This story was updated at 9 p.m. ET.
A skydiver is making progress with plans to leap from near the edge of space in a dive that would break world records and the sound barrier.
Austrian daredevil Felix Baumgartner is a step closer to attempting the feat after a series of recent high-altitude test jumps. He plans to make his ambitious jump attempt later this year.
Starting in the stratosphere at 120,000 feet above the ground, Baumgartner will leap from a capsule suspended by a helium balloon near the boundary of space.
Sponsored by the energy drink company Red Bull, Baumgartner's mission ? called Red Bull Stratos ? seeks to extend the "safety zone" of human atmospheric bailout last set in 1960 by diver Joe Kittinger. This limit defines the uppermost altitude a human being can safely jump from.
"Right now, the space shuttle escape system is certified to 100,000 feet," said the mission's medical director Jonathan Clark, a former NASA flight surgeon. "Why is that? Because Joe Kittinger went there. You've got a lot of companies that are vying for the role of being the commercial space transport provider for tourism, for upper atmospheric science, and so on. These systems, particularly during the test and development phase, need a potential escape system, which we may be able to help them provide with the knowledge we gain." [Graphic: Earth's Atmosphere From Top to Bottom]
Taking the leap
A team of aeronautics experts recently led Baumgartner through a week of testing meant to illuminate any possible weaknesses in his equipment and to familiarize him with the skills needed to navigate the conditions expected to assail him as soon as he opens his vessel door.
Only a few feet above ground in a capsule dangling from a crane on Sage Cheshire Aerospace test grounds in California, Baumgartner practiced exiting and stepping off his hot-air balloon. Even a slight stumble during this step could cause dangerous alterations in his in-flight position only moments later, as well as reduce his chances of actually breaking the sound barrier.
"The team anticipated that the capsule would tip forward when Felix moved his approximately 270-pound self from the seated center position of the capsule to the step-off platform on the edge of the capsule," Red Bull Stratos Aerial Strategist and Skydiving Consultant Luke Aikins told SPACE.com. "What the exercise demonstrated was that the capsule moved only about a foot, which tells us that we don't have to worry about the capsule swinging back violently when Felix steps off."
Baumgartner proceeded to practice his step-off technique from higher up by doing bungee jumps while wearing a pressurized spacesuit and helmet. At 200 feet above ground in an abandoned fairground, the setting was a far cry from a high-altitude jump, but mimicked the sensation of trying to achieve the necessary forward rotation, said mission technical director Art Thompson. After a few leaps, one team member described Baumgartner's performance as "perfect."
"We still have an unknown, which is what happens to my body when I break the speed of sound, but at least we're going to know that I'm able to handle the step-off," Baumgartner said.
Lastly, the pilot passed several high altitude test dives at 26,000 feet over the desert in Perris, California. Thanks to a new chest pack aligned to one side of his body, Baumgartner exhibited a harmonious passage compared to previous trials a year earlier.
The previous chest pack had jammed his helmet, blocked his vision and constrained his movement during descent and the critical landing.
During the recent tests, body positions and suit deflation went well enough that the team accomplished all of its objectives.
Dive to death
No simple showman, Baumgartner wondered if the dangerous pioneering mission would mean his own death.
"My biggest concern is that dangerous part of the project which we just haven't thought of," Baumgartner said in a statement. "We try to think of every contingency, but there's always going to be something that you would never imagine could happen. And that might kill you."
The possibility has proved daunting enough to impact his decision to invite his own mother to watch the dive.
"If everything is successful, I would love to have her on site, because the first person that I would want to talk with is my mom, of course," he said. "But if something goes wrong, I definitely don't want my mum on site, because I don't want her to witness a fatality. So I still haven't made up my mind."
According to a press officer for Red Bull, the actual experiment will take place somewhere in North America in 2010. Along with a range of experts and test pilots, mentor and former record-setter Joe Kittinger will also be present.
- Edge of Space Found, Photo Gallery
- Video - Skydiving From the Edge of Space
- Graphic: Earth's Atmosphere From Top to Bottom