Sub Lt. David Balme, the Royal Navy officer who led the boarding party on "U-110", called "U-571", "a great film" and said that it would not have been financially viable without being ""americanised"". The film's producers did not agree to his request for a statement that it was a work of fiction, but the end credits dedicate the film to the "Allied sailors and officers who risked their lives capturing Enigma materials" during the Second World War. The credits acknowledge the Royal Navy's role in capturing Enigma machines and code documents from "U-110", " U-559" and the U.S. Navy's capture of "U-505".