http://www.variprop.com/

Perry Mick is installing, balancing and testing
the Vari Prop on his rotary powered Long Ez.

The pictures, web site and dwgs say it all.

So far it has halved his take off run. That is very,
VERY important with a Canard.

Final testing for top speed and cruise speed fuel burn is
not completed.

Lower cost than a MT or Hoffman around
$8,000. Similar wood blades that cut the weight
and rotational inertia which results in  lower stress
on the gear box output shaft.  IMHO a bit loss in eff.
compared to metal blades due to the thicker wood airfoil
sections required. Especially near the tips.

Paul Lamar