View source for Gas-turbine engine

{{Short description|Type of internal and continuous combustion engine}}
{{Lead rewrite|date=October 2024}}
{{Use dmy dates|date=August 2019}}
[[File:Gas turbine applications (numbered).svg|thumb|upright=1.5|Examples of gas turbine configurations: (1) [[turbojet]], (2) [[turboprop]], (3) [[turboshaft]] (shown as electric generator), (4) high-bypass [[turbofan]], (5) low-bypass [[afterburning]] turbofan]]

A '''gas turbine engine''', or, informally, a '''gas turbine''', is a type of [[Internal combustion engine#Continuous combustion|continuous flow]] [[internal combustion engine]].<ref>{{cite book |title=A Dictionary of Aviation |first=David W. |last=Wragg |isbn=9780850451634 |edition=first |publisher=Osprey |year=1973 |page=141}}</ref> The main parts common to all gas turbine engines form the power-producing part (known as the gas generator or core) and are, in the direction of flow:
* a rotating [[gas compressor]]
* a [[combustor]]
* a compressor-driving [[turbine]].

Additional components have to be added to the gas generator to suit its application. Common to all is an air inlet but with different configurations to suit the requirements of marine use, land use or flight at speeds varying from stationary to supersonic. A propelling nozzle is added to produce thrust for flight. An extra turbine is added to drive a propeller ([[turboprop]]) or ducted fan ([[turbofan]]) to reduce fuel consumption (by increasing propulsive efficiency) at subsonic flight speeds. An extra turbine is also required to drive a helicopter rotor or land-vehicle transmission ([[turboshaft]]), marine propeller or electrical generator (power turbine). Greater [[thrust-to-weight ratio]] for flight is achieved with the addition of an [[afterburner]].

The basic operation of the gas turbine is a [[Brayton cycle]] with air as the [[working fluid]]: atmospheric air flows through the compressor that brings it to higher pressure; [[energy]] is then added by spraying fuel into the air and igniting it so that the combustion generates a high-temperature flow; this high-temperature pressurized gas enters a turbine, producing a shaft work output in the process, used to drive the compressor; the unused energy comes out in the exhaust gases that can be repurposed for external work, such as directly producing [[thrust]] in a [[turbojet engine]], or rotating a second, independent turbine (known as a ''power turbine'') that can be connected to a fan, propeller, or electrical generator. The purpose of the gas turbine determines the design so that the most desirable split of energy between the thrust and the shaft work is achieved. The fourth step of the Brayton cycle (cooling of the working fluid) is omitted, as gas turbines are [[Open system (systems theory)|open systems]] that do not reuse the same air.

Gas turbines are used to power among others [[aircraft]], [[train]]s, [[ship]]s, [[electric generator]]s, [[pump]]s, [[gas compressor]]s, and [[tank]]s.<ref>{{cite book |last1=Sonntag |first1=Richard E. |last2=Borgnakke |first2=Claus |title=Introduction to engineering thermodynamics |year=2006 |publisher=John Wiley |isbn=9780471737599 |edition= Second}}</ref>

{{TOC limit|3}}

==Timeline of development==
[[File:John Barber's gas turbine.jpg|thumb|upright=0.7|Sketch of John Barber's gas turbine, from his patent]]

*50: Earliest records of [[Hero of Alexandria|Hero's]] engine (''[[aeolipile]]''). It most likely served no practical purpose, and was rather more of a curiosity; nonetheless, it demonstrated an important principle of physics that all modern turbine engines rely on.<ref name=":SY1">{{Cite book| title= Gas Turbine Powerhouse|last=Eckardt |first=Dietrich |date=2014 |chapter =3.2 Early Attempts with the Gas Turbine Principle|publisher=Oldenbourg Verlag Munchen|language=en| isbn=9783486735710}}</ref>
*1000: The "Trotting Horse Lamp" ({{lang-zh|c=走马灯}}, ''zŏumădēng'') was used by the Chinese at lantern fairs as early as the [[Northern Song dynasty]]. When the lamp is lit, the heated airflow rises and drives an impeller with horse-riding figures attached on it, whose shadows are then projected onto the outer screen of the lantern.<ref>{{cite book |first1=B. |last1=Zhang |editor1-last=Lu |editor1-first=Yongxiang |title=A History of Chinese Science and Technology: Volume 3 |date=14 December 2014 |publisher=Springer Berlin Heidelberg |isbn=978-3662441626 |pages=308–310 |url=https://books.google.com/books?id=Js_lBAAAQBAJ&pg=PA310}}</ref>
*1500: The ''[[Smoke jack]]'' was drawn by [[Leonardo da Vinci]]: Hot air from a fire rises through a single-stage axial turbine rotor mounted in the exhaust duct of the fireplace and turns the roasting spit by gear-chain connection.
*1791: A patent was given to [[John Barber (engineer)|John Barber]], an Englishman, for the first true gas turbine. His invention had most of the elements present in the modern day gas turbines. The turbine was designed to power a [[horseless carriage]].<ref>{{cite web|url=http://web.mit.edu/aeroastro/labs/gtl/early_GT_history.html |title=Massachusetts Institute of Technology Gas Turbine Lab |publisher=Web.mit.edu |date=27 August 1939 |access-date=13 August 2012}}</ref><ref>UK patent no. 1833 – Obtaining and Applying Motive Power, & c. A Method of Rising Inflammable Air for the Purposes of Procuring Motion, and Facilitating Metallurgical Operations</ref>
*1894: Sir [[Charles Algernon Parsons|Charles Parsons]] patented the idea of propelling a ship with a [[steam turbine]], and built a demonstration vessel, the ''[[Turbinia]]'', easily the fastest vessel afloat at the time.
*1899: [[Charles Gordon Curtis]] patented the first gas turbine engine in the US.<ref>{{cite web|url=http://www.asme.org/Communities/History/Resources/Curtis_Charles_Gordon.cfm |title=History – Biographies, Landmarks, Patents |publisher=ASME |date=10 March 1905 |access-date=13 August 2012}}</ref>
*1900: [[Sanford Alexander Moss]] submitted a thesis on gas turbines. In 1903, Moss became an engineer for [[General Electric]]'s Steam Turbine Department in [[Lynn, Massachusetts]].<ref name="Leyes">Leyes, p.231-232.</ref> While there, he applied some of his concepts in the development of the [[turbocharger]].<ref name="Leyes"/>
*1903: A Norwegian, [[Ægidius Elling]], built the first gas turbine that was able to produce more power than needed to run its own components, which was considered an achievement in a time when knowledge about aerodynamics was limited. Using rotary compressors and turbines it produced {{cvt|11|hp|kW|order=flip|0}}.<ref name="ASMEAElling">Bakken, Lars E et al., p.83-88. "Centenary of the First Gas Turbine to Give Net Power Output: A Tribute to Ægidius Elling". ASME. 2004</ref>
*1904: A gas turbine engine designed by {{ill|Franz Stolze|de|Franz Stolze}}, based on his earlier 1873 patent application, is built and tested in Berlin.  The Stolze gas turbine was too inefficient to sustain its own operation.<ref name=":SY1"/>
*1906: The [[Armengaud-Lemale gas turbine]] tested in France.  This was a relatively large machine which included a 25-stage centrifugal compressor designed by [[Auguste Rateau]] and built by the [[Brown Boveri Company]]. The gas turbine could sustain its own air compression but was too inefficient to produce useful work.<ref name=":SY1"/>
*1910: The first operational [[Holzwarth gas turbine]] (pulse combustion) achieves an output of {{cvt|150|kW|hp|round=5}}. Planned output of the machine was {{cvt|1,000|hp|kW|round=50|order=flip}} and its efficiency is below that of contemporary reciprocating engines.<ref>{{Cite book |last=Eckardt |first=Dietrich |title=Jet Web |date=2022 |publisher=Springer |isbn=9783658385309 |pages=27}}</ref>
*1920s The practical theory of gas flow through passages was developed into the more formal (and applicable to turbines) theory of gas flow past airfoils by [[Alan Arnold Griffith|A. A. Griffith]] resulting in the publishing in 1926 of ''An Aerodynamic Theory of Turbine Design''. Working testbed designs of axial turbines suitable for driving a propeller were [[Turbojet development at the RAE|developed by the Royal Aeronautical Establishment]].<ref name=":SY2">{{cite journal |last1=Armstrong |first1=F.W |date=2020 |title=Farnborough and the Beginnings of Gas Turbine Propulsion |url=https://www.aerosociety.com/media/13850/paper-2020-02-armstrong-gas-turbines.pdf|journal=Journal of Aeronautical History|publisher=Royal Aeronautical Society}}</ref>
*1930: Having found no interest from the RAF for his idea, [[Frank Whittle]] patented<ref>{{cite web|url=http://www.frankwhittle.co.uk/content.php?act=viewDoc&docId=4&docFatherId=1&level=sub|title=Welcome to the Frank Whittle Website|website=www.frankwhittle.co.uk|access-date=22 October 2016|archive-url=https://web.archive.org/web/20120213182253/http://www.frankwhittle.co.uk/content.php?act=viewDoc&docId=4&docFatherId=1&level=sub|archive-date=13 February 2012|url-status=dead}}</ref> the design for a centrifugal gas turbine for [[jet propulsion]]. The first successful test run of his engine occurred in England in April 1937.<ref>{{cite book |title=The CRC Handbook of Mechanical Engineering |edition= Second |editor-first=Frank |editor-last=Kreith |isbn=978-0-8493-9418-8 |page= 222 |year=1998 |publisher=CRC Press |location=US}}</ref>
*1932: The [[Brown Boveri Company]] of Switzerland starts selling [[axial compressor]] and turbine turbosets as part of the turbocharged steam generating [[Velox boiler]]. Following the gas turbine principle, the steam [[evaporation]] tubes are arranged within the gas turbine combustion chamber; the first Velox plant is erected at a French [[Steel mill]] in [[Mondeville, Calvados]].<ref>{{cite web |url=http://www.ruhr-uni-bochum.de/fem/pdf/in-touch-magazin2005.pdf |title=University of Bochum "In Touch Magazine 2005", p. 5 |access-date=13 August 2012 |archive-url=https://web.archive.org/web/20120313093034/http://www.ruhr-uni-bochum.de/fem/pdf/in-touch-magazin2005.pdf |archive-date=13 March 2012 |url-status=dead }}</ref>
*1936: The first constant flow industrial gas turbine is commissioned by the Brown Boveri Company and goes into service at [[Sunoco|Sun Oil]]'s [[Marcus Hook, Pennsylvania|Marcus Hook]] refinery in [[Pennsylvania]], US.<ref name=":SY4">{{Cite book| title=Introduction to Gas Turbine Theory|last1=Brun|first1=Klaus|last2=Kurz|first2= Rainer|date=2019|publisher=Solar Turbines Incorporated|pages=15|edition= 4|language=en|isbn=978-0-578-48386-3}}</ref> 
*1937: Working proof-of-concept prototype turbojet engine runs in UK (Frank Whittle's) and Germany ([[Hans von Ohain]]'s [[Heinkel HeS 1]]). [[Henry Tizard]] secures UK government funding for further development of ''Power Jets'' engine.<ref name="JETbook">John Golley. 1996. "Jet: Frank Whittle and the invention of the jet engine". {{ISBN|978-1-907472-00-8}}</ref>
*1939: The First 4 MW utility power generation gas turbine is built by the Brown Boveri Company for an [[Neuchâtel gas turbine|emergency power station in Neuchâtel, Switzerland]].<ref>Eckardt, D. and Rufli, P. "Advanced Gas Turbine Technology – ABB/ BBC Historical Firsts", ASME J. Eng. Gas Turb. Power, 2002, p. 124, 542–549</ref> The turbojet powered [[Heinkel He 178]], the world's first jet aircraft, makes its first flight.
*1940: [[Jendrassik Cs-1]], a [[turboprop]] engine, made its first bench run. The Cs-1 was designed by Hungarian engineer [[György Jendrassik]], and was intended to power a Hungarian twin-engine heavy fighter, the RMI-1. Work on the Cs-1 stopped in 1941 without the type having powered any aircraft.<ref>{{Cite book |last=Eckardt |first=Dietrich |title=Jet Web |date=2022 |publisher=Springer |isbn=978-3-658-38531-6 |location=Wiesbaden, Germany |pages=399 |chapter=Early Turbojet Developments in the USA and Other Countries}}</ref> 
*1944: The [[Junkers Jumo 004]] engine enters full production, powering the first German military jets such as the [[Messerschmitt Me 262]]. This marks the beginning of the reign of gas turbines in the sky.
*1946: [[National Gas Turbine Establishment]] formed from Power Jets and the RAE turbine division to bring together Whittle and [[Hayne Constant]]'s work.<ref>{{Cite book|url=https://books.google.com/books?id=BWopDQAAQBAJ&q=%3A+national+gas+turbine+establishment+whittle+and+hayne+constant&pg=PA181|title=Making Jet Engines in World War II: Britain, Germany, and the United States|last=Giffard|first=Hermione|date=2016-10-10|publisher=University of Chicago Press|isbn=978-0-226-38859-5|language=en}}</ref> In [[Beznau Nuclear Power Plant|Beznau]], Switzerland the first commercial reheated/recuperated unit generating 27 MW was commissioned.<ref>Eckardt, D. "Gas Turbine Powerhouse". 2014. {{ISBN|978-3-11-035962-6}}</ref>
*1947: A [[Metropolitan-Vickers|Metropolitan Vickers]] G1 (Gatric) becomes the first marine gas turbine when it completes sea trials on the [[Motor gunboat|Royal Navy's M.G.B 2009 vessel]]. The Gatric was an aeroderivative gas turbine based on the [[Metropolitan-Vickers F.2|Metropolitan Vickers F2]] jet engine.<ref>{{cite news|title=Post War Advances in Propulsion| url=https://login.thetimes.com/?gotoUrl=https%3A%2F%2Fwww.thetimes.com%2Farchive%2Farticle%2F1953-06-15%2F20%2F2.html | work=[[The Times]]| page=20| date=15 June 1953|access-date=8 Jan 2021}}</ref><ref>{{Cite report|title=The Marine Gas Turbine-The UK Provides a Case Study in Technological Development|last=Nunn|first=Robert H|date=25 February 1977|publisher=US Office of Naval Research|pages=5|url=https://apps.dtic.mil/dtic/tr/fulltext/u2/a037686.pdf|archive-url=https://web.archive.org/web/20210419065804/https://apps.dtic.mil/dtic/tr/fulltext/u2/a037686.pdf|url-status=live|archive-date=19 April 2021}}</ref> 
*1995: [[Siemens]] becomes the first manufacturer of large electricity producing gas turbines to incorporate [[single crystal]] [[turbine blade]] technology into their production models, allowing higher operating temperatures and greater efficiency.<ref>{{cite web |url=https://www.americanscientist.org/article/each-blade-a-single-crystal |title=Each Blade a Single Crystal |work=American Scientist |first=Lee S. |last=Langston |access-date=2019-01-25|date=6 February 2017 }}</ref>
*2011: [[Mitsubishi Heavy Industries]] tests the first >60% efficiency [[combined cycle]] gas turbine (the M501J) at its Takasago, Hyōgo, works.<ref>{{cite web |url=https://www.mhi-global.com/company/technology/review/pdf/e491/e491018.pdf |title=Test Results of the World's First 1,600C J-series Gas Turbine |first=Satoshi |last=Hada |access-date=15 October 2015 |display-authors=etal |archive-date=16 October 2015 |archive-url=https://web.archive.org/web/20151016100414/https://www.mhi-global.com/company/technology/review/pdf/e491/e491018.pdf |url-status=dead }}</ref><ref>{{cite web |url=http://www.cospp.com/articles/print/volume-11/issue-3/features/gas-turbines-breaking.html |title=Gas Turbines breaking the 60% efficiency barrier |website=Cogeneration & On-Site Power Production |date=5 January 2010 |url-status=dead |archive-url=https://web.archive.org/web/20130930233542/http://www.cospp.com/articles/print/volume-11/issue-3/features/gas-turbines-breaking.html |archive-date=2013-09-30}}</ref>

