His friend of more than 40 years and former co-star on NBC's "Buck Rogers in the 25th Century," Gil Gerard announced the news on Twitter.
"Felix died just a few hours ago and the only good I can draw from his passing is that he didn’t suffer any longer," he wrote. "I will miss him terribly, especially the great time we had at our panels. Just him telling me to, 'go 'f' myself.'"
He also appeared in "Buck Rogers" as Twiki the robot sidekick, a hang-gliding Ewok in the 1983 "Star Wars: Episode VI -- Return of the Jedi," and the villain Livak opposite George Segal in the 1975 film -- and sequel to "The Maltese Falcon" -- "The Black Bird."
Silla was born on Jan. 11, 1937 in Roccacasale, Italy and came to the United States in 1955 when he began to tour with Ringling Bros. and Barnum & Bailey Circus, working as a trapeze artist, tumbler and bareback horse rider, according to The Hollywood Reporter.
TMZ reported Friday that he landed in Hollywood in 1962 as a stuntman, appearing first in "A Ticklish Affair," an episode of the classic television show "Bonanza," and the first pilot for "Star Trek: The Original Series."
In addition, The Hollywood Reporter noted Silla's work in "Point Blank," "The Kentucky Fried Movie," "The Brood" and "Spaceballs" with Mel Brooks and Rick Moranis.
He was known as a regular performer for Sid and Marty Krofft on the wacky "H.R. Pufnstuf and Lidsville," Deadline said Friday.
Later on in his career, Silla had small roles in the 1968 science-fiction classic "Planet of the Apes," "Demon Seed," and 1984 favorite "Indiana Jones and the Temple of Doom."
IMDb.com cited his stunt work on "The Towering Inferno," "The Hindenburg," "ET the Extra-Terrestrial," "Poltergeist", "Howard the Duck" and "Batman Returns."
Silla moved to Las Vegas in 2003 and played the harmonica with his own original combo, the Hollywood Reporter said.
He was also a regular at fan conventions.
Silla is survived by his wife of more than 55 years, Sue, and their children, Bonnie and Diana. Their son Michael, 45, passed away in March 2020.