Trivia: The number of the (fictional) USS Haynes is DE-181. This number was actually used for the USS Straub - an actual Cannon Class escort destroyer.
Trivia: The scenes on the Haynes were filmed on an actual Buckley Class destroyer escort, the USS Whitehurst (DE 634). A great number of the Whitehurst crew act in the movie as the crew of the Haynes, with the commanding officer Lieutenant Commander Walter R. Smith playing the chief engineer (though on IMDB this role is credited to Robert Boon).