Incident Overview
On the evening of the accident, N75KW, a Douglas DC-3, initiated takeoff from West Palm Beach at 19:40. The crew rejected the takeoff after reporting a lack of airspeed indication and returned to the ramp. Inspection revealed that both pitot tubes were covered or partially covered with mud dauber nests. The airspeed indicator was tested and found to be functioning, after which the flight departed from runway 09L at 20:35.
Flight History
The crew was cleared to climb to 5,000 feet, intercept Bahama Route 63V (BR 63V), and proceed on course. At 20:49:23, Miami Center cleared N75KW for the approach to Freeport and directed the aircraft to cross the Halbi intersection at 4,000 feet. Around 20:57, Freeport approach control cleared the flight to descend to 1,400 feet for a VOR approach to land on runway 24 at Freeport, which was acknowledged. This was the last radio contact with the flight.
Weather Conditions
The DC-3 descended into the sea in low ceilings, low visibility with moderate turbulence and thunderstorm activity.
Official Probable Cause Findings
The official investigation stated: "Unable to determine the probable cause of this accident from the available evidence." However, the board noted several factors that may have contributed: 1) Flight into known thunderstorm activities and turbulence; 2) Pre-existing discrepancies in the pitot/static system of the aircraft and their effect on the reliability of the flight instruments; 3) Lack of operational control exercised by the airline's management.