
30 degrees AOA .
30 degrees AOA is probably most common configuration when sailing square cross wind. Using example from previous post: 25kt board speed, true wind 25kt at 90 degrees and apparent wind 35kt at 45 degrees. To achieve 30 AOA you need to position your sail at 15 degrees relative to the board. Here is link for apparent wind calculator: http://l-36.com/polar_calculate.php?flag=30&flagw=10&tail=15&wdir=90&wd=T&wspeed=25&ws=T&bs=25. So, nothing unusual, very close to real life sailin

40 degrees AOA Hi Load.
Hi load in windsurfing is not unusual. Just an example: if sailing 90 degrees, true wind - 25kt, with board speed 25kt, apparent wind will be at 45 degrees. In order to achieve AOA 40, relative angle of the sail to the board needs to be 5 degree. This is a real life situation which sailors experience probably every session, when excessive oversheeting occurs (unless sailing steep downwind). Let’s take a look how comparing airfoils take Hi load AOA. Image below shows thin a

High load, 50 degrees AOA (Angle of Attack), accelerated stall.
I have to say that Lüderitz-Speed challenge organizers put last year’s (2017) event in much better light. Channel is wider, safer and media coverage was much better. I choose Lüderitz for this blog because this is where sailing is done with super high loads under critical angle of attack. By the way, Mariam Rasmussen (on the picture above) posted on Facebook that coming down through the channel was surprisingly easy. This is how it feels when all aspects of extreme are put