Would this be counter rotating props?

[Randy Cuberly]

From the thread quoting Randy, "the system was a fluid drive system just like any car is driven by with an automatic trans.
The rear prop will take you finger off  if you stick it in it when running, the  ...ONLY...  time it is freewheeling is when the engine stops."

Thanks for the info Fred.  I was erroneously told be someone that it was only driven by airflow from the front prop.

I would be interested in finding out how the fluid system was set up.  Guess I'll have to ask Randy S. next time I talk to him.

Randy Cuberly