Quote Originally Posted by piper184 View Post
The weight of the hose and water will severely limit the effective height. Not to mention the thrust required to counter the reaction forces from the nozzle.
I was thinking that too. However, it almost appears to me they are spraying something other than water, which could be much lighter in weight.

Still, this is a very impressive concept. Drones could be made as big as needed for work like this. Imagine drones built big enough to set large air conditioning units on top of buildings in place of tall cranes and helicopters?