Aircraft diesel engine
Encyclopedia
The aircraft diesel engine or aero diesel has not been widely used as an aircraft engine
. Diesel engine
s were used in airships and were tried in aircraft in the late 1920s and 1930s, but never "caught on" in a major fashion. Its main advantage is its excellent specific fuel consumption and the somewhat higher density of its fuel, but these advantages have been outweighed by combination of its inherent disadvantages compared to gasoline-fueled or turboprop
engines, and the history of accidents.
The ever-rising cost of avgas
and doubts about its future availability have spurred a resurgence in aircraft diesel engine production in recent years.
air-cooled radial, and the Junkers Jumo 205
, which was moderately successful, but proved unsuitable for combat use in World War II
.
The first successful diesel engine developed specifically for aircraft was the Packard
radial
diesel of 1928-29, which was laid out in the familiar air-cooled radial format similar to Wright and Pratt & Whitney designs, and was contemporary with the Beardmore Tornado
used in the R101
airship
. The use of a diesel had been specified for its low fire risk fuel. The first successful flight of a diesel powered aircraft was made on September 18, 1928 in a Stinson model SM-IDX "Detroiter," registration number X7654 (presently owned by Greg Herrick, and based near Minneapolis, Minnesota).
Entering service in the early 1930s, the two-stroke Junkers Jumo 205
opposed-piston engine was much more widely used than previous aero diesels. It was moderately successful in its use in the Blohm & Voss Ha 139 and even more so in airship
use. In Britain Napier & Son
license-built the 205 as the Napier Culverin
, but it did not see production use in this form. A Daimler-Benz diesel engine
was also used in Zeppelin
s, including the ill-fated LZ 129 Hindenburg
. This engine proved unsuitable in military applications and subsequent German aircraft engine development concentrated on gasoline and jet engines.
The Soviet
World War II-era four-engine strategic
bomber
Petlyakov Pe-8
was built with Charomskiy ACh-30
diesel engines, but later in the production run diesels were replaced with radial
gasoline engines because of efficiency concerns. The Yermolaev Yer-2 long-range medium bomber was also built with Charomskiy diesel engines.
Other manufacturers also experimented with diesel engines in this period, such as the French Bloch
(later Dassault Aviation
), whose MB203 bomber prototype used Clerget
diesels of radial design. The Royal Aircraft Establishment
developed an experimental compression ignition (diesel) version of the Rolls-Royce Condor
in 1932, flying it in a Hawker Horsley
for test purposes.
of diesels, particularly compared to turboprop
engines, weighed against the diesel engine. With fuel available cheaply and most research interest in turboprops and jets for high-speed airliners, diesel-powered aircraft virtually disappeared. The near-death of the general aviation
market in the 1990s saw a massive decline in the development of any new aircraft engine types.
Napier & Son
in Britain had developed the Napier Culverin, a derivative of the Junkers Jumo 205
, before World War II, and took up aero diesel engines again in the 1950s. The British Air Ministry
supported the development of the 3000 hp Napier Nomad
, a combination of piston and turboprop engines, which was exceptionally efficient in terms of brake specific fuel consumption
, but judged too bulky and complex and canceled in 1955.
Certified diesel-powered light planes are currently available, and a number of companies are developing new engine and aircraft designs for the purpose. Many of these run on readily available jet fuel
(kerosene), or on conventional automotive diesel.
The zeppelin
s LZ 129 Hindenburg
and LZ 130 Graf Zeppelin II
were propelled by reversible diesel engines. The direction of operation was changed by shifting gears on the camshaft. From full power forward, the engines could be brought to a stop, changed over, and brought to full power in reverse in less than 60 seconds.
Nevil Shute Norway wrote that the demonstration flight of the airship R100
was changed from India to Canada, when she got petrol engines, because it was thought that a flight to the tropics with petrol on board would be too hazardous. It is curious after over twenty years to recall how afraid everyone was of petrol in those days (c. 1929), because since then aeroplanes with petrol engines have done innumerable hours of flying in the tropics, and they don’t burst into flames on every flight. I think the truth is that everyone was diesel-minded in those days; it seemed as if the diesel engine for aeroplanes was only just around the corner, with the promise of great fuel economy.
