What happened
A Lockheed C-141 was conducting the initial leg of a flight from Athens to Madrid, destined for McGuire AFB. While performing an ILS approach to runway 23 at Torrejón Air Base under overcast conditions, the crew failed to execute the Descent Checklist. This omission resulted in the altimeters remaining set to 29.92" instead of the local setting of 30.17", and the radar altimeter was not activated.
During the descent, a clearance from air traffic control was obscured by heavy radio congestion. The crew misinterpreted the instruction, believing they were cleared to descend to 3000 feet rather than 5000 feet. Although the error was communicated in a readback and subsequently during a position report, the mistake went uncorrected by controllers. As the aircraft approached 3000 feet, the navigator identified terrain ahead, but the pilot believed the path was clear due to visible airfield lights below.
At an altitude of 3050 feet and a speed of 250 knots, the aircraft struck a plateau edge approximately 40 km east of the base. The impact caused the plane to briefly lift into the air before rolling over and breaking apart in a nearby field. The accident resulted in 25 fatalities and one survivor.
Findings
Investigations determined that there were no mechanical or instrumental failures present on the aircraft. The primary cause was the crew's failure to adhere to standard approach procedures, leading to an unauthorized descent into terrain following a misheard clearance. Contributing factors included poor crew coordination, an improper planned approach, and significant crew fatigue, as the personnel had only received eight hours of rest within a 60-hour period.