Hi Raymond
The gun on this aircraft is situated on top of the fuselage where it blends with the wing, on either on the port or starboard (I forget!)above and behind the pilot.
I saw a fairly similar display at an air show in South Africa, back in '96, was an incredible spectacle and definitely one of the highlights to a great show!
Its not FBW, in fact I dont believe the Soviets have any FBW aircraft?
Cheers
Ant