Sonny Landham -- who played Billy the self-knifing military badass in "Predator" -- has passed away in a Kentucky hospital at the age of 76 from congestive heart failure.
Landham was part of Arnold Schwarzenegger's band of special forces soldiers in the 1987 flick -- and starred in the famous scene where he tried to go one-on-one with the alien armed only with a knife.
He lost ... but he went down in a frickin' blaze of glory.
Landham also appeared in "48 Hours" -- in which he also played a guy named Billy.
Before going mainstream, Landham starred in a bunch of low-grade porn flicks -- including "Slippery When Wet" -- but regretted it and said he needed the money at the time.
He later got into politics -- running for several offices in Kentucky, but never got elected.