A mini-drone helicopter or fixed wing can also kill with kinetic force alone...if targeted at the right place. No onboard projectile or bomb needed! (see my tag line)
I've had a rather large RC helicopter crap itself to death at high RPM and launch a blade at me that hit me in the triangle. The repairs cost about $240 but the blade that hit me didn't even snag a thread on my field jacket. That's an 18" wooden blade at max speed. I was very close when that happened.
There’s a guy who had flown his RC glider to 498mph clocked with a radar gun. Might have hit 550mph when it wasn’t being clocked. I certainly wouldn’t want to be hit with that!
Video at link of glider doing 468mph.