Lycoming Engines is a major American manufacturer of
aircraft engine
An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Aircraft using power components are referred to as powered flight. Most aircraft engines are either piston engines or gas turbin ...
s. With a factory in
Williamsport, Pennsylvania
Williamsport is a city in and the county seat of Lycoming County, Pennsylvania, United States. As of the 2020 census, it had a population of 27,754. It is the principal city of the Williamsport Metropolitan Statistical Area, which has a populati ...
, Lycoming produces a line of
horizontally opposed, air-cooled, four, six and eight-cylinder engines.
The company has built more than 325,000 piston aircraft engines and powers more than half the world's general aviation fleet, both rotary and
fixed wing.
["History: Decades of Pioneering Spirit"](_blank)
official website of Lycoming Engines, retrieved August 9, 2023
Lycoming has been a principal pioneer of turbine engines for medium and large helicopters, and has also produced engines for small jetliners and business jets.
[Angelucci, Enzo: ''Airplanes: From the Dawn of Flight to the Present Day,'' 1982 ed., Greenwich House / Arlington House, U.K.; retrieved August 8, 2023.][Young, Warren R., et.al.: ''The Helicopters,'' 1982, from the "Epic of Flight" series, Time-Life Books, Alexandria, Virginia, USA (cross-referenced with Angelucci's book)][Lambert, Mark, ed.: "Textron Lycoming" in "USA: Engines", ''Jane's All the World's Aircraft 1994–1995,'' 1994, pp. 756 et. seq., Jane's, Sentinel House, Surrey, UK/ Alexandria, Virginia, US; ]
Lycoming is an operating division of
Avco Corporation, itself a subsidiary of
Textron.
History
Sewing machines, bicycles and fashion

Lycoming dates its founding to 1845 by "
Madame Ellen Curtis Demorest".
However, the early history of the company (especially prior to 1860) is unclear;
biographer Ishbel Ross notes that the marriage of Ellen Louise Curtis to
William Jennings Demorest took place in 1858, somewhat later than the purported date of establishment of the company.
A few years later in
New York, between c. 1860 and 1887, the Demorests published fashion magazines and operated the Demorest Fashion and Sewing-Machine Company (sometimes known as the Demorest Manufacturing Company). They produced "Madame Demorest" and "Bartlett & Demorest" sewing machines and sold Ellen Demorest's innovative paper patterns for dressmaking.
During this period, Ellen Demorest patented several fashion accessories,
while her husband patented improvements to sewing machines
and an apparatus for the
vulcanization of rubber.
Around 1883, Gerrit S. Scofield & Frank M. Scofield (advertising agents from New York) bought the Demorest brand and the sewing machine business (the Demorests retained the magazine business), and constructed a factory in
Williamsport, Pennsylvania
Williamsport is a city in and the county seat of Lycoming County, Pennsylvania, United States. As of the 2020 census, it had a population of 27,754. It is the principal city of the Williamsport Metropolitan Statistical Area, which has a populati ...
(in
Lycoming County).
At the urging of the newly established Williamsport Board of Trade, citizens invested in the new manufacturing facility, which employed 250 people.
The factory produced 50 to 60 sewing machines per day.
With the development of the "New York Bicycle" in 1891 (designed by employee S. H. Ellis), the company diversified its product offerings.
Until the early 1900s, the factory produced
sewing machines,
bicycle
A bicycle, also called a pedal cycle, bike, push-bike or cycle, is a human-powered transport, human-powered or motorized bicycle, motor-assisted, bicycle pedal, pedal-driven, single-track vehicle, with two bicycle wheel, wheels attached to a ...
s,
typewriter
A typewriter is a Machine, mechanical or electromechanical machine for typing characters. Typically, a typewriter has an array of Button (control), keys, and each one causes a different single character to be produced on paper by striking an i ...
s, opera chairs and other products.
Engine manufacture
By 1907, the manufacture of sewing machines had become unprofitable for Demorest, and the company was sold and restructured as the Lycoming Foundry and Machine Company, shifting its focus toward
automobile
A car, or an automobile, is a motor vehicle with wheels. Most definitions of cars state that they run primarily on roads, Car seat, seat one to eight people, have four wheels, and mainly transport private transport#Personal transport, peopl ...
engine manufacture.