Hence, the ill-fated diesel-engined R101
— which crashed in 1930 — was to fly to India, though her diesel engines had petrol starter engines, and there had only been time to replace one with a diesel starter engine.
The R101 used the Beardmore Tornado
aero diesel engine, with two of the five engines reversible by an adjustment to the camshaft. This engine was developed from an engine used in railcar
s.
, located in the small town of Lichtenstein in the German state of Saxony
. They produce four-stroke, liquid-cooled, geared, turbo-diesel aircraft engines based on Mercedes automotive designs which will run on both diesel and jet aviation fuel (Jet A-1). Their first engine, a 1.7 litres (103.7 cu in), 135 hp four-cylinder (based on the 1.7 turbo diesel Mercedes A-class power unit), was first certified in 2002. It is certified for retrofitting to Cessna 172
s and Piper Cherokee
s which were originally equipped with the 160 hp Lycoming O-320
320 cubic inches (5.2 l) Avgas
engine. Although the weight of the 135 hp Thielert Centurion 1.7 at around 136 kilograms (299.8 lb) is similar to that of the 160 hp Lycoming O-320, its displacement is less than a third of that of the Lycoming. It however achieves maximum power at 2300 prop rpm (3900 crank rpm) as opposed to 2700 for the petrol Lycoming.
Thielert users included Austria
n aircraft firm Diamond Aircraft Industries
, which offered its single-engine Diamond DA40
-TDI Star with a Thielert Centurion 1.7' engine, and also the DA42 formerly known as Twin Star
with two. The twin-Thielert engined DA42 offered low fuel consumption with a high fuel efficiency of 15.1 l/h. Several hundred Thielert-powered airplanes are flying. There was also a certified a 4.0-litre, V8, 310 hp version available from 2005 although this engine has not been certified for installation in any airframes. Apex aircraft, formerly Robin, also offered an aircraft (Ecoflyer) with the Thielert engine.
In May 2008, Thielert went bankrupt. Although Bruno M. Kubler, Thielert's insolvency administrator, was able to announce in January 2009 that the company was "in the black and working to capacity," by then Cessna had dropped plans to install Thielert engines in some models, and Diamond Aircraft has now developed its own in-house diesel engine.
, located in Bourges
, 150 km south of Paris
have designed a four-stroke, air-cooled, turbo-diesel aircraft engine from the ground up, the SR305-230. SMA's engineering team came from Renault Sport (Formula 1). The 230 hp, 305 cubic inch (5.0 liter) jet fuel engine first obtained European certification in April 2001, followed by US FAA certification in July 2002. It is now certified as retrofit on several Cessna 182 models in Europe and the USA, and Maule is working toward certification of the M-9-230.
has been more limited, due to its lower fuel taxes. However, doubt about the future availability of avgas
has raised awareness of diesel alternatives. In March 2008 the Indus Aviation team led by Aldo Sibi (Director Of Production- Chief Mechanic – Head of Research and Development) prototyped the world's first diesel powered Light Sport Aircraft, N211GD. This airplane was built and flown in 30 days. This novel aircraft, although a prototype, sparked huge interest in alternative fuels in the industry. Mr. Sibi and his team also championed no less than 70 modifications and improvements. After the diesel project Mr. Sibi and his team took Indus to the next level developing the Primary Trainer. This was an attractive low cost trainer that competed very well with the high-end imports from overseas.
Diesel Air Limited, Wilksch and Zoche have all had considerable problems bringing their prototype designs into production, with delays running into several years. The Diesel Air Limited-powered airship is no longer registered by the Civil Aviation Authority in the UK.
Aircraft engine
An aircraft engine is the component of the propulsion system for an aircraft that generates mechanical power. Aircraft engines are almost always either lightweight piston engines or gas turbines...
. Diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
s were used in airships and were tried in aircraft in the late 1920s and 1930s, but never "caught on" in a major fashion. Its main advantage is its excellent specific fuel consumption and the somewhat higher density of its fuel, but these advantages have been outweighed by combination of its inherent disadvantages compared to gasoline-fueled or turboprop
Turboprop
A turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
engines, and the history of accidents.
The ever-rising cost of avgas
Avgas
Avgas is an aviation fuel used to power piston-engine aircraft. Avgas is distinguished from mogas , which is the everyday gasoline used in cars and some non-commercial light aircraft...
and doubts about its future availability have spurred a resurgence in aircraft diesel engine production in recent years.
Early diesel aircraft
A number of manufacturers built diesel aero engines in the 1920s and 30s; the best known were the PackardPackard
Packard was an American luxury-type automobile marque built by the Packard Motor Car Company of Detroit, Michigan, and later by the Studebaker-Packard Corporation of South Bend, Indiana...
air-cooled radial, and the Junkers Jumo 205
Junkers Jumo 205
The Junkers Jumo 205 aircraft engine was the most famous of a series of diesel engines that were the first, and for more than half a century, the only successful aircraft diesel engines. The Jumo 204 first entered service in 1932. Later engines in the series were styled Jumo 206, Jumo 207 and Jumo...
, which was moderately successful, but proved unsuitable for combat use in World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
The first successful diesel engine developed specifically for aircraft was the Packard
Packard
Packard was an American luxury-type automobile marque built by the Packard Motor Car Company of Detroit, Michigan, and later by the Studebaker-Packard Corporation of South Bend, Indiana...
radial
Radial engine
The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel...
diesel of 1928-29, which was laid out in the familiar air-cooled radial format similar to Wright and Pratt & Whitney designs, and was contemporary with the Beardmore Tornado
Beardmore Tornado
-Further reading:* Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9* Gunston, Bill. Development of Piston Aero Engines. Cambridge, England. Patrick Stephens Limited, 2006. ISBN 0-7509-4478-1* Lumsden, Alec. British Piston...
used in the R101
R101
R101 was one of a pair of British rigid airship completed in 1929 as part of a British government programme to develop civil airships capable of service on long-distance routes within the British Empire. It was designed and built by an Air Ministry-appointed team and was effectively in competition...
airship
Airship
An airship or dirigible is a type of aerostat or "lighter-than-air aircraft" that can be steered and propelled through the air using rudders and propellers or other thrust mechanisms...
. The use of a diesel had been specified for its low fire risk fuel. The first successful flight of a diesel powered aircraft was made on September 18, 1928 in a Stinson model SM-IDX "Detroiter," registration number X7654 (presently owned by Greg Herrick, and based near Minneapolis, Minnesota).
Entering service in the early 1930s, the two-stroke Junkers Jumo 205
Junkers Jumo 205
The Junkers Jumo 205 aircraft engine was the most famous of a series of diesel engines that were the first, and for more than half a century, the only successful aircraft diesel engines. The Jumo 204 first entered service in 1932. Later engines in the series were styled Jumo 206, Jumo 207 and Jumo...
opposed-piston engine was much more widely used than previous aero diesels. It was moderately successful in its use in the Blohm & Voss Ha 139 and even more so in airship
Airship
An airship or dirigible is a type of aerostat or "lighter-than-air aircraft" that can be steered and propelled through the air using rudders and propellers or other thrust mechanisms...
use. In Britain Napier & Son
Napier & Son
D. Napier & Son Limited was a British engine and pre-Great War automobile manufacturer and one of the most important aircraft engine manufacturers in the early to mid-20th century...
license-built the 205 as the Napier Culverin
Napier Culverin
-Bibliography:* Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.-External links:*...
, but it did not see production use in this form. A Daimler-Benz diesel engine
Daimler-Benz DB 602
|-See also:-Bibliography:* Gunston, Bill. World Encyclopaedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9* Neil Gregor Daimler-Benz in the Third Reich. Yale University Press, 1998-External links:...
was also used in Zeppelin
Zeppelin
A Zeppelin is a type of rigid airship pioneered by the German Count Ferdinand von Zeppelin in the early 20th century. It was based on designs he had outlined in 1874 and detailed in 1893. His plans were reviewed by committee in 1894 and patented in the United States on 14 March 1899...
s, including the ill-fated LZ 129 Hindenburg
LZ 129 Hindenburg
LZ 129 Hindenburg was a large German commercial passenger-carrying rigid airship, the lead ship of the Hindenburg class, the longest class of flying machine and the largest airship by envelope volume...
