A Douglas DC-6 hit the water off Canc£n Airport, Mexico, during a test flight. One pilot and two passengers died in the accident. The aircraft departed Canc£n Airport at 09:22 hours on a test flight to Cozumel, without the intention to land there, and back to Canc£n. The intention was to verify the operation of the engines. In the flight plan the pilot noted that would fly at 2000 feet. At 15 miles from Cozumel, the flight requested authorization from the control tower of Canc£n to descend. This was approved. The aircraft descended in unfavorable weather conditions (rain) until it hit the water. The pilot in command and a passenger suffered serious injuries. The co-pilot was fatally injured and the other two passengers were reported missing. Probable cause: Performing an altitude loss operation, in low visibility conditions, with an exaggerated descent angle considering the flight level (2000 feet) over water, not allowing space for the recovery of the aircraft, until impacting the water surface.