List of X-planes

Last updated

Bell X-1-2 BellX-1.jpeg
Bell X-1-2

The X-planes are a series of experimental United States aircraft and rockets, used to test and evaluate new technologies and aerodynamic concepts. They have an X designator within the US system of aircraft designations, which denotes the experimental research mission.

Contents

Not all US experimental aircraft have been designated as X-planes; some received US Navy designations before 1962, [1] while others have been known only by manufacturers' designations, [N 1] non-'X'-series designations, [N 2] or classified codenames. [N 3] This list only includes the designated X-planes.

History

The X-planes concept officially came into being in 1944, as a joint programme between the National Advisory Committee for Aeronautics (NACA), the US Navy (USN) and the US Army Air Force (USAAF), in order to pursue research into high-speed aircraft. [2] NACA later became the National Aeronautics and Space Administration (NASA) and the USAAF became the United States Air Force (USAF). Other organizations such as the Defence Advanced Research Projects Agency (DARPA) and the US Marine Corps (USMC) have also since sponsored X-plane projects.

The first experimental aircraft specification, for a transonic rocket plane, was placed in 1945, and the first operational flight of an X-plane took place when the Bell X-1 made its first powered flight nearly three years later at Muroc Air Force Base, California, now known as Edwards Air Force Base. [3] The majority of X-plane testing has since taken place there. [4]

X-planes have since accomplished many aviation "firsts" including breaking speed and altitude barriers, varying wing sweep in flight, implementing exotic alloys and propulsion innovations, and many more. [2]

New X-planes appeared fairly regularly for many years until the flow temporarily stopped in the early 1970s. A series of experimental hypersonic projects, including an advanced version of the Martin Marietta X-24 lifting body, were turned down. Eventually issues with the Rockwell HiMAT advanced UAV led to a crewed X-plane with forward sweep, the Grumman X-29, which flew in 1984. [5]

Some of the X-planes have been well publicized, while others, such as the X-16, have been developed in secrecy. [6] The first, the Bell X-1, became well known in 1947 after it became the first aircraft to break the sound barrier in level flight. [7] Later X-planes supported important research in a multitude of aerodynamic and technical fields, but only the North American X-15 rocket plane of the early 1960s achieved comparable fame to that of the X-1.[ citation needed ] X-planes 8, 9, 11, 12, and 17 were actually missiles [8] used to test new types of engines, and some other vehicles were unoccupied or UAVs (some were remotely flown, some were partially or fully autonomous).

Most X-planes are not expected to go into full-scale production; one exception was the Lockheed Martin X-35, which competed against the Boeing X-32 during the Joint Strike Fighter Program, and has entered production as the F-35 Lightning II. [9]

List

In the list, the date is that of the first flight, or of cancellation if it never flew.

