U.S. Air Force Combat Controllers - GAU-5A Carbine
A vintage (1988) shot of USAF Combat Controllers (CCTs) from the 1722nd Combat Control Squadron.
The foremost CCT is armed with a GAU-5A carbine.
The GAU-5A is the USAF variant of the Colt CAR-15 Commando (Model 610).
Note the CCTs in the background using a weather balloon to measure wind speed in preperation for an airdrop.