Airworthiness Directives; Various Restricted Category Helicopters

We are adopting a new airworthiness directive (AD) for Arrow Falcon Exporters, Inc. (previously Utah State University); Firefly Aviation Helicopter Services (previously Erickson Air-Crane Co.); California Department of Forestry; Garlick Helicopters, Inc.; Global Helicopter Technology, Inc.; Hagglund Helicopters, LLC (previously Western International Aviation, Inc.); International Helicopters, Inc.; Precision Helicopters, LLC; Robinson Air Crane, Inc.; San Joaquin Helicopters (previously Hawkins and Powers Aviation, Inc.); S.M.&T. Aircraft (previously US Helicopters, Inc., UNC Helicopter, Inc., Southern Aero Corporation, and Wilco Aviation); Smith Helicopters; Southern Helicopter, Inc.; Southwest Florida Aviation International, Inc. (previously Jamie R. Hill and Southwest Florida Aviation); Tamarack Helicopters, Inc. (previously Ranger Helicopter Services, Inc.); US Helicopter, Inc. (previously UNC Helicopter, Inc.); West Coast Fabrication; and Williams Helicopter Corporation (previously Scott Paper Co.) Model HH-1K, TH-1F, TH-1L, UH-1A, UH-1B, UH-1E, UH-1F, UH-1H, UH-1L, and UH-1P Helicopters; and Southwest Florida Aviation Model UH-1B (SW204 and SW204HP) and UH-1H (SW205) Helicopters. This AD requires inspecting each affected tail rotor blade (blade) forward tip weight retention block (tip block) and the aft tip closure (tip closure) for adhesive bond voids and removing any blade with an excessive void from service. This AD also requires modifying certain blades by installing shear pins and tip closure rivets. This AD was prompted by reports of missing tip blocks or tip closures, resulting in minor to substantial damage to blades installed on Bell Model 212 and 412 helicopters. The actions are intended to prevent loss of a tip block or tip closure, loss of a blade, and subsequent loss of control of the helicopter.