List of X-planes
ImageTypeManufacturerAgencyDateRoleNotes
Bell X-1 46-062 (in flight).jpg X-1 Bell USAF, NACA 1946High-speed and high-altitude flightFirst aircraft to break the sound barrier in level flight. Proved aerodynamic viability of thin wing sections. [10]
Bell X-1A.jpg X-1A X-1B X-1C X-1D BellUSAF, NACA1951High-speed and high-altitude flight
Joe Walker X-1E.jpg X-1E BellUSAF, NACA1955High-speed and high-altitude flight
X-2 After Drop from B-50 Mothership - GPN-2000-000396.jpg X-2 BellUSAF1952High-speed and high-altitude flightFirst aircraft to exceed Mach 3. [11]
Douglas X-3 NASA E-17348.jpg X-3 Stiletto Douglas USAF, NACA1952Highly loaded trapezoidal wing Titanium alloy construction; Underpowered, but provided insights into inertia coupling. [12]
Northrop-X4-Bantam.jpg X-4 Bantam Northrop USAF, NACA1948 Transonic tailless aircraft [13]
Bell-X5-Multiple.jpg X-5 BellUSAF, NACA1951 variable geometry First aircraft to fly with variable wing sweep. [14]
NB-36H producing contrails in flight.jpg X-6 Convair USAF, AEC 1957 Nuclear Propulsion Not built. The Convair NB-36H experiment, a B-36 modified to carry (but not powered by) a nuclear reactor, flew from 1955 to 1957. [15] [16]
X-7 USAF.jpg X-7 Lockheed USAF, USA, USN1951 Ramjet engines. [17]
AerojetX8.jpg X-8 Aerobee Aerojet NACA, USAF, USN1949Upper air research [18] Later models used as sounding rockets.
Bell X-9 trailer.jpg X-9 Shrike BellUSAF1949Guidance and propulsion technologyAssisted development of GAM-63 Rascal missile. [19]
North American X-10 runway.jpg X-10 North American USAF1953 SM-64 Navajo missile testbed. [20]
X-11 ConvairUSAF1953Proposed SM-65 Atlas missile testbed. [21]
X-12 ConvairUSAF1953Proposed SM-65 Atlas missile testbed. [22]
Ryan X-13.jpg X-13 Vertijet Ryan USAF, USN1955 Vertical takeoff and landing (VTOL) tailsitting VTOL flight. [23]
Bell X-14 colour ground.jpg X-14 BellUSAF, NASA1957VTOL Vectored thrust configuration for VTOL flight. [24]
X-15 in flight.jpg X-15 North AmericanUSAF, NASA1959 Hypersonic, high-altitude flightFirst crewed hypersonic aircraft; capable of suborbital spaceflight. [25]
X-15A2 NB-52B 3.jpg X-15A-2 North AmericanUSAF, NASA1964 Hypersonic, high-altitude flightMajor Pete Knight flew the X-15A-2 to a Mach 6.70, making it the fastest piloted flight of the X-plane program.
Bell X-16.jpg X-16 BellUSAF1954High-altitude reconnaissance [26] "X-16" designation used to hide true purpose. [27] Canceled and never flew.
Lockheed X-17 horizontal.jpg X-17 LockheedUSAF, USN1956High Mach number reentry. [28]
Hiller X-18 testplatformLarge.jpg X-18 Hiller USAF, USN1959Vertical and/or short take-off and landing (V/STOL)Evaluated the tiltwing concept for VTOL flight. [29]
Curtiss-Wright X-19 flying.jpg X-19 Curtiss-Wright Tri-service1963 Tandem tiltrotor VTOL [30] XC-143 designation requested but turned down. [31]
NASA Color Dyna Soar.jpg X-20 Dyna-Soar Boeing USAF1963Reusable spaceplane Intended for military missions. [32] Canceled and never built.
X21A.jpg X-21A NorthropUSAF1963 Boundary layer control [33]
X-22a onground bw.jpg X-22 BellTri-service1966Quad ducted fan tiltrotor STOVL [34]
X23 PRIME.JPG X-23 PRIME Martin Marietta USAF1966Maneuvering atmospheric reentry [35] Designation never officially assigned. [31]
X24.jpg X-24A Martin MariettaUSAF, NASA1969Low-speed lifting body [36]
X-24b-flying.jpg X-24B Martin MariettaUSAF, NASA1973Low-speed lifting body [37]
X-25.jpg X-25 Bensen USAF1955Commercial light autogyro for downed pilots. [38]
X-26 sailplane.jpg QT-2PCs in STAAF, RVN Hangar c1968.jpg X-26 Frigate Schweizer DARPA, US Army, USN1967Training glider for yaw-roll coupling Quiet observation aircraft [39]
X-27 mockup.jpg X-27 LockheedNone1971high-performance research aircraft. High-performance fighter [40] Proposed development of Lockheed CL-1200 Lancer. Canceled and never flew.
X-28 on ground.jpg X-28 Sea Skimmer Osprey USN1970Low-cost aerial policing seaplane [41]
Grumman-X29-InFlight.jpg X-29 Grumman DARPA, USAF, NASA1984 Forward-swept wing [42]
X-30 NASP 2.jpg X-30 NASP Rockwell NASA, DARPA, USAF1993 Single-stage-to-orbit spaceplane [43] Canceled and never built.
Rockwell-MBB X-31 landing.JPG X-31 Rockwell-MBBDARPA, USAF, BdV 1990 Thrust vectoring supermaneuverability [44]
