AD 94-15-13

This amendment supersedes Airworthiness Directive (AD) 92-13-01, which currently requires inspecting the nose landing gear (NLG) drag brace assembly for corrosion on certain Aerostar Aircraft Corporation (Aerostar) PA-60-600 (Aerostar 600) and PA-60-700 (Aerostar 700) series airplanes, and replacing any corroded components. It also requires replacing the existing spring and piston with new corrosion-resistant parts. This action requires replacing the NLG drag link assembly with a new assembly of improved design. The Federal Aviation Administration (FAA) has received several reports of frozen moisture in the cylinder of the over-center release system, which has led to nose gear collapse on airplanes already in compliance with AD 92-13-01. The actions specified by this AD are intended to prevent failure of the NLG caused by frozen moisture in the cylinder, which could lead to nose gear collapse and damage to the airplane.

Final rule.

94-15-13 AEROSTAR AIRCRAFT CORPORATION: Amendment 39-8984; Docket No. 94-CE-04-AD. Supersedes AD 92-13-01, Amendment 39-8270.

Applicability: The following model and serial numbered airplanes, certificated in any category:

Model
Serial Numbers
*PA-60-600 (Aerostar 600)
60-0001-003 through 60-0608-7961195
PA-60-600 (Aerostar 600)
60-0614-7961196 through 60-0933-8164262
*PA-60-601 (Aerostar 601)
61-0001-004 through60-0605-7962136
PA-60-601 (Aerostar 601)
61-0611-7962137 through 61-0880-8162157
*PA-60-601P (Aerostar 601P)
61P-0157-001 through61P-0610-7963274
PA-60-601P (Aerostar 601P)
61P-0612-7963275 through 61P-0859-8163455
PA-60-602P (Aerostar 602P)
62P-0750-8165001 through 60-8365021
PA-60-700P (Aerostar 700P)
60-8423001 through 60-8423025

* = that have been converted to Wiebel nose gear system (Option No. 199)

NOTE 1: The manufacturing and ownership rights of the affected model airplanes were previously owned by the Piper Aircraft Corporation, but these rights were recently transferred to the Aerostar Aircraft Corporation.

Compliance: Required within the next 100 hours time-in-service after the effective date of this AD, unless already accomplished.

To prevent failure of the nose landing gear (NLG) caused by frozen moisture in the cylinder, which could lead to nose gear collapse and damage to the airplane, accomplish the following:

(a) Replace the existing NLG drag link assembly, P/N 450563-1, with a new assembly of improved design, P/N 450563-501, in accordance with the instructions to Aerostar Kit No. 045-001 (Service Kit No. SB600-128), Drawing No. 89414, Rev. N/C, dated December 28, 1993.

(b) 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.

(c) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue, S.W., Renton, Washington 98055-4056. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

(d) The replacement required by this AD shall be done in accordance with the instructions to Aerostar Kit No. 045-001 (Service Kit No. SB600-128), Drawing No. 89414, Rev. N/C, dated December 28, 1993. 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 the Aerostar Aircraft Corporation, Customer Service Department, South 3608 Davison Boulevard, Spokane, Washington 99204. Copies maybe inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(e) This amendment (39-8984) supersedes AD 92-13-01, Amendment 39-8270.

(f) This amendment becomes effective on September 12, 1994.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain Aerostar PA-60-600 (Aerostar 600) and PA-60-700 (Aerostar 700) series airplanes was published in the Federal Register on April 1, 1994 (59 FR 15348). The action proposed to supersede AD 92-13-01 with a new AD that would require replacing the existing NLG drag link assembly, part number (P/N) 450563-1, with a new assembly of improved design, P/N 450563-501. The proposed actions would be accomplished in accordance with the instructions to Aerostar Kit No. 045-001 (Service Kit No. SB600-128), Drawing No. 89414, Rev. N/C, dated December 28, 1993.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed rule or the FAA's determination of the cost to the public.

After careful review of all available information, the FAA has determined that airsafety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. The FAA has determined that these minor corrections will not change the meaning of the AD nor add any additional burden upon the public than was already proposed.

The FAA estimates that 700 airplanes in the U.S. registry will be affected by this AD, that it will take approximately 5 workhours per airplane to accomplish the required action, and that the average labor rate is approximately $55 an hour. Parts cost approximately $1,500 per airplane. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $1,242,500. This figure is based on the assumption that no affected airplane operator has accomplished the proposed action. The FAA believes that numerous operators have already incorporated the modification referenced in this proposed AD.

In addition, AD 92-13-01 requires installing a new spring and piston. The new NLG drag link assembly includes the improved design piston and spring. Aerostar will give a $96 credit for the piston and spring installed as required by AD 92-13-01. Aerostar has shipped 362 of these piston and spring kits. Based on these figures, the cost referenced above would be reduced by $34,752 (362 airplanes X $96) from $1,242,500 to $1,207,748.

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 copy of the final evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.

Section 39.13 -[AMENDED]
2. Section 39.13 is amended by removing AD 92-13-01, Amendment 39-8270 (57 FR 23135, June 2, 1992), and by adding a new airworthiness directive to read as follows: