The cast and crew flew between 500 and 600 parabolic arcs in NASA's KC-135 airplane (nicknamed the "Vomit Comet") to achieve real weightlessness. Each of the arcs got them 23 seconds of zero gravity. All of these flights were completed in 13 days. The actual KC135 used (NASA serial number N930NA) was decommissioned in 2000 after 27 years of service and is on display at Ellington Field.
The line that Jim Lovell asks his crewmates, "Gentlemen, what are your intentions? Mine are to go home." needs some context. While Lovell actually said this, it seems slightly forced and out of place. This is because when he said it on the mission, they were just coming out of from the far side of the moon and had a critical engine burn coming up. Since it was Swigert and Haise's first mission, they were taking pictures instead of preparing for the burn. That's why Lovell said the line, adding, "If we don't get home, you won't be able to have your pictures developed."
Jim Lovell wore his old navy captain's uniform in the scene where he greets the astronauts aboard the Iwo Jima. When Ron Howard asked Lovell if he'd like to be in the film as the ship's admiral, Lovell agreed but pointed out, "I retired as a captain; a captain I will be."
Several items in the movie, including Jim Lovell's jumpsuit and a coffee mug at Mission Control bear the mission patch for Apollo 8, the mission that took Lovell to the moon for ten orbits a year and a half earlier.
The movie makes no mention of a mid-course correction made while en route to the moon which took the spacecraft off of a free return trajectory. After the explosion, a second correction was successfully made to put the spacecraft back on a free return trajectory. Without this correction, the astronauts still would have swung around the moon, but would have missed the earth on the return leg. Although a free return trajectory was agreed upon in the movie, the engine burn to accomplish this was not portrayed. The astronauts also made a four-minute engine burn after swinging around the moon to gain additional speed and to enable them to splash down in the Pacific Ocean. There is a brief reference to this in the movie, but this maneuver was not portrayed.
Jim Lovell's line "I vonder vere Guenter vent" was made popular by the crew of Apollo 7. Guenter Wendt was NASA's "pad leader" during the Apollo program and was the last man seen by crews before liftoff. After Wendt closed Apollo 7's hatch and his face disappeared from the window, CSM pilot Donn Eisele said, "I wonder where Guenter went." Commander Wally Schirra claims to have stolen the line and made it famous among astronaut crews.
Several actors from the movie including: Tom Hanks, Bill Paxton, Kevin Bacon, and Gary Sinise visited US Space and Rocket Center Space Camp program and worked on their simulators before production of the movie began to help them get a feel for what it would be like to work in zero gravity.
St. John's Military Academy, the school that Jim Lovell's son attends during the mission, is a real military school located in Delafield, Wisconsin. The scenes in the movie showing the school were not, however, filmed on location.
The scene of the Saturn V launch shows the horizontal service arms swinging back after the rocket's ignition. The arms swung back in milliseconds after ignition, once the rocket climbed to a height of two inches. In the movie the service-arms goes in one by one, but in reality they went simultaneously.
The Time Magazine 'Men of The Year' cover that Haise (Bill Paxton) and Kenneth Mattingly (Gary Sinise) look at during the Apollo 11 party at the Jim Lovell's house is a real magazine cover, famously celebrating the Apollo 8 missions orbiting of the moon. However, it has been edited, replacing the original caricature of Lovell, with one of Tom Hanks for movie consistency. Borman and Anders remain unchanged given that they don't appear in the film.
The Navy SH-3H Sea-King "66" helicopter from the rescue scene is not the original rescue aircraft from the Apollo missions as previously stated, as the original "66" had been lost at sea before the film was made. Another Sea King (bureau number 148999) was painted up like the original and used for filming. This helicopter can (as of Dec. 2008) be seen on display at the USS Hornet Museum in Alameda, CA. The aircraft was assigned to and flown by crews from HC-85, a Naval Reserve squadron based at NAS North Island in San Diego, CA. HC-85 was one of the last units to fly the Sea King helicopter in the U.S. Navy.
Gene Kranz (Ed Harris) gives a list of instructions to his team at Mission Control and finishes by saying, "Failure is not an option!" Gene Kranz did not actually say this during the Apollo 13 mission, but he liked the line. He would later use it as the title of his 2000 autobiography.
The scene where the engineers are challenged to create a device to use the square CO2 absorbers using only items on board was the inspiration for Cathy Rogers to create the TV shows Junkyard Wars (1998) and Junkyard Wars (2001).
According to Ed Harris, Gene Kranz's reaction to the astronauts living, which was sitting in a chair, almost overcome with emotion, was inspired by a documentary interview of Gene, who, while describing his feelings as the astronauts made it back, started to break down.
All the screens in the fictional Houston control room were monitored by a software center that was built just below the set. According to director Ron Howard, almost three days of production were lost while trying to fix the software, which wouldn't work properly.
In interviews, the real Jim Lovell had said that he thought Kevin Costner looked a little bit like him, but Costner was never cast. When Brian Grazer and Imagine Entertainment got the rights to the script, Ron Howard signed on to direct and knowing that Tom Hanks was an Apollo/space buff, sent the script to him. They set a meeting and Hanks agreed to play Jim Lovell during Hanks' and Howard's first meeting about the film.
The famous understatement was actually made twice by two astronauts. Jack Swigert said, "OK Houston, we've had a problem here." Mission Control said, "This is Houston. Say again, please." Then Jim Lovell said, "Ahh, Houston, we've had a problem." On the recording, Swigert is garbled at the beginning, while Lovell is clear, so the recording of Lovell is often heard, leading to the impression he said it, even though Swigert said it first. It's commonly misquoted as, "Houston, we've got a problem," or "Houston, we have a problem." Because "we've had" implies the problem has passed, Ron Howard chose to use "we have".
According to his book "Lost Moon". Jim Lovell really did make the suggestion to his wife of going to the moon instead of Acapulco, but it was when he got the word that he would be going to the moon on Apollo 8 in December 1968.
Bill Paxton's line, "I could eat the ass out of a dead rhinoceros." was not said by Fred Haise. It was made up the day of filming by Gary Busey, who was visiting the set at the time and they thought it would be a good country boy line. Busey had previously said the line in another film he starred in, Point Break (1991).
Over the course of lunch with his idol Billy Wilder, Ron Howard has said that he was thrilled to learn that Wilder deemed this movie to be Howard's best work as a director because it was about a guy who did NOT realize his dream, and that's what made it so remarkable.
At one point during the return flight there is a bang and nobody is very alarmed; it's just a "burst helium disk." This was actually a significant event, though an expected consequence of the situation. The helium disk served a protective function in the LM descent engine and, after it burst, they might no longer be able to restart that engine. A final course correction, not shown in the movie, had to be done using thrusters instead.