IMDB trivia:
This film is used by the U.S. Navy as an example of leadership styles in its Leadership and Management Training School. The Air Force's College for Enlisted Professional Military Education also uses this film as a education aid in its Noncommissioned Officer Academies.
John Wayne turned down the leading role that later went to Gregory Peck.
The B-17 bomber crash landing at the airstrip near the beginning of the movie was no special effect. Stunt pilot Paul Mantz was paid $4,500 to crash-land the bomber. Mantz of course walked away from the wreck. Until the 1970s, that was the largest amount ever paid to a stuntman for a single stunt.
This film is frequently cited by surviving bomber crewmembers as the only accurate depiction from Hollywood of their life during the war.
A replica of the 918th Bomb Group's Robin Hood toby mug is in use by the Officer's club at Whiteman AFB, Missouri, home of the 509th Bomber Wing. The real movie prop mug, which was the prized possession of the Frank Armstrong family, fell victim to theft in the early 90s and has not been seen since. The replica mugs are still in production and available from 918thpx.com.
One of the first Hollywood films to deal with the psychological effect of war on its soldiers.
The air battles were cut together from authentic World War II footage.
http://www.imdb.com/title/tt0041996/trivia
IMDB forum, with feedback that you might find interesting and helpful:
http://www.imdb.com/title/tt0041996/board/nest/24006830
The responses to the person who started the thread are from people who obviously know what they are writing about.
Wikipedia information:
"Twelve O'Clock High" was produced with the full cooperation of the United States Air Force and made use of actual combat footage during the battle scenes. A good deal of the production was filmed at a working air base, Eglin Air Force Base Screenwriters Bartlett and Lay drew on their own wartime experiences with Eighth Air Force bomber units. Veterans of the heavy bomber campaign frequently cite "Twelve O'Clock High" as the only Hollywood film that accurately captured their combat experiences.
Along with the 1948 film Command Decision, it marked a turning away from the optimistic, morale-boosting style of wartime films and toward a gritty realism that dealt directly with the human costs of war. Both films deal with the theme of "daylight precision bombing" without the need for fighter escort, the basic Army Air Force doctrine at the start of the Second World War. In retrospect, this was a strategic mistake. Daylight precision bombing became a viable technique only after long-range fighters were developed (notably the P-51 Mustang) capable of escorting bombers all the way to the target and back.
Savage is modeled on Colonel Frank A. Armstrong, Pritchard on General Ira Eaker, the fictional 918th Bomb Group on the actual 306th Bomb Group. The film's most significant deviation from history comes in its climax: Savage's psychological breakdown was not based on any real-life event but was intended to portray the effects of intense stress experienced by many airmen.
This film is widely used in both the military and civilian worlds to teach the principles of leadership. It is required viewing at all the American service academies. It has also been deemed "culturally significant" by the United States Library of Congress and selected for preservation in the National Film Registry.
Wikipedia also has background on the people on whom characters are based.
http://en.wikipedia.org/wiki/Twelve_O'Clock_High