# Lycoming O-540

The Lycoming O-540 is a family of air-cooled six-cylinder, horizontally opposed fixed-wing aircraft and helicopter engines of 541.5 cubic inches (8.9 L) displacement, manufactured by Lycoming Engines. The engine is a six-cylinder version of the four-cylinder Lycoming O-360.

## Design and development

Producing between 230 and 350 horsepower (170 and 260 kW) these engines are installed in a large variety of aircraft. The main competitors are the Continental IO-520 and IO-550 series.
An AEIO version was developed for high-performance competition aerobatics aircraft. Starting at 260 hp (190 kW) the power was eventually increased to 300 hp (220 kW). The AEIO-540 family has achieved considerable success in aircraft such as the Extra 300, CAP 232, and Zivko Edge 540.

## Variants

All engines have an additional prefix preceding the 540 to indicate the specific configuration of the engine. The numerous engine suffixes denote different accessories such as different manufacturers' carburetors, or different magnetos.

### O-540

    Standard, direct-drive, normally aspirated Opposed engine, equipped with a carburetor

### IO-540

    Normally aspirated engine with continuous fuel Injection

### AEIO-540

    Normally aspirated engine with fuel injection and inverted lubrication for Aerobatic use

### TIO-540

    Turbocharged and fuel-injected

### TEO-540

    Turbocharged with a FADEC control system using Lycoming's iE2 system, offering independent Electronic sensors and fuel injection controls for each cylinder, which manage detonation and exhaust gas temperature, make the engine compatible with a range of fuel compositions, producing up to 375 hp (280 kW).

### LTIO-540

    Left-hand (opposite-direction) rotation, turbocharged, fuel-injected; used as the right-hand engine on Piper PA-31-325 Navajo C/Rs and Piper PA-31-350 Chieftain|Piper Mojaves to prevent critical engine control issues, and used for the left side of the Aerostar 700P

### IGO-540

    Gearbox at the front end of the crankshaft to drive the propeller at fewer revolutions per minute than the engine, normally aspirated with fuel injection, dry sump engine built specifically for the Aero Commander 560F

### TIGO-540

    Turbo-charged, injected and geared

### IGSO-540

    Supercharger driven by the engine, gearbox to drive propeller, and fuel injection (up to 380 hp (280 kW))

### VO-540

    Vertically mounted engine for use in a helicopter, normally aspirated and equipped with a carburetor

### IVO-540

    Normally aspirated engine with fuel injection, mounted vertically for use in a helicopter

### TVO-540

    Turbocharged engine equipped with a carburetor, mounted vertically for use in a helicopter

### TIVO-540

    Turbocharged engine with fuel injection, mounted vertically for use in a helicopter

### HIO-540

    Helicopter engine mounted horizontally as in fixed-wing aircraft, normally aspirated with fuel injection; not used in any fixed-wing aircraft

### TIO-541

    Same as a TIO-540, except the "1" indicates an integral accessory drive

### TIGO-541

    Same as a TIGO-540, except the "1" indicates an integral accessory drive

## Applications

* AAC Angel
* Aero Commander 500 series
* AeroVolga LA-8L
* Akaflieg München Mü30 Schlacro
* Bárcenas B-01
* Barrows Bearhawk
* Bede BD-3
* Beechcraft Bonanza (by aftermarket STC)
* Bearhawk 5
* Bellanca Viking 300 (17-31 and 17-31TC)
* Bellanca 17-31ATC Turbo Viking
* Britten-Norman Islander
* Britten-Norman Trislander
* Brantly 305
* CallAir A-9
* Celair Eagle 300
* Cerva CE.43 Guépard
* Cessna 182
* Cessna 206
* Dornier Do 28
* Dream Tundra
* Edgley Optica
* Embraer EMB 202 Ipanema
* Enaer T-35 Pillan
* Evangel 4500
* Express Series 90
* Extra EA-260
* Extra EA-300
* Gippsland GA8
* Gippsland GA200
* Grob 120
* HAL HPT-32 Deepak
* Hiller UH-12
* IAR-823
* Lancair ES
* Lake Aircraft
* Lasta 95
* Helio/Maule M5-235
* Mooney M20
* Moynet 360-6 Jupiter
* MSW Votec 252T
* Murphy Moose
* Neiva Universal
* Northrop Grumman Firebird
* PAC CT/4E / CT/4F Airtrainer
* PAC Super Mushshak
* PAF XT-001 Marko 1
* Performance Aircraft Formula GT
* Piaggio P.166
* Piper Aerostar
* Piper Aztec
* Piper Saratoga
* Piper PA-24 Comanche
* Piper PA-25 Pawnee
* Piper PA-28 Cherokee 235
* Piper PA-31 Navajo
* Piper PA-32 Cherokee Six
* Pipistrel Panthera
* Piper PA-46 Mirage
* Pitts Special
* PZL M26 Iskierka
* PZL-104MA Wilga 2000
* Raven 2XS
* Ravin 500
* Rihn DR-109
* Robinson R44
* Rockwell Commander 114
* Ruschmeyer R 90-230-FG
* Sharp Nemesis NXT
* SIAI-Marchetti SF.260
* SkyDancer SD-260
* Socata TB-20
* Socata TB-30 Epsilon
* Starfire Firebolt
* Stoddard-Hamilton Glasair III
* Swearingen SX-300
* Team Tango Foxtrot
* Team Rocket F1 Rocket
* Tecnam P2012 Traveller
* Ultimate 10-300
* Utva 65
* Van's Aircraft RV-10
* Velocity XL
* Washington T-411 Wolverine
* Wilson Global Explorer
* Zlin Z-143
* Zlín Z 50

## Specifications (IO-540-K1A5)

Data from FAA Lycoming IO-540 Series Type Certificate. Retrieved: 1 September 2008.

### General characteristics

* Type: Six-cylinder air-cooled horizontally opposed engine
* Bore: 5.125 in (130.2 mm)
* Stroke: 4.375 in (111.1 mm)
* Displacement: 541.5 in³ (8.9 L)
* Dry weight: 438 lb (199 kg)

### Components

* Valvetrain: Two overhead valves per cylinder
* Fuel system: Fuel injection
* Fuel type: 100 octane rating gasoline
* Cooling system: Air-cooled

### Performance

* Power output: 300 hp (220 kW) at 2,700 rpm at sea level
* Specific power: 0.55 hp/in³ (25.14 kW/L)
* Compression ratio: 8.7:1
* Power-to-weight ratio: 0.68 hp/lb (1.12 kW/kg)