Accident Summary
A twin-engine airplane on a short cross-country flight crashed into a field approximately 7 miles short of its destination airport. The pilot had reported icing conditions and a discrepancy in airspeed indication before losing radio and radar contact. The airplane sustained fragmentation upon impact, but no pre-impact anomalies were found in the airframe or engines.
Flight and Weather
The flight departed in instrument meteorological conditions (IMC). While en route at 3,000 feet mean sea level, the pilot informed the controller that the airplane was accumulating ice and that he needed to increase speed. The controller cleared the pilot to descend and then to climb to exit the icing conditions. Shortly thereafter, a low altitude alert was issued, and the pilot responded that he was climbing.
Communication and Loss of Contact
Radar and radio contact with the airplane were lost shortly after the pilot indicated he was climbing. The airplane subsequently impacted a field near the destination airport.
Examination and Systems
The wreckage was extensively fragmented, limiting examination. No pre-impact anomalies were noted during airframe and engine inspections. However, the pitot static and deicing systems were too damaged to allow functional testing.
Avionics Data Analysis
Data from onboard avionics units revealed that around the time the pilot reported ice accumulation, the indicated airspeed began to diverge from ground speed calculated from position data. Minutes later, indicated airspeed dropped to zero while ground speed remained relatively constant. This discrepancy was likely caused by icing of the pitot probe.
During the final two minutes of flight, the airplane entered a left turn and received multiple "SINK RATE" and "PULL UP" warnings. The airplane executed a series of climbs and descents, with ground speed reaching or exceeding the airplane's maneuvering and maximum structural cruising speeds. The pilot likely became distracted by the erroneous airspeed indication and subsequently lost control while maneuvering.
Probable Cause
The official probable cause is a loss of airspeed indication due to icing of the airplane's pitot probe, and the pilot's loss of control while maneuvering.