What was found
AIRCRAFT DEPARTED WARNER ROBBINS AFB IN LIGHT RAIN SHOWERS. AS ACFT BROKE THREW OVERCAST LAYER, RT ENG FIRE WARNING LIGHT ILLUMINATED. FLIGHT CREW MONITORED ENG PARAMETERS AND ENG COWLING. NO ABNORMAL CONDITIONS NOTED. CHECK LIST REVIEWED AND ACFT RETURNED TO WARNER ROBBINS AFB, UNEVENFUL LANDING MADE. ACFT TURNED OVER TO MAINTENANCE. INSP FOUND MOISTURE CONTAMINATION OF THE UPPER AFT. FIRE DETECTOR, PIN 30-215-8. NECESSARY REPAIRS MADE AND ACFT RETURNED FOR SERVICE. SUBMITTER SUGGESTS MFG IMPROVE SEALING METHOD OF WIRING TO DETECTOR.