Jun 23, 2009
Incident
Kagoshima
InjuriesNone
Phase of Flight-
ConditionsIMC
OperationFAR NUSC
Probable Cause
Brief and temporary blockage of the pitot probes in cruise flight, most likely due to ice crystals aloft, leading to erroneous airspeed indications and airplane automation degradation as designed. Contributing to the incidents were design features of the Thales AA probes which left them more susceptible to high altitude ice crystal icing than other approved pitot probe designs.
NTSB DCA09IA064