What was found
DURING CRUISE, MAIN ROTOR TRANSMISSION METAL PARTICLES LIGHT ILLUMINATE IN COCKPIT. LAND IMMEDIATELY IN SMALL CLEARING NEAR A ROAD. IT WAS A SECOND EVENT TO OCCUR WITHIN LAST 10 MINS, BUT FIRST TIME, WARNING LIGHT HAD EXTINGUISHED WHEN PILOT ACTIVATED PULSE CHIP DETECTOR SWITCH. FOUND A HAIR LIKE PIECE OF METAL, VERY SMALL. PROBABLY REMAINS OF A .003'' IN OF WIRE USE TO VERIFY OPERATION OF PULSE SYSTEM DURING PREVIOUS SCHEDULE INSPECTION. THE DETECTOR WAS CLEANED AND REINSTALLED, THE LIGHT REMAIN OFF. A 20 MINUTES GROUND RUN WAS CARRIED OUT. WARNING LIGHT REMAIN OFF. DETECTOR WAS REMOVED, INSPECTED (NO PARTICLE FOUND) AND REINSTALLED. A/C WAS THEN RETURNED TO SERVICE.