# Service difficulty reports: Lycoming IO-540-AE1A5

A list on [Lycoming IO-540-AE1A5](https://openairdocs.org/engine/lycoming-io-540-ae1a5.md).

Newest first. General aviation reporting is voluntary.

Page 1 of 19 · 924 reports

- [SDR 2NVA20260622001](https://openairdocs.org/sdr/2NVA20260622001.md): Pump · inoperative · Jun 22, 2026 · N488JB · Robsin R44RAVENII · Fuel Boost Pump
  > LOW FUEL PRESSURE LIGHT ILLUMINATED IN FLIGHT. NO ENGINE ROUGHNESS. VERIFIED ELECTRICAL FUEL PUMP NOT RUNNING. REPLACED ASSY PN D743-3 ASSY PER MM. THIS IS A COMMON ISSUE WITH THE R44 RAVEN II.
- [SDR 2026FA0000623](https://openairdocs.org/sdr/2026FA0000623.md): Cylinder · scored · Dec 5, 2025 · N306VA · Robsin R44 · Reciprocating Engine Cylinder Section
  > THIS IS A NEW AIRCRAFT. LESS THAN 50HRS HAD BEEN FLOWN BEFORE WE FOUND ISSUES. LOGBOOK ENTRY, AIRCRAFT HAD A HARD STARTING CONDITION. FOUND STUCK INTAKE VALVES ON CYLINDERS 2, 4 & 5 WHILE DOING A COLD COMPRESSION CHECK. UPON FURTHER INSPECTION ALL THE EXHAUST
- [SDR 2024FA0000479](https://openairdocs.org/sdr/2024FA0000479.md): Boot · cracked · Mar 1, 2024 · N446TC · Robsin R44RAVENII · Propeller/Rotor Anti-Ice/De-Ice System
  > C156-2 WINTER BOOTS (FEATHER BEARINGS ON THE BLADES) DEVELOPED FRACTURES IN THE SILICONE WHERE STRESSES FROM STRETCHING AND DEFORMATION WAS CONCENTRATED. IT WAS NOT A CUT, AND APPEARED TO BE GRANULAR OR ALMOST LIKE FLOWLINES FROM MOLDING.
- [SDR YV3R2023111500586](https://openairdocs.org/sdr/YV3R2023111500586.md): Warning Unit · defective · Oct 19, 2023 · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED WARNING UNIT, LOW RPM P/N: A569-9 PART FAILURE, HORN LIGHT STAYS ON.
- [SDR 2023FA0000601](https://openairdocs.org/sdr/2023FA0000601.md): Muffler · distorted · Oct 17, 2023 · N654SA · Robsin R44RAVENII · Engine Noise Suppressor
  > EXHAUST SYSTEM HEAT DEFORMING. NEW MUFFLER SYSTEM INSTALLED @ 449.94 THEN AGAIN @912.12.
- [SDR YV3R2023100200582](https://openairdocs.org/sdr/YV3R2023100200582.md): Controller · intermittent · Sep 7, 2023 · Robsin R44RAVENII · Engine Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY (GOVERNOR) P/N: D278-2 WAS INTERMITTENT.
- [SDR YV3R2023100200580](https://openairdocs.org/sdr/YV3R2023100200580.md): Shield · cracked · Aug 29, 2023 · Robsin R44RAVENII · Engine Noise Suppressor
  > CUSTOMER REPORTED SHIELD ASSEMBLY P/N: D314-2 WAS FOUND CRACKED.
- [SDR YV3R2023082800578](https://openairdocs.org/sdr/YV3R2023082800578.md): Shield · cracked · Aug 25, 2023 · Robsin R44RAVENII · Engine Exhaust System
  > CUSTOMER REPORTED SHIELD ASSEMBLY P/N: D314-1 WAS FOUND CRACKED..
- [SDR YV3R2023092900579](https://openairdocs.org/sdr/YV3R2023092900579.md): Actuator · defective · Aug 25, 2023 · Robsin R44RAVENII · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-2 ONLY HAD ONE TENSION PLATE WORKING.
- [SDR 2023FA0000345](https://openairdocs.org/sdr/2023FA0000345.md): Intake Valve · separated · Jun 27, 2023 · N220SG · Robsin R44RAVENII · Reciprocating Engine Cylinder Section
  > PILOT REPORTED THAT DURING CRUISE FLIGHT ENGINE RPM BEGAN TO FLUCTUATE AND ENGINE BEGAN TO RUN ROUGH. PILOT IMMEDIATELY RETURNED TO BASE AND MADE A NORMAL LANDING. WHEN ON THE GROUND THE PILOT REPORTED THAT THE ENGINE WAS RUNNING ROUGH AND A SIGNIFICANT VIBRAT
- [SDR YV3R2023071000576](https://openairdocs.org/sdr/YV3R2023071000576.md): Altimeter · defective · Jun 23, 2023 · Robsin R44RAVENII · Altimeter, Barometric/Encoder
  > CUSTOMER REPORTED ALTIMETER P/N: A613-2 WAS STICKING AND SLUGGISH IN OPERATION.
