Starboard/Severne advice seems to be a Catapult.
http://www.star-board.com/2013/news_...d-cup-day-four
"Dunkerbeck, on the other hand, endured a disastrous heat as he experienced a huge catapult, which resulted in a broken mast"
But AČ broke a X9 too.
Luckier, just before the first heat.