In 1910, the company supplied its first automobile engine to
Velie,
and during the early post-
World-War-I era, the company was a major supplier to Auburn (which produced the
Auburn,
Cord, and
Duesenberg lines).
By 1920, Lycoming was producing 60,000 engines a year, with a 2,000-strong workforce. To handle the capacity, a new foundry complex was built in
Williamsport that year.
Eventually Lycoming became Auburn's principal supplier, and in 1927
Errett Lobban Cord bought the company,
placing it under his Auburn Manufacturing umbrella group.
Among the engines Lycoming produced for Cord was an L-head
straight-eight engine of 298.5 cu. in. displacement that produced 125 horsepower. This was used in the Cord L-29. Lycoming also produced a double overhead cam straight 8 used in the legendary Duesenberg J series. This powerplant produced 265 horsepower, six times the power of a contemporary Model A Ford. A supercharged version, generating 325 horsepower, was installed in the Duesenberg SJ and SSJ models.
In 1929, Lycoming produced its first aviation engine, the nine-cylinder
R-680 radial.
This was a fairly successful design, and was used widely in light
aircraft
An aircraft ( aircraft) is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or the Lift (force), dynamic lift of an airfoil, or, i ...
, including Cord's
Travel Air.
In the 1930s, Lycoming made a number of attempts to develop successful high-power aircraft engines. The
O-1230 was Lycoming's attempt to produce an engine based on the
United States Army Air Corps
The United States Army Air Corps (USAAC) was the aerial warfare service component of the United States Army between 1926 and 1941. After World War I, as early aviation became an increasingly important part of modern warfare, a philosophical ri ...
hyper engine concept, and used a variety of features to produce nearly of
engine displacement
Engine displacement is the measure of the cylinder volume swept by all of the pistons of a piston engine, excluding the combustion chambers. It is commonly used as an expression of an engine's size, and by extension as an indicator of the ...
. However, by the O-1230's entry into service, it had been surpassed by other designs and the investment was not recouped.
Another attempt was made to rescue the design by stacking two O-1230s to make the
H engine
An H engine is a piston engine comprising two separate flat engine, flat engines (complete with separate crankshafts), most often geared to a common output shaft. The name "H engine" is due to the engine blocks resembling a letter "H" when viewe ...
H-2470 but the only design to use it, the
Vultee XP-54, never entered production. The
Curtiss XF14C was originally intended to be powered by the H-2470, but the engine's poor performance led to the adoption of an alternative radial engine on the prototype. (The XF14C did not enter production.)
Undeterred by the O-1230/H-2470's failure, Lycoming turned to an even larger design, the 36-cylinder
XR-7755, the largest aviation
piston engine
A reciprocating engine, more often known as a piston engine, is a heat engine that uses one or more Reciprocating motion, reciprocating pistons to convert high temperature and high pressure into a Circular motion, rotating motion. This article ...
ever built. This design also experienced problems, and was only ready for use at the very end of
World War II
World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...
, when the aviation world was turning to
turbojet
The turbojet is an airbreathing jet engine which is typically used in aircraft. It consists of a gas turbine with a propelling nozzle. The gas turbine has an air inlet which includes inlet guide vanes, a compressor, a combustion chamber, and ...
s and
turboprop
A turboprop is a Gas turbine, gas turbine engine that drives an aircraft Propeller (aeronautics), propeller.
A turboprop consists of an intake, reduction drive, reduction gearbox, gas compressor, compressor, combustor, turbine, and a propellin ...
engines to power future large aircraft.
There was apparently some interest in using it on the
Convair B-36 Peacemaker bomber
A bomber is a military combat aircraft that utilizes
air-to-ground weaponry to drop bombs, launch aerial torpedo, torpedoes, or deploy air-launched cruise missiles.
There are two major classifications of bomber: strategic and tactical. Strateg ...
, but the 28-cylinder
Pratt & Whitney R-4360 ''Wasp Major'' four-bank radial was used instead.
Through the 1920s and -30s, Lycoming had still been supplying automotive manufacturers with engines. However, these clients each slowly went out of business or switched to
Continental engines for their vehicles. By 1931, the company was supplying automotive engines to only three companies:
Auburn,
Cord and
Duesenburg, still all under the control of
Cord.
