Columbia Helicopters, Incorporated, or CHI, is an aircraft manufacturing and operator company based in Aurora, Oregon, United States. They are known for operating tandem rotor helicopters; in present times, exclusively the Boeing Vertol 107 and Boeing 234. These helicopters are used in stream restoration and forestry including Heli-Logging, oil exploration, fire suppression, construction, government support, film production, disaster response and many other activities. In addition the company operates a large FAA Repair Station supporting customers around the world.