An air data probe includes a probe head and an air data sensing port. The probe head defines a longitudinal axis extending from a forward tip of the probe head to an aft end of the probe head. The probe head has an elliptical cross section orthogonal to the longitudinal axis. The air data sensing port is disposed in the probe head aft of the forward tip. A length of a major axis of the elliptical cross section and a length of a minor axis of the elliptical cross section can be configured to cause boundary layer separation of airflow across the probe head at a flow separation region that is aft of the air data sensing port.