# Lycoming TIO-540-U2A - Type: Engine model (FAA registry) - Registry code: 41990 - Manufacturer (registry): LYCOMING - Model: TIO-540-U2A - Engine type: Reciprocating - Power: 350 hp - Data sheet: [TCDS E14EA](https://openairdocs.org/tcds/E14EA) (OpenAirDocs) - Holder: Lycoming Engines - Installed in: 3 registered aircraft - Page: https://openairdocs.org/engine/lycoming-tio-540-u2a 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 2022-16-03](https://openairdocs.org/ad/2022-16-03): Engine (RECIPROCATING) · Continental Aerospace Technologies GTSIO-520-C, GTSIO-520-D, GTSIO-520-F and 236 more. Effective Aug 15, 2022 - [AD 2015-19-07](https://openairdocs.org/ad/2015-19-07): Fuel injector fuel lines · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1B and 187 more. Effective Nov 3, 2015 - [AD 2012-19-01](https://openairdocs.org/ad/2012-19-01): Crankshafts · Lycoming Engines AEIO-360-A1A, AEIO-360-A1B, AEIO-360-A1B6 and 321 more. Effective Oct 24, 2012 - [AD 2012-03-06](https://openairdocs.org/ad/2012-03-06): Fuel servo diaphragm · Continental Motors 6-260-A, 6-285-A, 6-285-B and 482 more. Effective Feb 24, 2012 - [AD 2010-07-08](https://openairdocs.org/ad/2010-07-08): Turbochargers · Kelly Aerospace Energy Systems HIO-360-E1AD, HIO-360-E1BD, HIO-360-F1AD and 137 more. Effective Apr 19, 2010 - [AD 2009-02-03](https://openairdocs.org/ad/2009-02-03): Fuel injection servos · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 261 more. Effective Feb 9, 2009 - [AD 2005-12-06](https://openairdocs.org/ad/2005-12-06): Riveted-impulse coupling assemblies and snap-ring coupling assemblies · Lycoming Engines AEIO-540-D4A5, AEIO-540-D4B5, AEIO-540-D4C5 and 154 more. Effective Jul 19, 2005 - [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 2004-05-24](https://openairdocs.org/ad/2004-05-24): Zinc-plated Crankshaft Gear Retaining Bolts · Lycoming Engines AEIO-540-D4A5, AEIO-540-D4B5, AEIO-540-D4C5 and 161 more. Effective Mar 30, 2004 - [AD 2003-14-03](https://openairdocs.org/ad/2003-14-03): Rotary fuel pumps · Lycoming Engines AEIO-540-D4A5, AEIO-540-D4B5, AEIO-540-D4C5 and 262 more. Effective Aug 14, 2003 - [AD 2002-19-03](https://openairdocs.org/ad/2002-19-03): Crankshaft · Lycoming Engines IO-540-A1A5, IO-540-AA1A5, IO-540-AA1B5 and 81 more. Effective Sep 20, 2002 - [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 91-08-07](https://openairdocs.org/ad/91-08-07): Fuel Pump · Lycoming Engines TIO-360-A1A, TIO-360-A1B, TIO-360-A3B6 and 51 more. Effective May 6, 1991 - [AD 83-22-04](https://openairdocs.org/ad/83-22-04): Injector Fuel Diaphragm Stem · Lycoming Engines AEIO-540-L1B5D, IO-540-AA1A5, IO-540-G1B5 and 30 more. Effective Nov 4, 1983 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 - [AD 2011-26-04](https://openairdocs.org/ad/2011-26-04) (historical): Externally mounted fuel injector fuel lines · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1B and 186 more. Effective Jan 25, 2012 - [AD 2011-15-10](https://openairdocs.org/ad/2011-15-10) (historical): Fuel servos · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 256 more. Effective Aug 16, 2011 - [AD 2008-14-07](https://openairdocs.org/ad/2008-14-07) (historical): Externally mounted fuel injector fuel lines · Textron Lycoming, AVCO AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1B