Cessna 421C

Service difficulty reports · 427

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Query with SQL
duckdb -csv -c "SELECT sdr_id, difficulty_date, n_number, aircraft_make, aircraft_model, part_name, part_condition, jasc_code, discrepancy
  FROM 'https://openairdocs.org/data/latest/faa_service_difficulty_report.parquet'
  WHERE aircraft_model_key = '421C'
  ORDER BY difficulty_date DESC"

Prints the whole list as CSV. It reads the release’s Parquet files over HTTPS, so there’s nothing to download first. Install DuckDB to run it.

SDR 2026FA0000551Gasket · degradedFAILED GASKET PN: 5154056-2 FOR THE AC COMPRESSOR, RESULTING IN A SEVERE ENGINE OIL LEAK, SPRAYING ENGINE OIL ON THE EXHAUST SYSTEM.Jun 30, 2026 · N68685 · Cessna 421C · Cabin Cooling SystemSDR 2026FA0000506Angle · crackedLEFT HAND UPPER ANGLE AT WING ROOT AND FUSELAGE CRACKS UNDER PRESSURIZATION/DEPRESSURIZATION WITH FLEX.Jun 10, 2026 · N543PM · Cessna 421C · Fuselage, Wing Attach FittingsSDR 2026FA0000505Wheel · cracked3-PIECE NOSE GEAR WHEEL ASSEMBLY CRACKS ON MIDDLE HUB ASSEMBLY #D30321.Jun 10, 2026 · N543PM · Cessna 421C · Wheel/Ski/FloatSDR 2026FA0000316Intake Duct · looseON 3 MAY 2026, APPROXIMATELY 11:55 AM, N123NP DEPARTED BIL FOR FBL AND FOUND THAT THE RIGHT ENGINE WOULDN'T MAKE RED LINE MAP AND ABORTED HIS TAKEOFF. MAINTENANCE FOUND A COUPLE INDUCTION TUBE CLAMPS LOOSE. THE MECHANIC TIGHTENED BOTH CLAMPS AND AND THE PILOT May 3, 2026 · N123NP · Cessna 421C · Engine Air Intake SystemSDR 2026FA0000153Attach Fitting · crackedLEFT WING FORWARD SPAR, OUTBOARD UPPER AFT-FACING WING ATTACH FITTING WAS FOUND TO BE CRACKED WITHIN GEAR WELL. THE PART IS SHOWN IN THE 421C IPC, SECTION 03-50, PAGE 16, ITEM 6. THE CRACK MEASURES ROUGHLY 5-1/8" AND RUNS HORIZONTALLY ACROSS SEVEN RIVET HOLES.Aug 20, 2025 · N421KM · Cessna 421C · Wing, Attach FittingsSDR 2025FA0000147Fuel Tank · leakingSHORTLY AFTER FUELING AIRCRAFT WITH GAMI G100UL BOTH MAIN TANKS STARTED LEAKING FROM MOST INSPECTION PANELS. ALSO A FUNCTIONAL CHECK OF THE FUEL SELECTOR VALVES INDICATES THAT THE RIGHT ENGINE SELECTOR VALVE IS STUCK IN POSITION.Mar 4, 2025 · N6867L · Cessna 421C · Fuel StorageSDR 2024FA0000146Propeller · overspeedRIGHT PROP GOVERNOR FAILED APPROACHING LEVEL OFF FROM CLIMB. ENGINE SPIKED TO OVER 6,000 RPM, ENGINE RUINED, BROUGHT PROP CONTROL BACK TO NO AVAIL. THROTTLE BACK AND MIXTURE BACK TO GET ENGINE RPM DOWN. VISUAL PROP COMPLETELY ?AT, PROP WOULD NOT FEATHER, RIDec 8, 2023 · N146T · Cessna 421C · Propeller SystemSDR 2023FA0000665Brake Disc · misrepairedINSTALLED A NEW DISC ON LT MLG. LT BRAKE PEDAL FLUCTUATES. CHECKED DISC, & FOUND TO BE .020 DIFFERENCE IN THICKNESS FROM ONE SIDE TO THE OTHER. PART NOT MACHINED PROPERLY.Oct 23, 2023 · Cessna 421C · Landing Gear Brake SystemSDR 2023FA0000268Cylinder · splitAN OCCURRENCE WAS REPORTED THAT HAPPENED AT RALEIGH AIRPORT (RDU), ON THE 05/09/2023 AT 1715 EDT. THE SAID AIRCRAFT, N382BW HAD JUST