NEW YORK—A privately funded team will attempt this year to break a 50-year-old record for the highest-altitude parachute jump, floating a balloon well into the stratosphere before its pilot leaps out for a supersonic free fall.

The team behind the Red Bull Stratos mission announced details of the attempt here Friday morning in a media briefing. If all goes as planned, a towering helium balloon will loft Austrian-born skydiver and BASE jumper Felix Baumgartner, 40, roughly 37 kilometers into the air before he begins his descent. (BASE stands for "buildings, antennas, spans, Earth"—the places and structures from which a BASE parachutist jumps.) Baumgartner could set new records for the highest manned balloon flight and the longest free fall as well as become the first person to break the sound barrier without a protective craft. Baumgartner said he would exceed the speed of sound within about 35 seconds of free fall but would not pull his chute for another five minutes.

"It's human nature to want to go faster, farther," said Joe Kittinger, 81, the retired U.S. Air Force pilot who made the highest jump on record in 1960, parachuting from a balloon 31 kilometers above Earth's surface. Kittinger is the Stratos mission's capcom (short for capsule communicator), which means that he will be the voice in Baumgartner's helmet. Kittinger's advice to his successor: "Have fun, enjoy it, and tell us all about it when you get down."

Baumgartner, who called Kittinger a "childhood hero," is perhaps best known for gliding across the English Channel in 2003 with a carbon-fiber wing strapped to his back. Baumgartner said that jump, from about 10 kilometers, is his highest to date. The Stratos mission is incremental, with two lower-altitude jumps set to precede the final attempt; even the first jump, from roughly 20 kilometers, would double Baumgartner's personal altitude record.

The Stratos team claimed that Baumgartner's jump will be more than a dangerous stunt—Kittinger said that the collection of physiological data is central to the mission. Medical director Jonathan Clark noted that Kittinger's 1960 jump as part of the Air Force's Project Excelsior was in some ways a precursor to manned U.S. space missions, which began the next year. Similarly, Clark said, investigating the effects of a high-altitude bailout could benefit the fledgling commercial spaceflight industry.

Although many details of Baumgartner's proposed feats were on display, much of the mission's logistics remain opaque. Red Bull said only that the Stratos launch, for which a date has not been set, would be from North America; the company would not disclose the cost of the mission.

French skydiver Michel Fournier has attempted, without success, similar assaults on the record books in the past. At his most recent try in 2008, Fournier's balloon drifted away from its Saskatchewan launch site as it was being filled. The Web site for Fournier's project states that another attempt at a balloon jump from 40 kilometers will be made this year.