==Theory of operation==
[[File:Brayton cycle.svg|thumb|The [[Brayton cycle]] ]]

In an ideal gas turbine, gases undergo four [[thermodynamics|thermodynamic]] processes: an [[isentropic]] compression, an [[isobaric process|isobaric]] (constant pressure) combustion, an isentropic expansion and isobaric heat rejection. Together, these make up the [[Brayton cycle]], also known as the [[Brayton cycle|"constant pressure cycle"]].<ref name=":0" /> It is distinguished from the [[Otto cycle]], in that all the processes (compression, ignition combustion, exhaust), occur at the same time, continuously.<ref name=":0" />

In a real gas turbine, mechanical energy is changed irreversibly (due to internal friction and turbulence) into pressure and thermal energy when the gas is compressed (in either a centrifugal or axial [[Gas compressor|compressor]]). Heat is added in the [[combustor|combustion chamber]] and the [[specific volume]] of the gas increases, accompanied by a slight loss in pressure. During expansion through the stator and rotor passages in the turbine, irreversible energy transformation once again occurs. Fresh air is taken in, in place of the heat rejection.

Air is taken in by a compressor, called a [[gas generator]], with either an [[axial compressor|axial]] or [[centrifugal compressor|centrifugal]] design, or a combination of the two.<ref name=":0" /> This air is then ducted into the [[combustor]] section which can be of a [[Annular combustor|annular]], [[Can combustor|can]], or [[can-annular]] design.<ref name=":0" /> In the combustor section, roughly 70% of the air from the compressor is ducted around the combustor itself for cooling purposes.<ref name=":0" /> The remaining roughly 30% the air is mixed with fuel and ignited by the already burning [[air-fuel mixture]], which then expands producing power across the [[turbine]].<ref name=":0" /> This expansion of the mixture then leaves the combustor section and has its velocity increased across the [[turbine]] section to strike the turbine blades, spinning the disc they are attached to, thus creating useful power. Of the power produced, 60-70% is solely used to power the gas generator.<ref name=":0" /> The remaining power is used to power what the engine is being used for, typically an aviation application, being thrust in a [[turbojet]], driving the fan of a [[turbofan]], rotor or accessory of a [[turboshaft]], and gear reduction and propeller of a [[turboprop]].<ref name=":1" /><ref name=":0" />

If the engine has a power turbine added to drive an industrial generator or a helicopter rotor, the exit pressure will be as close to the entry pressure as possible with only enough energy left to overcome the pressure losses in the exhaust ducting and expel the exhaust. For a [[turboprop]] engine there will be a particular balance between propeller power and jet thrust which gives the most economical operation. In a [[turbojet engine]] only enough pressure and energy is extracted from the flow to drive the compressor and other components. The remaining high-pressure gases are accelerated through a nozzle to provide a jet to propel an aircraft.

The smaller the engine, the higher the rotation rate of the shaft must be to attain the required blade tip speed. Blade-tip speed determines the maximum pressure ratios that can be obtained by the turbine and the compressor. This, in turn, limits the maximum power and efficiency that can be obtained by the engine. In order for tip speed to remain constant, if the diameter of a rotor is reduced by half, the [[rotational speed]] must double. For example, large jet engines operate around 10,000–25,000 rpm, while micro turbines spin as fast as 500,000&nbsp;rpm.<ref>{{cite conference |url=http://www.isma-isaac.be/publications/PMA_MOD_publications/ISMA2006/181-198.pdf |title=Rotordynamic behaviour of a micro-turbine rotor on air bearings: modelling techniques and experimental verification, p. 182 |first1=T. |last1=Waumans |first2=P. |last2=Vleugels |first3=J. |last3=Peirs |first4=F. |last4=Al-Bender |first5=D. |last5=Reynaerts |publisher=International Conference on Noise and Vibration Engineering |conference=ISMA |year=2006 |access-date=7 January 2013 |archive-url=https://web.archive.org/web/20130225144713/http://www.isma-isaac.be/publications/PMA_MOD_publications/ISMA2006/181-198.pdf |archive-date=2013-02-25 |url-status=dead}}</ref>

Mechanically, gas turbines ''can'' be considerably less complex than [[Reciprocating engine]]s. Simple turbines might have one main moving part, the compressor/shaft/turbine rotor assembly, with other moving parts in the fuel system. This, in turn, can translate into price. For instance, costing {{currency|10,000|RM}} for materials, the Jumo 004 proved cheaper than the [[Junkers Jumo 213|Junkers 213]] piston engine, which was {{currency|35,000|RM}},<ref>Christopher, John. ''The Race for Hitler's X-Planes'' (The Mill, Gloucestershire: History Press, 2013), p.74.</ref> and needed only 375 hours of lower-skill labor to complete (including manufacture, assembly, and shipping), compared to 1,400 for the [[BMW 801]].<ref>Christopher, p.75.</ref> <!--Christopher isn't clear if this only applied to the 004s, so confirmation is wanted here....-->This, however, also translated into poor efficiency and reliability. More advanced gas turbines (such as those found in modern [[turbofan|jet engines]] or combined cycle power plants) may have 2 or 3 shafts (spools), hundreds of compressor and turbine blades, movable stator blades, and extensive external tubing for fuel, oil and air systems; they use temperature resistant alloys, and are made with tight specifications requiring precision manufacture. All this often makes the construction of a simple gas turbine more complicated than a piston engine.

Moreover, to reach optimum performance in modern gas turbine power plants the gas needs to be prepared to exact fuel specifications. Fuel gas conditioning systems treat the natural gas to reach the exact fuel specification prior to entering the turbine in terms of pressure, temperature, gas composition, and the related [[Wobbe index]].

The primary advantage of a gas turbine engine is its power to weight ratio.{{citation needed|date=January 2019}} 
Since significant useful work can be generated by a relatively lightweight engine, gas turbines are perfectly suited for aircraft propulsion.

[[Thrust bearing]]s and [[journal bearings]] are a critical part of a design. They are [[Fluid bearing|hydrodynamic oil bearings]] or oil-cooled [[rolling-element bearing]]s. [[Foil bearing]]s are used in some small machines such as micro turbines<ref>{{cite journal |url=http://www.uwm.edu.pl/wnt/technicalsc/tech_12/B19.pdf |title=Development of the foil bearing technology |first1=Krzysztof|last1=Nalepa | first2=Paweł|last2=Pietkiewicz |first3=Grzegorz|last3=Żywica |s2cid-access=free |via=Uniwersytet Warmińsko-Mazurski w Olsztynie | journal=Technical Sciences|volume=12|pages=229–240|s2cid= 44838086|doi=10.2478/v10022-009-0019-2 |date=November 2009 |doi-broken-date= 12 July 2025|access-date=2022-03-01}}</ref> and also have strong potential for use in small gas turbines/[[auxiliary power unit]]s<ref>{{cite conference |last=Agrawal |first=Giri L. |title=Foil Air/Gas Bearing Technology – An Overview |conference=ASME 1997 International Gas Turbine and Aeroengine Congress and Exhibition |pages=V001T04A006 |date=2 June 1997 |doi=10.1115/97-GT-347 |url= http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2088143 |access-date=23 July 2018|isbn=978-0-7918-7868-2 |url-access=subscription }}</ref>

===Creep===
A major challenge facing turbine design, especially [[turbine blades]], is reducing the [[creep (deformation)|creep]] that is induced by the high temperatures and stresses that are experienced during operation. Higher operating temperatures are continuously sought in order to increase efficiency, but come at the cost of higher creep rates. Several methods have therefore been employed in an attempt to achieve optimal performance while limiting creep, with the most successful ones being high performance coatings and single crystal [[superalloy]]s.<ref>{{cite conference |first1=Brian |last1=Hazel |first2=Joe |last2=Rigney |first3=Mark |last3=Gorman |first4=Brett |last4=Boutwell |first5=Ram |last5=Darolia |title=Superalloys 2008 (Eleventh International Symposium) |chapter=Development of Improved Bond Coat for Enhanced Turbine Durability |doi=10.7449/2008/Superalloys_2008_753_760 |conference =Superalloys |publisher=The Minerals, Metals & Materials Society |location=US |year=2008|pages=753–760 |isbn=978-0-87339-728-5 |doi-access=free }}</ref> These technologies work by limiting deformation that occurs by mechanisms that can be broadly classified as dislocation glide, dislocation climb and diffusional flow.

