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[00:00.20]Gliders are light aircraft that fly with no engine.
[00:04.92]They are pulled by a powered plane into the sky
[00:08.16]and set free to fly on air currents.
[00:11.48]They soar on wind currents called "mountain waves."
[00:16.08]That is why their wings are longer than ordinary planes.
[00:21.40]The aerospace company Airbus Group
[00:24.68]recently completed the first flight of a glider it calls Perlan 2.
[00:30.53]The Perlan Project intends to use gliders to take measurements in the stratosphere.
[00:37.68]Scientists believe weather in the stratosphere affects the Earth's climate more than they thought before.
[00:46.68]Airbus plans to send Perlan 2 to an altitude of 27 kilometers next year.
[00:54.96]That is higher than the records set by the U-2 and SR-71 spy planes.
[01:02.44]Jim Payne is the chief pilot of Perlan 2.
[01:07.27]"We're not a thousand percent sure that the mountain wave will go that high,
[01:11.72]but all the meteorologists tell us that it does, so we're going to go out and find out."
[01:15.88]Ed Warnock is the chief executive officer of the Perlan Project.
[01:20.88]He says the project intends to discover how fast moving winds
[01:26.96]at altitudes between 10 and 50 kilometers influence the earth's climate.
[01:33.56]"It turns out some of the biggest waves in the world
[01:37.96]-- vertical movements -- exist in the stratosphere.
[01:41.12]We're going to go and study those waves.
[01:42.89]Those waves change weather and they change climate,
[01:48.56]and we are going to study how do they do that."
[01:51.40]Stratospheric winds may also influence commercial air traffic.
[01:57.04]Many airplanes fly at high altitudes to reduce fuel consumption.
[02:02.80]The air density, or thickness, at those altitudes
[02:07.28]is similar to the atmosphere on the planet Mars.
[02:11.64]This may lead to future aircraft designs
[02:15.12]that could someday fly through the skies of the Red Planet.
[02:19.56]I'm Jonathan Evans.