# List of experimental aircraft

As used here, an experimental or research and development aircraft, sometimes also called an X-plane, is one which is designed or substantially adapted to investigate novel flight technologies.

## Argentina

* FMA I.Ae. 37 glider – testbed for production fighter

## Australia

* GAF Pika – manned test craft for drone program

## Brazil

* Baumgartl PB-60 – towed experimental rotor kite

## Canada

* AEA Silver Dart (1909) – First aircraft to fly in Canada
* Avro Canada Avrocar – Ducted fan VTOL
* Birdman Project 102 –
* Canadair CL-52 – jet engine testbed (converted Boeing B-47)
* Canadair CL-84 Dynavert – tilt-wing VTOL
* de Havilland Canada C-8A – Quiet Short-Haul Research Aircraft
* de Havilland Canada C-8A – Air-Cushion Landing System
* de Havilland Canada C-8A – Augmentor Wing
* Marsden Gemini – variable-geometry glider
* NRC tailless glider – tailless flying wing
* UTIAS Ornithopter No.1

## France

* Aérocentre NC.130 1939 – High-altitude flight
* Aérospatiale Ludion 1967 – Thrust vectored rocket VTOL
* Arsenal-Delanne 10 – Tandem wing
* Arsenal VG 70 – High speed research
* Arsenal O.101 – Aerodynamic research
* Arsenal 2301/SFECMAS 2301 and SFECMAS 1301 – Supersonic research glider
* Breguet-Dorand Gyroplane Laboratoire – Experimental helicopter
* Breguet-Richet Gyroplane – Experimental helicopter
* Breguet Laboratoire Eiffel [fr] – Monoplane testbed
* Dassault Balzac V – VTOL testbed
* Dassault Mirage IIIV – VTOL testbed
* Dassault Milan – Canard research
* Dassault Mirage G – Variable geometry
* Dassault LOGIDUC – Unmanned combat aerial vehicle UCAV development
* Dassault nEUROn – UCAV technology demonstrator
* Farman F.1010 – Heavy cannon flight testing
* Farman F.1020 – Semi-circular wing
* Fouga Gemeaux – Engine testbed
* Gastambide-Levavasseur Variable Surface Aircraft – Variable chord wing testbed
* Gérin Varivol – Variable chord wing testbed
* Hanriot HD.28 – tested a Vee tail
* Hurel-Dubois HD.10 – Very high aspect ratio wings
* Leduc 0.10 – Ramjet
* Leduc 0.21 – Ramjet
* Makhonine Mak-10 – Variable span wing
* Messier Monoplace Laboratorie – Retractable bicycle undercarriage testbed.
* Nord 500 – VTOL tilt ducted fan research aircraft
* Nord 1402/1405 Gerfaut – Delta wing research aircraft
* Nord 1500 Griffon – Ramjet
* Nord 1601 – Swept wing research aircraft
* Payen PA-22 – Tandem delta/normal wings
* Payen Pa 49 – Tandem delta/normal wings
* Potez-CAMS 160 – 5/13th scale six engine aerodynamic testbed for development of CAMS 161
* Robin X4 – Materials and configuration testbed
* SNECMA Atar Volant – Vertical lift jet
* SNECMA Coléoptère – Vertical lift annular wing
* Sud Est SE-1210 scale aerodynamic testbed for SE-1200 transatlantic flying boat
* Sud-Ouest Ariel – Tip-jet rotor helicopter
* Sud-Ouest Farfadet – Convertiplane
* Sud-Ouest Triton – First French jet aircraft

