From The Stargate Omnipedia


Enhancement modifications applied to an unmanned airborne vehicle (U.A.V.) in which powerful missiles are mounted on both dorsal wings of a U.A.V. This enables Stargate Command to striking a target from the air, using radio control through an active Stargate.


Death Knell - Siler is ordered to outfit a U.A.V. with U.C.A.V. modifications, which Carter later uses to her advantage in helping to take out a Kull warrior after it shoots the U.A.V. out of the sky.