I'm watching this show on NGC about Tsunami. It talked about one that happened I think in Alaska in 1958. A landside dumped a lot of land into a a narrow body of water which produced a wave over 1,000' moving at 70 mph. There were 3 boats in the area. One boat survived. The survivor said that they were anchored when it hit and that they just started the motor and headed directly into the wave. He said the boat just rode up the 1,000' wave and down the other side while breaking the anchor chain. Now I'm under the impression that science says a boat can't go over a wave of 70 degrees that is larger then the boat because of the gravitational pull on the boat can't be overcome by the engine. Wouldn't a Tsunami wave be steeper then 70 degrees?