# Lycoming VO-540-C2A - Type: Engine model (FAA registry) - Registry code: 42244 - Manufacturer (registry): LYCOMING - Model: VO-540-C2A - Engine type: Reciprocating - Power: 315 hp - Data sheet: [TCDS E-304](https://openairdocs.org/tcds/E-304) (OpenAirDocs) - Holder: Lycoming Engines - Installed in: 6 registered aircraft - Page: https://openairdocs.org/engine/lycoming-vo-540-c2a Model codes come from the FAA registry's reference file. ## ADs that may apply (OpenAirDocs) Matched to this engine model by model name and maker. Each AD's applicability may narrow it by serial number, part number or equipment. - [AD 2026-04-11](https://openairdocs.org/ad/2026-04-11): Engine (Reciprocating) · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 605 more. Effective Apr 8, 2026 - [AD 2012-03-07](https://openairdocs.org/ad/2012-03-07): Carburetor · Lycoming Engines GO-435, GO-435-C2 (O-435-17), GO-435-C2A and 389 more. Effective Mar 27, 2012 - [AD 2004-10-14](https://openairdocs.org/ad/2004-10-14): Crankshaft gear · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 642 more. Effective Jun 25, 2004 - [AD 97-15-11](https://openairdocs.org/ad/97-15-11): Cylinder kits · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 538 more. Effective Aug 12, 1997 - [AD 92-12-05](https://openairdocs.org/ad/92-12-05): Piston Pins · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 532 more. Effective Jul 10, 1992 - [AD 89-04-02](https://openairdocs.org/ad/89-04-02): Carburetors · Continental Motors O-470-11, O-470-11-CI, O-470-11B and 175 more. Effective Mar 8, 1989 - [AD 80-04-04 R1](https://openairdocs.org/ad/80-04-04-R1): Crankshaft Flange Bolts · Lycoming Engines IVO-540-A1A, TIVO-540-A2A, TVO-435-A1A and 38 more. Effective Aug 18, 1980 - [AD 73-23-01](https://openairdocs.org/ad/73-23-01): Piston Pin Assembly · Lycoming Engines AIO-360-A1A, AIO-360-A1B, AIO-360-A2A and 215 more. Effective Jan 13, 1977 - [AD 73-05-01](https://openairdocs.org/ad/73-05-01): Connecting Rod Bearing Assemblies · Lycoming Engines IVO-540-A1A, TIVO-540-A2A, TVO-540-A1A and 21 more. Effective Jul 9, 1974 - [AD 69-24-03](https://openairdocs.org/ad/69-24-03): Carburetors · Continental Motors A-65-1, A-65-12, A-65-12F and 321 more. Effective Nov 29, 1969 - [AD 66-06-03](https://openairdocs.org/ad/66-06-03): Connecting Rod Assemblies · Lycoming Engines GO-435-C2 (O-435-17), GO-435-C2A, GO-435-C2A2 and 317 more. Effective Jan 16, 1969 - [AD 68-08-08](https://openairdocs.org/ad/68-08-08): Hydraulic Valve · Lycoming Engines IGSO-480-A1A6, IGSO-480-A1B6, IGSO-480-A1C6 and 44 more. Effective May 19, 1968 Historical (superseded or no longer in force): - [AD 2024-21-02](https://openairdocs.org/ad/2024-21-02) (historical): Engine (Reciprocating) · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 548 more. Effective Dec 5, 2024 ## Information bulletins (advisory) (2) - [SAIB NE-19-08](https://openairdocs.org/saib/NE-19-08): Reciprocating Engine Cylinder Section - Lycoming Engines Parallel Valve Cylinders. Issued May 2, 