Protective coatings provide [[thermal insulation]] of the blade and offer [[oxidation]] and [[corrosion]] resistance. Thermal barrier coatings (TBCs) are often stabilized [[zirconium dioxide]]-based ceramics and oxidation/corrosion resistant coatings (bond coats) typically consist of [[aluminide]]s or MCrAlY (where M is typically Fe and/or Cr) alloys. Using TBCs limits the temperature exposure of the superalloy substrate, thereby decreasing the diffusivity of the active species (typically vacancies) within the alloy and reducing dislocation and vacancy creep. It has been found that a coating of 1–200 μm can decrease blade temperatures by up to {{convert|200|C}}.<ref>{{Cite web|url=https://www.phase-trans.msm.cam.ac.uk/2003/Superalloys/coatings/index.html|title=Coatings for Turbine Blades|website=www.phase-trans.msm.cam.ac.uk}}</ref> 
Bond coats are directly applied onto the surface of the substrate using pack carburization and serve the dual purpose of providing improved adherence for the TBC and oxidation resistance for the substrate. The Al from the bond coats forms Al<sub>2</sub>O<sub>3</sub> on the TBC-bond coat interface which provides the oxidation resistance, but also results in the formation of an undesirable interdiffusion (ID) zone between itself and the substrate.<ref>A. W. James et al. "Gas turbines: operating conditions, components and material requirements"</ref> The oxidation resistance outweighs the drawbacks associated with the ID zone as it increases the lifetime of the blade and limits the efficiency losses caused by a buildup on the outside of the blades.<ref>Tamarin, Y. Protective Coatings for Turbine Blades. 2002. ASM International. pp 3–5</ref>

Nickel-based superalloys boast improved strength and creep resistance due to their composition and resultant [[microstructure]]. The gamma (γ) FCC nickel is alloyed with aluminum and titanium in order to precipitate a uniform dispersion of the coherent {{chem2|Ni3(Al,Ti)}} gamma-prime (γ') phases. The finely dispersed γ' precipitates impede dislocation motion and introduce a threshold stress, increasing the stress required for the onset of creep. Furthermore, γ' is an ordered L1<sub>2</sub> phase that makes it harder for dislocations to shear past it.<ref>A. Nowotnik "Nickel-Based Superalloys"</ref> Further [[Refractory]] elements such as [[rhenium]] and [[ruthenium]] can be added in solid solution to improve creep strength. The addition of these elements reduces the diffusion of the gamma prime phase, thus preserving the [[Fatigue (material)|fatigue]] resistance, strength, and creep resistance.<ref>Latief, F. H.; Kakehi, K. (2013) "Effects of Re content and crystallographic orientation on creep behavior of aluminized Ni-based single crystal superalloys". Materials & Design 49 : 485–492</ref> The development of single crystal superalloys has led to significant improvements in creep resistance as well. Due to the lack of grain boundaries, single crystals eliminate [[Coble creep]] and consequently deform by fewer modes – decreasing the creep rate.<ref>Caron P., Khan T. "Evolution of Ni-based superalloys for single crystal gas turbine blade applications"</ref> Although single crystals have lower creep at high temperatures, they have significantly lower yield stresses at room temperature where strength is determined by the Hall-Petch relationship. Care needs to be taken in order to optimize the design parameters to limit high temperature creep while not decreasing low temperature yield strength.

==Types==
[[File:Jet engine types.png|thumb|Jet engine types]]

===Jet engines===
[[File:J85 ge 17a turbojet engine.jpg|thumb|Typical axial-flow gas turbine turbojet, the [[General Electric J85|J85]], sectioned for display. Flow is left to right, multistage compressor on left, combustion chambers center, two-stage turbine on right.]]
{{Main|Jet engine}}

Airbreathing jet engines are gas turbines optimized to produce thrust from the exhaust gases, or from [[ducted fan]]s connected to the gas turbines.<ref>{{cite tech report |url=https://pure.manchester.ac.uk/ws/files/83828293/Modelling_of_a_Turbojet_Gas_Turbine_Engine.pdf |title=Modelling of a turbojet gas turbine engine |last1=Klein |first1=D. |last2=Abeykoon |first2=C. |publisher=University of Manchester |year=2015}}</ref><ref name="Dk">{{cite journal|last=Dick |first=Erik |title=Thrust Gas Turbines |journal=Fundamentals of Turbomachines |volume=109 |year=2015}}</ref> Jet engines that produce thrust from the direct impulse of exhaust gases are often called [[turbojet]]s. While still in service with many militaries and civilian operators, turbojets have mostly been phased out in favor of the [[turbofan]] engine due to the turbojet's low fuel efficiency, and high noise.<ref name=":0">{{Cite book |url=https://www.faa.gov/sites/faa.gov/files/regulations_policies/handbooks_manuals/aviation/FAA-H-8083-32-AMT-Powerplant-Vol-1.pdf |title=8083 Aviation Maintenance Technician Handbook–Powerplant Volume 1 |publisher=Federal Aviation Administration |year=2018 |isbn=978-0983865810 |location=USA}}</ref> Those that generate thrust with the addition of a ducted fan are called [[turbofan]]s or (rarely) fan-jets. These engines produce nearly 80% of their thrust by the ducted fan, which can be seen from the front of the engine. They come in two types, [[low-bypass turbofan]] and [[high bypass]], the difference being the amount of air moved by the fan, called "bypass air". These engines offer the benefit of more thrust without extra fuel consumption.<ref name=":0" /><ref name=":1">{{Cite book |title=A&P Powerplant Textbook |publisher=Jeppeson |year=2011 |isbn=978-0884873389 |edition=3rd}}</ref>

Gas turbines are also used in many [[liquid-fuel rocket]]s, where gas turbines are used to power a [[turbopump]] to permit the use of lightweight, low-pressure tanks, reducing the empty weight of the rocket.

===Turboprop engines===
{{Main|Turboprop}}

A turboprop engine is a turbine engine that drives an aircraft propeller using a reduction gear to translate high turbine section operating speed (often in the 10s of thousands) into low thousands necessary for efficient propeller operation. The benefit of using the turboprop engine is to take advantage of the turbine engines high [[power-to-weight ratio]] to drive a propeller, thus allowing a more powerful, but also smaller engine to be used.<ref name=":1" /> Turboprop engines are used on a wide range of [[business aircraft]] such as the [[Pilatus PC-12]], [[commuter aircraft]] such as the [[Beechcraft 1900]], and small cargo aircraft such as the [[Cessna 208 Caravan]] or [[De Havilland Canada Dash 8]], and large aircraft (typically military) such as the [[Airbus A400M]] transport, [[Lockheed AC-130]] and the 60-year-old [[Tupolev Tu-95]] strategic bomber. While military turboprop engines can vary, in the civilian market there are two primary engines to be found: the [[Pratt & Whitney Canada PT6]], a [[free-turbine turboshaft]] engine, and the [[Honeywell TPE331]], a [[fixed turbine]] engine (formerly designated as the [[Garrett AiResearch]] 331).

===Aeroderivative gas turbines===
[[File:General Electric LM6000.jpg|thumb|An LM6000 in an electrical [[power plant]] application]]

Aeroderivative gas turbines are generally based on existing aircraft gas turbine engines and are smaller and lighter than industrial gas turbines.<ref name="Robb">{{cite web|url=https://www.turbomachinerymag.com/aeroderivative-gas-turbines/|title=Aeroderivative gas turbines|last=Robb|first=Drew|date=December 1, 2017|work=Turbomachinery International Magazine|access-date=26 June 2020}}</ref>

Aeroderivatives are used in electrical power generation due to their ability to be shut down and handle load changes more quickly than industrial machines.<ref>{{cite conference |first=R. P. |last=Smith |title= Power generation using high efficiency aeroderivative gas turbines |conference= International Conference on Opportunities and Advances in International Electric Power Generation (Conf. Publ. No. 419) |location= Durham, UK |year= 1996 |pages= 104–110 |doi= 10.1049/cp:19960128 |url= https://ieeexplore.ieee.org/document/643453 |url-access= subscription}}</ref> They are also used in the marine industry to reduce weight. Common types include the [[General Electric LM2500]], [[General Electric LM6000]], and aeroderivative versions of the [[Pratt & Whitney PW4000]], [[Pratt & Whitney FT4]] and [[Rolls-Royce RB211]].<ref name="Robb"/>

===Amateur gas turbines===
Increasing numbers of gas turbines are being used or even constructed by amateurs.

In its most straightforward form, these are commercial turbines acquired through military surplus or scrapyard sales, then operated for display as part of the hobby of engine collecting.<ref name="latexiron" >{{cite web|url= http://www.vb.n00bunlimited.net/vBTube.php?do=view&vidid=5iQRdBE3IS0 |archive-url= https://archive.today/20130413204957/http://www.vb.n00bunlimited.net/vBTube.php?do=view&vidid=5iQRdBE3IS0 |url-status= dead |archive-date= 13 April 2013 |title=Vulcan APU startup |format=video}}</ref><ref name="Internal Fire, Proteus">{{cite web|title=Bristol Siddeley Proteus |year=1999 |publisher=Internal Fire Museum of Power |url=http://www.internalfire.com/modules.php?name=Content&pa=showpage&pid=136 |url-status=dead |archive-url=https://web.archive.org/web/20090118165708/http://www.internalfire.com/modules.php?name=Content&pa=showpage&pid=136 |archive-date=18 January 2009}}</ref> In its most extreme form, amateurs have even rebuilt engines beyond professional repair and then used them to compete for the land speed record.

The simplest form of self-constructed gas turbine employs an automotive [[turbocharger]] as the core component. A combustion chamber is fabricated and plumbed between the compressor and turbine sections.<ref name="Scrapheap Challenge, gas turbine go-cart" >{{cite episode|title=Jet Racer |series=Scrapheap Challenge |series-link=Scrapheap Challenge |season=6 |url= http://www.channel4.com/programmes/scrapheap-challenge/4od#3349454 |location=UK |year=2003 |access-date=13 March 2016}}</ref>

More sophisticated turbojets are also built, where their thrust and light weight are sufficient to power large model aircraft.<ref name="Schreckling, Gas Turbines for Model Aircraft" >{{cite book |last=Schreckling |first=Kurt |title=Gas Turbines for Model Aircraft |year=1994 |publisher=Traplet Publications |isbn=978-0-9510589-1-6}}</ref> The [[Kurt Schreckling|Schreckling]] design<ref name="Schreckling, Gas Turbines for Model Aircraft" /> constructs the entire engine from raw materials, including the fabrication of a [[centrifugal compressor]] wheel from plywood, epoxy and wrapped carbon fibre strands.

Several small companies now manufacture small turbines and parts for the amateur. Most turbojet-powered model aircraft are now using these commercial and semi-commercial microturbines, rather than a Schreckling-like home-build.<ref name="Kamps" >{{cite book|title=Model Jet Engines |isbn=978-1-900371-91-9 |year=2005 |last=Kamps |first=Thomas |publisher=Traplet Publications}}</ref>

===Auxiliary power units===
Small gas turbines are used as [[auxiliary power unit]]s (APUs) to supply auxiliary power to larger, mobile, machines such as an [[aircraft]], and are a [[turboshaft]] design.<ref name=":0" /> They supply:
* compressed air for [[air cycle machine]] style air conditioning and ventilation,
* compressed air start-up power for larger [[jet engine]]s,
* mechanical (shaft) power to a gearbox to drive shafted accessories, and
* electrical, hydraulic and other power-transmission sources to consuming devices remote from the APU.

===Industrial gas turbines for power generation===
[[File:Gateway Generating Station rectified.jpg|thumb|[[Gateway Generating Station]], a [[combined cycle power generation|combined-cycle]] [[gas-fired power plant|gas-fired power station]] in California, uses two GE 7F.04 combustion turbines to burn [[natural gas]].]]
[[File:GE H series Gas Turbine.jpg|thumb|GE H series power generation gas turbine: In [[combined cycle]] configuration, its highest [[thermodynamic efficiency]] is 62.22%.]]{{See also|Gas-fired power plant}}
Industrial gas turbines differ from aeronautical designs in that the frames, bearings, and blading are of heavier construction. They are also much more closely integrated with the devices they power—often an [[electric generator]]—and the secondary-energy equipment that is used to recover residual energy (largely heat).

They range in size from portable mobile plants to large, complex systems weighing more than a hundred tonnes housed in purpose-built buildings. When the gas turbine is used solely for shaft power, its thermal efficiency is about 30%. However, it may be cheaper to buy electricity than to generate it. Therefore, many engines are used in CHP (Combined Heat and Power) configurations that can be small enough to be integrated into portable [[Intermodal container|container]] configurations.

Gas turbines can be particularly efficient when [[waste heat]] from the turbine is recovered by a heat recovery steam generator (HRSG) to power a conventional steam turbine in a [[combined cycle]] configuration.<ref>{{cite web |url= http://memagazineblog.org/2012/07/01/efficiency-by-the-numbers/ |archive-url= https://web.archive.org/web/20130207053320/http://memagazineblog.org/2012/07/01/efficiency-by-the-numbers/ |url-status= dead |archive-date= 7 February 2013 |title= Efficiency by the Numbers |first=Lee S. |last=Langston |date= July 2012 }}</ref> The 605 MW [[General Electric]] 9HA achieved a 62.22% efficiency rate with temperatures as high as {{convert|2800|°F|°C|order=flip}}.<ref>{{cite press release |url=http://www.gereports.com/bouchain/ |title=Here's Why The Latest Guinness World Record Will Keep France Lit Up Long After Soccer Fans Leave |first=Tomas |last=Kellner |publisher=[[General Electric]] |date=17 June 2016 |access-date=21 June 2016 |archive-date=16 June 2017 |archive-url=https://web.archive.org/web/20170616021542/http://www.gereports.com/bouchain/ |url-status=dead }}</ref>
For 2018, GE offers its 826 MW HA at over 64% efficiency in combined cycle due to advances in [[additive manufacturing]] and combustion breakthroughs, up from 63.7% in 2017 orders and on track to achieve 65% by the early 2020s.<ref>{{cite press release |url= https://www.genewsroom.com/press-releases/ha-technology-now-available-industry-first-64-percent-efficiency-284144 |title= HA technology now available at industry-first 64 percent efficiency |date= 4 December 2017 |publisher= GE Power |access-date= 6 December 2017 |archive-date= 4 December 2018 |archive-url= https://web.archive.org/web/20181204120609/https://www.genewsroom.com/press-releases/ha-technology-now-available-industry-first-64-percent-efficiency-284144 |url-status= dead }}</ref>
In March 2018, GE Power achieved a 63.08% gross efficiency for its 7HA turbine.<ref>{{cite press release |url= https://www.ge.com/news/press-releases/ges-ha-gas-turbine-delivers-second-world-record-efficiency/ |title= GE's HA Gas Turbine Delivers Second World Record for Efficiency |publisher= GE Power |date= March 27, 2018}}</ref>

Aeroderivative gas turbines can also be used in combined cycles, leading to a higher efficiency, but it will not be as high as a specifically designed industrial gas turbine. They can also be run in a [[cogeneration]] configuration: the exhaust is used for space or water heating, or drives an [[absorption chiller]] for cooling the inlet air and increase the power output, technology known as [[turbine inlet air cooling]].