X-32A BoeingUSAF, USN, USMC, RAF 2000 Joint Strike Fighter [45]
USAF X32B 250.jpg X-32B 2001
X-33 Venture Star in Orbit.jpg X-33 Lockheed Martin NASA2001Half-scale reusable launch vehicle prototype. [46] Prototype never completed.
Orbital Sciences X34.jpg X-34 Orbital Sciences NASA2001Reusable pilotless spaceplane. [47] Never flew.
X-35.jpg X-35A Lockheed MartinUSAF, USN, USMC, RAF 2000 Joint Strike Fighter [48]
X-35B Steven F. Udvar-Hazy Center.tif X-35B2001First in family to use VTOL. Also used unconventional mode of lift engine (lift fan).
Lockheed F-35 Joint Strike Fighter.jpg X-35C2000
Boeing-X36-InFlight.jpg X-36 McDonnell Douglas NASA199728% scale tailless fighter [49]
Boeing X-37B inside payload fairing before launch.jpg X-37 BoeingUSAF, USSF, NASA2010Reusable orbital spaceplane [50] Drop test performed in 2006. Seven flights to space since 22 April 2010
ISS Crew Return Vehicle.jpg X-38 Scaled Composites NASA1998Lifting body Crew Return Vehicle [51]
X-39 UnknownUSAFFuture Aircraft Technology Enhancements (FATE) program. [52] Designation never officially assigned. [31]
Boeing X40A.jpg X-40A BoeingUSAF, NASA199880% scale Space Maneuver Vehicle X-37 prototype. [53]
Early CAV concept 1997-98 NSSRM.jpg X-41 UnknownUSAFManeuvering re-entry vehicle. [54]
X-42 UnknownUSAFExpendable liquid propellant upper-stage rocket. [55]
X-43 NASA.jpg X-43 Hyper-X Micro-Craft NASA2001Hypersonic Scramjet [56]
X-44 Manta artistic impression.JPG X-44 MANTA Lockheed MartinUSAF, NASA2000 F-22-based Multi-Axis No-Tail Aircraft thrust vectoring [57] Canceled, never flew.
Boeing X-45A UCAV.jpg X-45 BoeingDARPA, USAF2002 Unmanned combat air vehicle (UCAV) [58]
X46.jpg X-46 BoeingDARPA, USN2003 Unmanned combat air vehicle (UCAV). [59] Naval use. Canceled, never flew.
X-47A rollout.jpg X-47A Pegasus Northrop GrummanDARPA, USN2003 Unmanned combat air vehicle (UCAV) [60] Naval use.
X-47B operating in the Atlantic Test Range (modified).jpg X-47B Northrop GrummanDARPA, USN2011UCAVNaval use.
X-47C Northrop GrummanUSAFManned bomberProposal for a new-generation strategic bomber. Design only.
ED06-0198-62.jpg X-48 BoeingNASA2007 Blended Wing Body (BWB) [61]
Piasecki X-49A.jpg X-49 SpeedHawk Piasecki US Army2007 Compound helicopter Vectored Thrust Ducted Propeller (VTDP) testbed. [62]
X-50 Dragonfly BoeingDARPA2003 Canard Rotor/Wing [63]
X51waverider.jpg X-51 Waverider BoeingUSAF2010 [64] Hypersonic scramjet [65]
—X-52————Number skipped to avoid confusion with Boeing B-52 Stratofortress. [31]
X-53 Active Aeroelastic Wing NASA test aircraft EC03-0039-1.jpg X-53 BoeingNASA, USAF2002Active Aeroelastic Wing [66]
X-54 Gulfstream NASALow-noise supersonic transport [67] in development.
Lockheed Martin X-55 ACCA 001.jpg X-55 Lockheed MartinUSAF2009Advanced Composite Cargo Aircraft (ACCA) [68]
Lockheed Martin X-56A.jpg X-56 Lockheed MartinUSAF/NASA2013Active flutter suppression and gust load alleviationPart of the high-altitude, long-endurance (HALE) reconnaissance aircraft program. [69]
X57-Maxwell-CGI.jpg X-57 Maxwell ESAero/Tecnam NASA2023Low emission plane powered entirely by electric motors [70] Part of NASA's Scalable Convergent Electric Propulsion Technology Operations Research project [70] (SCEPTOR). Cancelled in 2023, never flew.
—X-58————Number skipped; slot apparently assigned to Kratos XQ-58 Valkyrie. [71]
NASA's X-59 Sits on Ramp (AFRC2023-0198-03).jpg X-59 Quesst Lockheed MartinNASA2024Prototype quiet supersonic transport aircraft [72]
X-60 Generation Orbit Launch Services USAF Air-launched rocket for hypersonic flight research [73]
GremlinsFlightTestNovember2019.jpg X-61 Gremlins Dynetics DARPA2020Air-launched and air-recoverable reconnaissance unmanned air vehicle (UAV) [74] [75]
X-62 VISTA.jpg X-62 VISTA Lockheed Martin/CalspanUSAF2021Variable In-flight Simulator Test Aircraft.First flew in 1993 as the NF-16D (for the MATV program). Designated the X-62A during a major research system upgrade in 2021. Assigned to the USAF Test Pilot School. [76]
—X-63————Number skipped
—X-64————Number skipped
X-65 by DARPA.jpg X-65 CRANE Aurora Flight Sciences DARPA2025Control of Revolutionary Aircraft with Novel Effectors [77]
TTBW concept.jpg X-66 Boeing NASA2028Transonic Truss-Braced Wing [78]