2019 - [SAIB NE-14-13](https://openairdocs.org/saib/NE-14-13): Reciprocating Engine - Cylinder Mounting Studs. Issued Mar 24, 2014 ## Registered aircraft (6) - [N16NR](https://openairdocs.org/aircraft/N16NR): [Paragon Helicopter Services LLC](https://openairdocs.org/faa-owner/PARAGON%20HELICOPTER%20SERVICES%20LLC), [Claremore, OK](https://openairdocs.org/faa-place/OK/Claremore), built 1964, S/N 1755 - [N22SP](https://openairdocs.org/aircraft/N22SP): [Paragon Helicopter Services LLC](https://openairdocs.org/faa-owner/PARAGON%20HELICOPTER%20SERVICES%20LLC), [Claremore, OK](https://openairdocs.org/faa-place/OK/Claremore), built 1959, S/N 1214 - [N875WE](https://openairdocs.org/aircraft/N875WE): [Eastern Stearman Inc Trustee](https://openairdocs.org/faa-owner/EASTERN%20STEARMAN%20INC%20TRUSTEE), [Leesburg, VA](https://openairdocs.org/faa-place/VA/Leesburg), S/N 5183 - [N90457](https://openairdocs.org/aircraft/N90457): [Hiller Aviation Group Inc](https://openairdocs.org/faa-owner/HILLER%20AVIATION%20GROUP%20INC), [Laveen, AZ](https://openairdocs.org/faa-place/AZ/Laveen), S/N 2507 - [N922HA](https://openairdocs.org/aircraft/N922HA): [Hiller Aviation Group Inc](https://openairdocs.org/faa-owner/HILLER%20AVIATION%20GROUP%20INC), [Laveen, AZ](https://openairdocs.org/faa-place/AZ/Laveen), S/N 5015 - [N9737C](https://openairdocs.org/aircraft/N9737C): [M&D Aerial LLC](https://openairdocs.org/faa-owner/M%26D%20AERIAL%20LLC), [Coleman, TX](https://openairdocs.org/faa-place/TX/Coleman), built 1962, S/N 2163 ## NTSB investigations (4) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB CEN26LA175](https://openairdocs.org/ntsb/CEN26LA175), Apr 30, 2026: Hiller UH-12E (N22SP), Chickasha, OK, substantial damage, investigation ongoing - [NTSB CHI88DER06](https://openairdocs.org/ntsb/CHI88DER06), Jul 30, 1988: Hiller UH-12E (N173HA), Buffalo Lake, MN, destroyed - [NTSB MKC83LA207](https://openairdocs.org/ntsb/MKC83LA207), Aug 31, 1983: Hiller UH-12E (N173HA), Corwith, IA, destroyed - [NTSB DEN67A0071](https://openairdocs.org/ntsb/DEN67A0071), May 23, 1967: Hiller UH-12L (N90457), Fairplay, CO, substantial damage ## FAA accident and incident reports (3) From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [Accident 20260430003599A](https://openairdocs.org/incident/20260430003599A), Apr 30, 2026: Hiller UH-12E (N22SP), Chickasha, OK, Substantial damage. On April 30, 2026, at approximately 1730 a [privacy data omitted] helicopter was traversing between fields where it was spraying agricultural products, when… - [Accident 19880730028379A](https://openairdocs.org/incident/19880730028379A), Jul 30, 1988: Hiller UH12E (N173HA), Buffalo Lake, MN, Destroyed. Tail rotor control cable broke during vertical takeoff from truck platform. Cables frayed and worn. Acft destroyed. - [Accident 19830831045439A](https://openairdocs.org/incident/19830831045439A), Aug 31, 1983: Hiller UH12E (N173HA), Corwith, IA, Destroyed. Helicopter crashed during autorotation landing after failure in main rotor control