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 4101 airplanes was published in the Federal Register on December 19, 1995 (60 FR 65258). That action proposed to require replacement of the flexible cables of power and condition controls of the engines with new flexible cables. The action also proposed to require installation of protective tape on the outside case of the new flexible cables of the power and condition controls of the engines, and reidentification of the assembly number of the cable.
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 Provide Additional Terminating Action
One commenter requests that the FAA revise the proposal to require the accomplishment of the actions described in Jetstream Service Bulletin J41-76-013 () (Modification JM41485A), as interim action only. The commenter states that the flexible cables associated with the proposed action have a life limit of 6,000 hours time-in-service, and have not demonstrated reliability warranting an escalation of this limit. Instead, the commenter requests that the proposal be revised to include a requirement to accomplish the actions described in Jetstream Service Bulletin SB J41-76-014 () (Modification JM41478), as the terminating action. The new improved flexible cable, which is associated with Modification JM41478, holds the promise of eventually qualifying for an escalation of its life limit to 12,000 hours time-in-service.
The FAA does not concur with the commenter's request to revise the AD. The FAA has determined that accomplishment of the procedures specified in Jetstream Service Bulletin J41-76-013, as proposed, adequately addresses the identified unsafe condition by preventing heat damage and moisture contamination to the flexible cables.
The FAA recognizes that some operators previously may have elected to accomplish Modification JM41478, which the FAA considers to addresses the identified unsafe condition adequately as well. However, the FAA points out that this AD is applicable only to Model 4101 airplanes on which Modification JM41478 or JM41485A has not been installed. Therefore, those airplanes are not subject to the requirements of this AD.
Request to Require Marking of Part Numbers
This commenter also requests that the FAA revise the proposal to require marking part numbers on the two types of engine control cables (Modifications JM414485A and JM41478) after installation of the cables. The commenter states that routing during installation of the cables requires removal of all identification bands, making verification in the absence of good recordkeeping virtually impossible.
The FAA does not consider a revision to be necessary. The FAA points out that paragraph (a)(2) of the final rule already requires reidentification of the assembly number of the cable. Since this AD does not require Modification JM41478, as stated previously, the FAA finds that including a requirement for such a marking need not be specified in this final rule.
Request to Revise Cost Impact Information
This same commenter asserts that the cost estimate presented in the preamble of the proposal was incorrect. The commenter notes that the FAA estimates that 25 airplanes of U.S. registry would be affected by this proposed AD; however, the commenter states that it currently operates 25 airplanes of U.S. registry, and knows that there are additional U.S. operators.
In addition, the commenter states that the required modification would necessitate 39 work hours, rather than the 11 work hours specified in the proposal.
After considering the data presented by the commenter, the FAA concurs that the number of U.S.-registered airplanes affected by the AD, and the number of necessary work hours, are higher than approximated previously. The FAA has revised the cost impact information, below, accordingly.
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 to the cost impact information described previously. The FAA has determined that these changes will neither significantly increase the economic burden on any operator nor increase the scope of the AD.
Cost Impact
The FAA estimates that 44 airplanes of U.S. registry will be affected by this AD, that it will take approximately 39 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will be supplied by the manufacturer at no cost to the operators. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $102,960, or $2,340 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.
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: