Totally off the point
Many years ago, there was another Rooivalk. A one-off F/W aerobatic machine. ISTR that it had 'interesting' design features, like using wooden pegs instead of pulleys for control cables but it's crowning glory was the propeller. This was a VP unit with a facility for going into beta range on vertical descents, to give the pilot lots of time for clever rolls. Only problem was, it was powered by the engine oil system and as soon as the aircraft went inverted and the sump ran out of oil it went into full beta instantly stopping the aircraft. Made inverted low passes a lot more spectacular than was intended.
OA