What was found
AT 800 FEET CLIMBING OUT, ANTI-ICE DUCT OVERHEAT LIGHT ON, WHEN CORRESPONDING BLEED AIR SWITCHES CLOSED, NO HELP. WHEN NR 3 ENGINE POWER RETARDED LIGHT WENT OUT. RAN NR 3 ENGINE PER JET RUN, HANDBOOK CHAPTER 5 OPERATIONAL CHECK GOOD. FOUND RIGHT WING ANTI-ICE SWITCH IN OPEN POSITION AFTER LANDING, SUSPECT CAUSE OF OVERHEAT. CHECKED WING LEADING EDGE SURFACES, NO FAULTS NOTED PER STANDARD MAINTENANCE PRACTICES.