The Boeing, Airbus Helicopters, Kaman, Bell Helicopter Textron, AgustaWestland, MD Helicopters, Russian Helicopters, Sikorsky Aircraft, Enstrom Helicopter Corporation, Korea Aerospace Industries, Hindustan Aeronautics, Robinson Helicopter Company, Turkish Aerospace Industries, Dynali, Kawasaki Heavy Industries, Ltd Aerospace Company, Fuji Heavy Industries, Changhe Aircraft Industries, Qingdao Haili Helicopter, NH

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