[srcmap]

One only see a few helicopters at time in typical city skyline.

I wonder what happen if there are just 100 of them on the air at the same time.

[thelittleone]

True. The sound of a single drone is enough to disrupt a nice quiet afternoon sky, imagine 100 multi rotor, large enough to carry multiple people. Like a swarm of giant mosquitoes constantly buzzing around.