Tornadoes and planes can be a frightful combination.

So Adam Houston and his team will be very cautious with the $25,000, unmanned, radio-controlled plane they hope to fly near a tornado soon as part of an $11.9 million research project called Vortex2.

"We don't want to get too close because we don't want it to get sucked into the tornado," said Houston, an assistant professor in the University of Nebraska-Lincoln Geosciences Department.

Vortex2 stands for the Verification of the Origins of Rotation in Tornadoes Experiment. The National Science Foundation and the National Oceanic and Atmospheric Administration say it is the largest attempt in history to study tornadoes.

Its predecessor, a program called Vortex done in 1994 and 1995, documented the entire life cycle of a tornado for the first time. Vortex2 will build on Vortex's progress and help researchers determine why and how tornadoes initially form and how tornadoes are related to super-cell thunderstorms.

About 100 scientists and students, 40 research cars and trucks - many equipped with mobile radar and weather sensors - and four balloon-launching vehicles will converge on the central Great Plains between May 10 and June 13, repeating again from May 1 to June 15 in 2010.

Nebraska will be one of the states targeted by the Vortex2 scientific armada. Other areas include: southern South Dakota, western Iowa, eastern Colorado, Kansas, western Oklahoma and the Texas Panhandle. They are all in the twister-prone region called Tornado Alley.

"New advances from Vortex2 will allow for a more detailed sampling of a storm's wind, temperature and moisture environment, and lead to a better understanding of why tornadoes form - and how they can be more accurately predicted," Stephan Nelson, NSF program director for physical and dynamic meteorology, said in a statement.

Southeast Nebraska is part of the study area for Vortex2. However, Houston and his team will focus their research with their planes in southwest Nebraska, northwest Kansas and northeastern Colorado.

The reason: They need pre-authorization from the Federal Aviation Administration to fly the small, electric-powered, propeller-driven planes.

"They give us a certificate of authorization or waiver and it allows us to operate in a given geographic region with a specific aircraft," Houston said. "It turns out we have to apply for a lot of small areas."

Houston's 11-member team has approval to fly in 69 separate sites. It would be nice to cover the entire Vortex2 study region, Houston said, but it would take a lot of unmanned airplanes and they have only three.

"When the Vortex2 armada will target storms in this area, we will participate," Houston said. "Our deployment area is slightly different."

The planes will be operated from a computer at a base station. Each airplane will be equipped with a GPS autopilot that will follow - but not get ahead of - a chase vehicle, also equipped with GPS. Houston said FAA rules require visual contact with the aircraft at all times.

Houston and his team will target thunderstorms that have the potential to produce tornadoes. He hopes the data collected will help him and other researchers gain a better understanding of pre-existing air mass boundaries (such as cold and warm fronts) and their role in producing tornadoes.

"In the first Vortex, they found that 70 percent of tornadoes formed near these types of boundaries," Houston said. "There is a clear relationship but we don't know what that relationship is."

Houston, who has a Ph.D. in atmospheric sciences from the University of Illinois at Urbana-Champaign and a B.S. in meteorology from Texas A&M University, said the other key objective is to sample the rear flank downdraft that is very close to a tornado.

Two of Houston's graduate students have been involved in the project: Jamie Lahowetz, since the project's inception, and Tony Reinhart. Other students will be involved during deployments.

Houston and his team won't be out on the road constantly. Using forecasts, they will deploy to areas where there are good conditions for producing thunderstorms and then wait.

If everything goes right, they will get a plane within two or three miles of a tornado but not inside - like those little metal sensors in the movie "Twister."

Reach Algis J. Laukaitis at (402) 473-7243 or alaukaitis@journalstar.com.