system. ## Service difficulty reports (22) As reported by operators and repair stations, by the model named in the report. - [SDR CA120605011](https://openairdocs.org/sdr/CA120605011), May 29, 2012: CROSSTUBE. BROKEN. (CAN) FWD CROSSTUBE WAS FOUND BROKEN AT THE LT SIDE INBD BOLT HOLE UPON INSPECTION AFTER BEING TRAILERED TO A JOB SITE. - [SDR CA090220003](https://openairdocs.org/sdr/CA090220003), Feb 20, 2009: SPAR. CRACKED. (CAN) DURING INSP IAW AWD 97-10-16 (A) CONTROL ROTOR PN 36209-3, SN 449. FOUND CRACKED AT LOWER BOLT HOLE .600 FROM END OF SPAR. - [SDR 2006FA0000427](https://openairdocs.org/sdr/2006FA0000427), Apr 12, 2006: HUB. CRACKED. M/R HUB DYE CHECK INSPECTION. HUB WAS FOUND TO BE CRACKED. RETIREMENT LIFE, 2500 HOURS. (K) - [SDR AUS20030449](https://openairdocs.org/sdr/AUS20030449), Apr 9, 2003: CONTROL CABLE. FAILED. (AUS) TAIL ROTOR CONTROL CABLE FAILED. CABLE RUNS FROM RT PEDAL TO FIREWALL LOCATED BEHIND THE PILOT SEAT. CABLE HAD BEEN SUBJECTEDTO HEAT SOURCE, POSSIBLY CONT - [SDR AUS20020789](https://openairdocs.org/sdr/AUS20020789), Jun 14, 2002: SCREW. FAILED. (AUS) ENGINE ACCESSORY DRIVE GEAR PNO 67609 TO STARTER DRIVE GEAR PNO 67583 ATTACHMENT STUDS (6OFF) PNO STD-2208 AND DOWELS (3OFF) PNO72139 SHEARED. - [SDR AUS20010648](https://openairdocs.org/sdr/AUS20010648), May 31, 2001: GEAR. FAILED. (AUS) ENGINE DRIVE GEAR PNO 67583 HAD SHEARED ALL THE BOLTS ATTACHING IT TO ACCESSORY DRIVE PNO 67609. - [SDR AU001151](https://openairdocs.org/sdr/AU001151), Dec 5, 2000: HUB. CRACKED. (AUS) MAIN ROTOR HUB SEVERELY CRACKED IN AN AREA NOT KNOWN FOR CRACKING. FOLLOWING TAKEOFF CONTROL WAS ALMOST IMPOSSIBLE AND THE MASSIVE VIBRATION CAUSED THE FO - [SDR AU971422](https://openairdocs.org/sdr/AU971422), Nov 7, 1997: PIN. CRACKED. (AUS) MAIN ROTOR HEAD TENSION/TORSION PIN CRACKED. - [SDR 97ZZZX3544](https://openairdocs.org/sdr/97ZZZX3544), Jul 19, 1997: BEARING. MISMANUFACTURED. NEW REPLACEMENT BEARING RECEIVED WITH INSTRUCTIONS FROM MRC (BEARING MFG), AND HILLER SL UH12-25-1 DESCRIBING INSTALLATION INSTRUCTIONS WITH REGARDS TO THE FILI - [SDR AU970991](https://openairdocs.org/sdr/AU970991), Jun 14, 1997: GEAR. DAMAGED. (AUS) MAIN ROTOR TRANSMISSION UPPER PLANETARY RING GEAR TOOTH CHIPPED - MINOR DAMAGE TO ONE UPPER PLANETARY GEAR - [SDR CA970716002](https://openairdocs.org/sdr/CA970716002), Jun 12, 1997: BOLT. SHEARED. (CAN) ENGINE FAILED IN FLIGHT. ON DISASSEMBLY IT WAS FOUND THAT THE CAMSHAFT GEAR SCREWS HAD SHEARED EXCEPT FOR ONE THAT WAS STILL INTACT, BUT LYING IN THE OIL - [SDR AU970531](https://openairdocs.org/sdr/AU970531), May 19, 1997: CRANKCASE. CRACKED. (AUS) ENGINE CRANKCASE CRACKED AND TUNNEL OUT OF LIMITS - CRANKSHAFT WORN BEYOND LIMITS - CAMSHAFT LOBES DAMAGED - [SDR 97ZZZX2037](https://openairdocs.org/sdr/97ZZZX2037), Apr 24, 1997: PISTON PIN. DEFECTIVE. AD 97-01-03 AND LYC SB 527B DO NOT REFERENCE VO540 ENGINES IN MODELS AFFECTED, BUT 4 OF 6 PISTON PINS IN ENGINE HAD TO BE REPLACED IN C/W THE SB REQUIRED ACTION - [SDR 97ZZZX1825](https://openairdocs.org/sdr/97ZZZX1825), Apr 