The C version of the same basic design had a single turboshaft engine with a nose air intake. The shaft from the engine is geared to the main rotors and also to the tail propellers. The engine is both powerfull and reliable, and works at full power all the flight time except in landing. So, fuel consumption is high.
Pilot is well protected at the rear, and frontal vision is remote by visible/IR optical camera.
Radar in the nose is for navigation/shooting rangefinder use.
Only problem I see with it is the rotors... I don't think the tip of a rotor blade can safely exceed the speed of sound, so the never-exceed speed of such a craft would be Mach 1 minus the speed of the rotor tips. Which is a bit of a shame, considering how much speed a XFY Pogo or a Tu-95 could get from their contra-rotating propellers...
Oh, and take-off and landings look difficult. Other than that, love the way it looks man ^_^