- [SDR 2023FA0000278](https://openairdocs.org/sdr/2023FA0000278.md): Exhaust Valve · corroded · May 23, 2023 · N3206M · Robsin R44RAVENII · Reciprocating Engine Cylinder Section
  > DURING BORE SCOPE INSPECTION OF CYLINDER ASSEMBLIES THE NUMBER 3 CYLINDER EXHAUST VALVE WAS FOUND TO BEY HEAVILY PITTED ON VALVE BELL. THE ENGINE HAS ACCUMULATED 398.4 HOURS SINCE MAJOR OVERHAUL. NEW CYLINDER ASSEMBLIES INCLUDING VALVES WERE INSTALLED AT OVERH
- [SDR YV3R2023051600567](https://openairdocs.org/sdr/YV3R2023051600567.md): Relay · inoperative · May 10, 2023 · N944VB · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED RELAY ASSEMBLY P/N: B280-12 WAS INOPERATIVE (NO LOW RPM LIGHT OR HORN).
- [SDR YV3R2023051600568](https://openairdocs.org/sdr/YV3R2023051600568.md): Shield · cracked · May 10, 2023 · Robsin R44RAVENII · Engine Exhaust System
  > CUSTOMER REPORTED SHIELD ASSEMBLY P/N: D314-2 WAS FOUND CRACKED.
- [SDR 2024FA0000205](https://openairdocs.org/sdr/2024FA0000205.md): Clutch Actuator · broken · Apr 21, 2023 · N31471 · Robsin R44RAVENII · Engine/Transmission Coupling
  > AFTER PIC LANDED N31471 WITH THE COLLECTIVE FULL DOWN, THE CLUTCH LIGHT ILLUMINATED. AFTER LIGHT HAD BEEN ON FOR 10 SECONDS, PIC PULLED THE CLUTCH CIRCUIT BREAKER IN ACCORDANCE WITH THE R44 POH AND ROLLED DOWN THE THROTTLE. PIC THEN SHUT DOWN THE HELICOPTER IA
- [SDR YV3R2023042700563](https://openairdocs.org/sdr/YV3R2023042700563.md): Controller · defective · Apr 20, 2023 · N276RC · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2 OVER SPEEDS ENGINE AND ROTOR SYSTEM.
- [SDR YV3R2023042700561](https://openairdocs.org/sdr/YV3R2023042700561.md): Relay · faulty · Apr 18, 2023 · N8611C · Robsin R44RAVENII · Electrical Power System
  > CUSTOMER REPORTED RELAY, 40 AMP 24V, SPDT P/N: D260-4 SHORTED INTERNALLY.
- [SDR YV3R2023042700562](https://openairdocs.org/sdr/YV3R2023042700562.md): Cylinder · defective · Apr 18, 2023 · Robsin R44RAVENII · Emergency Flotation Section
  > CUSTOMER REPORTED CYLINDER ASSEMBLY P/N: D679-3 LEAKED BELOW ALLOWABLE INDICATION LIMIT.
- [SDR YV3R2023031500554](https://openairdocs.org/sdr/YV3R2023031500554.md): Shield · cracked · Feb 28, 2023 · N744HJ · Robsin R44RAVENII · Air Conditioning System
  > CUSTOMER REPORTED SHIELD P/N: D785-4 CRACKED IN HALF.
- [SDR YV3R2023031500552](https://openairdocs.org/sdr/YV3R2023031500552.md): Actuator · defective · Feb 16, 2023 · Robsin R44RAVENII · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-2 FAILED SWITCH TEST.
- [SDR YV3R2023031500553](https://openairdocs.org/sdr/YV3R2023031500553.md): Shield · cracked · Feb 16, 2023 · Robsin R44RAVENII · Engine Exhaust System
  > CUSTOMER REPORTED SHIELD ASSEMBLY P/N: D314-2 CRACKED.
- [SDR YV3R2023031400551](https://openairdocs.org/sdr/YV3R2023031400551.md): Controller · defective · Jan 4, 2023 · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2 GIVING A HIGH READING OF MORE THAN 101% RPM.
- [SDR YV3R2023031400549](https://openairdocs.org/sdr/YV3R2023031400549.md): Controller · malfunctioned · Dec 15, 2022 · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2 MALFUNCTIONED.
- [SDR YV3R2022111700548](https://openairdocs.org/sdr/YV3R2022111700548.md): Controller · defective · Nov 1, 2022 · Robsin R44RAVENII · Engine Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2 GIVES HIGH READINGS ON DUAL TACHOMETER.
- [SDR YV3R2022111700547](https://openairdocs.org/sdr/YV3R2022111700547.md): Dual Tachometer · defective · Oct 31, 2022 · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-5 FLUCTUATES CAUSING OVER RPM.