See also

Notes

  1. ↑ For example, the Piasecki PA-97
  2. ↑ For example, the NASA AD-1 and Bell XV-15
  3. ↑ For example, the Northrop Tacit Blue

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References

  1. ↑ "D-558-I" NASA Dryden Fact Sheets. NASA. Accessed May 8, 2010.
  2. 1 2 Miller 1983, p.9.
  3. ↑ Miller 1983, pp.15-17.
  4. ↑ "X-Planes Experimental Aircraft". Federation of American Scientists . Retrieved 1 June 2012.
  5. ↑ Miller 1983, p.13.
  6. ↑ Miller 2001, p. 209
  7. ↑ First Generation X-1 (fact sheet), Dryden: NASA , retrieved 8 May 2010.
  8. ↑ Jenkins, Landis & Miller 2003, p. 14,15,17,18,24.
  9. ↑ A history of the Joint Strike Fighter Program, UK: Martin-Baker, January 2010, archived from the original on 30 December 2010.
  10. ↑ Jenkins, Landis & Miller 2003, p. 5–7.
  11. ↑ Jenkins, Landis & Miller 2003, p. 8.
  12. ↑ Jenkins, Landis & Miller 2003, p. 9.
  13. ↑ Jenkins, Landis & Miller 2003, p. 10.
  14. ↑ Jenkins, Landis & Miller 2003, p. 11.
  15. ↑ Jenkins, Landis & Miller 2003, p. 12.
  16. ↑ Miller 1983.
  17. ↑ Jenkins, Landis & Miller 2003, p. 13.
  18. ↑ Jenkins, Landis & Miller 2003, p. 14.
  19. ↑ Jenkins, Landis & Miller 2003, p. 15.
  20. ↑ Jenkins, Landis & Miller 2003, p. 16.
  21. ↑ Jenkins, Landis & Miller 2003, p. 17.
  22. ↑ Jenkins, Landis & Miller 2003, p. 18.
  23. ↑ Jenkins, Landis & Miller 2003, p. 19.
  24. ↑ Jenkins, Landis & Miller 2003, p. 20.
  25. ↑ Jenkins, Landis & Miller 2003, p. 21–22.
  26. ↑ Jenkins, Landis & Miller 2003, p. 23.
  27. ↑ "X-16". Global security, accessed 11 May 2010.
  28. ↑ Jenkins, Landis & Miller 2003, p. 24.
  29. ↑ Jenkins, Landis & Miller 2003, p. 25.
  30. ↑ Jenkins, Landis & Miller 2003, p. 26.
  31. 1 2 3 4 Parsch 2024, "Missing Designations"
  32. ↑ Jenkins, Landis & Miller 2003, p. 27.
  33. ↑ Jenkins, Landis & Miller 2003, p. 28.
  34. ↑ Jenkins, Landis & Miller 2003, p. 29.
  35. ↑ Jenkins, Landis & Miller 2003, p. 30.
  36. ↑ Jenkins, Landis & Miller 2003, p. 31.
  37. ↑ Jenkins, Landis & Miller 2003, p. 32.
  38. ↑ Jenkins, Landis & Miller 2003, p. 33.
  39. ↑ Jenkins, Landis & Miller 2003, p. 34.
  40. ↑ Jenkins, Landis & Miller 2003, p. 35.
  41. ↑ Jenkins, Landis & Miller 2003, p. 36.
  42. ↑ Jenkins, Landis & Miller 2003, p. 37.
  43. ↑ Jenkins, Landis & Miller 2003, p. 38.
  44. ↑ Jenkins, Landis & Miller 2003, p. 39.
  45. ↑ Jenkins, Landis & Miller 2003, p. 40–41.
