Green. Other than minor roles in World War Two, the helicopter wasn't utilized until the Korean conflict when the Bell H-13 Sioux, OH-23 Raven, and Sikorsky H-19 Chickasaw became operable. U.S. military helicopters started to make an impact during the Vietnam War to assist in combat as well as search and rescues. This heavily illustrated book provides detailed insight into the transformation of the helicopter and how it evolved. 224 pages, 250 B&W and color photographs, softcover.
