People who are immediately dead float, and this is all depending on body type and boyancy. bodies will sink, inevitably. In the olden days, and even today, small explosions are let off under water to make dead bodies float. (the old timers used canon fire) This disruption would cause dead bodies to float upward as the watter is immediately more deance than tissue, and the water is dispersed or knocked out of the tissue momentarily. But yes, bodies usually float for few hours first. I would quote something outta wiki, but I think tom Sawyer is a more reputable source![]()