History Trivia / DownPeriscope

** Creator/PattonOswalt had to leave filming two weeks early so he could start a writing gig on Series/MadTV. Unconcerned, David Ward filmed Patton walking away from his station down the passageway of the submarine up to the stern. He's never seen again. [[ItAmusedMe Ward decided to just confuse the audience for a laugh]].

** A brief clip of R.J. boarding the ''Stingray'', high-fiving the rest of the crew as he goes. Spots also had Stepanak's "What's our mission, rescue Gilligan?" at first.

* UnintentionalPeriodPiece: Mostly averted, aside from the scene where the ''Orlando'' crewman [[https://www.youtube.com/watch?v=cveFKerkadA buys some gum]], which has 1996-era products visible, such as the now-discontinued Butterfinger BBs.
* WhatCouldHaveBeen: Tom Arnold was offered the leading role at first, but turned it down for another project (most likely, and ironically, ''Film/McHalesNavy''). He later said that he felt that Kelsey was the better choice.

* GeniusBonus: During the final chase, Howard yells into the squawk box, "This is what I ''live'' for! ''DBF!!"'' DBF is short for "Diesel Boats Forever!", and was the unofficial motto of the US Navy's long-since-retired diesel submarine fleet as nuclear-powered subs became more common. Howard is relishing the chance to best a modern nuclear boat with his venerable diesel sub. Also a bit of ActorAllusion, as Creator/HarryDeanStanton was a US Navy submariner in WWII.

** Early on in the film, the Admiral running the war games asserts that he wants "the sort of man with 'welcome aboard' tattooed on his"... gangplank. Try to picture any other Grammer role replying, with only mild sheepishness, that the Admiral does in fact happen to be talking to just such a man.

* {{Defictionalization}}: From 2004 to 2007, the US Navy actually conducted training exercises where they were up against a single diesel submarine. Granted that the sub they trained against wasn't a [=WW2=] derelict (the Swedish Navy's [[CoolShip Gotland]] is rather state of the art), the idea itself was the same, fighting against a single sub that was much harder to detect due to it's non nuclear nature.

* GeniusBonus: During the final chase, Howard yells into the squawk box, "This is what I ''live'' for! ''DBF''!!" DBF is short for "Diesel Boats Forever!", and was the unofficial motto of the US Navy's long-since-retired diesel submarine fleet as nuclear-powered subs became more common. Howard is relishing the chance to best a modern nuclear boat with his venerable diesel sub. Also a bit of ActorAllusion, as Creator/HarryDeanStanton was a US Navy submariner in WWII.

* WhatCouldHaveBeen: Tom Arnold was offered the leading role at first, but turned it down for another project (most likely, and ironically, ''Film/McHalesNavy''. He later said that he felt that Kelsey was the better choice.

* WhatCouldHaveBeen: Tom Arnold was offered the leading role at first, but turned it down for another project. He later said that he felt that Kelsey was the better choice.

* {{Defictionalization}}: From 2004 to 2007, the US Navy actually conducted training exercises where they were up against a single diesel submarine. Granted that the sub they trained against wasn't a WW2 derelict (the Swedish Navy's [[CoolShip Gotland]] is rather state of the art), the idea itself was the same, fighting against a single sub that was much harder to detect due to it's non nuclear nature.

* HeyItsThatGuy:
** Creator/PattonOswalt, before he became famous, plays a nameless crew member who operates radio (when it's not Nitro) of the Stingray who's visible throughout. He has all of one line in the entire film.
** Yet another CoolOldGuy role by Creator/HarryDeanStanton.
** Spots (Johnathan Penner) would later go on to appear in several seasons of ''Series/{{Survivor}}''.
** One of the two ''Orlando'' crewmen (the one who drops the quarter and two dimes) was also playing the chief engineer of ''Series/SeaQuestDSV'' at the time the film was released.
** [[Film/DumbAndDumber Mary Swanson]] is LT Emily Lake.

* PlayingAgainstType: KelseyGrammer as Lieutenant Commander Dodge. Many of Grammer's roles tend to be straight-laced intellectuals. Dodge, by comparison, is a MilitaryMaverick who takes to the whole "think like a pirate" thing like a duck to water.
* TruthInTelevision: The base premise - regarding diesel subs and war games - has played out multiple times, with the conclusions bearing out how much damage a particularly clever commander could do with a diesel sub. Interestingly, another major plot point also was shown to be true - at least one such war game was restarted after brass changed the rules partway through.
** There is also a real life program to allow women to serve in US Submarines, although this is restricted only to 'Ohio' class subs, which due to their size allows for dual sex dormitories.
** Continuing from the OfficeGolf on the main page. Life aboard '''ANY''' Warship is ''boring'', and many sailors search for ways to relieve the boredom. One such way to do that is golfing. This is especially true for officers who can be allotted extra personal space, and thus, allowed to bring additional items not normally allowed for the rest of the crew. Other items crew members have been known to bring include board games, game consoles, even laptop computers.

* HeyItsThatGuy: PattonOswalt, before he became famous, plays a nameless crew member of the Stingray who's visible throughout. He has all of one line in the entire film.