# Jet aircraft > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Jet_aircraft > Markdown URL: https://mediated.wiki/source/Jet_aircraft.md > Source: https://en.wikipedia.org/wiki/Jet_aircraft > Source revision: 1350880429 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{redirect|Jet plane|the Rumania Montevideo album|Jet Plane}} {{short description|Aircraft class powered by jet propulsion engines}} {{More citations needed|date=April 2026}} [[File:BEA de Havilland DH-106 Comet 4B Berlin.jpg|thumb|A [British European Airways](/source/British_European_Airways) de Havilland Comet, the world's first jet airliner entered service in 1952, this later Comet 4B shown in 1969]] A '''jet aircraft''' (or simply '''jet''') is an [aircraft](/source/aircraft) propelled by one or more [jet engine](/source/jet_engine)s. Jets are nearly always [fixed-wing aircraft](/source/fixed-wing_aircraft), though a wide range of different types of jet aircraft exists– both for civilian and military purposes. Most jet aircraft need to fly at high speeds– either [supersonic](/source/supersonic), or just below the speed of sound ([transonic](/source/transonic)) in order to achieve efficient flight. They typically cruise around [Mach](/source/Mach_number) 0.8 (981 km/h (610 mph)), and at altitudes around 10,000-15,000 m (33,000-49,000 ft) or higher, where jet engines operate most efficiently. This contrasts with [propeller-driven aircraft](/source/Propeller_(aircraft)), which achieve peak efficiency at much lower speeds and altitudes. Jet aircraft are usually designed using the [Whitcomb area rule](/source/Whitcomb_area_rule), which states that the total area of the cross-section of an aircraft must be approximately the same as that of a [Sears-Haack body](/source/Sears-Haack_body). The application of this rule minimizes the production of shockwaves, which waste energy. [Frank Whittle](/source/Frank_Whittle), an [English](/source/English_people) inventor and [RAF](/source/RAF) officer, began development of a viable jet engine in 1928,{{cite web |date=10 November 2008 |title=Sir Frank Whittle - Jet Engine Inventor - Born In Coventry |url=http://www.cwn.org.uk/heritage/people/whittle/biography.html |url-status=live |archive-url=https://web.archive.org/web/20171020155022/http://www.cwn.org.uk/heritage/people/whittle/biography.html |archive-date=20 October 2017 |access-date=6 May 2018 |website=CWN}} while [Hans von Ohain](/source/Hans_von_Ohain) in Germany began to independently work on similar concepts in the early 1930s. Thus, in August of 1939, the world's first jet aircraft, the [Heinkel He 178](/source/Heinkel_He_178), took its maiden flight. ==History== [[File:Ohain USAF He 178 page61.jpg|thumb|left|The [Heinkel He 178](/source/Heinkel_He_178) was the first aircraft to fly on turbojet power, in August 1939]] After the first powered aircraft took flight, a multitude of jet designs and approaches were suggested. For example, [René Lorin](/source/Ren%C3%A9_Lorin), O. Morise, and H. S. Harris all proposed different systems for creating a jet efflux.{{cite journal |url=http://www.flightglobal.com/pdfarchive/view/1941/1941%20-%202221.html |title=Jet Propulsion of Aircraft Part III |url-status=dead |archive-url=https://web.archive.org/web/20121105190203/http://www.flightglobal.com/pdfarchive/view/1941/1941%20-%202221.html |archive-date=2012-11-05 |author=G Geoffrey Smith |magazine=Flight |date=September 25, 1941}} Additionally, during the 1920s and 1930s, a variety of [motorjet](/source/motorjet), [turboprop](/source/turboprop), [pulsejet](/source/pulsejet) and [rocket powered](/source/rocket-powered_aircraft) aircraft were designed. Rocket engine research had been underway in Germany, and in 1928 the [Lippisch Ente](/source/Lippisch_Ente), which had previously been flown as a glider, became the first aircraft to fly using rocket power.