unmanned attack helicopter

there’s a lot of talk about the use of unmanned combat aircraft
but I was wondering, how effective would an unmanned attack helicopter be?

something small and light, so it can be cheap and fast, hard to target
it would act more as a forward scout and hit and run

there’s also the A-160 that was used by US special forces, but the program was “officially” abandoned in 2012

and this armed Schiebel

and this beauty