Hi,
There is a guy here in Sweden that has Sebart PrometheuS biplane and he has flown it.
He use Hacker Adverrun contra system. Link to his post on a Swedish modelflying forum:
Svenskt Modellflyg
If You want to know what he is writing just copyt and paste above URL into Google translator
from Swedish to Your own language. I testad and it works fine.
Hopefully I will see it fly at our first F3A competition here in Sweden May 27-28.
/Bo