You beat me. I was going to suggest a tidal bore or river current of eight or ten knots.
I have a Pearson 31-2 with a rig and hull similar to a 80's era Tartan 31. Though neither is a true displacement hull at about 18 knots through the water, say being towed by a missile frigate, the suction on the hull would be so great and the wave trough established so deep either would be sucked below the deck line and submerge.
Charlie P. P31-2 #80 CATNAP
To travel hopefully is a better thing than to arrive - R.L. Stevenson
I suspect that, if you should go to the end of the world, you would find somebody there going farther . . . - H.D. Thoreau