NASA lightning study achieves flight-duration milestone, monitoring four storms in single mission

Steve Roy Marshall Space Flight Center, Huntsville, Ala. (Phone: 256/544-0034)
UPDATE: N02-011

A NASA team flying an uninhabited aerial vehicle to study thunderstorms achieved a milestone Wednesday, Aug. 21, completing the study's longest-duration research flight --- six hours and 32 minutes - and monitoring four thunderstorms in succession.

Based at the Naval Air Station Key West, Fla., researchers with the Altus Cumulus Electrification Study (ACES) used the Altus II remotely piloted aircraft to study a thunderstorm in the Atlantic Ocean off Key West, two storms at the western edge of the Everglades and a large storm over the northwestern corner of the Everglades

"We gathered an extensive amount of data and had the opportunity to observe a variety of storm conditions, such as when the second and third storms merged into one larger storm," said the study's principal investigator, Dr. Richard Blakeslee, a NASA atmospheric scientist at the Global Hydrology and Climate Center in Huntsville, Ala. "We were fortunate to have a front-row seat to this meteorological event."

One of the most exciting data sets gathered, he added, was gleaned during the fourth and final thunderstorm of the day. "With cloud tops at 50,000 feet, it would have been nearly impossible to study this storm without the technology we have today. But thanks to recent advances in aviation, we now have remotely piloted aircraft that can reach these altitudes," he said.

The ACES lightning study uses the Altus II twin turbo uninhabited aerial vehicle, built by General Atomics Aeronautical Systems, Inc. of San Diego. Capable of high-altitude flight of up to 65,000 feet, the remotely piloted aircraft has the ability to fly near thunderstorms for long periods of time, allowing investigations to be conducted over the entire life cycle of storms.

"The aircraft was able to stay over and around the final storm for one hour and 20 minutes, gathering a vast amount of scientific information," Blakeslee said. "For this one storm alone, we gathered data on more than 500 optical and electrical triggers produced by lightning flashes."

With dual goals of gathering weather data safely and testing the adaptability of the uninhabited aircraft, the ACES study is a collaboration among NASA's Marshall Space Flight Center in Huntsville, the University of Alabama in Huntsville, NASA's Goddard Space Flight Center in Greenbelt, Md., Pennsylvania State University in University Park and General Atomics Aeronautical Systems, Inc.

The Global Hydrology and Climate Center is one of seven science research centers at the National Space Science and Technology Center (NSSTC) in Huntsville.