and 185 more. Effective Aug 14, 2008 - [AD 2008-08-14](https://openairdocs.org/ad/2008-08-14) (historical): Fuel injection servo plugs · Superior Air Parts AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 242 more. Effective Apr 29, 2008 - [AD 2008-06-51](https://openairdocs.org/ad/2008-06-51) (historical): Fuel injection servo plugs · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 235 more - [AD 2006-20-09](https://openairdocs.org/ad/2006-20-09) (historical): Certain crankshafts replacing · Lycoming Engines AEIO-360-A1B6, AEIO-360-A1E6, AEIO-540-D4A5 and 82 more. Effective Nov 3, 2006 - [AD 2005-26-10](https://openairdocs.org/ad/2005-26-10) (historical): ECi cylinder assemblies. · Lycoming Engines AEIO-320-D1B, AEIO-320-D2B, AEIO-320-E1A and 413 more. Effective Jan 31, 2006 - [AD 2002-26-01](https://openairdocs.org/ad/2002-26-01) (historical): Fuel injector fuel lines · Textron Lycoming, AVCO IGO-480-A1B6, IGO-540-B1A, IGO-540-B1C and 178 more. Effective Jan 31, 2003 - [AD 2002-23-06](https://openairdocs.org/ad/2002-23-06) (historical): Crankshaft gear retaining bolts · Textron Lycoming, AVCO AEIO-540, AEIO-540-D4A5, AEIO-540-D4B5 and 46 more. Effective Nov 19, 2002 - [AD 2002-20-51](https://openairdocs.org/ad/2002-20-51) (historical): Crankshaft gear retaining bolts · Textron Lycoming, AVCO AEIO-540, IO-540 Series (all), LTIO-540-F2BD and 39 more - [AD 2002-17-53](https://openairdocs.org/ad/2002-17-53) (historical): Crankshaft · Lycoming Engines LTIO-540-F2BD, LTIO-540-J2B, LTIO-540-J2BD and 36 more - [AD 2002-04-51](https://openairdocs.org/ad/2002-04-51) (historical): Crankshaft · Lycoming Engines LTIO-540-F2BD, LTIO-540-J2B, LTIO-540-J2BD and 8 more - [AD 98-18-12](https://openairdocs.org/ad/98-18-12) (historical): Fuel Pump · Textron Lycoming, AVCO AEIO-540-D4A5, AEIO-540-D4B5, AEIO-540-D4C5 and 249 more. Effective Sep 28, 1998 ## Information bulletins (advisory) (6) - [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-08-32R1](https://openairdocs.org/saib/NE-08-32R1): Propeller Governor Idler Gear Shaft Set Screw. Issued May 13, 2016 - [SAIB NE-14-13](https://openairdocs.org/saib/NE-14-13): Reciprocating Engine - Cylinder Mounting Studs. Issued Mar 24, 2014 - [SAIB NE-09-04](https://openairdocs.org/saib/NE-09-04): Fuel Control/Reciprocating Engines. Issued Jan 10, 2009 - [SAIB NE-06-32R1](https://openairdocs.org/saib/NE-06-32R1): Reciprocating Engine - Crankshaft. Issued Sep 10, 2008 - [SAIB NE-08-32](https://openairdocs.org/saib/NE-08-32) (historical): Propeller Governor Set Screw. Issued Jul 3, 2008 ## Registered aircraft (3) - [N201WF](https://openairdocs.org/aircraft/N201WF): [Sky West Aviation Inc Trustee](https://openairdocs.org/faa-owner/SKY%20WEST%20AVIATION%20INC%20TRUSTEE), [Albuquerque, NM](https://openairdocs.org/faa-place/NM/Albuquerque), built 1984, S/N 608423010 - [N696ME](https://openairdocs.org/aircraft/N696ME): [Bgdr LLC](https://openairdocs.org/faa-owner/BGDR%20LLC), [Wilmington, DE](https://openairdocs.org/faa-place/DE/Wilmington), S/N 61P-0209-020 - [N824MZ](https://openairdocs.org/aircraft/N824MZ): [Maritz Paul](https://openairdocs.org/faa-owner/MARITZ%20PAUL), [Mercer Island, WA](https://openairdocs.org/faa-place/WA/Mercer%20Island), built 1981, S/N 61P08518163449 ## NTSB investigations None matched