In “Speed” (1994) - the iconic  scene where the transit bus jumps over a 50-foot chasm on an unfinished Los Angeles freeway is one of the most famous practical stunts in movie history.  While the physics of the jump are impossible - the stunt itself is real.  The crew used a real bus launched at high speed off a custom-built, 100-foot-long and 8-foot-high ramp with a 16-foot kicker on an unused section of Los Angeles freeway.  A professional stunt driver piloted from the middle of the vehicle, wearing a special shock-absorbing bungee harness system to prevent severe spinal injury upon landing.  The roadway underneath the jump wasn't actually missing - the 50-foot chasm was digitally inserted in post-production using matte paintings, scaffolding removal, and digital composite work.
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