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 .