These companies closed their doors in 1937, after which Lycoming switched to exclusively designing and producing engines for aviation.
In the meantime, the Smith Engineering Corporation, an early manufacturer of controllable pitch propellers had been purchased by Cord and moved to Williamsport.
In 1939 Cord re-organized all of his aviation holdings into the AVCO group, at which point the engine manufacturing company became "AVCO Lycoming". It also leased the government-owned
Stratford Army Engine Plant in
Stratford, Connecticut, and produced
Wright radials under license. After the war, this plant was converted to produce the
T53 turboshaft
A turboshaft engine is a form of gas turbine that is optimized to produce shaft horsepower rather than jet thrust. In concept, turboshaft engines are very similar to turbojets, with additional turbine expansion to extract heat energy from the ex ...
engine, one of its more successful designs. From this point on the piston and
turbine
A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. The work produced can be used for generating electrical ...
engine lines remained separate, with the piston lines being built in the original Williamsport factories, and turbines in Stratford.
By 1961, Lycoming produced 600 to 700 engines per month.
Its most successful post-war products were a series of
air-cooled flat-4 and
flat-6 general aviation
General aviation (GA) is defined by the International Civil Aviation Organization (ICAO) as all civil aviation aircraft operations except for commercial air transport or aerial work, which is defined as specialized aviation services for other ...
engines. Most famous among these are the
O-320 and
O-360 four-cylinder engines, and the
O-540 six-cylinder engine.
["50 Amazing Aircraft Engines,"](_blank)
March 15, 2014, '' Flying,'' retrieved August 8, 2023[Wilson, Tom]
''2013 Engine Buyer’s Guide'': "Part 1: Traditional powerplants,"
February 14, 2013, ''Kitplanes,'' retrieved August 8, 2023 Many light aircraft are powered by versions of these engines, with power ratings in the range. Engines in this series also include the
O-235 four-,
O-580 six- and
O-720 eight-cylinder engines, and the advanced
turbocharged
In an internal combustion engine, a turbocharger (also known as a turbo or a turbosupercharger) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake air, forcing more air into the ...
and
fuel-injected TIGO-541 variant of the venerable (carbureted) O-540.
In the early 1980s, the general aviation market suddenly diminished and Lycoming's piston engine business was significantly impacted. Attempts were made to move some of the turbine production to Williamsport, but this led to a series of
quality control
Quality control (QC) is a process by which entities review the quality of all factors involved in production. ISO 9000 defines quality control as "a part of quality management focused on fulfilling quality requirements".
This approach plac ...
problems and eventually it was abandoned.
Another attempt to rescue Williamsport was made in introducing the "radical" ''SCORE'' engine, a
Wankel engine originally developed through a joint venture between
Curtiss-Wright
The Curtiss-Wright Corporation is an American manufacturer and services provider headquartered in Davidson, North Carolina, with factories and operations in and outside the United States. Created in 1929 from the consolidation (business), consoli ...
and
John Deere
Deere & Company, Trade name, doing business as John Deere (), is an American corporation that manufactures agricultural machinery, heavy equipment, forestry machinery, diesel engines, drivetrains (axles, Transmission (mechanical device), transmi ...
. Curtiss-Wright lost interest in the design just as it was maturing and sold its interests in the project to Deere, which brought in Lycoming to sell the developed engine into the aviation markets. It was guaranteed a startup run by
Cessna
Cessna () is an American brand of general aviation aircraft owned by Textron Aviation since 2014, headquartered in Wichita, Kansas. Originally, it was a brand of the Cessna Aircraft Company, an American general aviation aircraft manufactu ...
, also owned by Textron. Just as production was ready to start, Cessna announced it was halting its small-aircraft business for an indefinite period, and SCORE was cancelled. The remains of the Deere licenses were later purchased by Rotary Power International, which briefly produced a version.
Textron purchased the company in 1985.
