LOS ANGELES – NASA is planning a series of test flights of an unmanned flying wing that's designed to run on solar power and cruise for days at 100,000 feet, more than three times higher than commercial jets.
The first of as many as three flights could come this weekend from a Navy airstrip on the Hawaiian island of Kauai.
NASA developed the Helios Prototype with AeroVironment Inc. in a bid to build a pilotless aircraft that could replace space satellites for some applications.
"The goal is extreme-duration, sustained high-altitude, long-endurance flight for essentially Earth observing and telecommunications," said John Hicks, who manages NASA's Environmental Research Aircraft and Sensor Technology project at the Dryden Flight Research Center. "Basically, it's to try to get it up for six months at a time."
The plane has a 247-foot wingspan, greater than that of a Boeing 747, yet is only 12 feet long. It is too large to use the runways at the Pacific Missile Range Facility on Kauai, so it will take off and land from the crushed coral apron alongside the strip.
The first flight may reach only 70,000 feet, as engineers assess how well Helios performs. The second and third will attempt to reach 100,000 feet more than midway through the stratosphere to a height of 19 miles. Each flight is expected to last about 14 hours. If successful, the plane will set a record for sustained flight at that altitude.
The Helios Prototype last flew in 1999, when it completed a series of six flights in the Mojave Desert using battery power. This time, it will soar on power generated from the sun. The rectangular, translucent wing is covered with more than 60,000 solar cells.
AeroVironment, based in Monrovia, California, has produced other innovative aircraft in its 30-year history, including the Gossamer Albatross, a human-powered plane that crossed the English Channel in 1979. Its Pathfinder Plus flew to over 80,000 feet in August 1998, a record for propeller-powered aircraft.
Pathfinder Plus will fly again in 2002, when it will be used to aid Hawaiian coffee growers in a NASA-sponsored project to monitor ripening beans.
NASA and AeroVironment plan to fly Helios again in 2003, when they will attempt to keep the plane aloft for four days.