What was found
NR 1 ENGINE FIRE WARNING INDICATOR ILLUMINATED DURING FLIGHT. ENGINE WAS SHUTDOWN, ONE FIRE BOTTLE WAS DISCHARGED AND FIRE WARNING CEASED. TEN MINUTES LATER FIRE WARNING RE-ILLUMINATED AND SECOND BOTTLE WAS DISCHARGED, FIRE WARNING LIGHT CEASED. FIRE WARNING LIGHT ILLUMINATED AND BELL CAME ON ABOUT SIX MORE TIMES BEFORE LANDING IN ICT. A CRACK WAS FOUND IN THE 8TH STAGE DUCT WITHIN THE FIXED COWL AREA. DUCT WAS REPLACED AND LEAK CHECKED AT TAKE-OFF POWER, NO LEAKS NOTED.