An old Minuteman 1 missile carrying an experimental nose cone veered off course shortly after launch from Vandenberg Air Force Base and had to be destroyed over the Pacific Ocean, the Air Force said. The missile's warhead was a dummy and there was no threat to public safety, said Capt. John Sullivan. The rocket was destroyed by a range safety officer when it went out of control about 115 miles east of Midway Island a short time after liftoff, officials said. The test was part of a program to develop and test new nose tip materials and warhead designs, Pentagon officials said. The aged Minuteman 1 has been replaced in the U.S. nuclear arsenal by Minuteman 2, Minuteman 3 and MX missiles, but is used by the Air Force as a booster to launch materials into space, said Air Force Capt. Sharon Walker.