Another significant advantage is their ability to be turned on and off within minutes, supplying power during peak, or unscheduled, demand. Since single cycle (gas turbine only) power plants are less efficient than combined cycle plants, they are usually used as [[peaking power plant]]s, which operate anywhere from several hours per day to a few dozen hours per year—depending on the electricity demand and the generating capacity of the region. In areas with a shortage of base-load and [[load following power plant]] capacity or with low fuel costs, a gas turbine powerplant may regularly operate most hours of the day. A large single-cycle gas turbine typically produces 100 to 400&nbsp;megawatts of electric power and has 35–40% [[thermodynamic efficiency]].<ref name=siemens>{{cite web |first1=Phil |last1=Ratliff |first2=Paul |last2=Garbett |first3=Willibald |last3=Fischer |title=The New Siemens Gas Turbine SGT5-8000H for More Customer Benefit |work=VGB PowerTech |publisher=Siemens Power Generation |date=September 2007 |url=http://www.energy.siemens.com/us/pool/hq/power-generation/gas-turbines/downloads/SGT5-8000H_benefits.pdf |access-date=17 July 2010 |archive-date=13 August 2011 |archive-url=https://web.archive.org/web/20110813030259/http://www.energy.siemens.com/us/pool/hq/power-generation/gas-turbines/downloads/SGT5-8000H_benefits.pdf |url-status=dead }}</ref>

===Industrial gas turbines for mechanical drive===
Industrial gas turbines that are used solely for mechanical drive or used in collaboration with a recovery steam generator differ from power generating sets in that they are often smaller and feature a dual shaft design as opposed to a single shaft. The power range varies from 1 megawatt up to 50 megawatts.{{citation needed|date=December 2012}} These engines are connected directly or via a gearbox to either a pump or compressor assembly. The majority of installations are used within the oil and gas industries. Mechanical drive applications increase efficiency by around 2%.

Oil and gas platforms require these engines to drive compressors to inject gas into the wells to force oil up via another bore, or to compress the gas for transportation. They are also often used to provide power for the platform. These platforms do not need to use the engine in collaboration with a CHP system due to getting the gas at an extremely reduced cost (often free from burn off gas). The same companies use pump sets to drive the fluids to land and across pipelines in various intervals.

====Compressed air energy storage====
{{Main|Compressed air energy storage}}

One modern development seeks to improve efficiency in another way, by separating the compressor and the turbine with a compressed air store. In a conventional turbine, up to half the generated power is used driving the compressor. In a compressed air energy storage configuration, power is used to drive the compressor, and the compressed air is released to operate the turbine when required.

===Turboshaft engines===
{{Main|Turboshaft}}
[[Turboshaft]] engines are used to drive compressors in gas pumping stations and natural gas liquefaction plants. They are also used in aviation to power all but the smallest modern helicopters, and function as an [[auxiliary power unit]] in large commercial aircraft. A primary shaft carries the compressor and its turbine which, together with a combustor, is called a gas generator. A separately spinning power-turbine is usually used to drive the rotor on helicopters. Allowing the gas generator and power turbine/rotor to spin at their own speeds allows more flexibility in their design.

===Radial gas turbines===
{{Main|Radial turbine}}

===Scale jet engine===
[[File:DH Goblin annotated colour cutaway.png|thumb|Scale jet engines are scaled-down versions of this early full-scale engine.]]

A typical scale jet engine, or miniature gas turbine or micro-jet, uses a centrifugal compressor.

The pioneer of modern micro-jets, [[Kurt Schreckling]], produced one of the world's first micro-turbines, the FD3/67.<ref name="Schreckling, Gas Turbines for Model Aircraft" /> This engine can produce up to 22 [[newton (unit)|newtons]] of thrust and can be built by most mechanically minded people with basic engineering tools, such as a [[metal lathe]].<ref name="Schreckling, Gas Turbines for Model Aircraft" />

===Microturbines===
{{Main|Microturbine}}

Evolved from piston engine [[turbocharger]]s, aircraft [[auxiliary power unit|APU]]s or small [[jet engine]]s, [[microturbine]]s are 25 to 500 [[kilowatt]] turbines the size of a [[refrigerator]].<!--<ref name=wbdg22dec2016/>-->
Microturbines have around 15% [[engine efficiency|efficiencies]] without a [[recuperator]], or 20 to 30% with one, and they can reach 85% combined thermal–electrical efficiency in [[cogeneration]].<ref name=wbdg22dec2016>{{cite news |url= https://www.wbdg.org/resources/microturbines |title= Microturbines |first=Barney L. |last=Capehart |date=22 December 2016 |publisher=National Institute of Building Sciences |work=Whole Building Design Guide}}</ref>

==External combustion==
Most gas turbines are internal combustion engines but it is also possible to manufacture an external combustion gas turbine which is, effectively, a turbine version of a [[hot air engine]].
Those systems are usually indicated as EFGT (externally fired gas turbine) or IFGT (indirectly fired gas turbine).

External combustion has been used for the purpose of using [[pulverized coal]] or finely ground biomass (such as sawdust) as a fuel. In the indirect system, a [[heat exchanger]] is used and only clean air with no combustion products travels through the power turbine. The [[thermal efficiency]] is lower in the indirect type of external combustion; however, the turbine blades are not subjected to combustion products and much lower quality (and therefore cheaper) fuels are able to be used.

When external combustion is used, it is possible to use exhaust air from the turbine as the primary combustion air. This effectively reduces global heat losses, although heat losses associated with the combustion exhaust remain inevitable.

[[Closed-cycle gas turbine]]s based on [[helium]] or [[supercritical carbon dioxide]] also hold promise for use with future high temperature solar and nuclear power generation.

==In surface vehicles==
[[File:MZKT open day 2019 p06.jpg|thumb|[[MAZ-7907]], a [[transporter erector launcher]] with a [[turbine–electric powertrain]] ]]

Gas turbines are often used on [[ship]]s, [[locomotive]]s, [[helicopter]]s, and [[tank]]s and, to a lesser extent, on cars, buses, and motorcycles.

A key advantage of jets and [[turboprop]]s for airplane propulsion – their superior performance at high altitude compared to piston engines, particularly [[naturally aspirated engine|naturally aspirated]] ones – is irrelevant in most automobile applications. Their power-to-weight advantage, though less critical than for aircraft, is still important.

Gas turbines offer a high-powered engine in a very small and light package. However, they are not as responsive and efficient as small piston engines over the wide range of engine speed and power needed in vehicle applications. In [[series hybrid]] vehicles, as the driving electric motors are mechanically detached from the electricity-generating engine, the problems of responsiveness, poor performance at low speed, and low efficiency at low output are much less important. The turbine can be run at optimum speed for its power output, and batteries and [[ultracapacitor]]s can supply power as needed, with the engine cycled on and off to run it only at high efficiency. The emergence of the [[continuously variable transmission]] may also alleviate the responsiveness problem.

Turbines have historically been more expensive to produce than piston engines, though this is partly because piston engines have been mass-produced in huge quantities for decades, while small gas turbine engines are rarities; however, turbines are mass-produced in the closely related form of the [[turbocharger]].

The turbocharger is basically a compact and simple free shaft radial gas turbine which is driven by the piston engine's [[exhaust gas]]. The centripetal turbine wheel drives a centrifugal compressor wheel through a common rotating shaft. This wheel supercharges the engine air intake to a degree that can be controlled by means of a [[wastegate]] or by dynamically modifying the turbine housing's geometry (as in a [[variable geometry turbocharger]]).
It mainly serves as a power recovery device which converts a great deal of otherwise wasted thermal and kinetic energy into engine boost.

[[Turbo-compound engine]]s (actually employed on some [[semi-trailer truck]]s) are fitted with blow down turbines which are similar in design and appearance to a turbocharger except for the turbine shaft being mechanically or hydraulically connected to the engine's crankshaft instead of to a centrifugal compressor, thus providing additional power instead of boost. While the turbocharger is a pressure turbine, a power recovery turbine is a velocity one.{{citation needed|date=September 2022}}

===Passenger road vehicles (cars, bikes, and buses)===
A number of experiments have been conducted with gas turbine powered [[automobile]]s, the largest by [[Chrysler]].<ref>[http://www.turbinecar.com/misc/History.pdf "History of Chrysler Corporation Gas Turbine Vehicles"] published by the Engineering Section 1979</ref><ref>[http://automobileart.homestead.com/ChryslerConceptCars.html "Chrysler Corp., Exner Concept Cars 1940 to 1961" undated], retrieved on 11 May 2008.</ref> More recently, there has been some interest in the use of turbine engines for hybrid electric cars. For instance, a consortium led by micro gas turbine company [[Bladon Jets]] has secured investment from the Technology Strategy Board to develop an Ultra Lightweight Range Extender (ULRE) for next-generation electric vehicles. The objective of the consortium, which includes luxury car maker Jaguar Land Rover and leading electrical machine company SR Drives, is to produce the world's first commercially viable – and environmentally friendly – gas turbine generator designed specifically for automotive applications.<ref name="bladon">{{Cite web|url=https://www.bladonmt.com/news|archiveurl=https://web.archive.org/web/20120313215440/http://www.bladonjets.com/news/bladon-jets-wins-tsb-award/|url-status=dead|title=News|archivedate=13 March 2012|website=Bladon Micro Turbine}}</ref>

The common turbocharger for gasoline or diesel engines is also a turbine derivative.

====Concept cars====
[[File:Rover.jet1.jpg|thumb|The 1950 [[Rover Company|Rover]] JET1]]

The first serious investigation of using a gas turbine in cars was in 1946 when two engineers, Robert Kafka and Robert Engerstein of Carney Associates, a New York engineering firm, came up with the concept where a unique compact turbine engine design would provide power for a rear wheel drive car. After an article appeared in ''Popular Science'', there was no further work, beyond the paper stage.<ref>{{cite journal|url= https://books.google.com/books?id=7SADAAAAMBAJ&q=popular+science+May+1946&pg=PA121 |page=121 |title=Gas Turbines For Autos |date=May 1946 |journal=Popular Science |volume=146 |issue=8 |access-date=13 March 2016}}</ref>

;Early concepts (1950s/60s)
In 1950, designer F.R. Bell and Chief Engineer [[Maurice Wilks]] from British car manufacturers [[Rover Company|Rover]] unveiled the first car powered with a gas turbine engine. The two-seater [[Rover JET1|JET1]] had the engine positioned behind the seats, air intake grilles on either side of the car, and exhaust outlets on the top of the tail. During tests, the car reached top speeds of {{convert|140|km/h|mph|abbr=on}}, at a turbine speed of 50,000&nbsp;rpm. After being shown in the United Kingdom and the United States in 1950, JET1 was further developed, and was subjected to speed trials on the Jabbeke highway in Belgium in June 1952, where it exceeded {{cvt|150|mph|km/h|order=flip|round=5}}.<ref>{{cite book |last=Bobbitt |first=Malcolm |year=2007 |orig-year=1994 |chapter=III &ndash; Gas-Turbines and the Jet Era |chapter-url={{Google books|1sR68p5zDdsC|Rover P4 Series|page=71|plainurl=yes}} |title=Rover P4 Series |pages=84–87 |url={{Google books|1sR68p5zDdsC|Rover P4 Series|plainurl=yes}} |edition=revised |location=Dorchester, UK |publisher=Veloce Publishing |isbn=978-1-903706-57-2 |access-date=17 October 2014}}</ref> The car ran on [[petrol]], [[kerosene|paraffin (kerosene)]] or [[Diesel fuel|diesel]] oil, but fuel consumption problems proved insurmountable for a production car. JET1 is on display at the London [[Science Museum (London)|Science Museum]].

