This amendment adopts a new AD for the specified BHTC model helicopters. This action requires an initial inspection and certain repetitive checks and inspections of the blade, at specified intervals, for a deformation, a crack, and a bent or deformed weight. Also, this action requires, before further flight, replacing each blade with an airworthy blade if a deformation, a crack, or a bent or deformed weight is found. This amendment is prompted by three reports of skin cracks originating near the blade trailing edge balance weight. In two reports, a loss of the weight and a strip of material along the trailing edge led to an imbalance and fracture of three of the four tail rotor gearbox attachment bolts. In one of these incidents the gearbox shifted resulting in failure of the drive shaft and loss of yaw control. This condition, if not detected, could result in blade failure and subsequent loss of control of the helicopter. \n\n\tBHTC has issued Alert Service Bulletin No. 206-04-100 for Model 206A and B and No. 206L-04-127 for Model 206L series helicopters, both Revision B, both dated May 28, 2004. These service bulletins specify checking and inspecting the blades for a deformation, a crack, and a bent or deformed weight and a one-time inspection by Rotor Blades Inc. in Louisiana, USA, and if the blades pass the one-time inspection, adding a "V" at the end of the serial number. The service bulletins also specify replacing any blade with a deformation, a crack, or bent or deformed weight. \n\n\tTransport Canada, the airworthiness authority for Canada, notified the FAA that an unsafe condition may exist on these helicopter models. Transport Canada advises of three reports of skin cracks originating near the blade trailing edge balance weight. Two of the occurrences caused a loss of the weight and a strip of material along the trailing edge leading to an imbalance, which caused the fracture of three of the four tail rotor gearbox attachments. One of these occurrences resulted in the gearbox shifting that caused failure of the drive shaft and resulting loss of yaw control. Transport Canada classified the alert service bulletins as mandatory and issued AD No. CF-2004-05R1, dated June 28, 2004, to ensure the continued airworthiness of these helicopters in Canada. \n\n\tThese helicopter models are manufactured in Canada and are 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 the FAA informed of the situation described above. The FAA has examined the findings of Transport Canada, reviewed all available information, and determined that AD action is necessary for products of these type designs that are certificated for operation in the United States. \n\n\tThis unsafe condition is likely to exist or develop on other helicopters of the same type designs registered in the United States. Therefore, the FAA is issuing this AD to detect a blade with a deformation, a crack, or a bent or deformed weight and to prevent blade failure and subsequent loss of control of the helicopter. This AD requires the following for the specified BHTC helicopters with certain blade part numbers and serial numbers: \n\n\tBefore further flight, unless accomplished previously, and before installing any blade with an affected part number and serial number, cleaning the blade. Then, using a 10X or higher magnifying glass, inspecting both sides of each blade for a deformation, a crack, and a bent or deformed weight. \n\n\tThereafter, cleaning both sides of each blade and using a 10X or higher magnifying glass, inspecting for a deformation, a crack, and a bent or deformed weight as follows: \n\n\tAt intervals not to exceed 12 hours time-in-service (TIS), or \n\n\tAt intervals not to exceed 24 hours TIS and checking both sides of each blade for a deformation, a crack, and a bent or deformed weightat intervals not to exceed 3 hours TIS between inspections. An owner/operator (pilot) may perform the 3-hour TIS check for deformed or cracked blades and for bent or deformed weights. Pilots may perform these checks because they require no tools, can be done by observation, and can be done equally well by a pilot or a mechanic. However, the pilot must enter compliance with these requirements into the helicopter maintenance records by following 14 CFR 43.11 and 91.417(a)(2)(v). \n\n\tBefore further flight, replacing each blade with an airworthy blade if you find a deformation, a crack, or a bent or deformed weight. \n\n\tThe short compliance time involved is required because the previously described critical unsafe condition can adversely affect the controllability and structural integrity of the helicopter. Therefore, inspecting the blade, for a deformation, a crack, and a bent or deformed weight is required before further flight and at short specified time intervals, and this AD must beissued immediately. \n\n\tSince a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.\n\n\tThe FAA estimates that this AD will: \n\n\tAffect 2194 helicopters. \n\n\tTake about 1/4 work hour for a blade check or inspection and 3 work hours to replace one blade at an average labor rate of $65 per work hour. \n\n\tRequired parts will cost about $5,848 per helicopter. (The service bulletin states that warranty credit will be given based on hour usage on the blade with remaining life hours and other restrictions.) Based on these figures, the total estimated cost impact of the AD on U.S. operators is $21,315,807, assuming 226 checks or inspections and replacing one blade on each helicopter in the fleet. \n\n\nComments Invited \n\n\tAlthough this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. \n\n\tComments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available in the RulesDocket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. \n\n\tCommenters wishing the FAA to acknowledge receipt of their mailed comments submitted in response to this rule must submit a self- addressed, stamped postcard on which the following statement is made: "Comments to Docket No. 2004-SW-12-AD." The postcard will be date stamped and returned to the commenter. \n\n\tThe 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. \n\n\tThe FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final economic evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption ADDRESSES. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Safety. \n\nAdoption of the Amendment \n\n\tAccordingly, 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: