We had an A-cat regatta this week end at Marstrom and guess what....a M20 with curved daggerboards! These boards have more lifting capabilities than the A-class rules allow and at 17-18 knots with the boards fully down it lifts the boat completely from the water. That is not good since it jumps out of the water quite violently and sometimes threws the crew in the water. The boards where longer than they are in the picture but then it started to do the "thing" at 16 knots. When they sail upwind with this only parts of the hull are in the water and that enough to balance the boat, so it is a kind of "semi foiling". It's hard to tell how much foiling you want to get the best performance. The boards are level with the bottom of the hull in the picture.
![[Linked Image]](http://www.webbo.dyndns.org/m20/pict_1.jpg)
/hakan
Definitely need to be able to balance the boat so it is parallel to the water when foiling. Means adjustable AOA on the centreboards. Max lift when not foiling, and less lift when foiling as the increased speed keeps the boat up and out of the water.
Deeper rudders are necessary to ensure you can still steer and these don't ventilate by the hull rising up. T or L on the bottom means they act similar to the tail on the plane by ensuring the pitch of the boat is kept into line and you should be able to adjust this angle.
Moths lift at 7-8 knots of breeze, so more development can be done to bring this down on the M20. A huge amount of drag to have in conditions when not foiling.