## Germany

* Akaflieg Berlin B 9 1943. – Prone pilot
* Albatros L.81 – Elektron metal structure testbed
* AVA AF 1 – Augumented lift
* DFS 194 1940 – Tailless rocket aircraft used in development of Me 163
* DFS 346 1948 – Supersonic reconnaissance aircraft used for research
* Dassault/Dornier Alpha Jet TransSonische Tragflügel (TST) – Transonic supercritical wing research
* Dornier Do 29 – Tilt rotor STOL
* Dornier Do 31 – Experimental VTOL transport
* EWR VJ 101 – Experimental tiltjet VTOL fighter
* Fieseler Fi 158 – Testbed for radio control system
* Flettner airplane – Magnus effect test vehicle
* Flettner Fl 185 – Gyrodyne
* Focke-Wulf F 19 – Multi-engined canard demonstrator
* Fokker V.1 – Structures and aerodynamics testbed
* Göppingen Gö 8 – Development aircraft for Do 214
* Göppingen Gö 9 – Pusher (behind tail) aerodynamic testbed for Dornier Do 335 development
* Gotha Go 147 – Tailless research aircraft
* Heinkel He 119 – High-performance research aircraft
* Heinkel He 176 – Rocket research aircraft
* Heinkel He 178 – Jet engine research aircraft
* Horten H.III – Flying wing
* Horten H.IV – Flying wing
* Horten Ho VI – Flying wing
* Junkers J 1 – Pioneering all-metal cantilever monoplane (1915)
* Junkers EF 61 – Pressurization
* Junkers Ju 49 – High-altitude test aircraft
* Lippisch Delta IV – Delta wing
* Lippisch DM-1 1944 – Delta wing glider
* Lippisch Ente – Rocket-powered canard technology demonstrator
* Lippisch P.13a – Coal-powered delta wing
* Messerschmitt Me P.1101 – Variable geometry (swing-wing) jet
* Opel RAK.1 – Rocket propulsion technology demonstrator
* RFB X-113 – Wing in ground effect vehicle
* RFB X-114 – Wing in ground effect vehicle
* Sack AS-6 – Disk wing technology demonstrator
* Schmeidler SN.2 – Wing flaps
* VFW VAK 191B – VTOL fighter
* Zeppelin-Lindau V I – All-metal stressed skin construction

## Italy

* Ambrosini Sagittario 1953 – Swept wing research aircraft
* Bossi-Bonomi Pedaliante 1936 – Human-powered aircraft
* Caproni Campini N.1 1940 – Jet engine research
* Jona J-6 – Tilting wing stabilisation system
* Lualdi-Tassotti ES 53 – Gyro stabilized helicopter
* Piaggio P.111 – High-altitude research
* S.C.A. SS.2 – Experimental canard
* S.C.A. SS.3 Anitra – Experimental canard
* Stipa-Caproni – Ducted prop research
* Sandro Simoncini - Experimental helicopter

## Poland

* Flugtechnische Fertigungsgemeinschaft Prag FGP 227 – Scale proof of concept for German BV 238
* Lala-1 – Jet biplane testbed for PZL M-15 Belphegor

## Japan

* NAL AsukaGasuden Koken 1937 – Long range experimental aircraft
* Honda MH02 1993 – Over wing engines, forward swept wing
* Kawasaki Ki-78 1942 – High speed research aircraft
* Kayaba Ku-2 1940 – Tailless glider
* Kayaba Ku-3 – Tailless glider
* Kayaba Ku-4 – Tailless research aircraft
* Kimura HK-1 – Tailless glider
* Mitsubishi RP-1 – Experimental helicopter
* MXY-6 – Canard scale testbed for Kyushu J7W
* X1G – High-lift device based on Saab 91 Safir
* National Aerospace Laboratory (NAL) Asuka – STOL
* Shin Meiwa UF-XS – Proof of concept demonstrator for Shin Meiwa US-1A
* Mitsubishi T-2CCV - Experimental aircraft for CCV technology
* Mitsubishi X-2 Shinshin – Advanced stealth technology demonstrator

