FCS fin manufacturing - Chinese factory video

[jspr]

Hey Stoneburner , thanks for helping out!
Took some time to read through.
I’m not sure if I understand the below regarding the distance between the fins:

“this shows indeed that fins close to each other should have roughly the same size as the single fin. While a twin fin on the rails can reduce the fin size to almost half the size.”
Below the quote from the OG post…

@hans

this shows indeed that fins close to each other should have roughly the same size as the single fin. While a twin fin on the rails can reduce the fin size to almost half the size.

However, the further the fins apart, the less the positive effect of the inside fin (~ upper wing) on the stall angle of the outside fin.

The statement that you can use more upright fins also makes sense. Sweep in single fins soften the stall by twisting and therefore reducing the AOA at the tip. And since the Thraikill fin setup softens the stall angle by the fin interaction, less sweep is needed. The more upright shape may result in a looser feeling.

This fin setup makes perfect sense to me. However I’d go for double foiled fins since the inside fin (~ top wing) is responsible for more than half the lift generated.