AD 2000-02-02

Effective February 29, 2000.

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of February 29, 2000.

The service information referenced in this AD may be obtained from Short Brothers, Airworthiness & Engineering Quality, P.O. Box 241, Airport Road, Belfast BT3 9DZ, Northern Ireland. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

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 all Short Brothers Model SD3-60 SHERPA, SD3-SHERPA, and SD3-30 series airplanes was published in the Federal Register on October 6, 1999 (64 FR 54237). That action proposed to require replacement of existing oxygen system “O” rings with improved wear-resistant “O” rings.

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

One commenter requests that the applicability of the proposed AD be revised to include only those Model SD3-30 series airplanes on which an oxygen system is installed. The commenter states that only one variant of these airplanes was delivered in this configuration, and provides a list of the applicable serial numbers. The commenter notes that these serial numbers are also listed in Shorts Service Bulletin SD330-35-1, dated February 25, 1999, which is referenced as the appropriate source of service information in the proposed AD.

The FAA concurs that the requirements of the AD are applicable only to those airplanes on which an oxygen system is installed. The FAA has limited the applicability for Model SD3-30 series airplanes to those listed in Shorts Service Bulletin SD330-35-1, dated February 25, 1999, and has revised the Summary section of the AD to refer to “certain,” rather than “all,” Model SD3-30 series airplanes.

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 with the change described previously. The FAA has determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD.

The FAA estimates that 62 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 actions, and that the average labor rate is $60 per work hour. Required parts will be provided by the manufacturer at no cost to operators. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $186,000, or $3,000 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.

The regulations adopted herein will not have a substantial direct effect 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, it is determined that this final rule does not have federalism implications under Executive Order 13132.

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.

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

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:

1. The authority citation for part 39 continues to read as follows:

2. Section 39.13 is amended by adding the following new airworthiness directive: