921st Tactical Airlift Group The 921st Tactical Airlift Group is an inactive United States Air Force Reserve unit . It was last active with the 433d Tactical Airlift Wing , based at Kelly Air Force Base , Texas . It was inactivated on 1 November 1994 . History . Following the mobilizations in 1961 and 1962 for the Berlin Crisis and the Cuban Missile Crisis , Continental Air Command ( ConAC ) realized that it was unwieldy to mobilize an entire wing unless absolutely necessary . Their original Table of Organization for each Wing was a wing headquarters , a troop carrier group , an Air Base Group , a maintenance and supply group , and a medical group . In 1957 , the troop carrier group and maintenance and supply groups were inactivated , with their squadrons reassigned directly to the wing headquarters - despite the fact that many wings had squadrons spread out over several bases due to the Detached Squadron Concept dispersing Reserve units over centers of population . To resolve this , in late 1962 and early 1963 , ConAC reorganized the structure of its reserve Troop Carrier Wings by establishing fully deployable Troop Carrier Groups and inserting them into the chain of command between the Wing and its squadrons at every base that held a ConAC troop carrier squadron . At each base , the group was composed of a material squadron , a troop carrier squadron , a tactical hospital or dispensary , and a combat support squadron . Each troop carrier wing consisted of 3 or 4 of these groups . By doing so , ConAC could facilitate the mobilization of either aircraft and aircrews alone , aircraft and minimum support personnel ( one troop carrier group ) , or the entire troop carrier wing . This also gave ConAC the flexibility to expand each Wing by attaching additional squadrons , if necessary from other Reserve wings to the deployable groups for deployments . As a result , the 921st Troop Carrier Group was established with a mission to organize , recruit and train Air Force Reserve personnel in the tactical airlift of airborne forces , their equipment and supplies and delivery of these forces and materials by airdrop , landing or cargo extraction systems . The group was equipped with C - 119 Flying Boxcar s for Tactical Air Command airlift operations . The group was one of three C - 119 groups assigned to the 433d TCW in 1963 , the others being the 922d Troop Carrier Group , also at Kelly AFB , and the 923d Troop Carrier Group at Carswell Air Force Base , Texas . Ordered to active duty during the Vietnam War in January 1968 , the unit was assigned to the 349th MAW at Travis AFB , California , although the group ' s headquarters remained at Kelly AFB . The group flew missions to numerous places including England , South Vietnam , South Korea , Thailand , Japan , as well as numerous bases in the United States . In November 1968 , the reservists were informed that their active duty service would be reduced from 24 months to 18 months , the unit was returned to reserve service on 1 June 1969 . In 1971 , the groups aged Flying Boxcars were retired , and replaced by more modern C - 130A Hercules transports . It participated in conducting the USAF ' s C - 130A model Hercules pilot , navigator , flight engineer and loadmaster school . It also trained for tactical airlift missions , participating in joint training exercises . It provided airlift of Department of Defense personnel , supplies , and equipment worldwide . Inactivated in November 1974 , with personnel and aircraft being assigned directly to the 433d TAW .