May 10, 1972 was the biggest day of air combat in the Vietnam War. F4 Phantoms, F-105s, and other aircraft descend on North Vietnam on May 10, 1972-the biggest day of air combat in the war.May 10, 1972 was the biggest day of air combat in the Vietnam War. F4 Phantoms, F-105s, and other aircraft descend on North Vietnam on May 10, 1972-the biggest day of air combat in the war.