. This engine proved unsuitable in military applications and subsequent German aircraft engine development concentrated on gasoline and jet engines.
The Soviet
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
World War II-era four-engine strategic
Strategic bomber
A strategic bomber is a heavy bomber aircraft designed to drop large amounts of ordnance onto a distant target for the purposes of debilitating an enemy's capacity to wage war. Unlike tactical bombers, which are used in the battle zone to attack troops and military equipment, strategic bombers are...
bomber
Bomber
A bomber is a military aircraft designed to attack ground and sea targets, by dropping bombs on them, or – in recent years – by launching cruise missiles at them.-Classifications of bombers:...
Petlyakov Pe-8
Petlyakov Pe-8
The Petlyakov Pe-8 was a Soviet heavy bomber designed before World War II, and the only four-engine bomber the USSR built during the war. Produced in limited numbers, it was used to bomb Berlin in August 1941. It was also used for so-called "morale raids" designed to raise the spirit of the Soviet...
was built with Charomskiy ACh-30
Charomskiy ACh-30
-See also:-External links:*...
diesel engines, but later in the production run diesels were replaced with radial
Radial engine
The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel...
gasoline engines because of efficiency concerns. The Yermolaev Yer-2 long-range medium bomber was also built with Charomskiy diesel engines.
Other manufacturers also experimented with diesel engines in this period, such as the French Bloch
Société des Avions Marcel Bloch
The Société des Avions Marcel Bloch was a French aircraft manufacturer of military and civilian aircraft, that further changed its name in Dassault Aviation, after the end of World War II....
(later Dassault Aviation
Dassault Aviation
Dassault Aviation is a French aircraft manufacturer of military, regional and business jets, a subsidiary of Dassault Group.It was founded in 1930 by Marcel Bloch as Société des Avions Marcel Bloch or "MB". After World War II, Marcel Bloch changed his name to Marcel Dassault, and the name of the...
), whose MB203 bomber prototype used Clerget
Clerget
Clerget was the name given to a series of early rotary aircraft engine types of the World War I era that were designed by Pierre Clerget. Manufactured in both France by Clerget-Blin and Great Britain by Gwynne Limited, they were used on such aircraft as the Sopwith Camel and Vickers Gunbus.In the...
diesels of radial design. The Royal Aircraft Establishment
Royal Aircraft Establishment
The Royal Aircraft Establishment , was a British research establishment, known by several different names during its history, that eventually came under the aegis of the UK Ministry of Defence , before finally losing its identity in mergers with other institutions.The first site was at Farnborough...
developed an experimental compression ignition (diesel) version of the Rolls-Royce Condor
Rolls-Royce Condor
|-See also:-Bibliography:* Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.-External links:*...
in 1932, flying it in a Hawker Horsley
Hawker Horsley
|-See also:-Bibliography:* Jarrett, Philip. "By Day and By Night: Hawker Horsley part 1". Aeroplane Monthly, Volume 21 No 10, Issue 246, October 1993. pp. 32–40....
for test purposes.
Postwar development
Interest in diesel engines in the postwar period was sporadic. The lower power-to-weight ratioPower-to-weight ratio
Power-to-weight ratio is a calculation commonly applied to engines and mobile power sources to enable the comparison of one unit or design to another. Power-to-weight ratio is a measurement of actual performance of any engine or power sources...
of diesels, particularly compared to turboprop
Turboprop
A turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...
engines, weighed against the diesel engine. With fuel available cheaply and most research interest in turboprops and jets for high-speed airliners, diesel-powered aircraft virtually disappeared. The near-death of the general aviation
General aviation
General aviation is one of the two categories of civil aviation. It refers to all flights other than military and scheduled airline and regular cargo flights, both private and commercial. General aviation flights range from gliders and powered parachutes to large, non-scheduled cargo jet flights...
market in the 1990s saw a massive decline in the development of any new aircraft engine types.