- [SDR 2022FA0000591](https://openairdocs.org/sdr/2022FA0000591.md): None · collapsed · Oct 4, 2022 · N911TM · Robsin R44RAVENII · Landing Gear System
  > THE AIRCRAFT LANDED UNEVENTFULLY AND WAS SHUT DOWN BY THE PILOT. AFTER SHUTDOWN THE PILOT INSTALLED THE GROUND HANDLING WHEELS AND BEGAN TO MOVE THE AIRCRAFT INTO THE HANGAR. WHILE GROUND HANDLING THE AIRCRAFT THE AFT RIGHT HAND LANDING GEAR STRUT BROKE AND CO
- [SDR YV3R2022100700544](https://openairdocs.org/sdr/YV3R2022100700544.md): None · failed · Sep 15, 2022 · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED WARNING UNIT ASSEMBLY (LOW RPM) P/N: A569-9 FAILED TO ACTIVATE LIGHT AND HORN.
- [SDR YV3R2022091400537](https://openairdocs.org/sdr/YV3R2022091400537.md): Coordinator · defective · Aug 24, 2022 · Robsin R44RAVENII · Navigation System
  > TURN COORDINATOR ASSEMBLY P/N: B329-1 WAS INOPERATIVE.
- [SDR YV3R2022091300535](https://openairdocs.org/sdr/YV3R2022091300535.md): Governor · defective · Aug 8, 2022 · Robsin R44RAVENII · Standard Practices/Structures
  > CUSTOMER REPORTED GOVERNOR ASSEMBLY P/N: B247-5 WAS UNSERVICEABLE (INTERMITTENT). TESTING RESULTS: INTERMITTENT IN WIRES APPROXIMATELY 0.5" FROM GROMMET.
- [SDR 2022FA0000525](https://openairdocs.org/sdr/2022FA0000525.md): Exhaust Valve · broken · Jul 21, 2022 · N144DM · Robsin R44RAVENII · Fuselage Structure (General)
  > DURING CRUISE FLIGHT ENGINE BEGAN TO RUN ROUGH AND MANIFOLD PRESSURE INCREASED. PILOT WAS ABLE TO RETURN TO THE HELIPAD AND MAKE A NORMAL LANDING. EXHAUST VALVE STEM WAS FOUND TO BE BROKEN AT THE BELL CURVE AND THE VALVE WAS IN THE CYLINDER BORE. SEVERE CYLIND
- [SDR 2022FA0000352](https://openairdocs.org/sdr/2022FA0000352.md): Exhaust Valve · broken · Jul 13, 2022 · N118YL · Robsin R44RAVENII · Powerplant System
  > NUMBER ONE CYLINDER EXHAUST VALVE STEM BROKE RELEASING VALVE INTO CYLINDER.
- [SDR YV3R2022071100533](https://openairdocs.org/sdr/YV3R2022071100533.md): None · defective · Jul 7, 2022 · N868MP · Robsin R44RAVENII · Air Conditioning System
  > CUSTOMER REPORTED EVAPORATOR ASSEMBLY P/N: D798-1 CAUSES COMPRESSOR TO SHORT CYCLE, AND DOES NOT COOL.
- [SDR 2022FA0000440](https://openairdocs.org/sdr/2022FA0000440.md): Exhaust Valve · broken · Jun 25, 2022 · N3055Y · Robsin R44RAVENII · Engine (Reciprocating)
  > EXHAUST VALVE BROKE AT STEM AND ENGINE SUFFERED PARTIAL LOSS OF POWER.
- [SDR YV3R2022071100532](https://openairdocs.org/sdr/YV3R2022071100532.md): None · defective · Jun 16, 2022 · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED GOVERNOR CONTROLLER ASSEMBLY P/N: D278-2 RUNS TO 106%.
- [SDR YV3R2022052600530](https://openairdocs.org/sdr/YV3R2022052600530.md): None · defective · May 17, 2022 · Robsin R44RAVENII · Tail Rotor Gearbox
  > CUSTOMER REPORTED TAIL ROTOR GEARBOX ASSEMBLY P/N: C021-1 LEAKED FROM THE INPUT CARTRIDGE SEAL.
- [SDR YV3R2022050400526](https://openairdocs.org/sdr/YV3R2022050400526.md): None · defective · Apr 21, 2022 · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2 WAS UNSERVICEABLE.
- [SDR YV3R2022050400525](https://openairdocs.org/sdr/YV3R2022050400525.md): None · defective · Apr 9, 2022 · N2444 · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER ASSEMBLY P/N: C792-4 NEEDLES WERE JUMPING WITHIN UNIT.
- [SDR 2022FA0000524](https://openairdocs.org/sdr/2022FA0000524.md): Exhaust Valve · broken · Apr 8, 2022 · N911TM · Robsin R44RAVENII · Fuselage Structure (General)
