Swiss sailor Bernard Stamm says his IMOCA 60 race yacht broke in half and sank after being hit by a wave in the height of what was named Storm Dirk.
Stamm was rescued on Christmas Eve after the accident, which saw him and his co-skipper Damien Guillou swimming for their lives in huge seas some 170 miles south-west of the Scilly Isles.
The pair repeatedly had to enter the water in darkness during several attempts to airlift them and later to transfer to a cargo ship.
"We were a little ahead of the front, downwind. There was a steady 43-45 knots [of wind], but it was manageable,” Stamm told the British magazine Yachting & Boating World. “We were prepared for this gale. We were under storm jib, with four reefs in the mainsail. Clearly, we really had the handbrake on, but in a wave the boat broke in two just behind the daggerboards.”