## Russia/Soviet Union

* Alexeyev – Ekranoplans
* Antonov A-40 1942 – Tank glider
* Antonov 181 – Blown channel wing demonstrator
* Bartini Beriev VVA-14 1972 – Ekranoplan ground effect vehicle
* Bartini Stal-6 – High speed aircraft
* Chyeranovskii BICh-3 – Tailless delta research aircraft
* Chyeranovskii BICh-11 – Flying wing to test wingtip rudders
* Chyeranovskii BICh-16 – Human-powered ornithopter
* Chyeranovskii BICh-18 – Human-powered ornithopter
* Chizhevski BOK-1 – High-altitude research aircraft
* Chizhevski BOK-5 – Tailless research aircraft
* Grigorovich I-Z – Recoilless cannon evaluation
* Grushin Octyabrenok – Tandem wing
* Ilyushin Il-76LL – Engine testbeds (5)
* Kozlov PS – Visibility (covered in transparent material)
* MAI EMAI – Magnesium construction
* Mikoyan-Gurevich MiG-8 Utka – Pusher canard proof of concept (1945)
* Mikoyan-Gurevich MiG-105 – Lifting body
* Mikoyan Project 1.44 – Technology demonstrator
* Mikoyan-Gurevich N – Mixed propulsion system
* Moskalyev SAM-9 Strela – Delta wing
* NIAI RK – Telescopic wings
* NIAI RK-I – Telescopic wings
* Nikitin PSN-2 – Glider bombers
* Sukhanov Diskoplan – Disk wings
* Sukhoi T-10 – Technology demonstrator
* Sukhoi T-58VD – VTOL research aircraft
* Sukhoi Su-47 – Technology demonstrator
* Thermoplan – Heavy lift lenticular-shaped hybrid airship technology demonstrator
* Tsybin LL – Forward swept wing
* Tsybin NM-1 – Proof of concept
* Tupolev Tu-95LAL – Nuclear-powered aircraft
* Ushakov – Flying submarines
* Yakovlev Yak-36 – VTOL technology demonstrator
* Yakovlev Yak-42LL – Progress D-236 propfan engine testbed
* Yakovlev Yak-1000 – Supersonic technology demonstrator
* Zveno project – Parasite fighters

## Spain

* Cierva C.4 1923 – Experimental autogyro, first to fly
* Cierva C.6 1924 – Experimental autogyro

## Sweden

* Saab 201 - Aerodynamic testbed for Saab 29 Tunnan
* Saab 202 – Aerodynamic testbed for Saab 32 Lansen
* Saab 210 1952 – Aerodynamic testbed for double delta concept for Saab 35 Draken

## Switzerland

* Solar Impulse Project – Solar power technology demonstrator

## United Kingdom

* Armstrong Whitworth Ape 1926 – Variable configuration aerodynamic test vehicle
* Armstrong Whitworth A.W.52 1947 – Jet powered flying wing
* Avro 707 1949 – Aerodynamic proof of concept for Avro Vulcan delta wing bomber
* Avro Ashton – Jet engine research vehicle based on Avro Tudor
* BAC 221 – High speed delta wing research
* Baynes Bat – Experimental tailless glider
* Blackburn B-20 – Retractable hull seaplane
* Boulton Paul P.6 – Wing research
* Boulton Paul P.92 – Half-scale proof of concept for turret fighter
* Boulton Paul P.111 – Delta-wing research aircraft
* Boulton Paul P.120 – Delta-wing research aircraft
* Bristol 138 – High-altitude research aircraft
* Bristol 188 – High speed flight research
* British Aerospace EAP – Technology demonstrator
* Cierva W.9 – Experimental helicopter with anti-torque jet efflux
