David E. Steitz
Headquarters, Washington            July 23, 2002
(Phone: 202/358-1730)

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

RELEASE: 02-135

NASA TO STUDY LIGHTNING STORMS USING HIGH-FLYING UNINHABITED 
VEHICLE

     To better understand both the causes of an electrical 
storm's fury and its effects on our home planet, NASA and 
university research scientists will use a tool no 
atmospheric scientist has ever used to study lightning -- an 
uninhabited aerial vehicle. 

The research is part of the Altus Cumulus Electrification 
Study (ACES), a collaboration among NASA's Marshall Space 
Flight Center, Huntsville, Ala.; the University of Alabama 
at Huntsville; NASA's Goddard Space Flight Center, 
Greenbelt, Md.; Penn State University, University Park; and 
General Atomics Aeronautical Systems, Inc., San Diego. 

Based at the Naval Air Station Key West in Florida, 
researchers in August will chase down thunderstorms using an 
uninhabited aerial vehicle, or "UAV" -- allowing them to 
achieve dual goals of gathering weather data safely and 
testing new aircraft technology. This is expected to mark 
the first time a UAV is used to conduct lightning research.

"What we learn has the potential to help forecasters improve 
weather prediction, especially for storms that may produce 
severe weather," said the study's principal investigator, 
Dr. Richard Blakeslee, a NASA atmospheric scientist at the 
Global Hydrology and Climate Center in Huntsville. "Also, by 
learning more about these individual storms, we hope to 
better understand weather on a global scale.

"Using the aerial vehicle, we will make electric, magnetic 
and optical measurements of the thunderstorms, gauging 
elements such as lightning activity and the electrical 
environment in and around the storms," explained Blakeslee. 
"At the same time, ground-based radar and satellite 
observations will provide detailed information on the cloud 
properties and storm severity." 

This ground- and satellite-based data will include details 
on lightning flash rate, amount of precipitation and speed 
of updraft -- providing a comprehensive view of the storm 
from the ground, as well as from the sky.

By learning more about individual storms, scientists hope to 
better understand the global water and energy cycle as well 
as climate variability. The study also will provide federal, 
state and local governments with new disaster-management 
information for use during severe storms, floods and 
wildfires.

In the process, researchers will learn more about UAV 
aircraft and how they can be used for future research 
missions. "The UAV is an exciting new technology," said 
Blakeslee. "By getting this close to storms, we're 
demonstrating the promise of using uninhabited aerial 
vehicles for meteorological applications." 

"The mission will utilize the Altus UAV -- built by General 
Atomics Aeronautical Systems -- chosen for its slow flight 
speed of 70 to 100 knots (80 to 115 mph), long endurance, 
and high-altitude flight (up to 55,000 feet)," said ACES 
project manager Tony Kim of Marshall Space Flight Center. 
"The Altus boasts a wing span of 55 feet." These qualities 
give the Altus aircraft the ability to fly near 
thunderstorms for long periods of time, allowing 
investigations to be conducted over the entire life cycle of 
storms.

The Altus overcomes the limitations of conventional aircraft 
that, because of their greater speed, provide only brief 
snapshots of storm activity sandwiched between long periods 
of no observations.

As part of NASA's Uninhabited Aerial Vehicle-based, science 
demonstration program, these flights also will demonstrate 
this aircraft's ability to carry Earth-viewing scientific 
payloads into environments where pilots would be exposed to 
potentially life-threatening hazards. 

"In the summer, Florida is the best location in the United 
States to study thunderstorms because the large number of 
storms that occur there should provide frequent 
opportunities to observe them," said Blakeslee.

The mission is part of NASA's Earth Science Enterprise, a 
long-term research effort designed to help us better 
understand and protect our home planet, while inspiring the 
next generation of explorers.

                        -end-