What was found
ENROUTE, THE NUMBER FOUR ENGINE FIRE WARNING SOUNDED AND AN ENGINE SHUTDOWN WAS ACCOMPLISHED FOLLOWING COMPANY PROCEDURES. THE FIRE WARNING EXTINGUISHED SHORTLY AFTER THE SHUTDOWN. MAINTENANCE INSPECTED THE ENGINE AND FOUND NO EVIDENCE OF A FIRE. THE ENGINE PNEUMATIC SYSTEM, FIRE LOOPS AND ASSOCIATED WIRING WERE INSPECTED AND TESTED IN ACCORDANCE WITH THE APPLICABLE PORTIONS OF THE DOUGLAS MAINTENANCE MANUAL, WITH NO DISCREPANCIES NOTED.