I've recently gotten into FPV quadcopter flying. Thrust to weight is insane. 0-60mph is like one second on my 5". I'm getting to the point where I could attach a spear to the front and have a good chance at chasing someone around obstacles and hitting them. If you've seen drone racing or freestyle you know the speed and precision a good pilot can get out of these things.
Larger drones typically don't perform like this but they could with proper engineering to scale the powerplant proportionally. A 500 lbs all-up machine using independent collective pitch on 4 props powered by a small turboshaft should have similar maneuverability to a 5" racer. With a 100lbs weapons payload it could be absolutely devastating. Basically it's an attack helicopter with 7g of acceleration whenever you want it... from hover even. And it can fly through anything from a garage door to a window depending on how you scale it. Being unmanned, survivability isn't necessary and may not even be desirable.
There are projects to use vision based AI to pilot these aircraft in a manner similar to human pilots. DRL has the AIRR program.
If this AI gets good enough a wave of 5" drones with hunting broadheads affixed to the nose would be terrifying. Scale up a little and add machine guns, EFPs, fragmentation, HEAT munitions, etc. Alfred Hitchcock's "The Birds" comes to mind.
These commie machine gun dogs wont stand a chance.
image 200 of these doing 60mph weighting like 4 lbs and all programmed into slamming into a human
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