  46. ↑ Jenkins, Landis & Miller 2003, p. 42.
  47. ↑ Jenkins, Landis & Miller 2003, p. 43.
  48. ↑ Jenkins, Landis & Miller 2003, p. 44–45.
  49. ↑ Jenkins, Landis & Miller 2003, p. 46.
  50. ↑ Jenkins, Landis & Miller 2003, p. 47.
  51. ↑ Jenkins, Landis & Miller 2003, p. 48.
  52. ↑ Jenkins, Landis & Miller 2003, p. 49.
  53. ↑ Jenkins, Landis & Miller 2003, p. 50.
  54. ↑ Jenkins, Landis & Miller 2003, p. 51.
  55. ↑ Jenkins, Landis & Miller 2003, p. 52.
  56. ↑ Jenkins, Landis & Miller 2003, p. 53.
  57. ↑ Jenkins, Landis & Miller 2003, p. 54.
  58. ↑ Jenkins, Landis & Miller 2003, p. 55.
  59. ↑ Jenkins, Landis & Miller 2003, p. 56.
  60. ↑ Jenkins, Landis & Miller 2003, p. 57.
  61. ↑ Jenkins, Landis & Miller 2003, p. 58.
  62. ↑ Parsch 2024, "DOD 4120.15-L"
  63. ↑ Jenkins, Landis & Miller 2003, p. 60.
  64. ↑ "X-51 Waverider makes historic hypersonic flight". US Air Force Public Affairs. 26 May 2010. Retrieved 27 May 2010.
  65. ↑ "X-51 Scramjet Engine Demonstrator - WaveRider" globalsecurity.org. Accessed 2010-05-11.
  66. ↑ Jordan 2006
  67. ↑ 412015-L
  68. ↑ Kaufman 2009
  69. ↑ Norris 2012
  70. 1 2 Harrington, J.D.; Kamlet, Matt; Barnstorff, Kathy (17 June 2016). "NASA Hybrid Electric Research Plane Gets X Number, New Name". NASA.gov. NASA. Retrieved 17 June 2016.
  71. ↑ The Air Force Valkyrie Drone, a Sidekick for Human-Piloted Planes, Will Fly This Year
  72. ↑ Jim, Banke (27 June 2018). "NASA's Experimental Supersonic Aircraft Now Known as X-59 QueSST". NASA. Retrieved 28 June 2018.
  73. ↑ "U.S. Air Force Designates GO1 Hypersonic Flight Research Vehicle as X-60A". generationorbit.com. 4 October 2018. Retrieved 4 October 2018.
  74. ↑ "Earthquake damage delays Gremlins trial". Flight International. 24 September 2019. Retrieved 28 October 2019.
  75. ↑ "Dynetics X-61A Gremlins makes first flight, but destroyed after parachute fails". Flight International. 17 January 2020. Retrieved 13 February 2020.
  76. ↑ Giancarlo Casem (30 Jul 2021) NF-16D VISTA becomes X-62A, paves way for Skyborg autonomous flight tests
  77. ↑ Hadley, Greg (16 May 2023). "Meet the X-65: DARPA's New Plane Has No External Control Surfaces". Air & Space Forces Magazine. Retrieved 29 May 2023.
  78. ↑ O’Shea, Claire (12 June 2023). "Next Generation Experimental Aircraft Becomes NASA's Newest X-Plane". NASA. Retrieved 13 June 2023.

Bibliography

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