A French turbine-powered car, the SOCEMA-Grégoire, was displayed at the October 1952 [[Paris Auto Show]]. It was designed by the French engineer [[Jean-Albert Grégoire]].<ref name=retro05>{{cite web | url = http://www.classics.com/retro05.html | archive-url = https://web.archive.org/web/20181216115459/http://www.classics.com/retro05.html | archive-date = 2018-12-16 | title = Rétromobile 2005 | date = February 2005 | publisher = Classics.com | first = Stephane | last = Depreux }}</ref>

[[File:FirebirdI.jpg|thumb|[[General Motors Firebird|GM Firebird I]] ]]

The first turbine-powered car built in the US was the [[General Motors Firebird|GM Firebird I]] which began evaluations in 1953. While photos of the Firebird I may suggest that the jet turbine's thrust propelled the car like an aircraft, the turbine actually drove the rear wheels. The Firebird I was never meant as a commercial passenger car and was built solely for testing & evaluation as well as public relation purposes.<ref>{{cite journal| url= https://books.google.com/books?id=nNwDAAAAMBAJ&pg=PA90|title=Gas Turbine Auto |journal=Popular Mechanics |date=March 1954 |page=90 |volume=101 |issue=3}}</ref> Additional Firebird concept cars, each powered by gas turbines, were developed for the 1953, 1956 and 1959 [[General Motors Motorama|Motorama]] auto shows. The GM Research gas turbine engine also was fitted to a series of [[transit bus]]es, starting with the Turbo-Cruiser I of 1953.<ref>{{cite journal |doi=10.4271/650714 |jstor=44554219 |title=The General Motors Research GT-309 Gas Turbine Engine |first1=W.A. |last1=Turunen |first2=J.S. |last2=Collman |journal=Transactions |series=SAE Technical Paper Series |volume=74 |date=1966 |publisher=Society of Automotive Engineering |pages=357–377 |article-number=650714 }}</ref>

[[File:ChryslerTurbineEngine01 crop1.jpg|thumb|Engine compartment of a Chrysler 1963 Turbine car]]

Starting in 1954 with a modified [[Plymouth (automobile)|Plymouth]],<ref name="PS-turboPlymouth">{{cite journal|url= https://books.google.com/books?id=zSADAAAAMBAJ&pg=PA102 |title=Turbo Plymouth Threatens Future of Standard |journal=Popular Science |date=July 1954 |page=102 |volume=165 |issue=1 |access-date=13 March 2016}}</ref> the American car manufacturer [[Chrysler Corporation|Chrysler]] demonstrated several [[Chrysler Turbine engines|prototype gas turbine]]-powered cars from the early 1950s through the early 1980s. Chrysler built fifty [[Chrysler Turbine Car]]s in 1963 and conducted the only consumer trial of gas turbine-powered cars.<ref>{{cite web|url= http://www.allpar.com/mopar/turbine.html |title=Chrysler turbine engines and cars |publisher=Allpar.com |access-date=13 March 2016}}</ref> Each of their turbines employed a unique rotating [[recuperator]], referred to as a regenerator that increased efficiency.<ref name="PS-turboPlymouth"/>

In 1954, [[Fiat]] unveiled a [[concept car]] with a turbine engine, called [[Fiat Turbina]]. This vehicle, looking like an aircraft with wheels, used a unique combination of both jet thrust and the engine driving the wheels. Speeds of {{convert|175|mph|km/h|abbr=on|order=flip|round=5|0}} were claimed.<ref>{{cite journal|url= https://books.google.com/books?id=zSADAAAAMBAJ&pg=-PA20 |title=Italy's Turbo Car Hits 175 m.p.h. |journal=Popular Mechanics |date=July 1954 |page=120 |volume=165 |issue=1 |access-date=13 March 2016}}</ref>

In the 1960s, Ford and GM also were developing gas turbine semi-trucks. Ford displayed the Big Red at the [[1964 World's Fair]].<ref name=bigred3>{{cite web |url=https://www.thedrive.com/news/37925/we-found-fords-incredible-turbine-powered-semi-truck-big-red-thats-been-lost-for-decades |title=We Found Ford's Incredible Turbine-Powered Semi-Truck 'Big Red' That's Been Lost for Decades |work=The Drive |location=US |first=Peter |last=Holderith |date=24 March 2021 |access-date=27 March 2021}}</ref>  With the trailer, it was {{cvt|96|foot|m|order=flip}} long, {{cvt|13|foot|m|order=flip}} high, and painted crimson red.  It contained the Ford-developed gas turbine engine, with output power and torque of {{cvt|600|hp|kW|order=flip}} and {{cvt|855|lbft|order=flip|round=5}}.  The cab boasted a highway map of the continental U.S., a mini-kitchen, bathroom, and a TV for the co-driver.  The fate of the truck was unknown for several decades, but it was rediscovered in early 2021 in private hands, having been restored to running order.<ref>{{cite AV media |url=https://www.youtube.com/watch?v=DuGqP25jnQU | archive-url=https://ghostarchive.org/varchive/youtube/20211030/DuGqP25jnQU| archive-date=2021-10-30|title=" Big Red " Experimental Gas Turbine Semi Truck 1964 New York World's Fair XD10344 |publisher=Ford Motor Company |via=YouTube |year=1966 |access-date=4 September 2020}}{{cbignore}}</ref><ref name=bigred2>{{cite web |url=https://www.thedrive.com/news/35030/fords-giant-turbine-semi-truck-big-red-is-lost-somewhere-in-the-american-southeast |title=Ford's Giant Turbine Semi-Truck 'Big Red' Is Lost Somewhere in the American Southeast |work=The Drive |location=US |first=Peter |last=Holderith |date=19 August 2020 |access-date=21 August 2020}}</ref> The Chevrolet division of GM built the ''Turbo Titan'' series of concept trucks with turbine motors as analogs of the Firebird concepts, including Turbo Titan I ({{circa|1959}}, shares GT-304 engine with Firebird II), Turbo Titan II ({{circa|1962}}, shares GT-305 engine with Firebird III), and [[Chevrolet Turbo Titan III|Turbo Titan III]] (1965, GT-309 engine); in addition, the GM Bison gas turbine truck was shown at the 1964 World's Fair.<ref>{{cite news |url=https://www.topspeed.com/cars/guides/the-story-of-turbo-titan-chevy-s-long-lost-gas-turbine-truck/ |title=The story of Turbo Titan - Chevy's long-lost gas turbine truck |first=Iulian |last=Dnistran |date=April 20, 2021 |work=TopSpeed |access-date=12 September 2022}}</ref>

;Emissions and fuel economy (1970s/80s)
As a result of the U.S. [[Clean Air Act (United States)|Clean Air Act]] Amendments of 1970, research was funded into developing automotive gas turbine technology.<ref>{{cite book|title=Issues in Federally Supported Research on Advanced Automotive Power Systems |first1=Lawrence H. |last1=Linden |first2=Subramanyam |last2=Kumar |first3=Paul R. |last3=Samuelson |publisher=Division of Policy Research and Analysis, National Science Foundation |date=December 1977 |page=49 |hdl=1721.1/31259 }}</ref> Design concepts and vehicles were conducted by [[Chrysler]], [[General Motors]], [[Ford Motor Company|Ford]] (in collaboration with [[Garrett AiResearch|AiResearch]]), and [[American Motors]] (in conjunction with [[Williams International|Williams Research]]).<ref>Linden, page 53.</ref> Long-term tests were conducted to evaluate comparable cost efficiency.<ref>{{cite journal |last1=Verrelli |first1=L. D. |last2=Andary |first2=C. J. |title=Exhaust Emission Analysis of the Williams Research Gas Turbine AMC Hornet |journal=National Technical Information Service |date=May 1972 |id=PB218687 |osti=5038506 }}</ref> Several [[AMC Hornet]]s were powered by a small Williams regenerative gas turbine weighing {{convert|250|lb|kg|0|abbr=on}} and producing {{convert|80|hp|kW PS|0|abbr=on}} at 4450&nbsp;rpm.<ref>{{cite journal|last=Norbye |first=Jan P. |title=Tiny 80-HP gas turbine to power compact car |journal=Popular Science |date=March 1971 |volume=198 |issue=3 |url= https://books.google.com/books?id=ogAAAAAAMBAJ&q=Tiny+80-HP+gas+turbine+to+power+compact+car&pg=PA34 |page=34 |access-date=13 March 2016}}</ref><ref>{{cite journal|title=Williams Turbine Takes the Road |journal=Motor Trend |date=November 1971 |volume=23 |issue=11 |first=Karl |last=Ludvigsen |author-link=Karl Ludvigsen}}</ref><ref>{{cite journal|first1=Jan P. |last1=Norbye |first2=Jim |last2=Dunne |journal=Popular Science |date=September 1973 |page=59 |title=Gas turbine car: it's now or never |volume=302 |issue=3 |url= https://books.google.com/books?id=scA6lVmzQA8C&pg=PA56}}</ref>

In 1982, General Motors used an [[Oldsmobile Delta 88]] powered by a gas turbine using pulverised coal dust. This was considered for the United States and the western world to reduce dependence on [[1980s oil glut|middle east oil at the time]]<ref>{{cite news | url=https://www.nytimes.com/2009/01/04/automobiles/04COAL.html | title=Coal in Your Stocking? Fuel up the Cadillac! | newspaper=The New York Times | date=2 January 2009 | last1=Roy | first1=Rex }}</ref><ref>{{cite web | url=https://www.autoweek.com/car-life/but-wait-theres-more/a1812701/oldsmobile-was-powered-coal-burning-turbine-engine/ | title=This Oldsmobile was powered by a coal-burning turbine engine | work=Autoweek | date=16 January 2017 }}</ref><ref>{{cite web | url=https://drivemag.com/news/gm-made-a-coal-powered-car-in-the-80s | title=GM made a coal-powered car in the 80s | date=20 March 2018 }}</ref>

[[Toyota]] demonstrated several gas turbine powered concept cars, such as the [[Toyota Century GT45|Century gas turbine hybrid]] in 1975, the [[Toyota Sports 800#Sports 800 Gas Turbine Hybrid|Sports 800 Gas Turbine Hybrid]] in 1979 and the [[Toyota GTV|GTV]] in 1985. No production vehicles were made. The GT24 engine was exhibited in 1977 without a vehicle.

;Later development
In the early 1990s, [[Volvo]] introduced the [[Volvo ECC]] which was a gas turbine powered [[hybrid electric vehicle]].<ref>{{cite web|url=http://www.greencarreports.com/ |title=Article in Green Car |publisher=Greencar.com |date=31 October 2007 |access-date=13 August 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120813152350/http://www.greencarreports.com/ |archive-date=13 August 2012}}</ref>

In 1993, [[General Motors]] developed a gas turbine powered EV1 series [[hybrid vehicle|hybrid]]—as a prototype of the [[General Motors EV1]]. A [[Williams International]] 40&nbsp;kW turbine drove an alternator which powered the battery–electric [[powertrain]]. The turbine design included a recuperator. In 2006, GM went into the [[EcoJet concept car]] project with [[Jay Leno]].

