Cold Seas VS Warmer Seas

[Matt]

I had a back to back session moving from one spot to another with 10C difference in temp, described here:

AFS Silk - Demo ride report

cool, I had the most bizarre experience on the silk 850. Monday, felt super dialled, very happy. Wednesday, new spot, felt completely foreign, really struggling to link waves, stalling etc. The difference, moving to a ~10°C colder spot. 22°C to 13°C. Spring-suit to 4/3mm. The feeling was as if there was less lift, but also more drag! Turns felt fine, maybe smoother, but needed more power in the waves. Could partially put this down to the extra neoprene, but it felt radically different, a…

After a few more sessions, I have the following theory about colder water

1. It dramatically reduces the lift of the foil
2. It does not decrease the drag of the foil, and more importantly, does not decrease the mast drag

The outcome is that the same setup in colder water is more sensitive to riding low on the mast.

This is most noticeable on a high aspect foil where 30cm of additional mast drag could possibly double the total drag.