Napier & Son
Napier & Son
D. Napier & Son Limited was a British engine and pre-Great War automobile manufacturer and one of the most important aircraft engine manufacturers in the early to mid-20th century...
in Britain had developed the Napier Culverin, a derivative of the Junkers Jumo 205
Junkers Jumo 205
The Junkers Jumo 205 aircraft engine was the most famous of a series of diesel engines that were the first, and for more than half a century, the only successful aircraft diesel engines. The Jumo 204 first entered service in 1932. Later engines in the series were styled Jumo 206, Jumo 207 and Jumo...
, before World War II, and took up aero diesel engines again in the 1950s. The British Air Ministry
Air Ministry
The Air Ministry was a department of the British Government with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964...
supported the development of the 3000 hp Napier Nomad
Napier Nomad
The Napier Nomad was a complex British compression-ignition aircraft engine designed and built by Napier & Son in 1949. Two versions were flight tested:...
, a combination of piston and turboprop engines, which was exceptionally efficient in terms of brake specific fuel consumption
Brake specific fuel consumption
Brake Specific Fuel Consumption is a measure of fuel efficiency within a shaft reciprocating engine.It is the rate of fuel consumption divided by the power produced. It may also be thought of as power-specific fuel consumption, for this reason...
, but judged too bulky and complex and canceled in 1955.
Modern developments
Several factors have emerged to change this equation. First, a number of new manufacturers of general aviation aircraft developing new designs have emerged. Second, in Europe in particular, avgas has become very expensive. Third, in several (particularly remote) locations, avgas is harder to obtain than diesel fuel. Finally, automotive diesel technologies have improved greatly in recent years, offering higher power-to-weight ratios more suitable for aircraft application.Certified diesel-powered light planes are currently available, and a number of companies are developing new engine and aircraft designs for the purpose. Many of these run on readily available jet fuel
Jet fuel
Jet fuel is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines. It is clear to straw-colored in appearance. The most commonly used fuels for commercial aviation are Jet A and Jet A-1 which are produced to a standardized international specification...
(kerosene), or on conventional automotive diesel.
Airships
Zeppelin
A Zeppelin is a type of rigid airship pioneered by the German Count Ferdinand von Zeppelin in the early 20th century. It was based on designs he had outlined in 1874 and detailed in 1893. His plans were reviewed by committee in 1894 and patented in the United States on 14 March 1899...
s LZ 129 Hindenburg
LZ 129 Hindenburg
LZ 129 Hindenburg was a large German commercial passenger-carrying rigid airship, the lead ship of the Hindenburg class, the longest class of flying machine and the largest airship by envelope volume...
and LZ 130 Graf Zeppelin II
LZ 130 Graf Zeppelin
The Graf Zeppelin II was the last of the great German rigid airships built by the Zeppelin Luftschiffbau during the period between the World Wars, the second and final ship of the Hindenburg class named in honor of Paul von Hindenburg...
were propelled by reversible diesel engines. The direction of operation was changed by shifting gears on the camshaft. From full power forward, the engines could be brought to a stop, changed over, and brought to full power in reverse in less than 60 seconds.
Nevil Shute Norway wrote that the demonstration flight of the airship R100
R100
HM Airship R100 was a privately designed and built rigid airship made as part of a two-ship competition to develop new techniques for a projected larger commercial airship for use on British empire routes...
was changed from India to Canada, when she got petrol engines, because it was thought that a flight to the tropics with petrol on board would be too hazardous. It is curious after over twenty years to recall how afraid everyone was of petrol in those days (c. 1929), because since then aeroplanes with petrol engines have done innumerable hours of flying in the tropics, and they don’t burst into flames on every flight. I think the truth is that everyone was diesel-minded in those days; it seemed as if the diesel engine for aeroplanes was only just around the corner, with the promise of great fuel economy.