[http://www.daviddarling.info/encyclopedia/L/Lippisch_Ente.htm "Lippisch Ente."] {{Webarchive|url=https://web.archive.org/web/20200413203215/http://www.daviddarling.info/encyclopedia/L/Lippisch_Ente.htm |date=2020-04-13 }} ''The Internet Encyclopedia of Science: Experimental Aircraft.'' Retrieved: 26 September 2011. The next year, in 1929, the [Opel RAK.1](/source/Opel_RAK.1) became the first purpose-built rocket aircraft to fly. The [turbojet](/source/turbojet) was independently developed in the 1930s by [Frank Whittle](/source/Frank_Whittle) and, later, [Hans von Ohain](/source/Hans_von_Ohain). The first turbojet aircraft to fly was the [Heinkel He 178](/source/Heinkel_He_178), on August 27, 1939 in [Rostock](/source/Rostock) (Germany), powered by von Ohain's design.Warsitz, Lutz: [http://www.pen-and-sword.co.uk/?product_id=1762 ''The First Jet Pilot – The Story of German Test Pilot Erich Warsitz'' (p. 125), Pen and Sword Books Ltd., England, 2009] {{webarchive|url=https://web.archive.org/web/20100603014802/http://www.pen-and-sword.co.uk/?product_id=1762 |date=2010-06-03}} However, "[creep](/source/Gas_turbine)" (metal fatigue caused by the high temperatures within the engine) caused the engine to burn out quickly. Von Ohain's design, an axial-flow engine, as opposed to Whittle's centrifugal flow engine, was eventually adopted by most manufacturers by the 1950s.Experimental & Prototype US Air Force Jet Fighters, Jenkins & Landis, 2008{{cite news | url=https://www.nytimes.com/1996/08/10/world/frank-whittle-89-dies-his-jet-engine-propelled-progress.html | title=Frank Whittle, 89, Dies; His Jet Engine Propelled Progress | work=The New York Times | date=10 August 1996 | last1=Foderaro | first1=Lisa W. }} The first jet-propelled aircraft to gain public attention was the [Italian](/source/Kingdom_of_Italy) [Caproni Campini N.1](/source/Caproni_Campini_N.1) [motorjet](/source/motorjet) prototype, which flew on August 27, 1940.{{cite web|url=http://www.flightglobal.com/pdfarchive/view/1941/1941%20-%201950.html|title=''Flight'' 28 August 1941|website=flightglobal.com |access-date=6 May 2018|url-status=live |archive-url=https://web.archive.org/web/20171020161845/https://www.flightglobal.com/pdfarchive/view/1941/1941%20-%201950.html|archive-date=20 October 2017}} Secondo Campini began development of the motorjet in 1932. This design differed from a true turbojet in that the turbine was driven by a piston engine, rather than combustion of the turbine gases. The British experimental [Gloster E.28/39](/source/Gloster_E.28%2F39) took its first flight on May 15, 1941, powered by [Sir Frank Whittle](/source/Sir_Frank_Whittle)'s turbojet,[http://www.flightglobal.com/pdfarchive/view/1949/1949%20-%201789.html? "No Airscrew Necessary..."] {{webarchive|url=https://web.archive.org/web/20121025175115/http://www.flightglobal.com/pdfarchive/view/1949/1949%20-%201789.html |date=2012-10-25 }} ''Flight''(flightglobal.com), 27 October 1949 p554 and the United States [Bell XP-59A](/source/Bell_P-59_Airacomet) flew on October 1, 1942, using of a version of the Whittle engine built by [General Electric](/source/General_Electric). The [Gloster Meteor](/source/Gloster_Meteor) was the first production jet. The prototype for this jet was first flown on March 5, 1943, and the first produced aircraft on January 12, 1944.Butler, 2006, p.8Butler, 2006, p.23 == Types of jet aircraft == === Military jet aircraft === The [Messerschmitt Me 262](/source/Messerschmitt_Me_262) (Me 262) was the first operational [jet fighter](/source/fighter_aircraft),Hecht, Heinrich. ''The World's First Turbojet Fighter – Messerschmitt Me 262''. Atglen, Pennsylvania: Schiffer Publishing, 1990. {{ISBN|0-88740-234-8}}.{{Page needed|date=October 2010}} entering service on April 19, 1944. Up to 1,400 Me 262 were produced, with 300 going into combat. One Me 262 scored the first combat victory for jet fighters on July 26, 1944, but the Me 262 squadrons became operational too late to have significant effects on the outcome of [World War II](/source/World_War_II). Around this time, mid 1944, the United Kingdom's Meteor was being used for defense of the UK against the [V-1 flying bomb](/source/V-1_flying_bomb)– the V-1 itself being a [pulsejet](/source/pulsejet)-powered aircraft and direct ancestor of the [cruise missile](/source/cruise_missile). This same year, Germany introduced the [Arado Ar 234](/source/Arado_Ar_234) jet