* de Havilland DH 108 Swallow – Swept wing tailless transsonic research aircraft
* English Electric P.1A – Supersonic research aircraft
* modified Fairey Battle – Engine testbed for Rolls-Royce Exe, Fairey Prince (H-16) and Napier Dagger.
* Fairey Delta 1 – Delta-wing research aircraft
* Fairey Delta 2 – Delta-wing research aircraft
* Fairey Jet Gyrodyne – Jet-powered rotor technology demonstrator
* Folland Fo.108 – Engine test bed
* General Aircraft GAL.56 – Tailless swept wing glider
* Gloster E.28/39 – Jet engine research
* Gloster Meteor F8 "Prone Pilot" – Prone position flight control research
* Gloster Trent Meteor – Turboprop propulsion
* Hafner A.R.III Gyroplane – Experimental autogyro
* Handley Page H.P.17 – Aerodynamic slot research
* Handley Page H.P.20 – Aerodynamic slot research
* Handley Page H.P.75 Manx – Tailless flight research
* Handley Page HP.88 – Handley Page Victor aerodynamic testbed
* Handley Page HP.115 – Low speed delta-wing research
* Hawker P.1052 – Swept wing testbed
* Hawker P.1072 – Armstrong Siddeley Snarler rocket booster testbed
* Hawker P.1127 – V/STOL technology demonstrator, led to Hawker Harrier
* Hillson Bi-mono – Slip-wing research
* Hunting H.126 – Blown flap research
* Miles M.3E Gillette Falcon – High speed flight research
* Miles M.30 – Blended wing body design
* Miles M.35 Libellula – Tandem-wing fighter testbed
* Miles M.39B Libellula – Tandem-wing research
* Miles M.52 – Supersonic flight research
* Parnall Parasol – Wing pressure and aileron testing
* Parnall Peto – Experimental submarine-launched aircraft
* Parnall Prawn – Flying boat testing buried engine with variable-angle thrust line
* Reid and Sigrist R.S.4 Bobsleigh – Prone-pilot research
* Rolls-Royce Thrust Measuring Rig – Low speed VTOL control test rig
* Saro Shrimp – Experimental half-scale flying boat for development of cancelled Saunders-Roe S.38
* Saunders-Roe SR.53 – Mixed rocket/jet propulsion development aircraft for cancelled Saunders-Roe SR.177
* Short Cockle – Metal construction technology demonstrator for flying boats
* Short Mussel – Testing metal construction techniques for aircraft floats
* Short S.6 Sturgeon – Tested aluminium construction techniques for aircraft
* Short S.31 – Half-scale model for Short Stirling development
* Short SB.1 – Tailless glider for isoclinic wing research
* Short SB.4 Sherpa – Powered isoclinic wing research
* Short SB.5 – English Electric Lightning wing research
* Short SC.1 – VTOL research
* Short Silver Streak – Stressed skin construction, developed into Short Springbok
* Supermarine 508 – Development aircraft with vee tail
* Supermarine 525 – Swept wing development aircraft for Supermarine Scimitar program
* Vickers Type 618 Nene-Viking – Jet engine testbed
* Vickers Type 470 and Type 486 Wellington – Whittle jet engine testbeds
* Vickers Type 602 Wellington Mark X – Rolls-Royce Dart turboprop testbed
* Westland-Hill Pterodactyl – Tailless monoplane testbeds
* Youngman-Baynes High Lift – Youngman flap testbed

