N6674D

Part: SKIN — CORRODED (BS 410-477) · airframe 78,862 hrs

WHILE UNDERGOING INSPECTION, BUBBLING WAS DISCOVERED UNDER SEALANT OF THE RT UPPER CREASE ANGLE. ON DISASSEMBLY, FURTHER CORROSION WAS AROUND THE RADIUS OF THE UPPER AND LOWER ANGLES. REPAIRED THE ANGLES AND SKIN BS 410 TO 477.

Part: SKIN — CORRODED (BS 383-410) · airframe 78,714 hrs

DURING A BELLY WASH, IT WAS NOTICED THAT THERE WAS A SMALL "BULGE" ON THE BOTTOM SKIN OF THE LT TORQUE BOX. AFTER INSPECTION IT WAS DETERMINED TO BE CORROSION. REPAIRED THE SKIN.

Part: GROUND WIRE — BROKEN (FLAME DETECTOR) · airframe 78,596 hrs

WHILE IN ENROUTE THE NR 1 ENGINE FIRE LIGHT ILLUMINATED (6) SEPARATE TIMES FOR 3-5 SECONDS EACH TIME, WITH 1-2 MINUTES IN BETWEEN OCCURRENCES. PILOT LANDED AND TURNED ACFT OVER TO MAINT. BLUE GROUND WIRE WAS FOUND BROKEN OFF AT THE BACK OF THE NR 1 AFT O/B FIRE DETECTOR ALONG WITH CHAFED WIRE (W1G20) AT STA: 410, W/L: -12, BL: 40L. REPLACED NR 1 AFT O/B FIRE DETECTOR AND REPAIRED CHAFED WIRE.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. THIS SUPPLEMENTAL INFORMATION WILL BE REPEATED ON THE FOLLOWING SDR’S; CHIR20160608001, CHIR20161003001, CHIR20140217001, CHIR20140214001, CHIR20161006001. CHIR20161007001, CHIR20161008001, CHIR20161009001, CHIR20161121001, CHIR2879, CHIR3001092917, CHIR2957090717, CHIA201803163196, CHIA201810083560, CHIA201810063561, CHIA201907214031, & CHIA201907234035

Part: FINGER DOUBLER — CRACKED (FUSELAGE) · airframe 78,452 hrs

CRACK FOUND AT STA 410 WL+2.7 BL 43L FINGERPLATE. REPLACEMENT AND REINFORCEMENT IAW SERVICE LETTER# 107-0165, REV.0.

Part: WIRE HARNESS — CHAFED (FIRE DETECTOR) · airframe 78,345 hrs

DURING FLIGHT, THE NR 1 FIRE HANDLE WARNING LIGHT ILLUMINATED. FALSE FIRE WARNING, FLIGHT CONTINUED. DURING TROUBLESHOOTING, FOUND THE NR 1 FWD OUTBOARD FIRE DETECTOR TO HAVE VOLTAGE IN EXCESS OF 11 VOLTS ON PIN B OF THE LARGE CONNECTOR OF THE FIRE CONTROL AMPLIFIER. NORMALLY THIS WOULD INDICATE A DEFECTIVE FLAME DETECTOR. AFTER UNCLAMPING THE WIRE BUNDLE LEADING TO THE DC JUNCTION BOX, CONNECTOR 300P15, FOUND 8 WIRES CHAFED THROUGH THEIR INSULATING SHEATHING. REPAIRED THE WIRING AND RETESTED THE CIRCUIT, SHOWS THE FLAME DETECTOR FUNCTIONING PROPERLY. SUPPLEMENTAL INFORMATION; THE DETECTORS IN THIS A/C HAVE BEEN REPLACED WITH P/N 477223 FLAME DETECTORS IAW COLUMBIA HELICOPTERS, INC. SB 107-26-S0004.

Part: SEAL — FAILED (TRANSMISSION) · airframe 76,680 hrs

THE AFT TRANSMISSION, PN 107D2010-34, SN TA-9-22 WAS REMOVED FROM ACFT FOR A SCHEDULED INSPECTION. WHILE IN THE SHOP, THE BLOWER DRIVEN SEAL RETAINER WAS REMOVED FROM THE MIX BOX TRANSMISSION, PN: 107D2004-19, SN: A-11-111 IN ORDER TO SEE IF THE BLOWER DRIVEN SEAL HAD FAILED. DURING INSPECTION FOUND THE TAB RING HAD SEPARATED FROM THE SEAL AS 1 PIECE AND THE STEEL SPACER INSIDE THE SEAL HOUSING WAS ABLE TO BE ROTATED.

Part: FIRE DETECTOR — FALSE ACTIVATION (NR 2 ENGINE) · airframe 75,406 hrs

NUMBER 2 ENG FIRE WARNING SYS ILLUMINATED IN FLIGHT, FALSE FIRE WARNING.

Part: BOLT — WORN (AFT ROTOR) · airframe 73,136 hrs

DURING OPPORTUNITY INSPECTION, MX CREW NOTICED EXCESSIVE STEP WEAR ON AFT ROTOR PITCH CHANGE LINK (GREEN POSITION) UPPER BOLT. PITCH CHANGE LINK BOLT WAS SUBSEQUENTLY REPLACED.

Part: SUN GEAR — CRACKED (TRANSMISSION) · airframe 71,191 hrs

DURING POWER CHECKS, PILOTS REPORTED HEARING A LOUD "BANG" FROM THE REAR OF THE ACFT. AFTER SHUTDOWN, INSP AND RESTART, IT WAS NOTED THAT BOTH GENERATORS WERE OFFLINE. BOTH GENERATORS WERE FOUND TO HAVE SHEARED AT THE INPUT INTO THE AFT TRANSMISSION. AS A PRECAUTION, THE AFT TRANSMISSION WAS RETURNED TO THE SHOP FOR FURTHER EVALUATION. UPON EVALUATION AN EDDY CURRENT INSP INDICATED CRACKS IN THE ROOT AREA OF THE SUN GEAR. X-RAY INSP DID NOT OBTAIN ANY CRACK INDICATIONS. THE SUDDEN STOPPAGE OF THE AFT TRANSMISSION, DUE TO THE CLUTCH HANG-UP AND RESULTING SHEARED GENERATORS IS BELIEVED TO BE THE CAUSE OF THIS FAILURE.

Part: GENERATOR — FAILED (NR 1) · airframe 70,997 hrs

NR 1 GENERATOR LIGHT ILLUMINATED WHILE CIRCLING AND HOLDING WAITING FOR LANDING SPACE. A BRIEF PUNGENT ODOR WAS NOTICE AND ACFT DIVERTED TO ALTERNATE LANDING ZONE. THE ODOR DISAPPEARED UNTIL LANDING. AFTER LANDING AND SHUTDOWN IT WAS NOTICED THAT THE NR 1 GENERATOR HAD BLACK MATERIAL EXPELLED FROM THE VENT SCREEN. THE GENERATOR WAS REMOVED AND FOUND SHAFT SHEARED AT THE SHEAR POINT. THE BLACK MATERIAL WAS COMING FROM THE FRICTION MATERIAL OF THE DAMPER RING. 6 MAIN FEEDER WIRES ARE NOTED AS DISCOLORED FROM THE BLACK FRICTION MATERIAL AND HEAT AS WELL AS THE GENERATOR CONTROL WIRES.