The furthest distance away from the beach I sail is in Poole Harbour where the best spot is 2 miles away on the other side of the harbour.
I only go over there when the forecast is sound and my smallest board I take there is 110l & 6.5m sail. I've had the wind die on me and its taken 30 minutes to get back. But that was still 8 knots of wind. I doubt I will be going over there on the foil as thats light winds to start.
Nils Bach takes that a bit further here. He had to de-rig and use the mast to paddle back.
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