Hence, the ill-fated diesel-engined R101
R101
R101 was one of a pair of British rigid airship completed in 1929 as part of a British government programme to develop civil airships capable of service on long-distance routes within the British Empire. It was designed and built by an Air Ministry-appointed team and was effectively in competition...
— which crashed in 1930 — was to fly to India, though her diesel engines had petrol starter engines, and there had only been time to replace one with a diesel starter engine.
The R101 used the Beardmore Tornado
Beardmore Tornado
-Further reading:* Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9* Gunston, Bill. Development of Piston Aero Engines. Cambridge, England. Patrick Stephens Limited, 2006. ISBN 0-7509-4478-1* Lumsden, Alec. British Piston...
aero diesel engine, with two of the five engines reversible by an adjustment to the camshaft. This engine was developed from an engine used in railcar
Railcar
A railcar, in British English and Australian English, is a self-propelled railway vehicle designed to transport passengers. The term "railcar" is usually used in reference to a train consisting of a single coach , with a driver's cab at one or both ends. Some railways, e.g., the Great Western...
s.
Germany
The first manufacturer to produce a certified design for the general aviation market was ThielertThielert
Thielert AG is a German financial holding company which has owned engine development and manufacturing companies. It is headquartered in Hamburg. Companies owned were Thielert Aircraft Engines GmbH with sites in Lichtenstein, Saxony and Altenburg, Thuringia and Superior Air Parts, Inc. in Dallas,...
, located in the small town of Lichtenstein in the German state of Saxony
Saxony
The Free State of Saxony is a landlocked state of Germany, contingent with Brandenburg, Saxony Anhalt, Thuringia, Bavaria, the Czech Republic and Poland. It is the tenth-largest German state in area, with of Germany's sixteen states....
. They produce four-stroke, liquid-cooled, geared, turbo-diesel aircraft engines based on Mercedes automotive designs which will run on both diesel and jet aviation fuel (Jet A-1). Their first engine, a 1.7 litres (103.7 cu in), 135 hp four-cylinder (based on the 1.7 turbo diesel Mercedes A-class power unit), was first certified in 2002. It is certified for retrofitting to Cessna 172
Cessna 172
The Cessna 172 Skyhawk is a four-seat, single-engine, high-wing fixed-wing aircraft. First flown in 1955 and still in production, more Cessna 172s have been built than any other aircraft.-Design and development:...
s and Piper Cherokee
Piper Cherokee
The Piper PA-28 Cherokee is a family of light aircraft designed for flight training, air taxi, and personal use. It is built by Piper Aircraft....
s which were originally equipped with the 160 hp Lycoming O-320
Lycoming O-320
The Lycoming O-320 is a large family of 92 different normally aspirated, air-cooled, four-cylinder, direct-drive engines commonly used on light aircraft such as the Cessna 172 and Piper Cherokee. Different variants are rated for 150 or 160 horsepower...
320 cubic inches (5.2 l) Avgas
Avgas
Avgas is an aviation fuel used to power piston-engine aircraft. Avgas is distinguished from mogas , which is the everyday gasoline used in cars and some non-commercial light aircraft...
engine. Although the weight of the 135 hp Thielert Centurion 1.7 at around 136 kilograms (299.8 lb) is similar to that of the 160 hp Lycoming O-320, its displacement is less than a third of that of the Lycoming. It however achieves maximum power at 2300 prop rpm (3900 crank rpm) as opposed to 2700 for the petrol Lycoming.
Thielert users included Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
n aircraft firm Diamond Aircraft Industries
Diamond Aircraft Industries
Diamond Aircraft Industries is an Austrian-based manufacturer of general aviation aircraft and motor gliders, which also has a large manufacturing facility in London, Ontario, Canada...
, which offered its single-engine Diamond DA40
Diamond DA40
The Diamond DA40 Diamond Star is an Austrian four-seat, single engine, light aircraft constructed from composite materials. Built in both Austria and Canada, it was developed as a four-seat version of the earlier DA20 by Diamond Aircraft Industries....
