A U.S. Air Force helicopter, likely a Sikorsky CH-3 or HH-3E 'Jolly Green Giant,' banks through a hazy sky while releasing a trail of colored smoke or marking dye. Aircraft of this type served as the backbone of Air Force combat search-and-rescue operations during the Vietnam War, often escorted into hostile territory by A-1 Skyraider 'Sandy' aircraft to recover downed airmen. Project: 218934