can drones be put into fleets ?

[Ragnarok-X]

Problem:

i recently discovered drones. I thought they are okay, and got a few constructed in a system which is shared between an AI and me. I decided to make antiplanet drones, launch them from my planet and attack the next hostile planet.
The problem is that my drones seem to attack one after another and can thereby be shot down very easily by the PDS. Is there way to make more than one drone attack in the same combat (not using drone launchers IN combat)

I think drones are supposed to be ballistic missiles, so why cant you simply launch a volley of nuke missiles ?!

ty