The scene in which the USS Alabama is diving for the first time out of dock, the footage is of the real submarine submerging. Tony Scott was following along in a helicopter attaining shots of the ship, herself. When the captain of the Alabama requested that the helicopter cease filming, they submerged, which is what director Tony Scott was hoping for anyway.
The disagreement between Cpt. Ramsey and Lcdr. Hunter over the origin of the Lipizzaner stallions throughout the movie foreshadows and illustrates the fundamental source of friction between the two men, both insisting that their mutually exclusive version of reality is the truth. Ironically, Cpt. Ramsey, (who believes the stallions are Portuguese) or Lcdr. Hunter (who says they are Spanish) are both incorrect. The Lippizaner stallions are in fact Slovenian - they originate from a town called Lipica. However, the horses are generally associated with the Spanish Riding School of Vienna (Austria), so Hunter was technically closer to the truth than Ramsey.
According to a 1995 Premiere magazine article, when Quentin Tarantino visited the set, Washington confronted him about his use of the word "nigger" in his films. Tarantino got embarrassed and wanted to move the conversation to a more private area. Washington said, "No, if we're going to discuss it, let's discuss it now." Washington later said he still felt that Tarantino was "a fine artist".
Quentin Tarantino was brought in to do uncredited "punch-ups" of the dialogue. His major contribution was the comic book bickering. The character name "Russell Vossler" is a reference to Rand Vossler, with whom Tarantino used to work at a video store. See also Pulp Fiction (1994).
Skip Beard, listed as a Technical Advisor, served as the Commanding Officer of the real USS Alabama (SSBN 731). He can be seen in the Board of Inquiry scene. He is the man with no hair sitting next to Jason Robards.
The "Sonar" panels constantly depicted in the film are completely false. The movie versions off a dumbed down pseudo radar screen, complete with a sweeptrack and bears absolutely no resemblance to a broadband passive sonar display. This was done to give the audience a more visual feel for the otherwise auditory science of Sonar operation.
Don Simpson and Jerry Bruckheimer originally offered Val Kilmer one of the headlining roles but he declined. Years later Kilmer noted it was one of the few films that he wished he had agreed to be in. The role offered to Kilmer by Simpson and Bruckheimer was never formally specified.
The cigars that 'Capt. Frank Ramsey' and 'Lt. Commander Ron Hunter' smoke at the beginning of their mission are made by Montecristo. The brand is made in both Cuba and the Dominican Republic, by two totally different companies. But Ramsay's "more expensive than drugs" comment implies that theirs were the Cuban-made variety. Ramsay's cigar of choice throughout the movie is the classic tapered Montecristo #2.
Robert Towne received an urgent call from producers Don Simpson and Jerry Bruckheimer one night regarding a key scene between Denzel Washington and Gene Hackman. They wanted Towne to rewrite the discussion on the nature of war between the two characters, thus setting up a more plausible potential for conflict for the remainder of the film. Such was the urgency of the situation, Towne had to literally dictate his rewrite over the phone to the producers as they recorded his words.
At one point in the film, a sonar operator mentions a Soviet "Akula" class submarine. There are two different Soviet/Russian submarine classes referred to by that name: the Project 971 attack submarine known to the Russians as the Shchuka ("Pike") has the NATO code name Akula. The Project 941 missile submarine, NATO codename Typhoon, is named the "Akula" class in Russian. US Navy personnel would usually use the NATO code-names, so the submarine under discussion is an attack boat.
The Alabama's torpedo tubes are located on either side of its hull instead of the traditional bow and stern positions. This is because her bow, like that of most modern submarines, contains a large passive sonar array.
Toward the end of the film, the VLF antenna is raised. VLF is the acronym for the Very Low Frequency radio spectrum, used by submarines because VLF signals can penetrate up to 40 meters of salt water. This allows submarines to receive messages while submerged. In addition, the very long wavelengths (10 to 100 kilometers) make it impossible to precisely determine the location of a VLF signal.
