On October 6, 008 at approximately 1332 central daylight time (CDT) a Cessna 421C, Mexican Registration XB-KWB was destroyed while attempting to return to Xoxocotlan International Airport (OAX,) Oaxaca, Mexico to land . Both aircraft occupants sustained fatal injuries. The aircraft intended destination was Huatulco Airport (HUX), Huatulco, Mexico. At approximately 1327 the pilot radioed a request to return and land, on runway 01 at OAX. The runway was in use and the pilot initiated a left 360 degree low altitude turn for spacing. The aircraft impacted runway 01 left wing low and slid to the right side of the runway coming to rest approximately 342 feet from initial impact on a heading of 200 degrees. A witness in a Cessna 206 on final approach behind the accident aircraft indicated that the 421 was in a left steep turn trying to reach the runway when the left wing impacted right of the center line of Runway 01. On scene investigation by the DGAC with assistance from technical advisers from Cessna Aircraft and Teledyne Continental Motors indicated that the flaps where up and the landing gear down. There was no fire. The right propeller blades were separated from the hub and showed no signs of engine power. Only two blades from the left propeller were found. One blade was still attached to the hub. Both blades showed signs of engine power. Four propeller blade marks, 24" apart were found on the right side edge of Runway 01. The investigation is under the jurisdiction of the Government of Mexico. This report is for information purposes only and contains only information released by the Government of Mexico. Further information pertaining to this accident may be obtained from: Secretaria de Comunicaciones y Transportes (SCT) Direccion General de Aeronutica Civil (DGAC) Col. san Juan de Arrgon, 3-seccion Del. Venustiano Carrabza Mexico, D.F, Mexico c.p. 15620 Telephone: 55-2598-0138