02/06/2012 11:24 am ET Updated Dec 06, 2017

Felix Baumgartner's Skydive To Break Sound Barrier Wouldn't Be First High-Altitude Plunge (PHOTOS)

Daredevil Felix Baumgartner is planning to skydive from 23 miles up and break the sound barrier during the freefall down toward Earth. It may sound unprecedented, but the Red Bull-sponsored stunt is an homage to another famous jump, known as Project Excelsior, all the more impressive because it was completed in 1960.

U.S. Air Force Colonel (then Captain) Joe Kittinger had a fascinating career, but the highlight may have been that 102,800-foot jump, seen in the slideshow below. (All photos via U.S. Air Force. Story continues below.)

Historic Parachuter

Kittinger's jump tested the limits of human freefall like never before. He was almost killed in a test jump when he blacked out after an equipment malfunction caused him to go into a spin at 120 revolutions per minute.

One risk Kittinger faced was only discovered after Project Excelsior was completed: according to weather balloon information database Stratocat, "During the ascent, the pilot began experiencing severe pain in his right hand caused by a failure in his pressure glove. Apparently the glove failed due to a crack in the oxygen line. This would have been enough to abort the mission, but Kittinger did not initially report the problem because he did not want to terminate the test."

Kittinger's flight aided research at the cutting edge of military technology. It took place near the edge of Earth's atmosphere and undoubtedly faced the edge of human experience. As Kittinger told Vice magazine, "It was just amazing to look up and see the black sky. It's really a shocking event to behold."

Following in Kittinger's footsteps, Baumgartner's team will announce the date for his jump this week, according to the Telegraph. The jump will likely take place in August, in the skies over New Mexico, where Baumgartner will ride a 400-foot-wide weather balloon for three hours to reach his record-setting altitude.

Besides breaking Kittinger's altitude record and breaking the sound barrier with nothing but gravity propelling him, he hopes to achieve two other world records: the longest distance travelled in a skydive and the highest manned flight in a balloon.