At about 1430 Pacific time, the two aircraft collided in flight while maneuvering to land. None of the three aboard the two airplanes was injured; the Piper sustained minor damage while the Glastar was substantially damaged. Visual conditions prevailed. As the Piper approached the runway to land, its pilot heard a thump and then saw the Glastar climb out from below. He noted damage to the Glastars rudder. The Piper landed; the Glastars pilot encountered control difficulties and flew to a nearby airport for an uneventful landing.