to aircraft with this engine model. ## FAA accident and incident reports (1) 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. - [Incident 20170416006379I](https://openairdocs.org/incident/20170416006379I), Apr 16, 2017: Piper AEROSTAR 601P (N824MZ), Everett, WA, Minor damage. On 4/16/2017 around 1500 local N824MZ took off from bfi. Shortly after take off the pilot noticed his auto pilot failed, and the rest of his avionics continued… ## Service difficulty reports (8) As reported by operators and repair stations, by the model named in the report. - [SDR 2012FA0000302](https://openairdocs.org/sdr/2012FA0000302), Mar 27, 2012: VALVE SPRING. BROKEN. NOTICED MANIFOLD PRESSURE SPLITS ON LEFT ENGINE, AND A COLD RUNNING NR 3 CYLINDER, INSPECTED AND FOUND INNER AND OUTER EXHAUST VALVE SPRINGS BROKEN. REPLACED BO - [SDR 2012FA0000303](https://openairdocs.org/sdr/2012FA0000303), Mar 27, 2012: VALVE SPRING. BROKEN. LT ENGINE, AFTER NOTICING MANIFOLD PRESSURE SPLITS, AND A COLD RUNING NR 3 CYLINDER, INSPECTED AND FOUND INNER AND OUTER EXHAUST VALVE SPRINGS BROKEN. REPLACED - [SDR CA101122016](https://openairdocs.org/sdr/CA101122016), Nov 18, 2010: BELLOWS. DETACHED. (CAN) DURING CRUISE FLIGHT, RT ENGINE LOST POWER. PILOT ELECTED TO RETURN TO AIRPORT OF DEPARTURE (WINDSOR AIRPORT). PILOT CONDUCTED A POST FLIGHT RUN UP AND ON - [SDR 2005FA0001295](https://openairdocs.org/sdr/2005FA0001295), Sep 9, 2005: VALVE GUIDE. BURNED. DURING ANNUAL INSPECTION, IT WAS DISCOVERED DURING A DIFFERENTIAL COMPRESSION CHECK THAT NR 1CYLINDER ON THIS ENGINE HAD ALMOST NO COMPRESSION. THE CYLINDER WAS - [SDR 2005FA0001296](https://openairdocs.org/sdr/2005FA0001296), Sep 9, 2005: VALVE GUIDE. BURNED. DURING ANNUAL INSPECTION, IT WAS DISCOVERED DURING A DIFFERENTIAL COMPRESSION CHECK THAT THE NR 1 CYLINDER ON THIS ENGINE HAD ALMOST NO COMPRESSION. THE CYLINDE - [SDR 021081](https://openairdocs.org/sdr/021081), Jan 9, 2003: CRANKCASE. CRACKED. ON 28 DEC 2002, AEROSTAR N6902T LANDED AT OAJ WITH NR 2 (RT) ENGINE SHUTDOWN AND PROPELLERS FEATHERED. THE PILOT STATED THAT DURING FLIGHT, HE NOTICED A DROP IN - [SDR 97ZZZX3789](https://openairdocs.org/sdr/97ZZZX3789), May 15, 1997: WASHER. WORN. DURING C/W SB 600-131, SUBSTANTIATED BOTH SCAVANGE OIL PUMPS WERE DUE IMMINENT FAILURE. REPLACED PARTS REQUIRED. - [SDR 95ZZZX774](https://openairdocs.org/sdr/95ZZZX774), Feb 8, 1995: TURBOCHARGER. OIL LEAK. DURING ANNUAL INSPECTION, CENTER SECTION OF TURBO LEAKING OIL. REMOVED FITTINGS, FOUND SEVERAL CHUNKS OF METAL INSIDE CENTER SECTION. NO EVIDENCE OF METAL CONTA ## STCs that may be installed (OpenAirDocs) (29) 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 SE00825WI](https://openairdocs.org/stc/SE00825WI): Installation of Specialty Products Spin-on oil filter on Lycoming Engines. B & C Specialty Products Inc - [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 SE02352CH](https://openairdocs.org/stc/SE02352CH): Installation of Challenger cleanable oil filter assembly. Challenger Aviation Products Inc - [STC SE00939WI](https://openairdocs.org/stc/SE00939WI): Installation of B&C Specialty Products Model BC 315-( ) Starter on Lycoming engines. B & C Specialty Products Inc - [STC SE2667CE](https://openairdocs.org/stc/SE2667CE): Installation of B&C Specialty Products lightweight (10.2 