Supersonic Freefall: What Felix Baumgartner’s 37-km Jump Will be Like

Sometime this summer, Austrian skydiver Felix Baumgartner will leap from the edge of space, attempting to not only break the sound barrier with his body, but also break the record for the longest freefall. As no one has successfully jumped from this height before, it’s uncertain what the highest supersonic freefall in history will look or feel like. This animated video put out by the Red Bull Stratos team provides a sense of what to expect during the attempt.

“After years of training with my team of dedicated Red Bull Stratos experts, I’ll be going on a journey that no one has ever done,” Baumgartner told Universe Today in 2010 in an email message. “If I succeed, I will be the first person to break the sound barrier, alone. That will be a record for all eternity. As such, a piece of me will become immortal. That excites me.”

42-year-old Baumgartner is hoping to jump from nearly 37 km (23 miles, 120,000 feet) to break the current jump record held by Joe Kittinger a retired Air Force officer, who jumped from 31,500 meters (31.5 km, 19.5 miles, 102,000 ft) in 1960. Now 83, Kittinger is assisting Baumgartner in preparations for the jump.

There have been several attempts to surpass Kittinger’s record, but none have succeeded, and people have given their lives for the quest. Kittinger’s jump contributed valuable data that provided ground work for spacesuit technology and knowledge about human physiology for the US space program.

Image caption: Felix Baumgartner and life support engineer Mike Todd celebrate after landing of the first manned test flight for the Red Bull Stratos in Roswell, New Mexico on March 15, 2012. Credit: Red Bull Stratos.

If Baumgartner is successful, the Red Bull Stratos mission will break four world records: the altitude record for freefall, the distance record for longest freefall, the speed record for fastest freefall by breaking the speed of sound with the human body, and the altitude record for the highest manned balloon flight.

How fast will Baumgarter need to go to beat the speed of sound? Sound travels at different speeds through the atmosphere (as well as through different mediums), depending on atmospheric density and temperature. For example, at sea level, in average conditions of about 15 degrees C (59 degrees F), sound travels at around 1,223 kph (760 mph). But at higher altitudes, where the air is colder, sound travels more slowly.

Researchers with the Red Bull Stratos mission anticipate Baumgartner could break the sound barrier at about 30,480 meters (100,000 feet) above sea level, in temperatures of -23 to -40 C (-10 to -40 F) where sound travels at about 1,110 kph (690 mph) or roughly 304 meters per second (1,000 feet per second).

So, he’ll have to go faster than those speeds – or Mach 1 — to be supersonic.

While there is no literal “barrier,” the transition to supersonic speeds can cause problems for aircraft as transonic air movement creates disruptive shock waves and turbulence. Data obtained from Chuck Yeager’s first supersonic flight in 1947 allowed for changes in design of supersonic aircraft to avoid problems. Still, some aircraft do experience problems at that point, and going supersonic has been attributed to some air disasters.

And the human body isn’t designed for supersonic speeds.

“Our biggest concern is that we don’t know how a human unencumbered by aircraft is going to transition through this,” said the project’s Medical Director Dr. Jonathan Clark, a flight surgeon for six space shuttle missions (and husband of astronaut Laurel Clark who died in the Columbia disaster in 2003), who has researched numerous aerospace disasters. “But it’s also exactly what we’re hoping to learn, for the benefit of future space flights.”

Documents provided by the Red Bull Stratos mission say that the data obtained from the mission will be shared with the scientific community, and Clark noted that he expects long-awaited medical protocols to be established as a result.

A live webcast of the Red Bull Stratos freefall will air on the Red Bull Stratos website.

21 Replies to “Supersonic Freefall: What Felix Baumgartner’s 37-km Jump Will be Like”

  1. I know Joe Kittinger. He only hopes for the best for this guy. Good luck, Felix!!

    1. Why not? In the dense lower atmosphere, drag will inevitably cause him to slow to the terminal velocity of any other skydiver…

  2. I think he should take anything that isn’t white or silver/Mylar like covering OFF his jump suit for the ascent to that altitude. HOT spots…… hmm. Or maybe they thought of that? and are using the darker emblems and logo’s for warmth?

    1. He’s efectively searing a space suit. Space suits I’ve seen are insulating to prevent heat escaping. Over heating during the ascent will likely be the bigger concern.

    1. Virtually none. Almost all of the heat that re-entering objects experience is from air being compressed in front of them, not from friction.

    1. Totally.

      Especially since he will sit most of the scary portions out going up and down, see above. Talk about facing your destiny the wrong way. =D

  3. I don’t get it – what’s the point? Very slick video presentation though; where’s the money coming from? Oh wait, by number of times Red Bull is mentioned I see a ‘documentary’ with Red Bull plastered all over it. Maybe on TDC.
    BTW: He ain’t gonna fall like that. Sorry, no sky surfing. Until he gets to much denser air the only possible stable posture is butt down, arms and legs extended, like a shuttlecock.

    1. Even if it documents what they want to happen, it isn’t posted here as such. But yes, it is a “pockumentary” (out of deep pockets).

      I doubt he will do much of an easy stand either, as he will be wearing a “pressure suit“. If memory serves, Kittinger had to constrain himself to just tip out of his chair because of the pressure suit action.

      Of course, Baumgartner may have a space suit version. This enables him to go into a diver position later if they have paid for full joint function of stretchable legs. But none of those record implies they have, “distance record” could (and maybe should) be vertical distance.

      1. Baumgartner’s suit (by the David Clark company IIRC) has good constant volume joints to allow excellent mobility while pressurized. I got a chance to examine one of his suits at the Space Tech Expo in May, and Tom Zackman (who used to work with me at XCOR) rather proudly showed off the details. It’s a small aerospace world.

    2. Beyond being a marketing stunt, one has to think of the potential for science here. This could lead to knowledge about what the human body can endure when freefalling from sub-orbital altitudes. That knowledge can then be used to work out what extra stresses would be encountered from Orbital or even extra orbital distances. If nothing else, that data could be used to design some type of emergency system (other than a “lifeboat”) should astronauts, in the worst case scenario, need to “jump” home after some sort of accident on an orbital platform. It’s obviously not the PREFERRED method, but hey, if it means we have one more way to get our men and women in space home alive, I say go for it! Good luck Felix!

    3. No, Rick, a delta or track position should work just fine, even at low dynamic pressure. The first ten to twenty seconds may have such low effective airspeed that he may do a front flip or two before he can use the relative wind to stop his angular momentum from the exit. In my skydiving days many many moons ago I occasionally went straight from the wing strut to a delta to accelerate quickly. In fact, a delta should help keep shock waves from his forearms from interacting with his helmet and causing uncommanded yaw.

  4. I’ve heard it described as “That’s one giant leap for man; one small step for mankind.”

    But predicted science is more than initially advertised, apparently.

  5. “And the human body isn’t designed for supersonic speeds.”

    let me fix that for you …

    “And the human body isn’t designed.”

    There, that’s better. 🙂

  6. 1. He will be nowhere near the edge of space. He has another 39miles to go for that.
    2. I was under the impression that he is likely to go into a tumble to begin with as there is so little air that he will effectively have no way to control is flight attitude.
    3. How cool would it be if he said ‘This is one small step for a man, one giant AAAAAaaaaaaaaa……..’ on his way off the capsule.

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