* AbilityOverAppearance: Several of the main actors top 6 feet (183 cm) (Creator/DennisQuaid and Scott Glenn in particular). However, none of the actual astronauts were over 5'11" (180 cm), as that was the maximum height allowed by the cramped ''Mercury'' capsu--er, [[InsistentTerminology spacecraft]]. Gus Grissom, who was 5'5" (165 cm) in real life, was portrayed by the 5'10" (178 cm) Creator/FredWard. The 5'10" Wally Schirra was, however, portrayed by the 5'10" Creator/LanceHenriksen.
* AcclaimedFlop: Despite being critically acclaimed and having been nominated for eight UsefulNotes/{{Academy Award}}s, the film failed to make back its budget.
* ActingForTwo: Levon Helm plays Jack Ridley and provides the off-screen narration.
* ActorSharedBackground:
** Like Gus Grissom, the late Creator/FredWard served in the U.S. Air Force.
** Creator/LanceHenriksen and his character Walter Schirra served in the U.S. Navy.
** Creator/ScottGlenn served in the Marines, technically part of the Department of the Navy, here playing Naval aviator Alan Shepard.
* BoxOfficeBomb: Budget, estimated between $19 million to $27 million. Box office, $21,192,102. The triple-hit knockout of this film, ''WesternAnimation/TwiceUponATime'', and ''Film/OnceUponATimeInAmerica'' (the third of which became the unfortunate victim of ExecutiveMeddling) led to the film's executive producer Alan Ladd, Jr. to shut down his production company and leave Warner Bros., and while he was appointed executive of MGM/UA just a year after the third aforementioned film's release, he would not return to his own and produce another film until ''Film/{{Braveheart}}''.
* CaliforniaDoubling: Averted. Location managers are not likely to find a place more desolate than Edwards AFB, although the "Australia" in the film looked a ''lot'' like some of the more desolate places on the base...
* CastTheRunnerUp: Creator/ScottGlenn was initially considered for the role of Chuck Yeager, but he expressed that he would rather play Alan Shepard, and was cast in that part instead.
* ChannelHop: The film was originally picked up by Creator/UnitedArtists, who outbid Creator/UniversalPictures for the rights to the book. They eventually put the film in turnaround and it was picked up by The Ladd Company.
* CreatorKiller: Along with ''WesternAnimation/TwiceUponATime'' and ''Film/OnceUponATimeInAmerica'', this film's high-profile box office failure was credited for bringing down the company of famed Hollywood executive Alan Ladd, Jr.
* DawsonCasting: A few of the principals were played by actors older than their characters.[[note]]For the Mercury Seven, we'll use their ages at selection in January 1959.[[/note]]
** Chuck Yeager was 24 when he broke the sound barrier. Sam Shepard was 40. Though the NF-104 accident at the end of the film did happen when Yeager was 40 in 1963.
** Alan Shepard was 36 when selected for the Mercury Seven. Scott Glenn was 44.
** Gus Grissom was 32 when selected. Fred Ward was 41.
** Wally Schirra was also 36. Lance Henriksen was 43.
* DisownedAdaptation: Creator/TomWolfe was unhappy with the film, because he felt it made too many changes to the book.
* ExecutiveMeddling: The military insisted that swearing be removed from the movie so that it would get a lower rating, becuase they wanted teens to watch it and join the army.
* FatalMethodActing: The stuntman portraying Chuck Yeager's bailout of the crashing F-104. His helmet filled with smoke, and he didn't get his parachute deployed. Yeager himself -- a technical adviser for the film as well as giving his cameo -- not only refused to re-enact the flight (he did most of the flying filmed), he had warned against stunt personnel doing so, warning that it would almost certainly be a fatal mistake. The scene is also a strange bit of TruthInTelevision, as Yeager actually collided with his seat after ejecting, and his helmet filled with liquid explosive materials, similarly filling his helmet with smoke and burning his face to a cinder. The aftermath is portrayed in the OutOfTheInferno shot listed on the main page.
* IronyAsSheIsCast: Creator/SamShepard, who played legendary pilot Chuck Yeager, was actually afraid of flying.
* NoDubForYou: The film was released in Japan in 1984. However, it wasn't until 29 years later that the film would eventually receive a dub.
* NoisyNature: The NASA recruiters'[[note]]Jeff Goldblum and Harry Shearer[[/note]] arrival at Edwards AFB is punctuated by the distinctive song of a [[https://www.allaboutbirds.org/guide/Canyon_Wren canyon wren]], which to be fair is location-accurate.
* RealitySubtext:
** Towards the end of the movie, Alan Shepard tells his wife Louise, in a "one of these days..." manner, "I'm going to the moon...". Shepard would be the only one of the Mercury Seven who would go to the moon, on Apollo 14 [[note]]He was slated to be on the first Gemini mission, but got grounded due to an inner ear condition. After the docs cleared him, Shepard was initially assigned to Apollo 13, NASA execs moved him to Apollo 14 to give his crew more time to train[[/note]].
** During the astronaut tryouts in the movie, Gordon Cooper gloats about breaking the record for holding one's breath, only to realize that John Glenn and Scott Carpenter are still going after he's done. In real life, Cooper did hold his breath the longest, since he was the only non-smoker in the Mercury Seven.
** At the movie's end, before Cooper lifts off on his mission, he's shown dozing off. Cooper was the first astronaut to sleep in outer space.
** The real John Glenn tried to use this for a presidential run in 1984. He didn't make it out of the Democratic primaries, finishing sixth with only two delegates while his campaign was saddled with over $3 million in debt.
* ReferencedBy: Apart from the countless power-walk scenes that have been inspired by this movie, the ''Series/{{Community}}'' episode "Basic Rocket Science" borrows wholesale from it. (For example, it opens with a parody of the EverybodyKnewAlready scenes on the main page.)
* UnderageCasting: Dennis Quaid was 28 playing 33-year-old Gordo Cooper, while Ed Harris was 33 playing 37-year-old John Glenn.
* WhatCouldHaveBeen:
** Creator/WilliamGoldman was originally hired to write the script. This version focused on the astronauts, entirely ignoring Chuck Yeager.
** Music/JohnBarry was the original composer, but left because he found it impossible to understand what Philip Kaufman wanted from the score, citing a meeting where Kaufman described his ideal score as "sounding like you're walking in the desert and you see a cactus, and you put your foot on it, but it just starts growing up through your foot." In the end, Music/BillConti wrote the music.
** Creator/JohnAvildsen and Creator/MichaelRitchie were considered to direct.
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