  > DURING CRUISE FLIGHT PILOT REPORTED ENGINE BEGAN TO RUN ROUGH AND MANIFOLD PRESSURE INCREASED. HELICOPTER RETURNED TO HELIPAD AND MADE A NORMAL LANDING. EXHAUST VALVE STEM BROKE AT BELL CURVE AND WAS RELEASED INTO CYLINDER.
- [SDR YV3R2022030400521](https://openairdocs.org/sdr/YV3R2022030400521.md): None · none · Feb 28, 2022 · Robsin R44RAVENII · Engine Cooling System
  > CUSTOMER REPORTED COVER ASSEMBLY (COOLING PANEL) P/N: D382-4 WAS CRACKED.
- [SDR YV3R2022030400520](https://openairdocs.org/sdr/YV3R2022030400520.md): None · none · Feb 16, 2022 · Robsin R44RAVENII · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-2 COLUMN SPRINGS DID NOT ACTUATE SIMULTANEOUSLY.
- [SDR YV3R2022031000522](https://openairdocs.org/sdr/YV3R2022031000522.md): None · defective · Feb 16, 2022 · Robsin R44RAVENII · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-2 WAS INOPERATIVE.
- [SDR YV3R2022050400524](https://openairdocs.org/sdr/YV3R2022050400524.md): None · defective · Feb 14, 2022 · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED WARNING UNIT ASSEMBLY P/N: A569-9 FAILED TO REACT TO RPM'S.
- [SDR YV3R2022011000507](https://openairdocs.org/sdr/YV3R2022011000507.md): None · none · Dec 14, 2021 · N329JK · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2 OCCASIONALLY ROLLED OFF WHEN COLD.
- [SDR YV3R2022011000505](https://openairdocs.org/sdr/YV3R2022011000505.md): None · none · Nov 30, 2021 · Robsin R44RAVENII · Engine RPM Indicating System
  > DURING MAINTENANCE GROUND RUN, GOVERNOR CONTROLLER P/N: D278-2 INDICATED HIGH RPM WITH INDICATOR NEEDLE ON THE RED ARC.
- [SDR YV3R2021112000503](https://openairdocs.org/sdr/YV3R2021112000503.md): None · none · Nov 10, 2021 · Robsin R44RAVENII · Main Rotor Drive System
  > CUSTOMER REPORTED ACTUATOR ASSEMBLY P/N: C051-2 COLUMN SPRINGS FAILED TO ACTUATE MICRO SWITCH.
- [SDR YV3R2021110900499](https://openairdocs.org/sdr/YV3R2021110900499.md): None · none · Oct 1, 2021 · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2, ENGINE INDICATION HIGH AND UNABLE TO ADJUST.
- [SDR YV3R2021100700496](https://openairdocs.org/sdr/YV3R2021100700496.md): None · defective · Sep 22, 2021 · Robsin R44RAVENII · Engine RPM Indicating System
  > CUSTOMER REPORTED CONTROLLER ASSEMBLY P/N: D278-2 WILL NOT MAINTAIN RPM.
- [SDR YV3R2021072200471](https://openairdocs.org/sdr/YV3R2021072200471.md): Warning Unit · defective · Jul 12, 2021 · N882GD · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED WARNING UNIT P/N: A569-9 HORN (AUDIO) DID NOT SOUND.
- [SDR YV3R2021072200470](https://openairdocs.org/sdr/YV3R2021072200470.md): Strut · leaking · Jul 8, 2021 · Robsin R44RAVENII · Main Landing Gear Strut/Axle/Truck
  > CUSTOMER REPORTED CYLINDER ASSEMBLY P/N: D679-3 WAS LEAKING. UPON TROUBLESHOOTING, GAUGE P/N: D769-1 WAS FOUND LEAKING.
- [SDR YV3R2021070700469](https://openairdocs.org/sdr/YV3R2021070700469.md): Dual Tachometer · defective · Jun 30, 2021 · N144KD · Robsin R44RAVENII · Main Rotor Indicating System
  > CUSTOMER REPORTED DUAL TACHOMETER P/N: C792-4 ROTOR NEEDLE READS LOW 2-5%.

Next page: https://openairdocs.org/engine/lycoming-io-540-ae1a5/reports.md?page=2

## The whole list in SQL

Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS:

```sql
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 engine_model_key = 'IO540AE1A5'
ORDER BY difficulty_date DESC
```

This list as a web page: https://openairdocs.org/engine/lycoming-io-540-ae1a5/reports

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