reconnaissance and bomber aircraft into service (though primarily used in the former role), along with the [Heinkel He 162](/source/Heinkel_He_162) ''Spatz'' single-jet [light fighter](/source/light_fighter) appearing later in the year. USSR tested its own [Bereznyak-Isayev BI-1](/source/Bereznyak-Isayev_BI-1) in 1942, but the project was scrapped by leader [Joseph Stalin](/source/Joseph_Stalin) in 1945. The [Imperial Japanese Navy](/source/Imperial_Japanese_Navy) also developed jet aircraft in 1945, including the [Nakajima J9Y Kikka](/source/Nakajima_Kikka), a modified, and slightly smaller version of the Me 262 that had folding wings. By the end of 1945, the US had introduced their first jet fighter, the [Lockheed P-80 Shooting Star](/source/Lockheed_P-80_Shooting_Star), into service and the UK its second fighter design, the [de Havilland Vampire](/source/de_Havilland_Vampire). The US introduced the [North American B-45 Tornado](/source/North_American_B-45_Tornado), their first jet bomber, into service in 1948. It was capable of carrying nuclear weapons, but was used for reconnaissance over Korea. On November 8, 1950, during the [Korean War](/source/Korean_War), [United States Air Force](/source/United_States_Air_Force) Lt. Russell J. Brown, flying in a [Lockheed F-80 Shooting Star](/source/P-80_Shooting_Star), intercepted two [North Korea](/source/North_Korea)n [MiG-15](/source/MiG-15)s near the [Yalu River](/source/Yalu_River) and shot them down in the first jet-to-jet [dogfight](/source/dogfight) in history. The UK put the [English Electric Canberra](/source/English_Electric_Canberra) into service in 1951 as a [light bomber](/source/light_bomber). It was designed to fly higher and faster than any [interceptor](/source/Interceptor_aircraft). The fastest military jet aircraft was the [SR-71 Blackbird](/source/SR-71_Blackbird) at Mach 3.35 ({{cvt|3661|km/h}}). === Commercial jet aircraft === thumb|The Boeing 707 popularised commercial jet travel [[File:McDonnell Douglas DC-10-30, Omni Air International - OAI AN0377799.jpg|thumb|An [Omni](/source/Omni_Air_International), [McDonnell Douglas DC-10](/source/McDonnell_Douglas_DC-10) in July 2003, an example of a [trijet](/source/trijet) configuration]] [[File:British Airways Concorde G-BOAC 03.jpg|thumb|left|The [Concorde](/source/Concorde) was the longest running commercial [SST](/source/Supersonic_transport) providing service from 1976 to 2003]] The first commercial jet service was operated in 1952 by [BOAC](/source/BOAC). This service flew from [London](/source/London) to [Johannesburg](/source/Johannesburg), using the [de Havilland Comet](/source/de_Havilland_Comet) [jetliner](/source/jet_airliner). The Comet travelled faster and higher than propeller aircraft, and provided a quieter and smoother ride for passengers. However, due to a design defect, and use of aluminum alloys, the aircraft suffered catastrophic [metal fatigue](/source/metal_fatigue), leading to several crashes.{{cite web | title=Jet! When Britain Ruled the Skies | website=BBC| url=https://www.bbc.co.uk/programmes/b01m85vv | access-date=17 February 2023}} Due to these accidents, the [Boeing 707](/source/Boeing_707) gained the opportunity to enter service in 1958 and dominate the market for civilian airliners. The 707's underslung engines were found to be advantageous in the event of a propellant leak, making its visual appearance contrast that of the Comet, which had blended wings containing hidden engines. The 707's overall shape is similar to that of contemporary aircraft, with marked commonality still evident today. Some examples of this include the [Boeing 737](/source/Boeing_737) (fuselage) and [Airbus A340](/source/Airbus_A340) (single deck, [swept wing](/source/swept_wing), four below-wing engines). [Turbofan](/source/Turbofan) aircraft, which had greater [fuel efficiency](/source/fuel_efficiency), began entering service in the 1950s and 1960s, and eventually became the most commonly used type of jet. The [Tu-144](/source/Tu-144) [supersonic transport](/source/supersonic_transport) was the fastest commercial jet aircraft at Mach 2.35 ({{cvt|2503|km/h}}). It