If you leave your race board sitting on the beach for any period then you need to have the fins facing downwards.
The fins are super sharp and it is only a matter of time before a kite gets damaged, or even worse a kiter or beach walker gets injured by the fins.
I am seeing lots of newbie race board riders turning up at the beach. They give it a bit of a go before swapping for their regular board. The race board is often left sitting by the water with 3-4 30-40 cm razor sharp fins sticking up. This is a very bad thing.
If you want to leave your board on the beach then carefully place the fins down into the sand. It won't damage the fins as long as you're careful. It certainly hasn't damaged my fins at all. Alternatively, take the time to pack your board away and put it in the car.
They're usually made out of G10. They're pretty tough.
That's kind of irrelevant. It's unacceptable to leave razor sharp blades sticking up on the beach. It's easy enough to keep them fins down without breaking them, or put covers on them if you must have them pointing upwards.
IF you leave your board fins down point the nose into the wind :) boards caught in the wind and cartwheeling down the beach can also be dangerous :)
Thats in reference to a true event where my board went slicing and dicing down the beach! Also with fins down, watch out for the local kids that think that the board is a ramp to use for running up and jumping off .. apparently for the amusement of their parents.