At the [[2010 Paris Motor Show]] [[Jaguar Cars|Jaguar]] demonstrated its [[Jaguar C-X75]] concept car. This electrically powered [[supercar]] has a top speed of {{convert|204|mph|abbr=on|0}} and can go from {{convert|0|to|62|mph|abbr=on|0}} in 3.4 seconds. It uses lithium-ion batteries to power four electric motors which combine to produce 780&nbsp;bhp. It will travel {{convert|68|mi}} on a single charge of the batteries, and uses a pair of Bladon Micro Gas Turbines to re-charge the batteries extending the range to {{convert|560|mi}}.<ref>{{cite web|url= http://www.automoblog.net/2010/10/01/the-electric-cat-jaguar-c-x75-concept-supercar/ |title=The Electric Cat: Jaguar C-X75 Concept Supercar |publisher=Automoblog.net |date=1 October 2010 |first=Chris |last=Nagy |work=Automoblog |access-date=13 March 2016}}</ref>

====Racing cars====
[[File:STP Turbine.jpg|thumb|The 1967 ''STP Oil Treatment Special'' on display at the [[Indianapolis Motor Speedway]] Hall of Fame Museum, with the [[Pratt & Whitney]] gas turbine shown]]
[[File:Howmet TX Daytona.jpg|thumb|A 1968 [[Howmet TX]], the only turbine-powered race car to have won a race]]

The first race car (in concept only) fitted with a turbine was in 1955 by a US Air Force group as a hobby project with a turbine loaned them by Boeing and a race car owned by Firestone Tire & Rubber company.<ref>{{cite journal |journal=Popular Science |title=Turbine Drives Retired Racing Car |page=89 |date=June 1955 |url= https://books.google.com/books?id=biYDAAAAMBAJ&q=popular+science+1930&pg=PA89 |access-date=23 July 2018}}</ref> The first race car fitted with a turbine for the goal of actual racing was by Rover and the [[British Racing Motors|BRM]] [[Formula One]] team joined forces to produce the [[Rover-BRM]], a gas turbine powered coupe, which entered the [[1963 24 Hours of Le Mans]], driven by [[Graham Hill]] and [[Richie Ginther]]. It averaged {{convert|107.8|mph|km/h|abbr=on}} and had a top speed of {{convert|142|mph|km/h|abbr=on}}. American Ray Heppenstall joined Howmet Corporation and McKee Engineering together to develop their own gas turbine sports car in 1968, the [[Howmet TX]], which ran several American and European events, including two wins, and also participated in the [[1968 24 Hours of Le Mans]]. The cars used [[Continental Motors Company|Continental]] gas turbines, which eventually set six [[Fédération Internationale de l'Automobile|FIA]] land speed records for turbine-powered cars.<ref>{{cite web|url= http://website.lineone.net/~pete.stowe/pete_howmet.htm |title=The history of the Howmet TX turbine car of 1968, still the world's only turbine powered race winner |publisher=Pete Stowe Motorsport History |date=June 2006 |access-date=2008-01-31 |url-status=dead |archive-url= https://web.archive.org/web/20080302012133/http://website.lineone.net/~pete.stowe/pete_howmet.htm |archive-date=2 March 2008}}</ref>

For [[open wheel racing]], 1967's revolutionary [[STP-Paxton Turbocar]] fielded by racing and entrepreneurial legend [[Andy Granatelli]] and driven by [[Parnelli Jones]] nearly won the [[Indianapolis 500]]; the [[Pratt & Whitney PT6|Pratt & Whitney ST6B-62]] powered turbine car was almost a lap ahead of the second place car when a gearbox bearing failed just three laps from the finish line. The next year the STP [[Lotus 56]] turbine car won the Indianapolis 500 pole position even though new rules restricted the air intake dramatically. In 1971 [[Team Lotus]] principal [[Colin Chapman]] introduced the [[Lotus 56| Lotus 56B]] F1 car, powered by a [[Pratt & Whitney PT6|Pratt & Whitney STN 6/76]] gas turbine. Chapman had a reputation of building radical championship-winning cars, but had to abandon the project because there were too many problems with [[turbo lag]].

====Buses====
General Motors fitted the [[GM Whirlfire engine|GT-30x series of gas turbines (branded "Whirlfire")]] to several prototype buses in the 1950s and 1960s, including [[GM "old-look" transit bus#Turbo-Cruiser I|Turbo-Cruiser I]] (1953, GT-300); [[GM New Look bus#Variants based on the New Look|Turbo-Cruiser II]] (1964, GT-309); Turbo-Cruiser III (1968, GT-309); [[Rapid Transit Series|RTX]] (1968, GT-309); and [[Transbus Program|RTS 3T]] (1972).<ref>{{cite news |url=https://www.curbsideclassic.com/bus-stop-classic/bus-stop-classics-general-motors-gm-turbo-cruiser-i-ii-and-iii-urban-transit-coaches-maverick-top-gun-your-bus-is-here/ |title=Bus Stop Classics: General Motors (GM) Turbo Cruiser I, II and III Urban Transit Coaches – Maverick (Top Gun), Your Bus is Here... |first=Jim |last=Brophy |date=June 2, 2018 |website=Curbside Classic |access-date=12 September 2022}}</ref>

The arrival of the [[Capstone Turbine]] has led to several hybrid bus designs, starting with HEV-1 by AVS of Chattanooga, Tennessee in 1999, and closely followed by Ebus and ISE Research in California, and [[DesignLine Corporation]] in New Zealand (and later the United States). AVS turbine hybrids were plagued with reliability and quality control problems, resulting in liquidation of AVS in 2003. The most successful design by Designline is now operated in 5 cities in 6 countries, with over 30 buses in operation worldwide, and order for several hundred being delivered to Baltimore, and New York City.

[[Brescia|Brescia Italy]] is using serial hybrid buses powered by microturbines on routes through the historical sections of the city.<ref name="Source">{{cite web |url=http://draft.fgm-amor.at/altermotive/study_sheet.phtml?study_id=2866&lang1=en |title=Serial Hybrid Busses for a Public Transport scheme in Brescia (Italy) |publisher=Draft.fgm-amor.at |access-date=13 August 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120316112717/http://draft.fgm-amor.at/altermotive/study_sheet.phtml?study_id=2866&lang1=en |archive-date=16 March 2012}}</ref>

====Motorcycles====
The [[MTT Turbine Superbike]] appeared in 2000 (hence the designation of Y2K Superbike by MTT) and is the first production motorcycle powered by a turbine engine – specifically, a Rolls-Royce Allison model 250 turboshaft engine, producing about 283&nbsp;kW (380&nbsp;bhp). Speed-tested to 365&nbsp;km/h or 227&nbsp;mph (according to some stories, the testing team ran out of road during the test), it holds the Guinness World Record for most powerful production motorcycle and most expensive production motorcycle, with a price tag of US$185,000.

===Trains===
{{Main|Gas turbine locomotive}}

Several locomotive classes have been powered by gas turbines, the most recent incarnation being [[Bombardier Transportation|Bombardier]]'s [[JetTrain]].

===Tanks===
[[File:AGT1500 engine and M1 tank.JPEG|thumb|Marines from 1st Tank Battalion load a [[Honeywell AGT1500]] multi-fuel turbine back into an M1 Abrams tank at Camp Coyote, Kuwait, February 2003]]

The Third Reich [[German Army (Wehrmacht)|''Wehrmacht Heer'']]'s development division, the [[Heereswaffenamt]] (Army Ordnance Board), studied a number of gas turbine engine designs for use in tanks starting in mid-1944. The first gas turbine engine design intended for use in armored fighting vehicle propulsion, the [[BMW 003]]-based [[GT 101]], was meant for installation in the [[Panther tank]].<ref>{{cite book |last=Kay |first=Antony L. |title=German jet engine and gas turbine development 1930 – 1945 |year=2002 |publisher=Airlife |isbn=9781840372946}}</ref>  Towards the end of the war, a [[Jagdtiger]] was fitted with one of the aforementioned gas turbines.<ref>{{cite web |last=Fletcher |first=David |url=https://tankmuseum.org/article/gas-turbine-jagdtiger |title=Gas Turbine Jagdtiger |publisher=tankmuseum.org |year=2017}}</ref>

The second use of a gas turbine in an armored fighting vehicle was in 1954 when a unit, PU2979, specifically developed for tanks by [[C. A. Parsons and Company]], was installed and trialed in a British [[Conqueror tank]].<ref>{{cite book |last=Ogorkiewicz |first=Richard M. |title=Technology of Tanks |url=https://archive.org/details/Janes_Technology_of_Tanks_01 |page=[https://archive.org/details/Janes_Technology_of_Tanks_01/page/n272 259] |year=1991 |publisher=Jane's Information Group |isbn=9780710605955}}</ref> The [[Stridsvagn 103]] was developed in the 1950s and was the first mass-produced main battle tank to use a turbine engine, the [[Boeing T50]]. Since then, gas turbine engines have been used as [[auxiliary power unit]]s in some tanks and as main powerplants in Soviet/Russian [[T-80]]s and U.S. [[M1 Abrams]] tanks, among others. They are lighter and smaller than [[diesel engine]]s at the same sustained power output but the models installed to date are less fuel efficient than the equivalent diesel, especially at idle, requiring more fuel to achieve the same combat range. Successive models of M1 have addressed this problem with battery packs or secondary generators to power the tank's systems while stationary, saving fuel by reducing the need to idle the main turbine. T-80s can mount three large external fuel drums to extend their range. Russia has stopped production of the T-80 in favor of the diesel-powered [[T-90]] (based on the [[T-72]]), while Ukraine has developed the diesel-powered T-80UD and T-84 with nearly the power of the gas-turbine tank. The French [[Leclerc tank]]'s diesel powerplant features the "Hyperbar" hybrid supercharging system, where the engine's turbocharger is completely replaced with a small gas turbine which also works as an assisted diesel exhaust turbocharger, enabling engine RPM-independent boost level control and a higher peak boost pressure to be reached (than with ordinary turbochargers). This system allows a smaller displacement and lighter engine to be used as the tank's power plant and effectively removes [[turbo lag]]. This special gas turbine/turbocharger can also work independently from the main engine as an ordinary APU.

A turbine is theoretically more reliable and easier to maintain than a piston engine since it has a simpler construction with fewer moving parts, but in practice, turbine parts experience a higher wear rate due to their higher working speeds. The turbine blades are highly sensitive to dust and fine sand so that in desert operations air filters have to be fitted and changed several times daily. An improperly fitted filter, or a bullet or shell fragment that punctures the filter, can damage the engine. Piston engines (especially if turbocharged) also need well-maintained filters, but they are more resilient if the filter does fail.

Like most modern diesel engines used in tanks, gas turbines are usually multi-fuel engines.

==Marine applications==
{{main|Marine propulsion}}

===Naval===
[[File:Gas turbine from MGB 2009.jpg|thumb|The gas turbine from MGB 2009]]

Gas turbines are used in many [[naval vessel]]s, where they are valued for their high [[power-to-weight ratio]] and their ships' resulting acceleration and ability to get underway quickly.

The first gas-turbine-powered naval vessel was the [[Royal Navy]]'s [[motor gunboat]] ''MGB 2009'' (formerly ''MGB 509'') converted in 1947. [[Metropolitan-Vickers]] fitted their [[Metropolitan-Vickers F.2|F2/3]] jet engine with a power turbine. The [[Steam Gun Boat]] ''Grey Goose'' was converted to Rolls-Royce gas turbines in 1952 and operated as such from 1953.<ref name="Walsh_01">{{cite book|title=Gas Turbine Performance|first1=Philip P.|last1=Walsh|first2=Paul|last2=Fletcher|publisher=John Wiley and Sons|year=2004|isbn=978-0-632-06434-2|edition=2nd|page=25}}<!--|access-date=2011-09-15--></ref> The [[Bold class patrol boat|Bold class]] [[Fast Patrol Boat]]s ''Bold Pioneer'' and ''Bold Pathfinder'' built in 1953 were the first ships created specifically for gas turbine propulsion.<ref>{{cite web|url=http://www.scienceandsociety.co.uk/results.asp?image=10421693 |title=''The first marine gas turbine, 1947'' |publisher=Scienceandsociety.co.uk |date=23 April 2008 |access-date=13 August 2012}}</ref>

The first large-scale, partially gas-turbine powered ships were the Royal Navy's [[Tribal-class frigate|Type 81]] (Tribal class) [[frigate]]s with [[combined steam and gas]] powerplants. The first, {{HMS|Ashanti|F117|6}} was commissioned in 1961.

The [[German Navy]] launched the first {{sclass|Köln|frigate}} in 1961 with 2 [[Brown, Boveri & Cie]] gas turbines in the world's first [[combined diesel and gas]] propulsion system.

The [[Soviet Navy]] commissioned in 1962 the first of 25 {{sclass|Kashin|destroyer}} with 4 gas turbines in [[combined gas and gas]] propulsion system. Those vessels used 4 M8E gas turbines, which generated {{cvt|72000-96000|hp|kW|order=flip}}. Those ships were the first large ships in the world to be powered solely by gas turbines.

[[File:Smetlivyy2003.jpg|thumb|Project 61 large ASW ship, {{sclass|Kashin|destroyer}}]]

The [[Danish Navy]] had 6 ''Søløven''-class torpedo boats (the export version of the British [[Brave class fast patrol boat]]) in service from 1965 to 1990, which had 3 [[Bristol Proteus]] (later RR Proteus) Marine Gas Turbines rated at {{convert|12750|shp|abbr=on|order=flip|-1}} combined, plus two [[General Motors]] Diesel engines, rated at {{convert|460|shp|abbr=on|order=flip|-1}}, for better fuel economy at slower speeds.<ref>{{Cite web|url=http://www.navalhistory.dk/danish/Skibene/Skibsklasser/Soeloeven_klassen(1965).htm|archiveurl=https://web.archive.org/web/20111115094226/http://www.navalhistory.dk/danish/Skibene/Skibsklasser/Soeloeven_klassen%281965%29.htm|url-status=dead|title=''Søløven class torpedoboat, 1965''|archivedate=15 November 2011}}</ref> And they also produced 10 Willemoes Class Torpedo / Guided Missile boats (in service from 1974 to 2000) which had 3 [[Rolls-Royce plc|Rolls-Royce]] Marine Proteus Gas Turbines also rated at {{convert|12750|shp|abbr=on|order=flip|-1}}, same as the Søløven-class boats, and 2 General Motors Diesel Engines, rated at {{convert|800|shp|abbr=on|order=flip|-1}}, also for improved fuel economy at slow speeds.<ref>{{Cite web|url=http://www.navalhistory.dk/english/TheShips/Classes/Willemoes_Class(1977).htm|archiveurl=https://web.archive.org/web/20110820100754/http://www.navalhistory.dk/english/TheShips/Classes/Willemoes_Class%281977%29.htm|url-status=dead|title=''Willemoes class torpedo/guided missile boat, 1974''|archivedate=20 August 2011}}</ref>

The [[Swedish Navy]] produced 6 Spica-class torpedo boats between 1966 and 1967 powered by 3 [[Bristol Siddeley]] [[Bristol Proteus|Proteus 1282 turbines]], each delivering {{convert|4300|shp|abbr=on|order=flip|-1}}. They were later joined by 12 upgraded Norrköping class ships, still with the same engines. With their aft torpedo tubes replaced by antishipping missiles they served as missile boats until the last was retired in 2005.<ref>[[w:sv:Robotbåt|Fast missile boat]]</ref>

The [[Finnish Navy]] commissioned two {{sclass|Turunmaa|gunboat|0}} [[corvette]]s, ''Turunmaa'' and ''Karjala'', in 1968. They were equipped with one {{convert|22000|shp|abbr=on|order=flip|-1}} [[Rolls-Royce Olympus]] TM1 gas turbine and three [[Wärtsilä]] marine diesels for slower speeds. They were the fastest vessels in the Finnish Navy; they regularly achieved speeds of 35 knots, and 37.3 knots during sea trials. The ''Turunmaa''s were decommissioned in 2002. ''Karjala'' is today a [[museum ship]] in [[Turku]], and ''Turunmaa'' serves as a floating machine shop and training ship for Satakunta Polytechnical College.

