The Lycoming O-540 is a family of air-cooled six-cylinder,

horizontally opposed A flat engine is a piston engine where the cylinders are located on either side of a central crankshaft. Flat engines are also known as horizontally opposed engines, however this is distinct from the less common opposed-piston engine design, wh ...

fixed-wing aircraft A fixed-wing aircraft is a heavier-than-air flying machine, such as an airplane, which is capable of flight using wings that generate lift caused by the aircraft's forward airspeed and the shape of the wings. Fixed-wing aircraft are distinc ...

and helicopter engines of displacement, manufactured by

Lycoming Engines Lycoming Engines is a major American manufacturer of aircraft engines. With a factory in Williamsport, Pennsylvania, Lycoming produces a line of horizontally opposed, air-cooled, four, six and eight-cylinder engines including the only FAA-certi ...

. The engine is a six-cylinder version of the four-cylinder Lycoming O-360.

Design and development

Producing between these engines are installed in a large variety of aircraft. The main competitors are the

Continental IO-520 The Continental O-520 is a six-cylinder, horizontally opposed aircraft engine produced by Teledyne Continental Motors. First run in 1963 as a development of the IO-346, it has been produced in versions incorporating fuel injection (IO-520), tu ...

and IO-550 series. An AEIO version was developed for high-performance competition aerobatics aircraft. Starting at the power was eventually increased to . The AEIO-540 family has achieved considerable success in aircraft such as the Extra 300,

CAP 232 The CAP Aviation CAP-23x family is a family of aircraft designed for competition aerobatics. The CAP 230 airframe was a direct development of the CAP 21 competition single seater strengthened to cope with a 6-cylinder Lycoming AEIO-540 engine in ...

, 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 A carburetor (also spelled carburettor) is a device used by an internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the venturi tube in the main meteri ...

;IO-540 :Normally aspirated engine with fuel Injection ;AEIO-540 :Normally aspirated engine with fuel injection and inverted lubrication for Aerobatic use ;TIO-540 : Turbocharged and fuel-injected Lycoming TEO540

;TEO-540 : Turbocharged with 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 . LTIO540engine

;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 The Piper PA-31 Navajo is a family of cabin-class, twin-engined aircraft designed and built by Piper Aircraft for the general aviation market, most using Lycoming engines. It was also license-built in a number of Latin American countries. Tar ...

sFAA Piper PA-31-300/325/350 Type Certificate.
Retrieved: 1 September 2008. 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 ) ;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 aircraftPage listing all variants of the Lycoming O-540 series.
Retrieved: 1 September 2008. ;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

Specifications (IO-540-K1A5)

References

External links

540 Series homepage at Lycoming.com
{{Lycoming aeroengines Boxer engines O-540 1950s aircraft piston engines