-TDI Star with a Thielert Centurion 1.7' engine, and also the DA42 formerly known as Twin Star
Diamond DA42
The Diamond DA42 Twin Star is a four seat, twin engine, propeller-driven airplane manufactured by Diamond Aircraft Industries. Its airframe is molded largely of composite materials.-Development:...
with two. The twin-Thielert engined DA42 offered low fuel consumption with a high fuel efficiency of 15.1 l/h. Several hundred Thielert-powered airplanes are flying. There was also a certified a 4.0-litre, V8, 310 hp version available from 2005 although this engine has not been certified for installation in any airframes. Apex aircraft, formerly Robin, also offered an aircraft (Ecoflyer) with the Thielert engine.
In May 2008, Thielert went bankrupt. Although Bruno M. Kubler, Thielert's insolvency administrator, was able to announce in January 2009 that the company was "in the black and working to capacity," by then Cessna had dropped plans to install Thielert engines in some models, and Diamond Aircraft has now developed its own in-house diesel engine.
France
SMA EnginesSMA Engines
SMA Engines is a French manufacturer of diesel engines for light aircraft. A subsidiary of Safran, SMA engine production is currently limited to one model, the SMA SR305-230, which has received a Supplemental Type Certificate for installation in the Cessna 182Q and R.-History:SMA was founded in...
, located in Bourges
Bourges
Bourges is a city in central France on the Yèvre river. It is the capital of the department of Cher and also was the capital of the former province of Berry.-History:...
, 150 km south of Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...
have designed a four-stroke, air-cooled, turbo-diesel aircraft engine from the ground up, the SR305-230. SMA's engineering team came from Renault Sport (Formula 1). The 230 hp, 305 cubic inch (5.0 liter) jet fuel engine first obtained European certification in April 2001, followed by US FAA certification in July 2002. It is now certified as retrofit on several Cessna 182 models in Europe and the USA, and Maule is working toward certification of the M-9-230.
United States
Interest in diesel aircraft in the United StatesUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
has been more limited, due to its lower fuel taxes. However, doubt about the future availability of avgas
Avgas
Avgas is an aviation fuel used to power piston-engine aircraft. Avgas is distinguished from mogas , which is the everyday gasoline used in cars and some non-commercial light aircraft...
has raised awareness of diesel alternatives. In March 2008 the Indus Aviation team led by Aldo Sibi (Director Of Production- Chief Mechanic – Head of Research and Development) prototyped the world's first diesel powered Light Sport Aircraft, N211GD. This airplane was built and flown in 30 days. This novel aircraft, although a prototype, sparked huge interest in alternative fuels in the industry. Mr. Sibi and his team also championed no less than 70 modifications and improvements. After the diesel project Mr. Sibi and his team took Indus to the next level developing the Primary Trainer. This was an attractive low cost trainer that competed very well with the high-end imports from overseas.
Experimental engine manufacturers
A number of other manufacturers are currently developing experimental diesel engines, many using aircraft-specific designs rather than adapted automotive engines. Many are using two-stroke designs, with some opposed-piston layouts directly inspired by the original Junkers design. Examples include:- Diesel Air Limited, a British company who are developing a 100 hp twin-cylinder (therefore four-piston), two-stroke opposed-piston engine inspired by the original Junkers design. Their engine has flown in test aircraft and airship installations. Unlike the Junkers, it is made for horizontal installation with a central output shaft for the geared cranks, the overall installed shape thereby approximately resembling a four-stroke flat-four engine.
- Powerplant Developments, a British company developing a 100 hp opposed-piston engine called the Gemini 100 that resembles the Diesel Air Limited engine and uses the Junkers twin-crank principle, again for horizontal installation with a central output shaft for the geared cranks. However, the Gemini 100 is a three-cylinder (therefore six-piston) engine. Like Diesel Air Limited, Powerplant Developments claim to be using WeslakeWeslakeWeslake Research and Development was founded by Harry Weslake, with premises in Rye, East Sussex, England. Weslake was a cylinder head specialist who had been instrumental in modifying the side valve standard engine used in the first SS sports car. He also worked on the larger SS engine: "The...
