Incident Overview
A crew departed Memphis, Tennessee, on a flight bound for Addison, Texas. En route, air traffic control cleared the aircraft to climb to flight level 300 (FL300). However, the aircraft continued climbing without authorization, reaching FL440.
Loss of Communication
Air traffic controllers attempted to contact the crew but were unsuccessful. In response, a United States Air Force Northrop T-38 Talon fighter was dispatched to intercept the aircraft. The fighter pilot confirmed that the cockpit windows were covered by frost and was unable to establish communication with the crew.
Flight Path and Crash
The aircraft continued its route southward, entering Mexican airspace. Shortly thereafter, both engines failed due to fuel exhaustion. The aircraft entered a dive and crashed near Cuatro Ciénegas, Mexico. The impact was severe, causing the aircraft to disintegrate.
Fatalities
Both pilots were killed in the crash. Among the deceased was Susan Reynolds, a 27-year-old NASA astronaut-candidate.
Official Findings
The probable cause, as determined by the official investigation, is believed to be a failure of the cabin pressurization system during flight. This led to a slow decompression of the cabin. The crew likely lost consciousness and died after suffering hypoxia. After the fuel was exhausted, both engines failed, resulting in a rapid descent and crash.