FREE FALLING: Skydiver Aims to Smash Record, Sound Barrier in 23-Mile Jump. “As he plummets 23 miles in the highest skydive ever, Baumgartner will become the first person to break the sound barrier in free fall. That’s the plan, anyway. To even attempt this will expose him to many challenges, including the risk that water in his body could vaporize. But one challenge in particular is foremost in everyone’s mind: What happens when Baumgartner encounters the shock waves that invariably occur when something exceeds the speed of sound? No one really knows.”