went into service in 1975, but was withdrawn from commercial service shortly afterwards. The Mach 2 [Concorde](/source/Concorde) entered service in 1976 and flew for 27 years. === Other === Though the term 'jet aircraft' is commonly used to denote gas turbine based [airbreathing jet engine](/source/airbreathing_jet_engine)s, rockets and scramjets are both also propelled by jet propulsion. [[File:XH-59 U.S. Army demonstrator.jpg|thumb|The Sikorsky S-69 was a [compound helicopter](/source/compound_helicopter) with auxiliary turbojets]] [Cruise missile](/source/Cruise_missile)s are single-use unmanned jet aircraft, powered predominantly by ramjets, turbojets, or turbofans, but they will often have a rocket propulsion system for initial propulsion. The fastest airbreathing jet aircraft is the unmanned [X-43](/source/NASA_X-43) scramjet at around Mach 9–10. The fastest manned (rocket) aircraft is the [X-15](/source/X-15) at Mach 6.85. The [Space Shuttle](/source/Space_Shuttle), while faster than the X-43 or X-15, was not regarded as an aircraft during ascent since it was carried [ballistically](/source/ballistics) by rocket thrust, rather than the air. Upon re-entry to Earth, it was classified (like a glider) as an unpowered aircraft. The first flight took place in 1981. The [Bell 533](/source/Bell_533) (1964), [Lockheed XH-51](/source/Lockheed_XH-51) (1965), and [Sikorsky S-69](/source/Sikorsky_S-69) (1977-1981) are examples of [compound helicopter](/source/compound_helicopter) designs where jet exhaust added to forward thrust.{{cite web|url= https://spectrum.ieee.org/the-fastest-helicopter-on-earth |title=The Fastest Helicopter on Earth |author1=Thomas Lawrence |author2=David Jenney |publisher=[IEEE Spectrum](/source/IEEE_Spectrum) |date=31 Aug 2010|access-date=1 August 2017 |archive-url= https://web.archive.org/web/20170130223834/https://spectrum.ieee.org/aerospace/aviation/the-fastest-helicopter-on-earth |archive-date=30 January 2017 |url-status=live}} The [Hiller YH-32 Hornet](/source/Hiller_YH-32_Hornet) and [Fairey Ultra-light Helicopter](/source/Fairey_Ultra-light_Helicopter) were among many helicopters where the rotors were driven by [tip jet](/source/tip_jet)s. Jet-powered [wingsuits](/source/Wingsuit_flying) exist – powered by model aircraft jet engines – but can only fly short durations, and need to be launched at height.{{cite web|url=https://www.wired.com/2013/07/how-to-fly-like-jetman/|title='Jetman' Yves Rossy Shows Us How to Fly His Carbon Fiber Jet Wing|publisher=[Wired](/source/Wired_(magazine)) |date=31 July 2013 |access-date=1 August 2017 |archive-url= https://web.archive.org/web/20170102151845/https://www.wired.com/2013/07/how-to-fly-like-jetman/ |archive-date=2 January 2017 |url-status= live }} ==Jet engines== {{Main|Jet engine}} Several types of engines operate by expelling hot gas: [[File:Lockheed SR-71 Blackbird (modified).jpg|thumb|The [Lockheed SR-71](/source/Lockheed_SR-71_Blackbird) was one of the fastest jets, flying at Mach 3.35 ({{cvt|3661|km/h}}]] *[turbojet](/source/turbojet) *[turbofan](/source/turbofan) *[ramjet](/source/ramjet) *[turboprop](/source/turboprop) Each different kind of engine achieves a different purpose. Turbojets have a high exhaust speed, and low frontal cross-section, making them best suited to supersonic flight. Although once widely used, they are relatively inefficient compared to [turboprop](/source/turboprop) and turbofans for subsonic flight. The last major aircraft to use turbojets were the Concorde and the Tu-144 [supersonic transport](/source/supersonic_transport)s. Low bypass turbofans have a lower exhaust speed than turbojets, and are mostly used for high sonic, transonic, and low supersonic speeds. High bypass turbofans are relatively efficient, and are used by subsonic aircraft, such as airliners. ==Propulsive efficiency== {{main|Propulsive efficiency}} In aircraft ''overall propulsive efficiency'' \eta is the efficiency, in percent, with which the energy contained in a vehicle's propellant is converted into useful energy, to replace losses due to [air drag](/source/air_drag), gravity, and acceleration. It can