Radio-Controlled Helicopter to Check Space Views of Land Cover

American and Japanese scientists are testing a radio-controlled helicopter sensor package over desert, grasslands, and forest this month as a new tool to check remote-sensing data on global vegetation from NASA's Terra satellite. University of Arizona and Japanese scientists will launch a six-week field campaign using a Japanese radio-controlled helicopter over several Earth Observing System (EOS) land validation core sites. These are internationally recognized sites that scientists use to check, or validate, remote-sensing information taken over the world's major ecosystems.

Yoshiaki Honda of the Center for Environmental Remote Sensing at Chiba University, Japan, developed the radio-controlled helicopter sensor package that will be used over validation sites in Arizona, New Mexico, Kansas, Montana, British Columbia, and Oregon.

The radio-controlled helicopter preparing for flights in Mongolia.

Contact:
Alfredo R. Huete, coordinator of the U.S. field campaign, University of Arizona Terrestrial Biophysics and Remote Sensing Program, Tucson, Ariz., (520) 621-3228; ahuete@ag.arizona.edu

Lori Stiles, University of Arizona News Services, Tucson, Ariz., (520) 621-1877; lstiles@u.arizona.edu

Science Goals:
Scientists from each of the EOS ground sites are coordinating their field measurements and satellite acquisitions with the planned helicopter overflights. The on-site measurements provide a "ground truth" of actual vegetation, soil, and land cover conditions, providing independent performance estimates of how well satellites can measure the land surface and its seasonal- and long-term changes.

"What makes this system unique is that the helicopter can get data from all possible angles," says campaign coordinator Alredo Huete of the University of Arizona. "That's very important to the satellite system, because the satellite views any given spot on Earth almost every day, but at different angles over all the different surfaces - desert shrub, or forest tree or grassland."

Infrastructure:
The helicopter carries an onboard spectroradiometer for measuring energy reflected from the ground surface. It can hover to an accuracy within 20 cm from its programmed point and carry a payload that weighs 30 kg at sea level, providing ample opportunity to mount a variety of sensors. The helicopter can be manually operated and guided by the Global Positioning System (GPS).

Honda's group prototyped and successfully tested their RC helicopter last year in the Mongolian grasslands, which is an EOS validation core site. Honda is principal investigator for Japan's Global Imager (GLI), a global vegetation monitoring experiment. Japan's space agency is planning to launch GLI aboard ADEOS2 in early 2001.

Location and Schedule:
Flights begin June 2-4 in the Tucson, Ariz., area. Additional flights are planned for Jornada, New Mexico (June 6-10); Carlsbad, New Mexico (June 11-12); Konza Prairie, Kansas (June 14-17); Missoula, Montana (June 18-23); Victoria, British Columbia, Canada (June 24-29); Otter, Oregon (June 30-July 3).