this is also works with support class if you want to duplicate the juggernaut or osprey gunner. 1 class with the osprey or juggernaut, and the 2nd class also has to be support with the UAV. Its easier if you just use UAV only for the 2nd class and leave the other 2 killstreaks slots blank
with the osprey gunner before you use another osprey you have to wait for the first osprey to get destroyed or disappear otherwise if you attempt to use it while its flying you will get a UAV instead.