GOTTEN AIRBORNE AND RECEIVED AN ADVISORY FROM ATC THAT SMOKE WAS STREAMING FROM THE LEFT ENGINE. AIRSPEED WAS AT 97 KNOTS AND TMay 18, 2023 · N382BW · Cessna 421C · Reciprocating Engine Cylinder SectionSDR 2023F00043Cylinder · seizedWHILE IN CRUISE FLIGHT AT 19,000 FT, PILOT NOTICED THE RIGHT ENGINE SURGING. HE SUSPECTED IT WAS A FAILED FUEL PUMP AND WHILE ATTEMPTING TO REMEDY THE SITUATION, HE THEN NOTICED MAP DROPPING AND A COMPLETE LOSS OF OIL PRESSURE. THAT IS WHEN HE DECIDED TO SHUT Jan 26, 2023 · N421J · Cessna 421C · Powerplant SystemSDR 9FDR202104010001Selector Valve · misinstalledWHEN PERFORMING TEST OF ALTERNATE STATIC SYSTEM, THE INSTRUMENTS WOULD NOT SHOW A CLIMB OR DESCENT. THE AIR DATA TEST SET BEHAVED AS THOUGH THERE WAS A MASSIVE STATIC LEAK OR DISCONNECTED LINE. WHEN THE TEST SET WAS CONNECTED TO THE STATIC PORTS ON THE FUSELApr 1, 2021 · N3968G · Cessna 421C · Pitot/Static SystemSDR 2020FA0000524Gear · disconnectedPILOT NOTED THAT RIGHT ALTERNATOR FAILED IN FLIGHT. POST FLIGHT INSPECTION FOUND ENGINE GEAR, ALTERNATOR DRIVE, RETAINING BOLTS WERE NOT INSTALLED AND TWO WERE FOUND RESTING ON THE ALTERNATOR MOUNTING POINT INSIDE ENGINE CASE. OTHER TWO BOLTS WERE NOT FOUND,Nov 25, 2020 · N421BR · Cessna 421C · Engine (Reciprocating)SDR 2020FA0000442Spar · corrodedINSPECTED REAR SPAR AND FOUND CORROSION ON AFT SPAR RT SIDE WHERE DOUBLE PLATE IS RIVETED TO SPAR. INTERGRANULAR CORROSION BETWEEN THE DOUBLE AND SPAR. ALSO NOTED RIVETS ARE POPPING OFF DUE TO THE SEVERE CORROSION.Oct 9, 2020 · N6794D · Cessna 421C · Fuselage Main, StructureSDR HSRR2020022520Crossbeam · crackedAFT NACELLE CROSS BEAM CRACKED AT OUTBOARD MOUNT FLANGE.Feb 18, 2020 · N421GJ · Cessna 421C · Nacelle/Pylon, Main FrameSDR 6DFA2019042319001Heater · odorSMOKE IN CABIN DURING CRUISE. PIC TURNED ON HEATER AND FAN SWITCHES. NO HEAT, BUT FAINT BURNING SMELL. PIC LOOKED BACK SAW SMOKE AND SECURED HEATER.Apr 19, 2019 · N421LE · Cessna 421C · Heating SystemSDR 2018FA0000508Pressure Switch · failedIN SPITE OF NO REQUIREMENT TO TEST THIS PRESSURE SWITCH. FOUND THIS PRESSURE SWITCH FAILED IN THE CLOSED POSITION.Dec 11, 2018 · N605SR · Cessna 421C · Heating SystemSDR 2018FA0000484Connector · unsecureLEFT ENGINE TACHOMETER GENERATOR CANNONPLUG VIBRATED LOOSE DUE TO NOT BEING SAFETIED AND FROM VIBRATION OF ENGINE. CANNON PLUG REATTACHED AND SAFETIED. GROUND RAN ENGINE AND OPERATED NORMALLY. SUGGEST VERIFICATION OF CANNON PLUG BEING SAFTIED DURING NORMAL MAINov 16, 2018 · N200DC · Cessna 421C · Engine Indicating System WiringSDR 2018FA0000313Actuator · failedNOSE GEAR COLLAPSED DURING NORMAL LANDING, NOSE GEAR ACTUATOR FAILED - UNLOCKED.Jul 31, 2018 · N427JM · Cessna 421C · Landing Gear ActuatorSDR 1TLR20180425001Throttle Body · leakingDURING ANNUAL INSPECTION ENGINE RUNS, NOTICED FUEL LEAK EMINATING FROM THROTTLE BODY FUEL CONTROL SHAFT. LOCATION OF THE FUEL LEAK IS RIGHT ABOVE EXHAUST MANIFOLD.Apr 25, 2018 · N212R · Cessna 