I notice there is a new breed of camera drones coming on to the market that you don't actually need to fly any more. There purpose is to follow you filming you as you cycle/ski/ etc filming you from the air. The technology differs slightly between models and brands, but basically you carry a tracker on your wrist and the drone follows you or flies in front or to the side filming you.
Assuming the drone crashed in to someone, surely its obviously negligent to create a device that flies automatically without a pilot, but who would be responsible for the injuries? The operator who rode/drove etc in to an area that was unsafe for the drone or the manufacturer for making something that follows you blindly.
They seem pretty cool though.
My suggestions are not legal advice