Current drones are slow compared to current fighter aircrafts , so those can be used . Signal jamming can be used to jam their communication with the other drones and the base they are from . If the drones are small , what are they gonna carry then ? Couple of missiles won ' t do much damage against full scale army and really small drones can ' t even carry that . The missiles also have a range limit , so the drones can ' t really shoot from the higher altitudes they can fly . The modern antiair missile systems can shoot up to about 8 km altitudes , so to survive the drones would have to go higher than that , but for example the range of Hellfire missiles is also 8 km , so that would be kind of a problem . Not only that but drones can communicate with other drones to shoot specific targets faster than humans . That ' s possible , but for now none of the military forces of the world has used that kind of system . Drones are also still controlled by humans . Of course drones will develop and at some point it will be feasible to use only drones , but that time is not yet .