At approximately 13:30 MST, a Piper Dakota and a Diamond Katana were destroyed when they collided on the ground at the Provo Municipal Airport. The Piper was on its takeoff roll on runway 18 and the Katana was doing touch and go landings on runway 31. The three occupants of the Piper escaped injury, but the flight instructor aboard the Katana was seriously injured and his student pilot received minor injuries. The pilot of the Piper said he heard the pilot of one airplane announce that he was turning onto the base leg for runway 31. Another pilot announced, Ill follow you in. The pilot of the Piper announced that he would be taking off on runway 18 as soon as the other two airplanes had landed. When these two airplanes had landed, he began his takeoff roll. As the Piper approached the runway intersection, the pilot saw the Katana on its ground roll and approaching from his left. The Piper pilot closed the throttle and applied the hand brake, which locked up the brakes. He applied left rudder in an attempt to go behind the Katana. He then applied back elevator pressure and full left aileron in an attempt to raise the right wing over the top of the Katana. The Katana occupants had not been interviewed when the report was filed.