Flight and Weather Briefing
The pilot of an airplane on a flight from the U.S. to Nassau, Bahamas, had obtained two preflight weather briefings via the Data User Access Terminal Service (DUATS), which included information that thunderstorms were forecasted. However, before departing on the return accident flight, the pilot did not request a weather briefing through DUATS or Lockheed Martin flight service station. While it is unknown whether the pilot obtained a briefing from Nassau Flight Service Station, thunderstorms with associated severe turbulence had been forecasted for the accident area well before departure and would have been available had the pilot requested a briefing.
Flight Path and Weather Conditions
After takeoff, the flight was in contact with Nassau terminal radar approach control, which had an inoperative primary radar. The airplane climbed to approximately 8,000 feet mean sea level and proceeded on a northwesterly heading with little deviation. The aircraft was equipped with color weather radar and a stormscope. Despite the availability of these tools, the flight penetrated level 6 radar returns with numerous lightning strikes in the area. Prior to this, the pilot did not request weather avoidance assistance or deviation from air traffic control.
Descent and Loss of Contact
The airplane began a steep descent after entering the intense weather. Radar and radio communications were subsequently lost. The wreckage and occupants were not recovered.
Probable Cause
The official findings state that the probable cause was the pilot's poor in-flight weather evaluation, which resulted in flight into a level 6 thunderstorm.