As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NR 3 STANDBY PITOT, BECAME FULLY OBSTRUCTED AFTER A HEATING ELEMENT FAILURE. SHORTLY AFTER TAKEOFF ZERO AIRSPEED WAS INDICATED ON THE STANDBY INDICATOR AND THE ACFT RETURNED TO DEPARTURE. THE PROBE WAS FOUND TO BE OBSTRUCTED WITH A BLACK TAR LIKE SUBSTANCE. THIS WAS PRESUMABLY WHAT ENCAPSULATED THE HEATING ELEMENT. THE SAME SUBSTANCE WAS FOUND COMING FROM THE PITOT DRAIN AND TRAILING DOWN THE FUSELAGE. NO CAS MESSAGES POSTED THAT INDICATED A PROBLEM WITH THE AIR DATA HEATING SYSTEM. THE FAILED PROBE HAS BEEN SENT FOR INVESTIGATION.