The Sky Crawlers is a 2008 anime movie, based off a book within a series of novels by Hiroshi Mori. It's a war movie, although in this case it's set in an alternate history, and the "war" is between two martial corporations. It's the story of a group of fighter pilots.
Although the world is (seemingly) at peace, the argument goes that people are unused to a world without wartime aggression and casualties, so corporations contract soldiers and fighter pilots to engage in real battle with one another to provide the necessary headlines. The companies have specific people who do this: the "Kildren," a group of genetically engineered young adults who neither age nor die--at least not of natural causes. Because they only die if killed, like in battle, it's the perfect solution to the companies' need to fill their pilots and tanks.
The main character of The Sky Crawlers is Yūichi Kannami, an ace pilot of the Rostock Corporation who transfers to a small rural base at the start of the movie. He works with three other pilots, and with Suito Kusanagi, the girl in charge of the base, who also flies when a pilot is injured/killed or when a plane is damaged. All the pilots and the commander are Kildren; the only people on the base who are not are the mechanics. In fact, there is only one pilot in the whole war who is an adult: The Teacher, a former Rostock pilot who joined its rivals. He is the main enemy of the Kannami and his fellow pilots, the one no one else has been able to beat. While the wider story involves plans of a siege attack on the rival corporation and the discovery of secrets surrounding the Kildren, it's really the battles with the Teacher that absorb Kannami, and all the pilots', attention. For a movie full of aerial dogfights, it's surprisingly slow.
An interesting aspect of the film is that all the characters typically speak Japanese in their daily lives; but when they're in the cockpit of their planes and flying, they speak in English. It raises some neat questions about the training the Rostock Corp. provides.
The film was produced by I.G. Production and the soundtrack was done by Kenji Kawai, so it has a similar feel to the Ghost in the Shell series (which was done by the same people). It was distributed in the U.S. by Sony Pictures, without an English dub. There is also a game for the Wii, Sky Crawlers: Innocent Aces, which has been translated into English; and a manga and the aforementioned novel series, which have not.