The World War I Flying Ace is one of the many fantasy identities that Snoopy adopted during the fifty year run of the Peanuts comic strip. In the early years of the strip, Snoopy would pretend to be other animals, such as a vulture, a boa constrictor or a piranha. As his character developed, Snoopy's imaginary life became more complicated. Many strips would focus on Snoopy pretending to be a lawyer or the student "Joe Cool." However, the World War I Flying Ace would be one of Snoopy's most popular and enduring alternate identities.
Snoopy's first appearance as the World War I Flying Ace was in the Peanuts comic strip from October 10, 1965, which saw him climb on top of his doghouse (claiming it was a Sopwith Camel biplane) to do battle with the Red Baron. The fantasy ended when Linus came up behind him and imitated the noise of a machine gun.
Often, when Snoopy is seen as the World War I Flying Ace, it is hard for other characters to get his attention, because all Snoopy cares about at that point, is his imaginary battles. For instance, in the strip from June 20, 1989, when Charlie Brown comes home from camp, and really misses Snoopy, the first thing Snoopy (as the World War I Flying Ace) says when he sees the boy is, "Don't they realize how dangerous it is to let unauthorized kids on the runway?".
Often, after an imaginary battle, Snoopy will call out "Curse you, Red Baron!"
The first television appearance of Snoopy as the World War I Flying Ace was in the animated special, It's the Great Pumpkin, Charlie Brown, initially broadcast on October 27, 1966. In the special, Schroeder appears to be happy to go along with Snoopy's game by playing popular songs from the World War I era on his toy piano.
Other characters would participate in Snoopy's imaginary World War I exploits during the strip's run, including his friend Woodstock and his siblings, Belle and Spike. The most eager human participant appears to be Marcie, who is happy to accept the role of "French lass" who falls for the dashing pilot. However, Snoopy's brother Marbles refused to take part in the game and found his brother's behavior very confusing.
U.S. miltary usage
Various cartoon characters from outlets such as Warner Brothers and Disney have been used as mascots of US military units. Aware of the legal battle between The Royal Guardsmen and United Features Syndicate, over the band's unauthorized use of the name "Snoopy" in their song "Snoopy Vs. The Red Baron", a fighter squadron in the Vietnam War that wanted to use Snoopy the World War I Flying Ace as their mascot wrote to Charles M. Schulz to ask permission first. Schulz, a veteran himself, approved Snoopy in Red Baron-hunting mode as the squadron's mascot.