The name of the submarine is the "Alabama." The University of Alabama's football team is called "The Crimson Tide," once led by famous coach Paul "Bear" Bryant. In the film, "Bear" is the name of the Alabama's captain's dog.
Along with Anatomy of a Murder (1959), Independence Day (1996), and The Dark Knight (2008), this is one of only four films whose purely orchestral soundtracks won the Grammy Award for Best Score despite not being nominated for an Academy Award for Best Original Score.
There is another USS Alabama, a WWII battleship, permanently docked at Mobile Bay, Alabama, that serves as a museum, which has also been occasionally used as a hurricane shelter. Most recently during Hurricane Katrina in which members of 18 museum employee families took shelter during the storm.
The origin of Lippizaner horses resides in 9 stallions and 24 mares of Spanish horses imported by the Archduke Carlos II of Austria in 1580. The Archduke founded the stud farm in Lipizzia (Slovenia). But as Denzel Washington states in the film, the horses are actually Spanish.
Jason Robards, who plays the admiral in the inquiry scene, actually served in the Navy during World War II and received the Navy Cross (though he is not listed in official rolls of Navy Cross winners, despite the claims some - not he - have made).
As Ramsey reviews Hunter's service record 11 November 1959 appears as the character's date of birth. Numerous other events have taken place on 11 November including: birth of General Patton in 1885, President Harding's dedication of the Tomb of the Unknown Soldier in 1921, the beginning of construction of the Naval Base at Pearl Harbor in 1909, the formation of the United States Marine Corps in 1775 and the date Washington became a state in 1889. USS Alabama is based in Washington. General Patton is mentioned in the movie. The actor is actually about 5 years older.
When Capt. Ramsay held a gun to the head of Lt. Peter "Weps" Ince (Viggo Mortensen) and then declined to shoot him, he turned the gun on Petty Officer Hilaire (Scott Grimes). Although Mortensen's son Henry Mortensen (with former wife Exene Cervenka) also appeared in the film, he was born in 1988 and was seven years old at the time. He appeared as Henry Ince, Weps's son, at the birthday party scene very early in the film.
In the prelude, the CNN reporter (played by former NBC correspondent Richard Valeriani) establishes his location as "Reporting live from the French aircraft carrier Foch in the Mediterranean Sea." The carrier's namesake, French General Ferdinand Foch, once notably commented, "Aviation is fine as a sport. But as an instrument of war, it is worthless."
The dockside scene where Captain Ramsey (Gene Hackman) addresses the crew shows the USS Alabama in the background and, after his speech, the crew runs onboard. The sub was actually USS Barbel (SS-580), a conventionally-powered (i.e. non-nuclear) attack submarine originally commissioned in 1959. The sail ("conning tower") is a plywood mock-up that generally matched the real Alabama's. Barbel's original sail not only looked different but had already been removed (the Barbel was about to be scrapped).
After Captain Ramsey Gene Hackman holds a gun to Weps's Viggo Mortensen head, he threatens to shoot a junior sailor, Crewman Ince Henry Mortensen instead. This was played by Viggo Mortensen's real life son Henry. Although never discussed in the film, and not likely not known to Captain Ramsey (he had to read the Crewman's name from his uniform), the father/son connection may have extended to the characters. Both Morgensens were listed in the credits with the last name of Ince.
The only previous film that has been about an American Naval Officer being relieved of command by his Executive Officer was The Caine Mutiny (1954), in which Humphrey Bogart played the Captain. Bogart and Jason Robards, who appears in this film, have both been married to Lauren Bacall.
The radio operator Vossler may be in connection to WW2 Medal of Honor Winner Technical Sergeant Forrest L. Vosler who while on a mission over Germany sustained multiple wounds that impeded his vision but was still able to man the tail gunners position repair his radio by touch alone to send out a distress signal.