Bell H-13 Sioux
Adopted by the US Armed Forces in 1946, the Bell H-13 Sioux saw extensive use in the Korean Conflict, acting in an observation, reconnaissance, and medical transport role. The H-13 featured a then-revolutionary gyrostabilizer below the main propeller, which increased overall stability and safety of the craft. The Sioux is perhaps most notable for being the first helicopter named after a Native American Tribe, now a longstanding tradition within the US Army. One of the first mass-produced helicopters to see military use in the United States, the Sioux initially flew in the opening stages of the Vietnam War, but became outmoded with the introduction of the newer OH-6 and OH-58.
[1] Olive-Drab. “Bell H-13 Sioux Helicopter,” accessed September 10, 2018.
