A sensor for detecting icing conditions in an airstream includes a flow housing
mounted on an aircraft and in which one or more probes are mounted. At least one
of the probes subjected to impingement of the airstream and liquid moisture droplets
in such airstream. The heat removal, or cooling effect on the probe in the airstream
carrying liquid droplets is determined. A temperature signal indicating the airstream
temperature is combined with signals from the at least one probe for determining
whether or not icing conditions are present.