UPDATE 3-Daredevil set for supersonic skydive over New Mexico

* Launch now targeted for 1:15 p.m. EDT (1715 GMT

* Stunt would break altitude record and sound barrier

(Recasts with new launch time, details)

By Irene Klotz

Oct 9 (Reuters) - A n Austrian daredevil made last-minutepreparations on Tuesday for a death-defying s kydive from aballoon 23 miles (37 km) over the New Mexico desert af ter delaysdue to winds earlier in the day.

Felix Baumgartner, a 43-year-old helicopter pilot, hot-airballoonist and professional skydiver, would break a longstandingaltitude record and the sound barrier if the jump goes forward.7

Baumgartner's team said the launch of a massive but fragilehelium balloon that would carry him u p t o 120,000 feet (36,576meters) above Roswell, New Mexico, had been sc heduled for about1:1 5 p.m . EDT (1715 GMT ).

The launch was delayed by about four hours b ecause of windsabove the l aunch site, the team said in a statement.

After they died down Baumgartner, wearing a pressurizedspacesuit, p repared t o climb into a specially made capsule thatwou ld c arry him into the stratosphere.

"(The) countdown is officially back on," Sarah Anderson, amember of Baumgartner's launch team, told Reuters by e-mail.

If the launch proceeds it would take about 2.5 to 3 hours toreach 120,000 feet.

The 30-million-cubic-foot (850,000-cubic-meter) plasticballoon, which is about one-tenth the thickness of a Ziploc bag,cannot handle winds greater than 6 miles per hour (9.7 km perhour).

Baumgartner hopes to break the record of 102,800 feet(31,333 meters) for the highest-altitude freefall, a milestoneset in 1960 by U.S. Air Force Colonel Joe Kittinger.

As he falls from 120,000 feet (36,576 meters) Baumgartnerwould also break the sound barrier. With virtually no air toresist his fall, he was expected to reach the speed of sound,which is 690 mph (1,110 kph) at that altitude, after about 35seconds of freefall.

He would stay supersonic for nearly a minute and shouldfreefall for a total of 5 minutes and 35 seconds.

When Baumgartner jumps from the capsule, the position of hisbody will be crucial, since there is no air for him to movearound in. If he falls in a way that puts him into a rapid spin,Baumgartner could pass out and risk damaging his eyes, brain andcardiovascular system

Baumgartner's safety gear includes his custom spacesuit thatwill protect him from low pressure and the extreme cold.Temperatures are expected to be as low as about minus 70 degreesFahrenheit (minus 57 degrees Celsius.)

The near-vacuum puts him at risk of ebullism, a potentiallylethal condition in which fluids in the body turn to gas and theblood literally boils. Severe lung damage could occur withinminutes.

Helicopters equipped with newly developed instruments totreat lung damage will be standing by during Baumgartner'sskydive.

"What we're doing here is not just a record attempt. It's aflight test program," project adviser Jonathan Clark, a medicaldoctor and former NASA flight surgeon, told reporters during anews conference on Monday.

Among those interested in the spacesuit research arecommercial companies developing spaceships for passenger travel.The research could help people survive a high-altitude accident.

Clark's wife, astronaut Laurel Clark, died along with sixcrewmates when the space shuttle Columbia broke apart over Texason Feb. 1, 2003, as it headed for a landing in Florida.

(Editing by Tom Brown and David Storey)

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