pounds) engine starter PN BC315-100-2(12 volt) or PN BC315-100-4 (24 volt). B & C Specialty Products Inc - [STC SE03309CH](https://openairdocs.org/stc/SE03309CH): Installation of Engine Preheat Kit, p/n TSP6CYL-2927-115 for 115 volt application. Hartzell Propeller Inc - [STC SE01436LA](https://openairdocs.org/stc/SE01436LA): Installation of Firewall Forward Technologies LLC modified camshaft. Centri-lube Technologies LLC - [STC SE04577CH](https://openairdocs.org/stc/SE04577CH): Install an electronic engine ignition system. Electroair Acquisition Corp - [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 SE09445SC](https://openairdocs.org/stc/SE09445SC): Installation of fuel injector nozzles. General Aviation Modifications Inc. Lists TIO-540 Series - [STC SE7503SW](https://openairdocs.org/stc/SE7503SW): Installation of any or all parts listed on Airmotive Engineering Drawing List No. 852-1, Rev. 1, dated 10/4/88, or later FAA approved revision. Continental Motors, Inc. Lists TIO-540 Series - [STC SE7668SW](https://openairdocs.org/stc/SE7668SW): Installation of parts listed on Drawing List 8810-3, Rev 6. Continental Motors, Inc. Lists TIO-540 Series - [STC SE8776SW](https://openairdocs.org/stc/SE8776SW): Installation of coated cylinders and piston rings. Continental Motors, Inc. Lists TIO-540 Series - [STC SE00226NY](https://openairdocs.org/stc/SE00226NY): Replacement of Lycoming starter with SKY-TEC 24-volt starter Models 149-24HT and 122-24HT. Approval limited to 24-volt DC source available to the starter. Hartzell Engine Technologies, LLC - [STC SE02436AT](https://openairdocs.org/stc/SE02436AT): Installation of 200F series fuel pump assembly. Kelly Aerospace Energy Systems LLC - [STC SE01930NY](https://openairdocs.org/stc/SE01930NY): Installation of Casper Labs 90 degree oil filter housing adapter. Casper Labs Inc - [STC SE1779NM](https://openairdocs.org/stc/SE1779NM): Installation of Precise Flight, Inc. Standby Vacuum System SVS III. Precise Flight Inc - [STC SE5743NM](https://openairdocs.org/stc/SE5743NM): Intallation of adapter for externally mounted oil filter. Aviation Development Corporation - [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 TIO-540 Series - [STC SE00350SE](https://openairdocs.org/stc/SE00350SE): Installation of sump mounted chip detector. Aviation Development Corporation - [STC SE7674SW](https://openairdocs.org/stc/SE7674SW): Grind nitrided cylinder barrels plus .010 over size pistons, to .010 and install SL10545P10 SL74241P10 compression rings and SL73857P10 Oil Control rings. Superior Air Parts, Inc - [STC SE8023SW](https://openairdocs.org/stc/SE8023SW): Installation and usage of AEROSHELL. Shell Development Co. Lists TIO-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 TIO-540 Series - [STC SE244NE](https://openairdocs.org/stc/SE244NE): Installation of Mattituck plasma flame sprayed cylinder barrels in Teledyne reciprocating engines. Mattituck Airbase, Inc. Lists TIO-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 TIO-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 TIO-540 Series - [STC SA01436DE](https://openairdocs.org/stc/SA01436DE) (historical): Installation of Firewall Forward Technologies, LLC modified camshaft. Centri-Lube Technologies LLC --- 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.