Ran into a formation of Boston's yesterday & proceeded to give chase. The guy playing seemed to be a new player & pulled his lead plane in for a dog fight.
He extended out & I noticed his drones floating ahead of me so I pursed those I killed one of them & noticed I was 4.5k from the lead plane. 
I have heard people complain about the range the Boston drones can separate from the lead aircraft before.  

4.5K though seems to be a lot to me. 
Thoughts?