The Lycoming IO-233 is a non-certified four-cylinder, air-cooled, horizontally opposed piston aircraft engine that produces between and . The IO-233 is a development of the

Lycoming O-235 The Lycoming O-235 is a family of four-cylinder, air-cooled, horizontally opposed, piston aircraft engines that produce , derived from the earlier O-233 engine.Textron Lycoming: ''Operator's Manual, Textron Lycoming Aircraft Engines, Series O-2 ...

, which is itself a derivative of the older Lycoming O-233 engine.

Development

FK-Lightplanes FK12 Comet with Lycoming IO-233 engine

The IO-233 was announced by the company at

AirVenture EAA AirVenture Oshkosh (formerly the EAA Annual Convention and Fly-In), or just Oshkosh, is an annual air show and gathering of aviation enthusiasts held each summer at the Wittman Regional Airport and adjacent Pioneer Airport in Oshkosh, Wiscon ...

on 28 July 2008 as a new engine for

light sport aircraft A light-sport aircraft (LSA), or light sport aircraft, is a category of small, lightweight aircraft that are simple to fly. LSAs tend to be heavier and more sophisticated than ultralight (aka "microlight") aircraft, but LSA restrictions on weigh ...

. The engine was conceived as a lightened version of the

by company engineers who were building their own kit LSAs and found that there was no powerplant that met their requirements for power output and weight, with the ability to burn either 100LL avgas or unleaded automotive fuel. The resulting engine weighs less than the O-235 and incorporates a throttle body injector system with a tuned intake manifold and dual electronic ignition, or optionally a

carburetor A carburetor (also spelled carburettor or carburetter) is a device used by a gasoline 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 Ventu ...

in place of the throttle body injector to save further cost and weight. The engine has a 2400-hour time between overhauls. Additional features include a lightweight 14 volt alternator, an optimized oil sump, a streamlined accessory housing, a lightweight starter and roller tappets. When announced in July 2008 Lycoming expected the engine to be available later that year, once

ASTM ASTM International, formerly known as American Society for Testing and Materials, is a standards organization that develops and publishes voluntary consensus technical international standards for a wide range of materials, products, systems and s ...

testing for LSA use was completed. The company also contemplated certifying the engine in 2009. There is no indication that certification has been completed. At AirVenture 2011, the company announced that the engine was commencing volume production and was flying in both fuel-injected and carbureted versions. Renegade Light Sport's Falcon LS was the first airplane to fly with Lycoming's new IO-233-LSA engine on 6 Oct 2010. Renegade Light Sport is working with Lycoming to produce an

aerobatic Aerobatics is the practice of flying maneuvers involving aircraft attitudes that are not used in conventional passenger-carrying flights. The term is a portmanteau of "aeroplane" and "acrobatics". Aerobatics are performed in aeroplanes and gl ...

version of the IO-233-LSA engine to be designated as the AEIO-233. The design goals include fuel injection, an inverted sump and that it be capable of +9/-3 Gs.

Variants

;IO-233-LSA :Initial version, at 2400

rpm Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or r⋅min−1) is a unit of rotational speed (or rotational frequency) for rotating machines. One revolution per minute is equivalent to hertz. Standards ISO 80000-3:2019 def ...

to at 2800 rpm

Applications

* Aeris Naviter AN-2 Enara *

Dakota Cub Super 18 The Dakota Cub Super 18 is an American amateur-built aircraft, designed and produced by Dakota Cub of Sioux Falls, South Dakota. The aircraft is supplied as a kit for amateur construction.Vandermeullen, Richard: ''2012 Kit Aircraft Buyer's Gu ...

* Denney Kitfox * Foxcon Terrier 200 * Renegade Falcon LS *

Tecnam P92 The Tecnam P92 Echo and Tecnam P92 Eaglet are Italian high-winged, light aircraft, designed by Luigi Pascale and built by Tecnam of Naples. Design and development The P92 design dates to 1960, but versions comply with the Fédération Aéronau ...

* World Aircraft Spirit

Specifications (IO-233-LSA)

References

External links

Textron Lycoming
- Manufacturer's home page
Spec sheet showing images of IO-233
{{US military piston aeroengines 2000s aircraft piston engines Boxer engines IO-233