In 1994, Textron sold the Lycoming Turbine Engine Division, located in
Stratford, Connecticut, to
AlliedSignal
AlliedSignal, Inc. was an American aerospace, automotive and engineering company, created through the 1985 merger of Allied Corp. and The Signal Companies. It purchased Honeywell for $14.8 billion in 1999, and adopted the Honeywell name and iden ...
, who merged it with the
Garrett Engine Division of AlliedSignal as part of AlliedSignal Aerospace, later becoming part of
Honeywell Aerospace
Honeywell Aerospace Technologies is a manufacturer of aircraft engines and avionics, as well as a producer of auxiliary power units (APUs) and other aviation products. Headquartered in Phoenix, Arizona, it is a division of the Honeywell Intern ...
in 1999.
[Leyes, p. 725] Textron retained piston engine production in Williamsport.
Lycomings continue to power new light aircraft by fellow Textron division,
Cessna Aircraft,
["Single-Engine Aircraft"](_blank)
on "Cessna" page, Cessna
Cessna () is an American brand of general aviation aircraft owned by Textron Aviation since 2014, headquartered in Wichita, Kansas. Originally, it was a brand of the Cessna Aircraft Company, an American general aviation aircraft manufactu ...
, retrieved June 29, 2023 and by
Piper,
["Models"](_blank)
Piper, retrieved June 29, 2023 Cirrus,
["Built for Flight Training,"](_blank)
Cirrus Aircraft, retrieved June 29, 2023 Diamond
Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of e ...
,
["Why Diamond"](_blank)
Diamond Aircraft, retrieved June 29, 2023 and others.
Lycomings remain the most popular line of engines for U.S. Experimental / Amateur-Built (E/A-B) aircraft, surpassing the 5 next-most-popular brands, combined.
[Wanttaja, Ron]
"Homebuilt Accidents: Passing the Engine Baton,"
December 19, 2022, ''Kitplanes,'' retrieved June 29, 2023
Products
The aircraft piston engine prefixes are:
* A—Aerobatic (dry sump)
* AE—Aerobatic (wet sump)
* E—Electronic
* G—Geared (reduction gear)
* H—Helicopter
* I—Fuel injected
* L—Left hand rotation crankshaft
* M—Designed for unmanned drone
* O—Opposed cylinders
* R—Radial cylinders
* S—Supercharged
* T—Turbocharged
* V—Vertical installation (usually for helicopters)
* X—
X-type engine
* Y—Experimental
Piston engines
Turbine engines
Lycoming was one of the principal pioneers of turbine engines --
turboshaft
A turboshaft engine is a form of gas turbine that is optimized to produce shaft horsepower rather than jet thrust. In concept, turboshaft engines are very similar to turbojets, with additional turbine expansion to extract heat energy from the ex ...
to be precise—for medium- and heavy-lift helicopters, some of which have found other applications as well. Its T53 hybrid
free turbine /
shaft turbine engine initially powered the
Bell UH-1 "Huey", and Lycoming's T55 is the main power for the twin-turbine, twin-rotor
Boeing CH-47 Chinook
The Boeing CH-47 Chinook is a tandem-rotor helicopter originally developed by American rotorcraft company Piasecki Helicopter, Vertol and now manufactured by Boeing Defense, Space & Security. The Chinook is a Military transport helicopter, heav ...
. Lycoming turbines have powered other helicopters, also.
[ John W. R. Taylor, ed.: "AVCO Lycoming" in "USA: Engines", ''Jane's All the World's Aircraft 1966-1967,'' 1967, pp.517 et. seq., Jane's, Bucks, England, U.K. / McGraw-Hill, New York, USA]
Variants and derivatives have powered various turboprop and turbofan aircraft, as well, including the
OV-1 Mohawk military aircraft,
BAe 146 jetliner,
Canadair Challenger business jet, and others.
See also
*
Continental Motors, Inc.
*
Rotax
*
Vericor Power Systems
References
Notes
Bibliography
*
*
External links
Official website
{{Textron
Textron
Aircraft engine manufacturers of the United States
Motor vehicle engine manufacturers
Williamsport, Pennsylvania
American companies established in 1845
Manufacturing companies established in 1845
1845 establishments in Pennsylvania
Manufacturing companies based in Pennsylvania
1985 mergers and acquisitions
Engine manufacturers of the United States
Turboshaft engine manufacturers