On May 2, 1985 a group of expert kayakers was finishing the Class V "Giant Gap" run on California's North Fork of the American River. Mark Allen was a very skilled kayaker in excellent physical shape. He was a rodeo champ who had just returned from an extended exploratory trip to Peru. He knew the river extremely well andwas livening up the easy Class III rapids in the runout run by boofing offset boulders. He tried a move to the left of the main chute. He missed his line and his kayak glanced off the upstream rock and pitoned on the one downstream.
Mark was not initially concered. With a bemused expression on his face he tried to work his way free. As the bow broke loose from the downstream rock the kayak instantly wrapped on the upstream one and sank out of sight. The site was hard to reach; one member of the group swam out to the rock but could not offer any real assistance. They paddled out and notified aithorities. A rescue team was able to lower a cataraft in position above the rock and snag the boat with a grappling hook and pull it free. The body was recovered three weeks later.
Source: Gordon Patchin, Lee Miller, Bob Knight, and Keith Beck
1) Side channels of moderate raspids are often much more dangerous than they look. This place was described as "ugly" and "no place I'd want to be." It was clearly a powerful place, and more dangerous than it looked.
2) Kayaks can pin quickly, and the situation can go from bad to worse in an instant. The lack of rigidity in roto-molded kayaks exacerbates the problem and caution is advised.