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 Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif 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 all McDonnell Douglas Model DC-10-10, DC-10-10F, DC-10-15, DC-10-30, and DC-10-30F (KC-10A and KDC-10) airplanes; Model DC-10-40 and DC-10-40F airplanes equipped with Pratt & Whitney JT9-20 or JT9-20J engines; and all Model MD-10-10F and MD-10-30F airplanes. That NPRM was published in the Federal Register on October 13, 2006 (71 FR 60448). That NPRM proposed to require replacing the control modules of the fire detection systems of the propulsion engines with new, improved control modules. \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 NPRM \n\n\tFedEx concurs with the NPRM as written and states its intent to also modify the fire detection systems of the auxiliary power units of subject FedEx airplanes, as described in the service information mandated by the AD. \n\nRequest To Clarify Service Information Requirement \n\n\tHawaiian Airlines requests that we revise the NPRM to clarify what service information is acceptable for compliance with the AD. The commenter asserts that the NPRM states that the use of Meggitt Safety Systems Service Bulletin 26-34, Revision 2, dated August 15, 2006, is acceptable for compliance. However, the commenter states that, according to Revision 1 and Revision 2 of the service bulletin, no further work is required. Therefore, the commenter inquireswhether compliance with the original issue or Revision 1 of the service information will be acceptable. \n\n\tWe partially agree. Although we can find no statement in Service Bulletin 26-34, Revision 1, dated July 17, 2006 (which is the original issue); or Revision 2; that no further work is required, we have confirmed that Revision 1 and Revision 2 are technically identical and differ only in issues of format and style. Therefore, we have added new paragraph (g) to the AD to specify that actions accomplished before the effective date of the AD in accordance with Revision 1 of Service Bulletin 26-34 are acceptable for compliance with the requirements of the AD. We have re-identified subsequent paragraphs of the AD accordingly. \n\nRequest To Include Statement of Intent To Incorporate by Reference \n\n\tThe Modification and Replacement Parts Association (MARPA) requests that, during the NPRM stage of AD rulemaking, the FAA state its intent to incorporate by reference (IBR) any relevant service information. MARPA states that without such a statement in the NPRM, it is unclear whether the relevant service information will be incorporated by reference in the final rule. \n\n\tWe do not concur with the commenter's request. When we reference certain service information in a proposed AD, the public can assume we intend to IBR that service information, as required by the Office of the Federal Register. No change to the AD is necessary in regard to the commenter's request. \n\nRequest To Post IBR Documents on the Docket Management System (DMS) \n\n\tMARPA asserts that IBR documents should be made available to the public by publication in the DMS, keyed to the action that incorporates them. MARPA therefore requests that such documents be published in the DMS prior to release of the final rule. \n\n\tWe do not agree with this request. We are currently in the process of reviewing issues surrounding the posting of service bulletins on the DMS as part of an AD docket. Once we have thoroughly examined all aspects of this issue and have made a final determination, we will consider whether our current practice needs to be revised. No change to the AD is necessary in this regard. \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 305 airplanes of the affected design in the worldwide fleet. This AD affects about 233 airplanes of U.S. registry. The required actions take about 6 work hours per airplane, at an average labor rate of $80 per work hour. Required parts cost about $9,900 per airplane. Based on these figures, the estimated cost of the AD for U.S. operators is $2,418,540, or $10,380 per airplane. \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 substantialdirect 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):