What was found
MAIN ROTOR GEARBOX CHIP CAUTION LIGHT ILLUMINATED IN CRUISE FLIGHT. THE APPROPRIATE EMERGENCY PROCEDURE WAS FOLLOWED FOR THE CAUTION LIGHT (REDUCE POWER, LAND AS SOON AS POSSIBLE) AND A PRECAUTIONARY LANDING WAS MADE AT AN UNOCCUPIED SOCCER FIELD. INSPECTED CHIP DETECTOR AND PERFORMED FAULT ISOLATION TEST IAW AMM 05-50-00,6-1 AND AMM 60-00-00,1-1 AND FOUND NO DEFECTS. PERFORMED GROUND RUN AND COULD NOT DUPLICATE.