The next series of major naval vessels were the four Canadian {{sclass|Iroquois|destroyer|0}} helicopter carrying destroyers first commissioned in 1972. They used 2&nbsp;ft-4 main propulsion engines, 2&nbsp;ft-12 cruise engines and 3 Solar Saturn 750&nbsp;kW generators.

[[File:USS Ford (FFG-54) Gas Turbine.jpg|thumb|An LM2500 gas turbine on {{USS|Ford|FFG-54|6}}]]
The first U.S. gas-turbine powered ship was the [[United States Coast Guard|U.S. Coast Guard's]] {{USCGC|Point Thatcher|WPB-82314|2}}, a cutter commissioned in 1961 that was powered by two {{convert|1000|shp|abbr=on|order=flip|-1}} turbines utilizing controllable-pitch propellers.<ref>{{cite web|url=http://www.uscg.mil/history/webcutters/Point_Thatcher.pdf |title=US Coast Guard Historian's website, USCGC ''Point Thatcher'' (WPB-82314) |access-date=13 August 2012}}</ref> The larger {{sclass|Hamilton|cutter|0}} [[USCG high endurance cutter|High Endurance Cutters]], was the first class of larger cutters to utilize gas turbines, the first of which ({{USCGC|Hamilton|WHEC-715|6}}) was commissioned in 1967. Since then, they have powered the [[United States Navy|U.S. Navy's]] {{sclass|Oliver Hazard Perry|frigate|1}}s, {{sclass|Spruance|destroyer|5}} and {{sclass|Arleigh Burke|destroyer|2}}s, and {{sclass|Ticonderoga|cruiser|0}} [[guided missile cruisers]]. {{USS|Makin Island|LHD-8|6}}, a modified {{sclass|Wasp|amphibious assault ship}}, is to be the Navy's first amphibious assault ship powered by gas turbines.
The marine gas turbine operates in a more corrosive atmosphere due to the presence of sea salt in air and fuel and use of cheaper fuels.

===Civilian maritime===
Up to the late 1940s, much of the progress on marine gas turbines all over the world took place in design offices and engine builder's workshops and development work was led by the British [[Royal Navy]] and other Navies. While interest in the gas turbine for marine purposes, both naval and mercantile, continued to increase, the lack of availability of the results of operating experience on early gas turbine projects limited the number of new ventures on seagoing commercial vessels being embarked upon.

In 1951, the diesel–electric oil tanker ''Auris'', 12,290 [[deadweight tonnage]] (DWT) was used to obtain operating experience with a main propulsion gas turbine under service conditions at sea and so became the first ocean-going merchant ship to be powered by a gas turbine. Built by [[Hawthorn Leslie and Company|Hawthorn Leslie]] at [[Hebburn-on-Tyne]], UK, in accordance with plans and specifications drawn up by the [[Anglo-Saxon Petroleum Company]] and launched on the UK's [[Elizabeth II|Princess Elizabeth]]'s 21st birthday in 1947, the ship was designed with an engine room layout that would allow for the experimental use of heavy fuel in one of its high-speed engines, as well as the future substitution of one of its diesel engines by a gas turbine.<ref>{{Cite journal | doi=10.1111/j.1559-3584.1954.tb03976.x|title = Operation of a Marine Gas Turbine Under Sea Conditions|journal = Journal of the American Society for Naval Engineers| volume=66| issue=2| pages=457–466|year = 2009}}</ref> The ''Auris'' operated commercially as a tanker for three-and-a-half years with a diesel–electric propulsion unit as originally commissioned, but in 1951 one of its four {{convert|1105|bhp|kW|abbr=on|order=flip}} diesel engines – which were known as "Faith", "Hope", "Charity" and "Prudence" – was replaced by the world's first marine gas turbine engine, a {{convert|1200|bhp|kW|abbr=on|order=flip}} open-cycle gas turbo-alternator built by [[British Thomson-Houston|British Thompson-Houston Company]] in [[Rugby, Warwickshire|Rugby]]. Following successful sea trials off the Northumbrian coast, the ''Auris'' set sail from Hebburn-on-Tyne in October 1951 bound for [[Port Arthur, Texas|Port Arthur]] in the US and then [[Curaçao]] in the southern Caribbean returning to [[Avonmouth]] after 44 days at sea, successfully completing her historic trans-Atlantic crossing. During this time at sea the gas turbine burnt diesel fuel and operated without an involuntary stop or mechanical difficulty of any kind. She subsequently visited Swansea, Hull, [[Rotterdam]], [[Oslo]] and Southampton covering a total of 13,211 nautical miles. The ''Auris'' then had all of its power plants replaced with a {{convert|5250|shp|kW|abbr=on|order=flip}} directly coupled gas turbine to become the first civilian ship to operate solely on gas turbine power.

Despite the success of this early experimental voyage the gas turbine did not replace the diesel engine as the propulsion plant for large merchant ships. At constant cruising speeds the diesel engine simply had no peer in the vital area of fuel economy. The gas turbine did have more success in Royal Navy ships and the other naval fleets of the world where sudden and rapid changes of speed are required by warships in action.<ref>{{cite book|title=Future Ship Powering Options: Exploring alternative methods of ship propulsion|publisher=Royal Academy of Engineering Prince Philip House|isbn=9781909327016|url=http://www.raeng.org.uk/publications/reports/future-ship-powering-options|year=2013}}</ref>

The [[United States Maritime Commission]] were looking for options to update WWII [[Liberty ships]], and heavy-duty gas turbines were one of those selected. In 1956 the ''John Sergeant'' was lengthened and equipped with a [[General Electric]] {{convert|6600|shp|kW|abbr=on|order=flip}} HD gas turbine with exhaust-gas regeneration, reduction gearing and a [[Variable-pitch propeller (marine)|variable-pitch propeller]]. It operated for 9,700 hours using residual fuel ([[Bunker C]]) for 7,000 hours. [[Fuel efficiency]] was on a par with steam propulsion at {{convert|0.523|lb/hp|abbr=on|order=flip}} per hour,<ref name="IMGT">Naval Education and Training Program Development Center ''Introduction to Marine Gas Turbines'' (1978) Naval Education and Training Support Command, pp. 3.</ref> and power output was higher than expected at {{convert|7514|shp|kW|abbr=on|order=flip}} due to the ambient temperature of the North Sea route being lower than the design temperature of the gas turbine. This gave the ship a speed capability of 18 knots, up from 11 knots with the original power plant, and well in excess of the 15 knot targeted. The ship made its first transatlantic crossing with an average speed of 16.8 knots, in spite of some rough weather along the way. Suitable Bunker C fuel was only available at limited ports because the quality of the fuel was of a critical nature. The fuel oil also had to be treated on board to reduce contaminants and this was a labor-intensive process that was not suitable for automation at the time. Ultimately, the variable-pitch propeller, which was of a new and untested design, ended the trial, as three consecutive annual inspections revealed stress-cracking. This did not reflect poorly on the marine-propulsion gas-turbine concept though, and the trial was a success overall. The success of this trial opened the way for more development by GE on the use of HD gas turbines for marine use with heavy fuels.<ref name="Innovation">National Research Council (U.S.) ''Innovation in the Maritime Industry'' (1979) Maritime Transportation Research Board, pp. 127–131</ref> The ''John Sergeant'' was scrapped in 1972 at Portsmouth PA.

[[File:20091105-TurboJET Urzela.jpg|thumb|Boeing Jetfoil 929-100-007 ''Urzela'' of [[TurboJET]] ]]
[[Boeing]] launched its first passenger-carrying [[Pump-jet|waterjet]]-propelled [[hydrofoil]] [[Boeing 929]], in April 1974. Those ships were powered by two [[Allison 501]]-KF gas turbines.<ref>{{cite web |url= http://www.boeing.com/history/products/jetfoil-hydrofoil.page |title= Jetfoil/hydrofoil Historical Snapshot |publisher= Boeing}}</ref>

Between 1971 and 1981, [[Seatrain Lines]] operated a scheduled [[intermodal container|container]] service between ports on the eastern seaboard of the United States and ports in northwest Europe across the North Atlantic with four container ships of 26,000 tonnes DWT. Those ships were powered by twin [[Pratt & Whitney]] gas turbines of the FT 4 series. The four ships in the class were named ''Euroliner'', ''Eurofreighter'', ''Asialiner'' and ''Asiafreighter''. Following the dramatic [[Organization of the Petroleum Exporting Countries]] (OPEC) price increases of the mid-1970s, operations were constrained by rising fuel costs. Some modification of the engine systems on those ships was undertaken to permit the burning of a lower grade of fuel (i.e., [[Marine diesel oil|marine diesel]]). Reduction of fuel costs was successful using a different untested fuel in a marine gas turbine but maintenance costs increased with the fuel change. After 1981 the ships were sold and refitted with, what at the time, was more economical diesel-fueled engines but the increased engine size reduced cargo space.{{citation needed|date=December 2012}}

The first passenger ferry to use a gas turbine was the [[GTS Finnjet|GTS ''Finnjet'']], built in 1977 and powered by two [[Pratt & Whitney]] FT 4C-1 DLF turbines, generating {{convert|55000|kW|shp|abbr=on}} and propelling the ship to a speed of 31&nbsp;knots. However, the Finnjet also illustrated the shortcomings of gas turbine propulsion in commercial craft, as high fuel prices made operating her unprofitable. After four years of service, additional diesel engines were installed on the ship to reduce running costs during the off-season. The Finnjet was also the first ship with a [[combined diesel–electric and gas]] propulsion. Another example of commercial use of gas turbines in a passenger ship is [[Stena Line]]'s [[High-speed Sea Service|HSS class]] fastcraft ferries. HSS 1500-class ''Stena Explorer'', ''Stena Voyager'' and ''Stena Discovery'' vessels use [[combined gas and gas]] setups of twin [[General Electric|GE]] [[General Electric LM2500|LM2500]] plus GE LM1600 power for a total of {{convert|68000|kW|shp|abbr=on}}. The slightly smaller HSS 900-class ''Stena Carisma'', uses twin [[Asea Brown Boveri|ABB]]–[[STAL]] GT35 turbines rated at {{convert|34000|kW|shp|abbr=on}} gross. The ''Stena Discovery'' was withdrawn from service in 2007, another victim of too high fuel costs.{{citation needed|date=December 2012}}

In July 2000, the [[Millennium (ship)|''Millennium'']] became the first [[cruise ship]] to be powered by both gas and steam turbines. The ship featured two General Electric LM2500 gas turbine generators whose exhaust heat was used to operate a steam turbine generator in a [[COGES]] (combined gas electric and steam) configuration. Propulsion was provided by two electrically driven Rolls-Royce Mermaid azimuth pods. The liner {{RMS|Queen Mary 2}} uses a combined diesel and gas configuration.<ref>{{cite web |url=http://www.geae.com/aboutgeae/presscenter/marine/marine_20040316.html |title=GE – Aviation: GE Goes from Installation to Optimized Reliability for Cruise Ship Gas Turbine Installations |publisher=Geae.com |date=16 March 2004 |access-date=13 August 2012 |url-status=dead |archive-url=https://web.archive.org/web/20110416025534/http://www.geae.com/aboutgeae/presscenter/marine/marine_20040316.html |archive-date=16 April 2011}}</ref>

In marine racing applications the 2010 C5000 Mystic catamaran [[Miss GEICO]] uses two Lycoming T-55 turbines for its power system.{{citation needed|date=December 2012}}

==Advances in technology==
Gas turbine technology has steadily advanced since its inception and continues to evolve. Development is actively producing both smaller gas turbines and more powerful and efficient engines. Aiding in these advances are computer-based design (specifically [[computational fluid dynamics]] and [[finite element analysis]]) and the development of advanced materials: Base materials with superior high-temperature strength (e.g., [[single-crystal]] [[superalloy]]s that exhibit [[yield strength anomaly]]) or [[thermal barrier coatings]] that protect the structural material from ever-higher temperatures. These advances allow higher [[compression ratio]]s and turbine inlet temperatures, more efficient combustion and better cooling of engine parts.