also be stated as the proportion of the mechanical energy actually used to propel the aircraft. It is always less than 100% because of kinetic energy loss to the exhaust, and less-than-ideal efficiency of the propulsive mechanism, whether a [propeller](/source/Propeller_(aircraft)), a jet exhaust, or a fan. In addition, propulsive efficiency is greatly dependent on [air density](/source/air_density) and airspeed. Mathematically, it is represented as \eta = \eta_c \eta_p[http://www.hq.nasa.gov/pao/History/SP-468/ch10-3.htm ch10-3] {{webarchive|url=https://web.archive.org/web/20100914184628/http://www.hq.nasa.gov/pao/History/SP-468/ch10-3.htm |date=2010-09-14 }} where \eta_c is the [cycle efficiency](/source/cycle_efficiency) and \eta_p is the propulsive efficiency. The cycle efficiency, in percent, is the proportion of energy that can be derived from the energy source that is converted to mechanical energy by the [engine](/source/engine). thumb|right|Dependence of the propulsive efficiency (\eta_p) upon the vehicle speed/exhaust speed ratio (v/c) for rocket and jet engines For jet aircraft the ''propulsive efficiency'' (essentially [energy efficiency](/source/Energy_conservation)) is highest when the engine emits an exhaust jet at a speed that is the same as, or nearly the same as, the vehicle velocity. The exact formula for air-breathing engines as given in the literature,K.Honicke, R.Lindner, P.Anders, M.Krahl, H.Hadrich, K.Rohricht. Beschreibung der Konstruktion der Triebwerksanlagen. Interflug, Berlin, 1968Spittle, Peter. [http://users.encs.concordia.ca/~kadem/Rolls%20Royce.pdf "Gas turbine technology"] {{webarchive|url=https://web.archive.org/web/20141031143409/http://users.encs.concordia.ca/~kadem/Rolls%20Royce.pdf |date=2014-10-31 }} p507, ''[Rolls-Royce plc](/source/Rolls-Royce_plc)'', 2003. Retrieved: 21 July 2012. is :\eta_p = \frac{2}{1 + \frac{c}{v}} where ''c'' is the exhaust speed, and ''v'' is the speed of the aircraft. ==Range== {{main|Range (aircraft)}} For a long range jet operating in the [stratosphere](/source/stratosphere), the speed of sound is constant, hence flying at fixed [angle of attack](/source/angle_of_attack) and constant [Mach number](/source/Mach_number) causes the aircraft to climb, without changing the value of the local speed of sound. In this case: V=aM where M is the cruise Mach number and a the local speed of sound. The range equation can be shown to be: R=\frac{aM}{c_T}\frac{C_L}{C_D}ln\frac{W_1}{W_2} which is known as the ''Breguet range equation'' after the French aviation pioneer [Louis Charles Breguet](/source/Louis_Charles_Breguet). ==See also== * {{annotated link|Coanda-1910}} * {{annotated link|Commercial aviation}} * {{annotated link|Contrail}} * {{annotated link|Jet airliner}} * {{annotated link|Jet noise}} * {{annotated link|Wide-body aircraft|Jumbo jet}} * {{annotated link|Very light jet}} * {{annotated link|List of jet aircraft of World War II}} ==References== ===Citations=== {{Reflist}} ===Bibliography=== *{{cite book|last1=Butler|first1=Phil|last2=Buttler|first2=Tony|title=Gloster Meteor: Britain's Celebrated First-Generation Jet |publisher=Midland Publishing|location=Surrey, UK|year=2006|isbn=1-85780-230-6|page=23}} * Lutz Warsitz: ''The First Jet Pilot – The Story of German Test Pilot Erich Warsitz'', Pen and Sword Books Ltd., England, 2009, {{ISBN|978-1-84415-818-8}}, [http://www.pen-and-sword.co.uk/?product_id=1762 English Edition] *{{Cite book |last1=Radinger |first1=Will |last2=Schick |first2=Walter Schick |year=1996 |title=Me 262 |language=de |location=Berlin |publisher=Avantic Verlag GmbH |isbn=978-3-925505-21-8}} ==External links== {{Commons category|Aircraft with jet engines}} * [http://www.erichwarsitz.com The official Erich Warsitz website (the world's first jet pilot), inclusive rare videos (Heinkel He 178) and audio commentaries] {{Authority control}} {{DEFAULTSORT:Jet Aircraft}} Category:Jet aircraft --- Adapted from the Wikipedia article [Jet aircraft](https://en.wikipedia.org/wiki/Jet_aircraft) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Jet_aircraft?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.