7, 1997: VALVE. FAILED. THE HELICOPTER WAS RUNNING ROUGH SO A COMPRESSION CHECK WAS RUN. THE NR 2 CYLINDER HELD NO COMPRESSION AND WAS REMOVED FOR INSPECTION. NOTED A .1250 INCH BY .25 - [SDR 97ZZZX2838](https://openairdocs.org/sdr/97ZZZX2838), Apr 7, 1997: INTAKE VALVE. WORN. THE VALVE STEM UNDER THE KEEPER'S WAS HEAVILY WORN. THIS CONDITION WAS ALSO FOUND ON 4 OTHER VALVES (INTAKE) ALL HAVING THE SAME TOTAL TIME AND PART NUMBER. THE - [SDR AU970349](https://openairdocs.org/sdr/AU970349), Mar 23, 1997: STUD. BROKEN. (AUS) NO2 CYLINDER HOLD DOWN STUDS BROKEN - INVESTIGATION FOUND SIX CYLINDER BASE NUTS MISSING, THIRTY NUTS LOOSE AND ONLY TWELVE NUTS TO BE TIGHT - CRANKCASE P - [SDR 97ZZZX1133](https://openairdocs.org/sdr/97ZZZX1133), Feb 25, 1997: CYLINDER. NOT TO SPEC. DURING ASSEMBLY OF ENGINE, MEASURED DRY TAPPET CLEARANCE FROM .107 INCH TO .187 INCH. LYC OHM REQUIRES .028 INCH TO .080 INCH. RETURNED 6 CYLINDERS TO EC/SW WHE - [SDR AU960746](https://openairdocs.org/sdr/AU960746), May 26, 1996: CONTROL ROTOR. CRACKED. (AUS) MAIN ROTOR HEAD CONTROL ROTOR CRACKED AT SPAR END THROUGH THE FIRST BOLT HOLE FOR APPROXIMATELY 50% OF CIRCUMFERENCE - FOUND DURING INSPECTION IAW AD/HIL1 - [SDR 96ZZZX2365](https://openairdocs.org/sdr/96ZZZX2365), Apr 15, 1996: CARBURETOR. FLOAT STICKS. INSPECTION FOUND CARBURETOR FLOAT WAS RUBBING ON LOWER HOUSING AND STICKING OPEN. - [SDR 96ZZZX2366](https://openairdocs.org/sdr/96ZZZX2366), Apr 15, 1996: CARBURETOR. FLOAT STICKS. INSPECTION FOUND CARBURETOR FLOAT WAS RUBBING ON LOWER HOUSING AND STICKING OPEN. - [SDR AU960748](https://openairdocs.org/sdr/AU960748), Apr 2, 1996: ROTOR HUB. CRACKED. (AUS) MAIN ROTOR HUB CRACKED IN AREA OF THREADED CUFF AND TRUNNION BOLTHOLE EXTENDING DOWN THE INNER HUB SURFACE - CRACK LENGTH APPROXIMATELY 6.35MM (0.25IN) - - [SDR AU960353](https://openairdocs.org/sdr/AU960353), Feb 25, 1996: HUB. CRACKED. (AUS) MAIN ROTOR HUB CRACKED - FOUND DURING INSPECTION IAW AD/HIL12/22A ## STCs that may be installed (OpenAirDocs) (21) Approved for this engine model: the STC's model list names it on its data sheet, or a series that includes it. In force first, then newest. The registry doesn't record which STCs an aircraft has. - [STC SE2932SW](https://openairdocs.org/stc/SE2932SW): Install carburetor air temperature indicator. Approved for Aircooled Motors (Franklin Engine Co.) equipped with float carburetors. Model eligibility included here may not be inclusive. Alcor LLC. Lists VO-540 Series - [STC SE04349CH](https://openairdocs.org/stc/SE04349CH): Installation of SureFly electronic ignition. SureFly Partners Ltd - [STC SE01954SE](https://openairdocs.org/stc/SE01954SE): Installation of engine crankcase seal. Ly-Con Rebuilding Company - [STC SE01966WI](https://openairdocs.org/stc/SE01966WI): Use of GAMI G100UL High Octane Unleaded Avgas in spark ignition piston aircraft engines. General Aviation Modifications Inc - [STC SE8628SW](https://openairdocs.org/stc/SE8628SW): Installation of oil nozzles for