ROSWELL, NEW MEXICO // Extreme athlete Felix Baumgartner returned safely to Earth yesterday after a record-breaking 39-kilometre jump from the stratosphere. His dramatic, daring feat may also have marked the world's first supersonic skydive. Mr Baumgartner broke records for the highest-altitude manned balloon flight and the highest-altitude skydive before landing safely on his feet in the eastern New Mexico desert. He lifted his arms in victory shortly after landing, setting off loud cheers from friends and colleagues at the mission's control centre in Roswell. Sarah Anderson, a mission spokeswoman, said Mr Baumgartner had broken the sound barrier during his jump but he had failed to set a record for the longest free fall. None of the daredevil's landmark achievements can be classed as "official" until they are approved by the Federation Aeronautique Internationale (FAI). Based on preliminary figures, Ms Anderson said the jump lasted 9 minutes and 3 seconds, including the 4 minutes and 44 seconds after he deployed his parachute. Three hours earlier, Mr Baumgartner, known as Fearless Felix, had taken off in a pressurised capsule carried aloft by a 55-storey ultra-thin helium balloon. As he left the capsule, high above Earth, he flashed a thumbs-up sign, aware that his feat was being shown on a <a href="http://www.redbullstratos.com/" target="_blank" title="Visit the Red Bull Stratos website for more information.">live internet video</a> stream. During his jump, from more than three times the average cruising altitude of an airplane, the 43-year-old Austrian was expected to reach a speed of 1,110kph. Any contact with the capsule on his exit could have torn his pressurised suit, a rip that would have exposed him to oxygen deprivation and temperatures as low as -56°C. That could have caused potentially lethal bubbles to form in his bodily fluids. Mr Baumgartner's feat coincidentally coincided with the 65th anniversary of the successful attempt by the US test pilot, Chuck Yeager, to become the first man to break the sound barrier on an airplane. At Mr Baumgartner's insistence, about 30 cameras recorded the event yesterday. While billed as a live broadcast, the organisers introduced a 20-second delay, in case of accidents. Shortly after launch, screens at mission control showed the capsule as it rose 3,000 metres above the New Mexico desert as cheers erupted from organisers. Mr Baumgartner could also be seen on screens checking the instruments inside the capsule. His team included Joe Kittinger, who attempted to break the sound barrier from a height of 31km in 1960. With Mr Kittinger inside mission control yesterday, the two men could be heard going over technical details as the launch began. "You are right on the button, keep it right there," Mr Kittinger told Mr Baumgartner. An hour into the flight, Mr Baumgartner had ascended more than 19km and had gone through a trial run of the jump. Ballast was then dropped to speed up the ascent. Mr Kittinger told him: "Everything is in the green. Doing great." The jump marked the end of a five-year journey for Mr Baumgartner, already a record-setting high-altitude jumper. He had made two practice jumps in the area, one in March from 24km and another in July from 29km. Yesterday's adventure will also mark the end of his extreme altitude jumping career - he has promised this will be his final jump. Dr Jonathan Clark, Mr Baumgartner's medical director, had said he expected the pressurised suit to protect him from the shock waves of breaking the sound barrier. If all went well, Nasa could now certify a new generation of spacesuits capable of better protecting astronauts and providing an escape option from spacecraft at 36.5km, he said. Mr Baumgartner has said he now plans to settle down with his girlfriend and fly helicopters on mountain rescue and firefighting missions in the US and Austria.