The pilot and passengers had departed the San Angelo Airport at about 1800 CST on the day of the accident. They stopped at Midland, TX where they borrowed a courtesy car and drove to a restaurant. Later, the aircraft departed on a return flight. At about 2320 CST, the pilot made a radio call (intended to the San Angelo tower) and announced that he was 17 miles northwest for landing. The aircrew of Rio Airlines Flight 715 heard the transmission and informed the pilot that the tower was closed, but the runway lights were on. Shortly thereafter, the aircraft collided with slightly rising terrain in a near level flight attitude. The plane bounced and continued another 384 ft before the second ground impact. The main wreckage continued another 420 ft before it came to rest and burned. The impact area was in sparsely populated range land where there was an absence of lights. No preimpact malfunction or failures were evident.