Now, this might sound like something out of a superhero movie, but no, humans can't break the sound barrier unaided. Chuck Yeager first shattered the sound barrier flying an X-1 aircraft in 1947. However, in freefall, people can reach astonishing speeds. Felix Baumgartner came close during his stratospheric jump in 2012, reaching speeds of up to 843.6 mph, but that's still under the sound barrier.