lubrication of cam and filters. Cygnet Aerospace Corp - [STC SE4408SW](https://openairdocs.org/stc/SE4408SW): Miscellaneous engine cylinder replacement parts. Continental Motors, Inc. Lists VO-540 Series - [STC SE8776SW](https://openairdocs.org/stc/SE8776SW): Installation of coated cylinders and piston rings. Continental Motors, Inc. Lists VO-540 Series - [STC SE2902NM](https://openairdocs.org/stc/SE2902NM): Lycoming valve cover gasket. Real Gaskets Tennessee - [STC SE7582SW](https://openairdocs.org/stc/SE7582SW): Grinding of high compression NITRIDED Cylinders to .010 oversize, as an alternative to chrome plating or rebarreling, and the installation of SL10207 P10 Piston, SL74241 P10 Top and second compression ring, and SL 73857 P10 oil control ring. Superior Air Parts, Inc - [STC SE1779NM](https://openairdocs.org/stc/SE1779NM): Installation of Precise Flight, Inc. Standby Vacuum System SVS III. Precise Flight Inc - [STC SE00890LA](https://openairdocs.org/stc/SE00890LA): Installation of Nickson's cylinder barrels on Lycoming reciprocating engine models. Nickson's Machine Shop Inc. Lists VO-540 Series - [STC SE1-201](https://openairdocs.org/stc/SE1-201): Installation of the Richter Aero Equipment Type B-4 or B-5 Temperature Probe. (O-360 SERIES (excl. A1C, C2B, C2D)). MidContinent Instru Co Inc - [STC SE09492SC](https://openairdocs.org/stc/SE09492SC): Installation and usage of Exxon 20W50 multigrade aircraft engine oil conforming to Exxon Oil formulation WS-3013. Exxon Company USA. Lists VO-540 Series - [STC SE00350SE](https://openairdocs.org/stc/SE00350SE): Installation of sump mounted chip detector. Aviation Development Corporation - [STC SE8023SW](https://openairdocs.org/stc/SE8023SW): Installation and usage of AEROSHELL. Shell Development Co. Lists VO-540 Series - [STC SE452NE](https://openairdocs.org/stc/SE452NE): Installation and usage of 'Mobil AV 1' aviation oil. Mobil Research & Development Corp. Lists VO-540 Series - [STC SE5879SW](https://openairdocs.org/stc/SE5879SW): Use of Phillips X/C II 20W-50 and25W-60 oil (OSS 55875) in all Avco reciprocating aircraft engines from 65 to 450 BHP. Phillips Petroleum Co. Lists VO-540 Series - [STC SE5924SW](https://openairdocs.org/stc/SE5924SW): Installation of stainless steel replacement exhaust studs on AVCO engines. Perrigo & Steele Aircraft Engr Company. Lists VO-540 Series - [STC SE80NE](https://openairdocs.org/stc/SE80NE): Installation and usage of Bel-Ray synthetic aviation oil, Bel-Ray Aero 1, (nonsupercharged), horizontally opposed direct drive, aircraft engines of 350 hp. or less. Bel-Ray Company, Inc. Lists VO-540 Series - [STC SE128NE](https://openairdocs.org/stc/SE128NE): Use of AMS/OIL 15W 50 synthetic piston aircraft oil in Avco engines. AMS/OIL. Lists VO-540 Series - [STC SE44WE](https://openairdocs.org/stc/SE44WE): Use of Kling Aviation Oil, Specifications KL-100, KL-200 and KL-300 in Continental and Lycoming engines. Kling Oil Company. Lists VO-540 Series --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.