I'm not sure where you get 300 feet as a safety altitude. Seems rather arbitrary. If you decide to shoot one down, which is incredibly stupid from a safety standpoint, it will come down in a random direction (and potentially in a powerdive). Doesn't matter where you are, anyone who is generally beneath it will be at risk. Just think what kind of damage a 5-10 lb object travelling at 50-70 km/hr can do.
And then there is the props. I've seen first hand what a multi rotor prop can do to flesh. It will look like someone has cut a nice neat row of fish gills centimeters deep into you. Depending on where it hits, it can cut to the bone. Some of these props are carbon fiber and they are very strong and sharp.
Bottom line is there is no guarantee of safety with multirotors and Airsoft. Too much can go wrong with the electronics. And players with urges to shoot it down makes it exponentially more dangerous.
Last edited by Fuzzy; January 28th, 2015 at 22:15..