What was found
AFTER TAKEOFF APPROX 800 FT LEVEL 3, NR 2 ENGINE ANTI-ICE DUCT ILLUMINATED TRI TONE SOUND. SHUT DOWN ENGINE NR 2 AS PER VOLUME 1, DUMPED FUEL AS PER VOLUME 1 RETURNED TO FIELD, DEPARTURE FIELD JTY. REPLACED NR 2 ANTI-ICE VALVE. SWAPPED NR 2 AND NR 3 PRESSURE SWITCHES. CHECKED DUCT DAMAGE NOT FOUND ANY DAMAGE. ESC RTS TEST PASSED. ANNUNCIATE LIGHT TEST (R2-5527 RESET) AND THEN ENGINE RUN-UP CHECKED (GROUND IDLE RUN EPR 1.21) ANTI-ICE SYSTEM NORMAL. THE DUCT OVERHEAT SENSORS WERE REPLACED IN LAX D1-91 AND D1-89. (M)