When Maverick is talking to Charlie about his family, he says after his father was shot down that his mother used to listen to "Dock Of The Bay" over and over. Dock Of The Bay was'nt released yet at the time his Dad was shot down
When was his dad shot down? I don't recall it stating specifically when that happened. "Dock of the Bay" was released in 1968, so it's definitely conceivable his dad was shot down right around that time (during the Vietnam War).