Examining the Docket \n\n\tYou may examine the airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Operations office (telephone (800) 647-5527) is located on the ground floor of the West Building at the street address stated in the ADDRESSES section. \n\nDiscussion \n\n\tThe FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to certain McDonnell Douglas Model 717-200 airplanes. That NPRM was published in the Federal Register on February 14, 2007 (72 FR 6973). That NPRM proposed to require installing a certain junction(s) and changing the wiring of the first officer's pitot static heater system. \n\nComments \n\n\tWe provided the public the opportunity to participate in the development of this AD. We have considered the comments received. \n\nSupport for the Proposed Rule \n\n\tAirTran Airways and the National Transportation Safety Board support the proposed actions as described in the NPRM. \n\nRequest To Revise "Relevant Service Information'' Section of the NPRM \n\n\tBoeing requests that we revise the "Relevant Service Information'' section of the NPRM to include the following wording: "The service bulletin describes procedures for changing the first officer's pitot heater wiring to separate the first officer's pitot sensor heater ground from the captain's and auxiliary pitot sensor heater grounds. In addition, to meet system independence, the captain, first officer, and auxiliary pitot sensor's heaters are also activated using the air/ ground sensing system.'' Boeing explains that there are more electrical parts than just the "junction'' to re-wire this system. The revision clarifies the subsequent actions in the service bulletin. \n\n\tWe agree that the suggested wording adds clarification. However, since that section of the preamble does not reappear in the final rule, no change to the final rule is necessary. \n\nRequest To Revise Paragraph (f) of the NPRM \n\n\tBoeing also requests that we revise paragraph (f) of the NPRM to delete the reference to only one electrical component. Boeing explains that there are several electrical items (delete wire, add new wire, sockets, junction, etc.) to implement the wiring changes to this system, and that it is only necessary to refer to Boeing Alert Service Bulletin 717-30A0003, Revision 2, dated November 28, 2006, for this information. (We referred to Boeing Alert Service Bulletin 717-30A0003, Revision 2, in the NPRM as the appropriate source of service information for accomplishing the required actions.) \n\n\tWe agree with Boeing that there are several electrical items required to implement the wiring changes specified in paragraph (f) of the NPRM. The paragraph, as stated in the NPRM, did not include all of those items. We also agree that referring only to the service bulletin in that paragraph will ensure that all items are included. Therefore, we have revised paragraph (f) of this AD to state: "Within 24 months after the effective date of this AD, change the wiring for the air data sensor heating system, by accomplishing all the actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 717- 30A0003, Revision 2, dated November 28, 2006.'' \n\nClarification of Alternative Method of Compliance (AMOC) Paragraph \n\n\tWe have revised this action to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies. \n\nConclusion \n\n\tWe have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCosts of Compliance \n\n\tThere are about 155 airplanes of the affected design in the worldwide fleet. This AD affects about 123 airplanes of U.S. registry. The actions take between 4 and 16 work hours per airplane depending on the airplane configuration, at an average labor rate of $80 per work hour. The manufacturer states that it will supply required parts to the operators at no cost. Based on these figures, the estimated cost of the AD for U.S. operators is between $39,360 and $157,440, or between $320 and $1,280 per airplane, depending on the airplane configuration. \n\nAuthority for This Rulemaking \n\n\tTitle 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority. \n\n\tWe are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III,Section 44701, "General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. \n\nRegulatory Findings \n\n\tWe have determined that this AD will not have federalism implications under Executive Order 13132. This AD 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. \n\n\tFor the reasons discussed above, I certify that this AD: \n\n\t(1) Is not a "significant regulatory action'' under Executive Order 12866; \n\n\t(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\n\t(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. \n\n\tWe prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\nAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\nSec. 39.13 (Amended) \n\n2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by adding the following new airworthiness directive (AD):