Aero Servicio de Sonora

Cessna 340

At approximately 0600, the aircraft departed Guerrero Negro, Mexico on an air taxi flight to Tijuana, Mexico. At 0715, the Tijuana weather was reported as partially obscured, visibility 1 mile with fog, haze and smoke, wind calm. During arrival, the pilot was cleared for an ILS runway 09 approach and reported over the final approach fix. However, the aircraft crashed at about 0759, before reaching the middle marker, which was 1/2 mile from the approach end of runway 09. Impact was on a ridge about 110 feet below the airport elevation and approximately 100 yards north of the international border. The aircraft was found a short time later by US Border patrol personnel. No preimpact part failure or malfunction was found. The 0800 weather at Tijuana was in part: sky partially obscured, visibility 1/10 mile with fog and haze, wind 210° at 4 knots. About 1 mile north at Brown Field, the weather was in part: sky partially obscured, visibility 3/4 mile with fog and haze, wind 280° at 4 knots. A toxicology check of the pilot's blood showed an alcohol level of 0.7‰. Calculations showed the sun would have been 16 ° above the horizon on a magnetic azimuth of 89.8°. All six occupants were killed.