## United States
### X-planes

* Bell X-1 – Supersonic flight and sound barrier
* Bell X-2 – Mach 2–3 supersonic flight
* Douglas X-3 Stiletto – Sustained supersonic flight
* Northrop X-4 Bantam – Tailless aircraft
* Bell X-5 – Variable-sweep wing
* Convair X-6 – Nuclear reactor test aircraft (for nuclear-powered aircraft)
* Lockheed X-7 – Unmanned ramjet and guidance test missile
* Aerojet General X-8 – Sounding rocket (became Aerobee)
* Bell X-9 Shrike – Guided missile
* North American X-10 – Unmanned missile technology demonstrator
* Convair X-11 – Single engine missile testbed for Atlas
* Convair X-12 – Three engine missile testbed for Atlas
* Ryan X-13 Vertijet – Tail sitter VTOL jet
* Bell X-14 – Thrust vectoring VTOL jet
* North American X-15 – Hypersonic rocket-powered research aircraft (Mach 6)
* Bell X-16 - High-altitude reconnaissance jet
* Lockheed X-17 – Research rocket testing high mach re-entry
* Hiller X-18 – Tiltwing STOVL cargo aircraft
* Curtiss-Wright X-19 – VTOL tiltrotor
* Boeing X-20 Dyna-Soar – Spaceplane program
* Northrop X-21 – Laminar flow wing
* Bell X-22 – Ducted fan V/STOL
* Martin X-23 PRIME – Lifting body reentry vehicle testbed
* Martin Marietta X-24 – Lifting body test aircraft
* Bensen X-25 – Single-seat autogyro
* Schweizer X-26 Frigate – Sailplane
* Lockheed X-27 Lancer – high-performance technology demonstrator based on Lockheed CL-1200
* Pereira X-28A Sea Skimmer – Single-seat flying boat for US Navy
* Grumman X-29 – Forward-swept wing test aircraft
* Rockwell X-30 – Single-stage-to-orbit spacecraft
* Rockwell-MBB X-31 – Extreme angle of attack test aircraft
* Boeing X-32 – Joint Strike Fighter Program technology demonstrator
* Lockheed Martin X-33 – Unmanned scale demonstrator for VentureStar single stage to orbit spacecraft
* Orbital Sciences X-34 – Reusable launch vehicle testbed
* Lockheed Martin X-35 – Joint Strike Fighter Program technology demonstrator, developed into F-35 Lightning II
* McDonnell Douglas X-36 – Tailless fighter research agility aircraft
* Boeing X-37 – Reusable unmanned spacecraft
* NASA X-38 – Crew return vehicle for International Space Station (cancelled after tests)
* X-39 – Reserved for USAF/DARPA program use
* Boeing X-40 Space Maneuver Vehicle – Testbed for X-37 guidance and flight characteristics
* X-41 Common Aero Vehicle – Classified DARPA/NASA maneuvering re-entry vehicle
* X-42 Pop-Up Upper Stage – Classified rocket upper stage
* NASA X-43 Hyper-X – Hypersonic scramjet
* Lockheed Martin X-44 MANTA – Multi-axis tailless aircraft concept
* Boeing X-45 – Unmanned combat air vehicle
* Boeing X-46 – Unmanned combat air vehicle (proposal only)
* Northrop Grumman X-47A Pegasus – Unmanned combat air vehicle
* Northrop Grumman X-47B Iron Raven – Aircraft carrier capable unmanned combat air vehicle technology demonstrator
* Boeing X-48 – Blended wing aircraft
* Piasecki X-49 – Compound helicopter technology demonstrator
* Boeing X-50 Dragonfly – Gyrodyne unmanned aerial vehicle
* Boeing X-51 Waverider – Mach 5+ scramjet missile demonstrator
* Boeing X-53 Active Aeroelastic Wing – Wing warping flight demonstrator
* Gulfstream X-54 – Supersonic boom intensity research and demonstration aircraft
* Lockheed Martin X-55 – Advanced composites technology demonstrator
* Lockheed Martin X-56 – Flutter suppression and gust load testing unmanned testbed
* NASA X-57 Maxwell - Electric-powered light aircraft
* Lockheed Martin X-59 QueSST - Low-boom supersonic aircraft
* Generation Orbit X-60 - Air-launched single stage suborbital rocket vehicle
* Dynetics X-61 Gremlins - Unmanned aerial vehicle
* General Dynamics X-62 VISTA - Variable stability, thrust vectoring (formerly known as NF-16D VISTA)
* ABL Space Systems X-63 - Aerospike variant of RS1 rocket booster
* Invocon X-64 - Recoverable suborbital rocket
* Aurora X-65 CRANE - active flow control demonstrator
* Boeing X-66 - Truss-Based Wing demonstrator