421C · Fuel Controlling SystemSDR CXUA201803210140Engine · failedRIGHT ENGINE FAILED.Dec 7, 2017 · N726RT · Cessna 421C · Engine (Reciprocating)SDR 2017FA0000517Drive Shaft · shearedPILOT REPORTED ON APPROACH TO LANDING, A MOMENTARY RIGHT ENGINE POWER FLUCTUATION, FOLLOWED BY RIGHT ALTERNATOR FAILURE, LANDED WITHOUT INCIDENT. POST FLIGHT MAINTENANCE FOUND ALTERNATOR DRIVE SHAFT SHEARED NEAR ALTERNATOR STATOR. THE ALTERNATOR DRIVE COUPLEROct 18, 2017 · N88606 · Cessna 421C · AC Generator-AlternatorSDR CSLR2017082900001Oil Cooler · crackedDURING ROUTINE POST OIL CHANGE INSPECTION, AN OIL LEAK WAS DISCOVERED ON THE OUTBOARD REAR CORNER OF THE LEFT ENGINE. INVESTIGATION REVEALED A CRACK OR VOID IN THE WELD ON BOTTOM OF THE OIL COOLER WHERE THE OIL LEAK ORIGINATED. REPLACED WITH NEW UNIT OPS OK.Aug 18, 2017 · N88606 · Cessna 421C · Engine Oil CoolerSDR 2017FA0000335Alternator · failedNOTICED HEAVY ELECTRICAL SMELL COMING FROM ALTERNATOR, FOUND BEARING SEIZING UP.Apr 20, 2017 · N410AJ · Cessna 421C · DC Generator-AlternatorSDR 2017FA0000333Alternator · failedLEFT HAND ALTERNATOR OPERATION INTERMITTENT AFTER INSPECTION CHECK RUN, FOUND ALTERNATOR STARTING TO SEIZE UP WITH DAMAGE TO CLUTCH ASSEMBLY.Apr 20, 2017 · N30LT · Cessna 421C · DC Generator-AlternatorSDR 2017FA0000332Alternator · failedNEW ALTERNATOR BEARINGS SEIZED AND SHEARED SHAFT. THIS IS ONE OF THREE WITH UNDER 300 HOURS SINCE NEW.Apr 20, 2017 · N307FM · Cessna 421C · DC Generator-AlternatorSDR 2017FA0000152Cylinder · damagedAT INSPECTION ALL CYLINDERSS, HAD LOW DIFFERENTIAL PRESSURE CHECK, FOUND GLAZING ON CYLINDERSS AND ALL EXHAUST VALVE GUIDES WERE WORN OUT. REPLACED.Apr 3, 2017 · N421HP · Cessna 421C · Reciprocating Engine Cylinder SectionSDR 2017FA0000364Lifter · spalledBOTTOM SURFACE OF LIFTERS SPALLING CAUSING DAMAGE TO CAMSHAFT.Mar 17, 2017 · N6794D · Cessna 421C · Reciprocating Engine Cylinder SectionSDR TO3R20170214001Air Filter · separatedOUR CUSTOMER REPORTED UNEVEN IDLE AND ERRATIC EGTS ON ALL CYLINDERS. AFTER TROUBLESHOOTING WE FOUND THAT ONE OF THE FILTERS WE REPLACED AT THE AIRCRAFTS LAST ANNUAL (18 HOURS AGO)HAD LOST THE INBOARD FELT SEAL AND PARTICLES WERE FOUND THROUGHOUT UPPER DECK REFeb 14, 2017 · N999DM · Cessna 421C · Engine Air Intake SystemSDR 2017FA0000405Line · failedTHIS HYDRAULIC LINE RUNS FROM THE EMERGENCY BLOW DOWN BOTTLE TO THE SHUTTLE VALVE IN THE NOSE COMPARTMENT. WHEN WE PULLED THE BLOW DOWN LEVER THE LINE BLEW OFF THE BOTTLE FITTING SO THE LANDING GEAR DID NOT COME DOWN. FOUND THE LINE HAD A SINGLE FLARE THAT FDec 19, 2016 · N421EM · Cessna 421C · Hydraulic System, MainSDR 2016FA0000278Cylinder Head · crackedPILOT WAS IN CRUISE AND THE RT ENGINE STARTED TO VIBRATE. AN ALTERNATE AIRPORT WAS SELECTED AND ENROUTE THE ENGINE STARTED TO LOOSE POWER. MAINTENANCE PERSONNEL REMOVED THE COWLING AND NOTED THAT THE NR 6 CYLINDER HEAD WAS SEPARATED FROM THE BARREL. CYLINDEJun 7, 2016 · N421AN · Cessna 421C · Reciprocating