To Fly! is a 1976 American short docudrama film directed by Greg MacGillivray and Jim Freeman of MacGillivray Freeman Films, who wrote the story with Francis Thompson, Robert M. Young, and Arthur Zegart. It premiered at the giant-screen IMAX theater of the National Air and Space Museum, which opened to celebrate the United States Bicentennial. The film chronicles the history of aviation in the US, with a narration written by Thomas McGrath. Thematically, it explores the search for national identity through the country's westward expansion as well as humanity's relationship with aviation.

The idea of the film was proposed in 1970 and revisited two years later following the museum's interest in an IMAX theater for the planned building. MacGillivray and Freeman expanded a treatment written by the Smithsonian Institution and Thompson, adding various scenes in the storyboard intended to jolt IMAX audiences. Due to the large dimensions of the screens, the filmmakers aimed for immersion and clarity via novel cinematographic techniques. This was further enhanced by the surround sound design. The ending space sequence, featuring the first IMAX rocket launch scene, was made with various experimental special effects. The film was edited by MacGillivray and Freeman, and features a score composed by Bernardo Segall. It was finished on schedule in two years, with a low US$590,000 fund from Conoco.

To Fly! was released on July 1, 1976, distributed by Lawrence Associates and Conoco. It was initially scheduled to screen only for the Bicentennial, but due to public demand was kept indefinitely. In response to these demands, a 20th-anniversary special edition was released in 1996. The film led to an increase in the number of IMAX theaters worldwide and helped popularizing the nascent format, with various intense reactions observed among audiences, and was thus included in the National Film Registry and IMAX Hall of Fame. It also set MacGillivray as a major IMAX filmmaker. With increasing popularity, To Fly! remained among the highest-grossing giant-screen documentaries. Critics praised the film in its audiovisual and narrative aspects—though some were negative on the latter—and it received several accolades.