Looks like a small flat kite to me.
Quite surprised that everyone has not gone this route.
Be interesting to see how much wind they can carry it up wind.
And at what point loosing area kills them down wind.
It is a risk for them, I know they changed the minimum wind rule for the Ollies this time, but not sure how low they will race in.
I assume it still passes the 75% girth rule. It looks like it does.
Good thinking batman!