They've restricted the underwater foils by max beam in the up and down position and restricted them underwater by not getting closer than 1.5m under the static waterline. The class doesnt need more rules.
If you check the rules at ISAF or at the A-cat webpage there are no rule or measuring guideline that bans that the foils get closer than 1.5 meters. You can have them as close as you want!
/hakan