### Other experimental types

* Acme Sierra 1959 – Technology demonstrator
* AstroFlight Sunrise 1974 – Solar powered drone
* Ball-Bartoe Jetwing 1977 – Blown wing research
* Bell D-292 1985 – Advanced Composite Airframe Program
* Bell L-39 1946 – Swept wing research
* Bell Model 65 1954 – Tiltjet VTOL
* Bell XV-15 1977 – Tiltrotor VTOL, precursor to V-22 Osprey
* Bell 533 1962 – US Army high speed helicopter experiments
* Boeing ecoDemonstrator 2012 – Airliner fuel efficiency and noise reduction technologies
* Budd BB-1 Pioneer 1931 – Stainless steel construction
* Burnelli RB-1 1921 – Lifting body proof of concept vehicle
* Carlson-Lynch Vertipactor 1923 – Wingless VTOL aircraft
* Chrysler VZ-6 1959 – Ducted fan
* Convair NB-36 1955 – Nuclear propelled aircraft testbed
* Convair XFY Pogo 1954 – Fixed propeller VTOL
* Curtiss-Wright VZ-7 1958 – Quadcopter
* Curtiss-Wright X-100 1963 – Tilt rotor VTOL (developed into X-200 and X-19)
* Custer Channel Wings 1953 – Blown half-barrel wings
* Doak VZ-4 1958 – Tilt-fan VTOL
* Douglas D-558-I Skystreak 1947 – Supersonic research
* Douglas D-558-II Skyrocket 1948 – Supersonic research
* Fairchild VZ-5 1959 – Deflected air VTOL
* Farrar LSG-1 Bird Flight Machine 1969 – Glider to research bird flight
* General Dynamics F-16XL 1982 – Relaxed stability delta wing, boundary layer suction laminar flow
* General Dynamics F-16 VISTA 1992 – Variable stability, thrust vectoring (Redesignated X-62 Vista in 2021)
* General Electric GE36 testbed 1986 – Propfan engine testbed on a modified Boeing 727
* Goodyear Inflatoplane 1956 – Inflatable rescue aircraft technology demonstrator
* Gossamer Albatross 1979 – Human-powered flight
* Gossamer Condor 1977 – Human-powered flight
* modified Grumman Gulfstream II – Engine testbed for the NASA Propfan Test Assessment (PTA)
* Hiller VZ-1 Pawnee 1955 – Direct lift rotor platform
* Hypersonic Technology Vehicle 2 2010 – Hypersonic glider
* Kaman K-125 1947 – Intermesh twin rotor helicopter, servo-flap control
* Kaman K-16 – Modified Grumman Goose for tiltwing V/STOL research
* Lockheed Altair 1938 – Twinned engine testbed (both engines were in a single cowl)
* NASA Dryden Lockheed C-140 Jetstar 1964 – Electronic variable stability, propfan engine (1981) and laminar flow wing testbed (1985)
* Lockheed Have Blue – Stealth technology demonstrator
* Lockheed Vega Winnie Mae – high-altitude research – confirmed existence of jet stream
* Lockheed QT-2 – Quiet Thruster noise suppression experiments
* Lockheed XC-35 – Pressurized cabin development
* Lockheed XV-4 Hummingbird – Jetlift VTOL
* LTV XC-142 – VTOL transport technology demonstrator
* Martin 162A Tadpole Clipper – Proof of concept aircraft
* Martin XB-26H Marauder – Tandem undercarriage
* McDonnell Douglas MD-81 UHB – General Electric GE36 and PW-Allison 578-DX propfan engine testbed
* NASA AD-1 – Oblique Wing
* NASA Environmental Research Aircraft and Sensor Technology experimental aircraft – ALTUS, Pathfinder and Helios
* NASA Hyper III – Lifting body remotely piloted vehicle
* NASA M2-F1 – Lifting body/re-entry vehicle
* NASA Pathfinder – Solar-powered aircraft
* Northrop F-5 Shaped Sonic Boom Demonstrator – Shockwave reduction
* Northrop HL-10 – Lifting body/re-entry vehicle research
* Northrop M2-F2 – Lifting body/re-entry vehicle research
* Northrop M2-F3 – Lifting body/re-entry vehicle research
* Northrop N-1M – Flying wing research
* Northrop N-9M – Flying wing proof of concept aircraft for Northrop YB-35
* Northrop Tacit Blue – Stealth technology demonstrator
* Piasecki PV-2 – Helicopter technology demonstrator
* Piasecki VZ-8 Airgeep – Liftfan VTOL research
* Piasecki PA-97 1980 – Heavy lifter
* Republic XF-84H "Thunderscreech" – Supersonic propeller testbed
* Republic XF-91 Thunderceptor – Inversely tapered swept wing
* Rockwell HiMAT – Maneuverability and control research
* Rockwell XFV-12 – Augmented wing vectored thrust VTOL
* Rotary Rocket Roton 1999 – Single stage to orbit helicopter rocket
* Ryan VZ-3 Vertiplane 1958 – Blown flap VTOL research
* Ryan XV-5 Vertifan 1964 – Fan lift VTOL research
* Sawyer Skyjacker II – Low aspect ratio research aircraft
* Scaled Composites Proteus 1998 – Telecommunication relay testbed
* Schweizer SGS 1-29 1958 – Laminar flow research on wings made of metal
* Sikorsky S-69 1981 – Compound co-axial research
* Sikorsky S-72 1976 – Helicopter/aircraft hybrid research
* Sikorsky S-75 1984 – Advanced Composite Aircraft Program
* Sikorsky S-76 SHADOW 1985 – Sikorsky Helicopter Advanced Demonstrator and Operator Workload
* Stinson L-1 Vigilant – One example modified for boundary layer experiments
* Travel Air 2000 – One modified for Besler steam powered aircraft
* Vertol VZ-2 – tilt wing VTOL research
* Vought V-173 – Disk wing research for Vought XF5U
* Vought V-326 – High-altitude test aircraft
* Vought-Sikorsky VS-300 – Helicopter