21st SOS

The 21st Special Operations Squadron (21st SOS) is a distinguished unit of the United States Air Force, originally constituted as the 21st Troop Carrier Squadron in 1942. The squadron has participated in numerous operations, including critical airlift missions during World War II, the Vietnam War—where it became known for its CH-3 and CH-53 "Jolly Green Giant" helicopter operations—and more recent deployments supporting global special operations. Redesignated as a special operations squadron in 1967, the 21st SOS has operated a variety of aircraft, specializing in infiltration, exfiltration, and resupply of special operations forces. Today, the unit is based at Yokota Air Base, Japan, and continues to provide vital support for U.S. and allied special operations in the Indo-Pacific region.