[[Computational fluid dynamics]] (CFD) has contributed to substantial improvements in the performance and efficiency of gas turbine engine components through enhanced understanding of the complex viscous flow and heat transfer phenomena involved. For this reason, CFD is one of the key computational tools used in design and development of gas<ref>{{cite web |url=http://www.hcltech.com/sites/default/files/CFD_for_Aero_Engines.pdf |title=CFD for Aero Engines |publisher=HCL Technologies |date=April 2011 |access-date=13 March 2016 |archive-date=9 July 2017 |archive-url=https://web.archive.org/web/20170709034400/https://www.hcltech.com/sites/default/files/CFD_for_Aero_Engines.pdf |url-status=dead }}</ref><ref>{{Cite journal|last1=Chrystie|first1=R|last2=Burns|first2=I|last3=Kaminski|first3=C|date=2013|title=Temperature Response of an Acoustically Forced Turbulent Lean Premixed Flame: A Quantitative Experimental Determination|journal=Combustion Science and Technology|volume=185|pages=180–199|doi=10.1080/00102202.2012.714020|s2cid=46039754}}</ref> turbine engines.

The simple-cycle efficiencies of early gas turbines were practically doubled by incorporating inter-cooling, regeneration (or recuperation), and reheating. These improvements, of course, come at the expense of increased initial and operation costs, and they cannot be justified unless the decrease in fuel costs offsets the increase in other costs. The relatively low fuel prices, the general desire in the industry to minimize installation costs, and the tremendous increase in the simple-cycle efficiency to about 40 percent left little desire for opting for these modifications.<ref>{{cite book |last1=Çengel |first1=Yunus A. |first2=Michael A. |last2=Boles. |title=9-8. Thermodynamics: An Engineering Approach |edition= 7th |location=New York |publisher=McGraw-Hill |year=2011 |page=510}}</ref>

On the emissions side, the challenge is to increase turbine inlet temperatures while at the same time reducing peak flame temperature in order to achieve lower NOx emissions and meet the latest emission regulations. In May 2011, [[Mitsubishi Heavy Industries]] achieved a turbine inlet temperature of {{cvt|1600|C|F|round=50}} on a 320 megawatt gas turbine, and 460 MW in gas turbine [[combined-cycle]] power generation applications in which gross [[thermal efficiency]] exceeds 60%.<ref>{{cite web |title=MHI Achieves 1,600&nbsp;°C Turbine Inlet Temperature in Test Operation of World's Highest Thermal Efficiency "J-Series" Gas Turbine |publisher=Mitsubishi Heavy Industries |date=26 May 2011 |url= http://www.mhi.co.jp/en/news/story/1105261435.html |archive-url= https://web.archive.org/web/20131113162749/http://www.mhi.co.jp/en/news/story/1105261435.html |archive-date=2013-11-13}}</ref><ref>{{cite tech report |url=https://asmedigitalcollection.asme.org/GT/proceedings-abstract/GT2012/44694/599/289409?redirectedFrom=PDF |title=Evolution and Future Trend of Large Frame Gas Turbines: A New 1600 Degree C, J Class Gas Turbine |first1=Satoshi |last1=Hada |first2=Masanori |last2=Yuri |first3=Junichiro |last3=Masada |first4=Eisaku |last4=Ito |first5=Keizo |last5=Tsukagoshi |publisher=The American Society of Mechanical Engineers |doi=10.1115/GT2012-68574 |date=2013-07-09 |access-date=2023-12-23 |url-access=subscription}}</ref>

Compliant [[foil bearing]]s were commercially introduced to gas turbines in the 1990s. These can withstand over a hundred thousand start/stop cycles and have eliminated the need for an oil system. The application of microelectronics and [[power switching]] technology have enabled the development of commercially viable electricity generation by microturbines for distribution and vehicle propulsion.

In 2013, General Electric started the development of the [[GE9X]] with a compression ratio of 61:1.<ref>{{cite web|url=https://www.flightglobal.com/analysis-ge-opens-five-year-development-effort-for-777x-engine/109167.article|title=ANALYSIS: GE opens five-year development effort for 777X engine|first=Stephen|last=Trimble|date=2013-03-22|website=Flight Global}}</ref>

==Advantages and disadvantages==
{{pro and con list|section|date=June 2022}}

The following are advantages and disadvantages of gas-turbine engines:<ref>{{cite web|last=Brain |first=Marshall |url= http://science.howstuffworks.com/turbine2.htm |title=How Gas Turbine Engines Work |publisher=Science.howstuffworks.com |date=1 April 2000 |access-date=13 March 2016}}</ref>

Advantages include:

* Very high [[power-to-weight ratio]] compared to reciprocating engines.
* Smaller than most reciprocating engines of the same power rating.
* Smooth rotation of the main shaft produces far less vibration than a reciprocating engine.
* Fewer moving parts than reciprocating engines results in lower maintenance cost and higher reliability/availability over its service life.
* Greater reliability, particularly in applications where sustained high power output is required.
* Waste heat is dissipated almost entirely in the exhaust. This results in a high-temperature exhaust stream that is very usable for boiling water in a [[combined cycle]], or for [[cogeneration]].
* Lower peak combustion pressures than reciprocating engines in general.
* High shaft speeds in smaller "free turbine units", although larger gas turbines employed in power generation operate at synchronous speeds.
* Low lubricating oil cost and consumption.
* Can run on a wide variety of fuels.
* Very low toxic emissions of CO and HC due to excess air, complete combustion and no "quench" of the flame on cold surfaces.

Disadvantages include:

* Core engine costs can be high due to the use of exotic materials, especially in applications where high reliability is required (e.g. aircraft propulsion)
* Less efficient than reciprocating engines at idle speed.
* Longer startup than reciprocating engines.
* Less responsive to changes in power demand compared with reciprocating engines.
* Characteristic whine can be hard to suppress.  The exhaust (particularly on turbojets) can also produce a distinctive roaring sound.

==Major manufacturers==

{{colbegin}}
* [[Aero Engine Corporation of China]] (AECC)
* [[Alstom]]
* [[Ansaldo Energia]] 
* [[Bharat Heavy Electricals Limited]] (BHEL)
* [[Doosan Enerbility]]
* [[GE Aerospace]]
* [[GE Vernova]]
* [[ Hanwha Aerospace]]
* [[Harbin Electric]]
* [[Hindustan Aeronautics Limited]]
* [[Howmet Aerospace]]
* [[IHI Corporation]]
* [[Kawasaki Heavy Industries]]
* [[MAN Turbo]]
* [[MAPNA Group]]
* [[Mitsubishi Heavy Industries]] 
* [[MTU Aero Engines]]
* [[Rolls-Royce Holdings]]
* [[Power Machines]] (Silmash)
* [[Pratt & Whitney]]
* [[Pratt & Whitney Canada]]
* [[Shanghai Electric]]
* [[Siemens Energy]] 
* [[Solar Turbines]]
* [[United Engine Corporation]] (ODK)
* [[Zorya-Mashproekt]]
{{colend}}

==Testing==
British, German, other national and international test codes are used to standardize the procedures and definitions used to test gas turbines. Selection of the test code to be used is an agreement between the purchaser and the manufacturer, and has some significance to the design of the turbine and associated systems. In the United States, [[ASME]] has produced several performance test codes on gas turbines. This includes ASME PTC 22–2014. These ASME performance test codes have gained international recognition and acceptance for testing gas turbines. The single most important and differentiating characteristic of ASME performance test codes, including PTC 22, is that the test uncertainty of the measurement indicates the quality of the test and is not to be used as a commercial tolerance.

==See also==
{{colbegin}}
* [[List of aircraft engines]]
* [[Centrifugal compressor]]
* [[Gas turbine modular helium reactor]]
* [[Rotating detonation engine]]
* [[Pneumatic motor]]
* [[Pulsejet]]
* [[Steam turbine]]
* [[Turbine engine failure]]
* [[Wind turbine]]
{{colend}}

==References==
{{reflist}}

==Further reading==
* [https://web.archive.org/web/20110317172825/http://articles.compressionjobs.com/articles/oilfield-101/168-gas-turbines-principles-lube-control-systems-overspeed Stationary Combustion Gas Turbines including Oil & Over-Speed Control System description]
*"Aircraft Gas Turbine Technology" by Irwin E. Treager, McGraw-Hill, Glencoe Division, 1979, {{ISBN|0-07-065158-2}}.
*"Gas Turbine Theory" by H.I.H. Saravanamuttoo, G.F.C. Rogers and H. Cohen, Pearson Education, 2001, 5th ed., {{ISBN|0-13-015847-X}}.
*{{cite book|last1= Leyes II |first1= Richard A. |first2=William A. |last2=Fleming |title= The History of North American Small Gas Turbine Aircraft Engines |publisher=Smithsonian Institution |location= Washington, DC |year= 1999 |isbn= 978-1-56347-332-6 }}
*[https://web.archive.org/web/20070930201550/http://www.sae.org/technical/papers/2006-01-3055 R. M. "Fred" Klaass and Christopher DellaCorte, "The Quest for Oil-Free Gas Turbine Engines," SAE Technical Papers, No. 2006-01-3055, available at sae.org]
*"Model Jet Engines" by Thomas Kamps {{ISBN|0-9510589-9-1}} Traplet Publications
*''Aircraft Engines and Gas Turbines'', Second Edition by Jack L. Kerrebrock, The MIT Press, 1992, {{ISBN|0-262-11162-4}}.
* [https://web.archive.org/web/20110714104428/http://mmengineering.com/pdf%20files/Vol.%2008%2C%20No.3.pdf "Forensic Investigation of a Gas Turbine Event"] by John Molloy, M&M Engineering
*"[http://eu.wiley.com/WileyCDA/WileyTitle/productCd-063206434X.html Gas Turbine Performance, 2nd Edition" by Philip Walsh and Paul Fletcher, Wiley-Blackwell, 2004] {{ISBN|978-0-632-06434-2}}
*{{cite report|author=<!-- none given -->|year=2020|title=Advanced Technologies for Gas Turbines|place=Washington, DC|publisher=The National Academies Press|doi=10.17226/25630|isbn=978-0-309-66422-6 }}

==External links==
{{Commons category|Gas turbines (gas-based turbomachinery)|Gas turbines}}
*{{cite magazine |magazine=Popular Science |first=Alden P. |last=Armagnac |title=New Era In Power To Turn Wheels |url={{Google books|id=WCwDAAAAMBAJ|page=81|plain-url=yes}} |date=December 1939 |page=81}}
*[http://www.techzoom.net/papers/innovation_in_civil_jet_aviation_2006.pdf Technology Speed of Civil Jet Engines] {{Webarchive|url=https://web.archive.org/web/20101231113229/http://www.techzoom.net/papers/innovation_in_civil_jet_aviation_2006.pdf |date=31 December 2010 }}
*[http://web.mit.edu/aeroastro/faculty/labs.html MIT Gas Turbine Laboratory] {{Webarchive|url=https://web.archive.org/web/20100721181002/http://web.mit.edu/aeroastro/faculty/labs.html |date=21 July 2010 }}
*[https://web.archive.org/web/20090411143933/http://www.memagazine.org/backissues/membersonly/october97/features/turbdime/turbdime.html MIT Microturbine research]
*[https://web.archive.org/web/20081225002742/http://www.energy.ca.gov/distgen/equipment/microturbines/microturbines.html California Distributed Energy Resource guide – Microturbine generators]
*[http://travel.howstuffworks.com/turbine.htm Introduction to how a gas turbine works from "how stuff works.com"] {{Webarchive|url=https://web.archive.org/web/20080616043527/http://travel.howstuffworks.com/turbine.htm |date=16 June 2008 }}
*[https://web.archive.org/web/20071016062506/http://www.soton.ac.uk/~ge102/Jet.html Aircraft gas turbine simulator for interactive learning]
*[http://www.netl.doe.gov/research/coal/energy-systems/turbines/publications/handbook An online handbook on stationary gas turbine technologies compiled by the US DOE.] {{Webarchive|url=https://web.archive.org/web/20170701205000/https://www.netl.doe.gov/research/coal/energy-systems/turbines/publications/handbook |date=1 July 2017 }}
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