In his book, "Deep Survival: Who Lives, Who Dies, and Why," Laurence
Gonzalez details at least two incidents in which whales came up from
below and whacked small vessels at sea. In both cases, the vessels
were destroyed and sent the crew into survival mode so fast that, in
one case, the lone crew member had to risk his life to get to his
emergency supplies as the boat began to sink, and in the other, the
five crew were WITHOUT ANY supplies, including water, for five days.
Three died in that case.

In both cases, the whales struck the vessels during storms. This may
mean it is only a whale behavior that occurs in unusual, disorienting
conditions. But either way: oceangoing sailors of moderate-sized to
small vessels: WATCH OUT! This is one thing you normally DO NOT
PREPARE FOR!


http://www.deepsurvival.com/