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The Perlan Project is a current research project to fly a sailplane to an altitude of 100,000 feet (30,480 meters).

Contents 1 Soaring 2 Objectives 3 Progress 4 Press Release for August 29, 2006 5 External links 6 References

Fair-weather thermal convection is a source of rising air used in the sport of gliding, but this is limited to the lower atmosphere in the convective boundary layer. Warm air can rise higher in thunderstorms, reaching the tropopause, the permanent temperature inversion between the troposphere and the stratosphere. Although pioneering glider pilots broke altitude records using thunderstorms, this practice is risky. Another method of reaching great altitudes was discovered by German glider pilots, including Wolf Hirth, in 1933 in the Riesengebirge.^[1] This method uses the powerfully rising and sinking air in mountain waves. Gliders regularly climb in these waves to high altitudes; as of 2007, the glider absolute world altitude record stands at 50,727 feet (15,460 m), the altitude reached by Steve Fossett and Einar Enevoldson under the auspices of the Perlan Project. The previous record was 14,938 meters (49,009 feet). It was set in 1986 by Robert R. Harris with a Grob G-102 over California City, California.^[2] Harris stopped at this altitude because he needed a pressure suit to climb higher.

Weaker standing waves exist beyond the tropopause in the stratosphere. The Perlan Project was conceived by former NASA test pilot Einar Enevoldson to demonstrate the feasibility of riding these stratospheric standing waves to even greater altitudes and thereby break the record. However the weather necessary to climb into the stratospheric waves are quite exceptional:

• The polar vortex overhead (occurring only in near-polar latitudes during winter)
• Prefrontal conditions
• A weak tropopause
• A gradual increase in windspeed with altitude
• Wind direction within 30° of perpendicular to the mountain ridgeline
• Cooperation of any present subtropical jet stream
• Strong low-altitude winds in a stable atmosphere
• Ridgetop winds of at least 20 knots

Phase one of the project, a proof of concept flight, has a goal of 62,000 feet (18,900 meters). Phase two, which will probably be attempted with a custom-built glider, has a goal of 100,000 feet (30,480 meters).

The project was based for a few years in Omarama, New Zealand, but it is currently based in Patagonia, at El Calafate, Argentina.

The glider is currently a modified DG Flugzeugbau 505M two-seater sailplane from which the motor has been removed to make room for batteries and liquid oxygen. The pilots are Steve Fossett and Einar Enevoldson and are equipped with full pressure suits.

"Into the Stratosphere – Without an Engine New world glider altitude record set by Fossett and Enevoldson in Argentina 50,671 feet (15,447 m) achieved by 'Perlan' - the first ever glider flight into the earth's stratosphere. Previous record shattered by 1,662 ft (507 m)". ^[3] (This claim subsequently ratified by Federation Aeronautique Internationale as 15,460 meters (50,727 feet).

• Perlan Project's official website (usually updated when flying season nears)