What was found
NR 1 ENGING FIRE DETECTION LIGHT ILLUMINATED DURING FLIGHT. INSPECTED SYSTEM. NO FAULTS FOUND. REPLACED BOTH AFT UPPER & LOWER FIRE DETECTORS. SYSTEM TESTED. AIRCRAFT RETURNED TO SERVICE. FAULTY PORTION OF THE NR 1 FIRE DETECTION SYSTEM WAS REPLACED FOR MULTIPLE NICKS IN THE WIRE SHIELDING AND SUSPECTED FAULTY SPLICES. NO FURTHER REOCCURRENCES HAVE BEEN REPORTED. SUPPLEMENTAL INFORMATION; THE DETECTORS IN THIS A/C HAVE BEEN REPLACED WITH P/N 477223 FLAME DETECTORS IAW COLUMBIA HELICOPTERS, INC. SERVICE BULLETIN NUMBER 107-26-S0004. DETAILS ARE ON FILE WITH OPERATOR CHIA823C.