Scream, Wilhelm! Scream!

Wiki:

The Wilhelm scream is a frequently-used film and television stock sound effect first used in 1951 for the film Distant Drums. The effect gained new popularity (its use often becoming an in-joke) after it was used in Star Wars and many other blockbuster films as well as television programs and video games. The scream is often used when someone is either pierced with an arrow, or falling to their death from a great height or because of an explosion.

The Wilhelm scream has become a well-known cinematic sound cliché, and is claimed to have been used in over 216 films.

The sound is named for Private Wilhelm, a character in The Charge at Feather River, a 1953 western in which the character is shot with an arrow. This was believed to be the second movie to use the sound effect and its first use from the Warner Brothers stock sound library.

The sound effect originates from a series of sound effects recorded for the 1951 film Distant Drums. In a scene from the film, soldiers are wading through a swamp in the Everglades and one of them is bitten and dragged underwater by an alligator. The scream for that scene was recorded later in a single take along with five other short pained screams, which were slated as "man getting bit by an alligator, and he screams." The fifth scream was used for the soldier in the alligator scene—but the 4th, 5th, and 6th screams recorded in the session were also used earlier in the film—when three Indians are shot during a raid on a fort. Although takes 4 through 6 are the most recognizable, all of the screams are referred to as "Symon" by those in the sound community.

The Wilhelm scream's revival came from motion picture sound designer Ben Burtt, who re-discovered the original recording (which he found as a studio reel labeled "Man being eaten by alligator") and incorporated it into a scene in Star Wars Episode IV: A New Hope. Aboard the Death Star, just before Luke Skywalker and Leia swing across a chasm, Luke shoots a Stormtrooper who screams as he falls down the chasm. Burtt is credited with naming the scream after Private Wilhelm (see The Charge at Feather River). Over the next decade, Burtt incorporating the effect in other films he worked on, including most projects involving George Lucas and/or Steven Spielberg (it is used in all of the Indiana Jones movies). Other sound designers picked up on the effect, and inclusion of the sound in films became a tradition among the community of sound designers. It has also been used in several games and television series.

Research by Burtt suggests that actor and singer Sheb Wooley, best known for his novelty song "Flying Purple People Eater" in 1958, is likely to have been the voice actor who originally performed the scream. This has been supported by a 2005 interview with Linda Dotson, Wooley's widow. Burtt discovered records at Warner Brothers from the editor of Distant Drums including a short list of names of actors scheduled to record lines of dialogue for miscellaneous roles in the movie. Wooley played the uncredited role of Private Jessup in Distant Drums, and was one of the few actors assembled for the recording of additional vocal elements for the film. Wooley performed additional vocal elements, including the screams for a man being bitten by an alligator. Dotson confirmed that it was Wooley's scream that had been in so many westerns adding "He always used to joke about how he was so great about screaming and dying in films."