Air Services for production. They have recently announced that TecnamTecnamCostruzioni Aeronautiche Tecnam is an aeronautics manufacturer founded in 1948, based near Naples in Italy. The company has two primary activities: it makes aircraft parts for other manufacturers, and makes its own range of light aircraft.-History:...
will test a prototype with the Gemini engine. - Wilksch Airmotive, a British company who are developing/producing a 120 hp three-cylinder (WAM-120) two-stroke diesel and are working on a four-cylinder 160 hp design (WAM-160). In 2007 Wilksch claimed that they had completed multiple tests on the WAM-100 LSA in accordance with ASTM F 2538 - the WAM-100 LSA is a derated WAM-120. Wilksch originally showed a two-cylinder prototype alongside the three- and four-cylinder models. By mid-2009, approximately 40 WAM-120 units had been sold, with around half currently flying. The British owner of a RANS RV-9A fitted with a WAM-120 reports getting 125 knots (245 km/h) TASTrue airspeedTrue airspeed of an aircraft is the speed of the aircraft relative to the airmass in which it is flying. True airspeed is important information for accurate navigation of an aircraft.-Performance:...
at 6000 ft (1,828.8 m) on 15 litre/hr of jet A1 fuel. A Rutan LongEz canard-pusher (G-LEZE) has also flown with the WAM120 engine with test flights showing a TAS of 160 kn (313.6 km/h) at 11000 ft (3,352.8 m) and 22ltrs per hour. At economy cruise of 125 knots (245 km/h) at 2000 ft (609.6 m) the fuel consumption is 12 ltrs/hr giving a range of 1890 nautical miles (3,500.3 km); see http://www.longezediesel.com - Raptor Turbo Diesel LLC, an American company currently developing the Raptor 105 diesel engine. It is a four-stroke inline turbo charged engine. Known as Vulcan Aircraft Engines until September 2007.
- DeltaHawk Engines, an American company currently developing V-4, 160, 180 and 200 hp designs. Also using a two-stroke, ported design, they have also flown a prototype engine in a pusher configurationPusher configurationIn a craft with a pusher configuration the propeller are mounted behind their respective engine. According to Bill Gunston, a "pusher propeller" is one mounted behind engine so that drive shaft is in compression...
Velocity aircraft and are claiming delivery of non-certified engines since 2005 and hope to achieve certification early in 2011. DeltaHawk engines have a dry oil sump, so they can run in any orientation, upright, inverted or vertical shaft by changing the location of the oil scavenge port. They can also run counter-rotation for installation in twins. A watercooled DeltaHawk engine has been successfully fitted to a Rotorway helicopterHelicopterA helicopter is a type of rotorcraft in which lift and thrust are supplied by one or more engine-driven rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forwards, backwards, and laterally...
, weighing the same as an aircooled petrol engine of similar power and being capable of maintaining that power to 17,000 feet. - Eco-Motors, a company with sites in Germany and France, which developed an 100 hp aircraft engine based on a small turbocharged automotive diesel.
- GAP Diesel Engine, a NASANASAThe National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
development. - The Zoche outfit in Germany have produced a prototype range of three radialRadial engineThe radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel...
air-cooled two-stroke diesel aero-enginesAircraft engineAn aircraft engine is the component of the propulsion system for an aircraft that generates mechanical power. Aircraft engines are almost always either lightweight piston engines or gas turbines...
, comprising a V-twin, a single-row cross-4 and a double-row cross-8. A Zoche engine has run successfully in wind tunnelWind tunnelA wind tunnel is a research tool used in aerodynamic research to study the effects of air moving past solid objects.-Theory of operation:Wind tunnels were first proposed as a means of studying vehicles in free flight...
tests , but Zoche seem barely closer to production than they were a decade ago.
Diesel Air Limited, Wilksch and Zoche have all had considerable problems bringing their prototype designs into production, with delays running into several years. The Diesel Air Limited-powered airship is no longer registered by the Civil Aviation Authority in the UK.