jetstream Service Bulletin ATP-53-30-10372A, dated November 3, 1994.

(1) If no discrepancy is found no further action is required by this AD.

(2) If any discrepancy is found, prior to further flight, correct the discrepancy in accordance with the service bulletin.

(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 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the 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 actions shall be done in accordance with Jetstream Service Bulletin ATP-53-30-10372A, dated November 3, 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 Jetstream Aircraft, Inc., P.O. Box 16029, Dulles International Airport, Washington, DC 20041-6029. 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 17, 1995.

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 Jetstream Model ATP airplanes was published in the Federal Register on June 12, 1995 (60 FR 30797). That action proposed to require an inspection to ensure that the bearing caps, bolts, and special washers are secure; and an inspection of the bearing cap mounting holes for correct hole and thread length. That action also proposed to require a later inspection for discrepancies of the retraction actuator; installation of revised tolerance bushings; and alignment of the outboard support bracket, if necessary. That action also proposed to require corrective actions for any discrepancy found.

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 10 airplanes of U.S. registry will be affected by this AD, that it will take approximately 17 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will be provided by the manufacturer at no cost to the operator. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $10,200, or $1,020 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 relationshipbetween 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 39Air 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 USC 106(g), 40101, 40113, 44701.

39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: