A proposal to amend 14 CFR part 39 to include an AD for the specified model helicopters was published in the Federal Register on July 16, 2007 (72 FR 38797). That action proposed to require replacing a certain bolt with an airworthy bolt. That action also proposed establishing a retirement life for certain bolts and recording the retirement life on a component history card or equivalent record. \n\n\tTransport Canada, the airworthiness authority for Canada, notified the FAA that an unsafe condition may exist on BHTC Model 430 helicopters, serial numbers 49001 through 49106. Transport Canada advises of the need to establish a new airworthiness life limitation of 5,000 hours for the three servo actuator support attachment bolts and to replace the three affected bolts. \n\nBell Helicopter Textron has issued Alert Service Bulletin No. 430- 05-33, dated February 16, 2005 (ASB). The ASB introduces a retirement life of 5,000 hours for the bolts. The ASB states thatsince these bolts have not been listed in the Helicopter Component Replace record, it is difficult to determine with accuracy the actual number of hours accumulated on fielded bolts. Also, the ASB states that Bell has elected to replace all the fielded bolts, part number (P/N) 50-047C8-31. Transport Canada classified this ASB as mandatory and issued AD No. CF-2005-09, dated April 14, 2005, to ensure the continued airworthiness of these helicopters in Canada. \n\n\tThis helicopter model is manufactured in Canada and is type certificated for operation in the United States under the provisions of 14 CFR 21.29 and the applicable bilateral agreement. Pursuant to the applicable bilateral agreement, Transport Canada has kept us informed of the situation described above. We have examined the findings of Transport Canada, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States. \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed with two changes. We corrected a paragraph under the ADDRESSES section in the preamble to reflect the correct address for getting the service information. Also, we added a Note to the AD stating that there is service information that pertains to the subject of the AD. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\n\tWe estimate that this AD will affect 54 helicopters of U.S. registry, and the required actions will take about 2 work hours per helicopter to replace 3 bolts at an average labor rate of $80 per work hour. Required parts will cost about $243 for each bolt. Based on these figures, we estimatethe total cost impact of the AD on U.S. operators to be $ $48,006, assuming that the recordkeeping cost would be negligible. \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 the regulation: \n\n\t1. Is not a "significant regulatory action'' under Executive Order 12866; \n\n\t2. Is not a "significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\n\t3. 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 an economic evaluation of the estimated costs to comply withthis AD. See the AD docket to examine the economic evaluation. \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\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Safety. \n\nAdoption of the Amendment \n\nAccordingly, 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: \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. Section 39.13 is amended by adding a new airworthiness directive to read as follows: