CEDAR FALLS - With a twist of his wrist and a flick of a finger, Pete Rosas executed a series of dizzying backwards somersaults and a nose roll. All with his feet firmly planted on solid ground.

Rosas drove from Council Bluffs with a fleet of radio-controlled planes for a miniature air show in the UNI-Dome Saturday.

While the tricks Rosas does with his craft take practice and skill, the technology he used to build it isn't nearly as out of reach.

"It's really because of cell phones," said Rosas.

Radio control enthusiasts converted cell phone batteries to power the motors. Early motors were often cannibalized from CD players. Rosas's motors and batteries are made specifically for the hobby, but the concepts are still the same.

The body of the biplane is made of foam and the whole plane, engine, controls and all, weighs 5 ounces. Its price tag was light as well at less than $300.

While some radio-controlled planes boast up to a 12-foot wingspan and 16-horsepower engines, most of the ones showing their stuff at the UNI-Dome were small, light-weight and acrobatic.

"You're looking at our escape right here," he said. Rosas showed off a "3-D" flyer that can do acrobatic flips and hover, nose up, in the air like a helicopter.

Rosas was among more than 80 radio control pilots from throughout the Midwest to come to Cedar Falls for the weekend event.

While the weather outside may have kept some away, the weather indoors was too tempting.

"It's always 72 and sunny at the Dome," said Brian Jebe, of the Black Hawk Radio Control Pilots Club. "They've got to get their fix. Winter is just too long around here."

It's also a chance for fellow flyers to catch up, show off, and browse the latest merchandise.

Katie Kmezich, 13, of Omaha, Neb., took the opportunity to hone her skills in a friendly environment.

"Pull to the right," suggested Fred Tuckerman, also of Omaha, who was flying tandem with Kmezich.

The lesson went well but ended abruptly with a hard landing.

"I think part of the wing broke off," she said on impact.

"No, it's just the propeller," Tuckerman added.

For some of the aerobatics displayed Saturday, a breeze of more than 3 miles per hour is enough to push some of the light-weight planes off course.

On Saturday the only hazard was other planes - especially during the air battle. In the afternoon "free-for-all," pilots deliberately take out as many other planes as possible.

"We go until it's last-man-flying," said Jebe.

Other events included pylon racing and aerobatics displays by planes and helicopters.

The Black Hawk Radio Control Flyers are always looking for new members and offer free training, Jebe said. Anyone interested can contact him at 230-1240.

The event continues today. Admission is $5, but children 12 years old or younger are admitted free.

Contact John Molseed at (319) 291-1418 or john.molseed@wcfcourier.com.