AeroVironment Inc.'s unmanned spy craft become vital reconnaissance tools on the battlefield.

Standing amid a grove of pepper plants in Thousand Oaks last week, Christopher Thompson revved up his plane's tiny 6-inch propeller and then gently tossed it into the sky, much as weekend hobbyists fly their airborne toys.

But this mini-aircraft called the Raven, weighing little over 4 pounds and painted in Army gray, is no ordinary model.

It is actually a tiny U.S. military spy plane that can hover quietly 500 feet in the air and transmit video images to operators several miles away. These Simi Valley-made planes are providing vital information to ground combat soldiers in Iraq and Afghanistan who want to know what's happening over the ridge and around the bend.

"It served us well," said Thompson, a private first class with the Army National Guard, as he demonstrated how his unit used the Raven in Afghanistan. There the aircraft helped his platoon avoid enemy ambushes and pinpoint the location of insurgent mortar fires. "It's an essential part of what we do in the Army now," he said.