Engine Cylinder SectionSDR 17GR201605160002Housing · crackedCRACKED LT ENGINE FILTER HOUSING. CRACK DISCOVERED WHILE ADJUSTING THE ALTERNATE AIR DOOR. CRACK WAS ON THE FLANGE BETWEEN THE FILTER AND THE ALTERNATE AIR DOOR ASSEMBLY.May 13, 2016 · N421ES · Cessna 421C · Engine Air Intake SystemSDR 2016FA0000226Alternator · failedRIGHT ALTERNATOR FAILED. PULLED OFF THE ALTERNATOR AND FOUND BROKEN ALTERNATOR SHAFT 1" OTBD OF DRIVE COUPLING. CAME OFF ENGINE FROM ACFT.May 10, 2016 · N421ZM · Cessna 421C · AC InverterSDR 2016FA0000085Tube · leakingPILOT NOTED AN OIL LEAK ON THE LEFT ENGINE WHILE IN CRUISE FLIGHT AND REDUCED POWER WITH AN UNEVENTFUL LANDING PERFORMED. MAINTENANCE INSPECTED THE AIRCRAFT AND FOUND A LARGE HOLE IN THE BREATHER TUBE BETWEEN THE COMPRESSOR AND TURBINE LEAKING OIL AS WELL AS Jan 4, 2016 · N421FN · Cessna 421C · Turbine Engine Oil SystemSDR MLJA2016F00038Windshield · delaminatedPILOT WAS CLIMBING THROUGH 11,000 WHEN WINDSIELD DELAMINATED AND SPIDER CRACKED. PILOT MADE A PRECAUTIOANARY LANDING.Dec 18, 2015 · N421HP · Cessna 421C · Flight Compartment WindowsSDR CA151216014Engine · power loss(CAN) DURING CLIMB THE ENGINE LOST POWER WITH NO PRIOR WARNING OR ABNORMAL INDICATIONS. THE ENGINE WAS SECURED AND THE CREW PERFORMED AN UNEVENTFUL SINGLE ENGINE LANDING AT THE DEPARTURE AIRPORT. POST FLIGHT INSPECTION FOUND A SHEARED FUEL PUMP DRIVE SHAFT. THDec 10, 2015 · Cessna 421C · Engine (Turbine/Turboprop)SDR 2015FA0000556Intake Valve · failedPILOT REPORTED A VIBRATION IN THE LT ENGINE AND MADE A PRECAUTIONARY LANDING. UPON INVESTIGATION IT WAS FOUND THAT THE LT ENGINE HAD DROPPED AN INTAKE VALVE AND A HOLE HAD BEEN KNOCKED IN THE CASE BELOW THE MAGS.Nov 9, 2015 · N43BM · Cessna 421C · Reciprocating Engine Cylinder SectionSDR 2015FA0000480Engine · power lossLOSS OF POWER DURING CRUISE WITH A SUBSEQUENT UNSCHEDULED LANDING.Oct 6, 2015 · N6161X · Cessna 421C · Engine (Reciprocating)SDR 17GR159B092401Governor · failedAFTER ROTATION PROPELLER WENT INTO FEATHER AND ENGINE SHUT DOWN WITHOUT ACTION ON THE PART OF THE PILOT. GOVERNOR WAS FOUND TO BE BEYOND ECONOMICAL REPAIR. PROPELLER AND GOVERNOR O/H 1006.8 PRIOR TO THIS EVENT. PILOT WAS BALE TO CONTINUE CLIMB ON 1 ENGINE AND Sep 22, 2015 · N420RA · Cessna 421C · Propeller GovernorSDR NF2R201812210003Lifter · galledTHE LEFT ENGINE LIFTER ARE PITTED.Sep 4, 2015 · N421JH · Cessna 421C · Reciprocating Engine Cylinder SectionSDR YN8R201504280001Bearing · wornPILOT REPORTED NORMAL MAG DROP PRIOR TO DEPARTURE. IN CRUISE FLIGHT, PILOT FELT A SHUDDER IN THE AIRCRAFT AND LOST SOME POWER IN THE LEFT ENGINE. THIS WAS HIS DESTINATION. WE REMOVED THE COWLING ON THE LEFT ENGINE, REMOVED THE RT MAG AND FOUND IT VERY HARD Apr 21, 2015 · N421RS · Cessna 421C · Magneto/DistributorSDR 2015FA0000245Crankcase · crackedDURING A 100 HOUR INSPECTION, FOUND A SUSPECT CRACK ON THE RT ENGINE BETWEEN THE NR 1 AND NR 3 CYLINDERS. PERFORMED A DYE PENETRATE