Get the Mach newsletter.
By Tom Metcalfe

Riding the wind above the Andes Mountains, an experimental glider has set a world record for high-altitude flight.

On Sept. 2, the sleek Perlan 2 glider carried two pilots to 76,100 feet, or more than 14 miles, over the El Calafate region in southern Argentina. That’s the highest altitude ever reached by humans aboard an unpowered fixed-wing aircraft, and one of the highest altitudes reached by an aircraft of any description. Only spy planes and specialized balloons have flown higher.

The tail camera of the Airbus Perlan glider captured this view from a world-record setting altitude.Airbus

“The biggest impression is, it's a long ways down from up here,” one of the pilots, Jim Payne, said after the record-setting flight, which was one in a series of test flights sponsored by aerospace giant Airbus. “The horizon starts to have a curvature in it and the sky is getting darker as we climb. … It's a fantastic experience, once in a lifetime.”

The record eclipses one set during a previous Perlan 2 flight over El Calafate on Aug. 28, which reached an altitude of 65,600 feet.

But the recent outing, which took about five hours, wasn’t just about establishing bragging rights. Ed Warnock, the aerospace engineer who heads the Perlan Project, a Beaverton, Oregon-based nonprofit that designed and built the $3 million glider, said data collected by the glider would help provide a better understanding of high-altitude air currents. That could help commercial pilots avoid dangerous but invisible regions of turbulence.

Perlan 2, which is made of carbon fiber composite material, has an unladen weight of 1,540 pounds, according to Payne. Its wingspan is 84 feet — about twice that of a fighter jet.

Since the Perlan 2 glider is unpowered, its onboard instruments can measure the speed, temperature and chemical composition of high-altitude winds without interference from a hot, exhaust-spewing engine. “This cannot be done with a propeller flight or jet, or from [a] satellite,” Jie Gong, an atmospheric scientist with NASA's Goddard Space Flight Center in Greenbelt, Maryland, told NBC News MACH in an email.

El Calafate is one of the few places in the world where high mountains interact with fast-moving polar winds, a phenomenon that gives rise to powerful “mountain waves” that rise as high as 100,000 feet. Payne said he and his co-pilot, Tim Gardner, reached the record-setting altitude by riding areas of uplift in the waves after an airplane towed the glider to 40,000 feet.

The new altitude record might not last long. Payne said the weather conditions needed to reach high altitudes in the El Calafate region will persist for about another 10 days, adding that he and other pilots involved in the flights hope to reach 90,000 feet in the coming days before the Perlan 2 is packaged up and returned to the U.S.

Want more stories about the future of aviation?

FOLLOW NBC NEWS MACH ON TWITTER, FACEBOOK, AND INSTAGRAM.