This was done a couple years ago. Its pretty strong 35knts plus lit on a 7m.
Check the sand moving.
You might need to move the dot on the red bar cause it jams at 6 second. Sorry about the poor quality will do a better one in stronger wind. More of the story in the comments box on the youtube site.
Note the wedged board in the sand.
seabreeze.com.au/gallery/gallery.asp?imageid=6414