INSPECTION AND VERIFIED AN APPROXIMATELY 4" CRACK IN THE CRANKCASE EXTENDING FROM A THROUGH BOLT UP INTO THE CRITICAL AREA AS OUMar 11, 2015 · N88584 · Cessna 421C · Reciprocating Engine Power SectionSDR IGXR2014FA0000710Line · failedAFTER TAKEOFF, LT ENGINE STOPPED PRODUCING FULL POWER. AIRCRAFT SAFELY RETURNED BACK WITH 1 ENGINE. EXAMINED LT ENGINE AND DISCOVERED CYL NR 6 FUEL LINE DETACHED FROM FUEL MANIFOLD, LINE FAILED AT SOLDER JOINT AT MANIFOLD END. R & R CYLINDER NR 6 FUEL LINE Dec 15, 2014 · N122TJ · Cessna 421C · Aircraft Fuel Distribution SystemSDR 2014FA0000701Crankshaft · brokenCRANKSHAFT BROKEN AT NR 3 MAIN JOURNAL. POSSIBLE INTERNAL FLAW AT MANUFACTURING.Nov 20, 2014 · N8HT · Cessna 421C · Reciprocating Engine Power SectionSDR 2014FA0000358Clamp · failedFOD DAMAGE WAS FOUND ON LT ENGINE TURBO COMPRESSOR BLADES. THE SOURCE OF THE FOD DAMAGE WAS THE TAIL OFF FROM THE BAND CLAMP THAT HOLDS THE FILTER HOUSING ONTO THE TURBO. THE TAIL HAD AT SOME TIME SINCE LAST ANNUAL BROKEN OFF AND WAS SUCKED THROUGH THE GAP FJun 2, 2014 · N558BF · Cessna 421C · Engine (Turbine/Turboprop)SDR 2014FA0000266Nut · missingRT ENGINE NR 5 CYLINDER WAS DETERMINED TO HAVE 4 CYLINDER HOLD DOWN NUTS MISSING. UNABLE TO DETERMINE THE CAUSE. ENGINE REMOVED AND SENT OUT FOR REPAIR.Apr 23, 2014 · N459DM · Cessna 421C · Reciprocating Engine Cylinder SectionSDR FAA20140131000002Cylinder · crackedDURING SCHEDULED INSPECTION, NOTICED LIGHT COATING OF OIL TOP FWD CASE. CLEANED AND COMPLIED WITH CSB97-9 DYE CHECK. VERIFIED CRACK FWD TOP OF NR 5 CYLINDER. NOTED FLOW DIVIDER BRACKET BROKEN FWD AND AFT OF MOUNT. 166 HRS. SINCE RAM SERVICEABLE CASE INSTALLJan 9, 2014 · N421RX · Cessna 421C · Reciprocating Engine Cylinder SectionSDR IBUA2014F00048Sleeve · out of positionACFT WAS IN FLIGHT WHEN A FIRE WARNING LIGHT ILLUMINATED. PILOT ACTIVATED ENGINE EXTINGUISHER SYS AND WARNING LIGHT WENT OUT. DURING INSPECTION, FIRE SLEEVE PROTECTING ENGINE WIRE BUNDLE AFT OF ENGINE, ADJACENT TO INBD EXHAUST PIPE WAS FOUND TO BE TOUCHING Nov 14, 2013 · N745CA · Cessna 421C · Fire Protection System WiringSDR 2013FA0000674Boot · failedEYELET ATTACHMENT NOT FULLY INSULATED ALLOWING DIRECT SHORT TO GROUND ON ONE DE-ICE BOOT. THE SECOND WAS A FAILED INBD CIRCUIT.Nov 8, 2013 · N720FS · Cessna 421C · Airfoil Anti/De-ice SystemSDR CA131021001Engine · inoperative(CAN) SHORTLY AFTER TAKEOFF, THE ACFT CRASHED IN A FIELD WITHIN AIRPORT BOUNDARY. THE LT ENGINE WAS PRODUCING NO POWER. THE BEA HAS ASKED FOR ENGINE MFG ASSISTANCE FOR THE INVESTIGATION OF THE ENGINES WHICH WILL TAKE PLACE AT A LATER DATE.Sep 25, 2013 · Cessna 421C · Engine (Turbine/Turboprop)SDR YN8R201307310001Pump · leakingAFTER FUELING, PILOT NOTICED FUEL DRIPPING FROM GANG DRAIN BENEATH ENGINE. DISCOVERED FUEL WAS DRIPPING FROM ENGINE DRIVEN FUEL PUMP AT A RATE OF A DROP EVERY THREE SECONDS.Jul 31, 2013 · Cessna 421C · Engine Fuel Pump
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