Most common military helicopter

Over 16,000 Bell Helicopter Textron (USA) UH-1 Iroquois ('Huey') helicopters have been produced since 1959, making it the most widely used military helicopter in the world. The general-purpose UH-1 became the workhorse of the US forces in the Vietnam War, with over 5,000 serving as transporters, gunships and air ambulances by the end of the conflict. It is claimed that over 5,000 UH-1s remain in service in over 45 countries.