David Chandler "Dave" Lyons (born January 23, 1943) is an American former competition swimmer and Pan American Games gold medalist. Lyons earned a gold medal as a member of the first-place U.S. team in the men's 4×200-meter freestyle relay at the 1963 Pan American Games. At the 1964 Summer Olympics in Tokyo, he swam for the gold medal-winning U.S. team in the preliminary heats of the men's 4×200-meter freestyle relay. Under the 1964 Olympic rules he was ineligible to receive a medal, however, because he did swim in the event final. Lyons later earned both M.B.A. and M.D. degrees.