Aerojet General X-8

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X-8 Aerobee
Aerojet X-8 rocket
Role Upper Atmospheric Research Vehicle, X-plane
Manufacturer Aerojet General
First flight 2 December 1949[1]
Primary users NACA/NASA
United States Air Force
United States Navy
Number built 108
Variants Aerobee

The Aerojet General X-8 was an unguided, spin-stabilized sounding rocket designed to launch a 150 lb (68 kg) payload to 200,000 feet (61.0 km).[2][3] The X-8 was a version of the prolific Aerobee rocket family.[3][4][5]

Towards the end of World War II, the US Army and the California Institute of Technology's Jet Propulsion Laboratory had developed a meteorological sounding rocket, the WAC Corporal.[6] The U.S. Army had also captured enough parts to assemble perhaps 100 German V-2 guided missiles. The Army determined that its Project Hermes would be extended to assemble and launch a number of the V-2s for military, technological and scientific purposes.[7] Many of the V-2 components were damaged or useless.[8][9] Thus the initial intent of the Army was to launch only 20 missiles.[10]

The Army was to make space available on the V-2s for upper atmosphere research. Due to the limited number of V-2s, originally planned design of several competing sounding rockets continued. Jet Propulsion Laboratory initially favored its WAC Corporal despite its inadequacy.[11] The competing rockets were the Applied Physics Laboratory's Aerobee and the Naval Research Laboratory's Neptune (Viking).[12] The Army determined that it would refurbish and manufacture components as necessary to launch many more V-2s than originally intended, making most available for science.[13]

The Aerobee was developed in response to the need for a sounding rocket to replace the dwindling numbers of V-2s.[14] Design and initial development of the Aerobee occurred between June 1946 and November 1947.[15]

The first Aerobees, the Navy RTV-N-8a1 and Army Signal Corps XASR-SC-1, used the Aerojet XASR-1 2,600 lbf (12 kN) thrust air-pressurized engine. Aerojet's XASR-1 was developed from the 1,500 lbf (7 kN) thrust WAC-1 engine of the WAC Corporal sounding rocket.[16] The USAF RTV-A-1 (X-8), Navy RTV-N-10 and Army XASR-SC-2s used the Aerojet XASR-2 2,600 lbf (12 kN) thrust helium pressurized engine.[17] In 1949 the Air Force instigated the development of a more powerful Aerojet engine to replace the 2,600 lb.-thrust XASR-2. This was the 4,000 lbf (18 kN) thrust helium-pressurized AJ 10-25.[18] The USAF X-8A (RTV-A-1a) and USN RTV-N-10a used the seminal Aerojet AJ-10-25 (Air Force) or AJ-10-24 (Navy).[18][19]

The Army Air Force's Air Research and Development Command, needing its own research programs, initiated Project MX-1011 and ordered 33 AJ-10-25 powered Aerobees as RTV-A-1s.[20][21] That designation was later changed to X-8.[22] Ultimately the rocket was renamed again as RM-84.[23] The number of X-8s flown came to 60 including 28 X-8s (RTV-A-1), 30 X-8As (RTVM-A-1a), 1 X-8B (RTV-A-1b) with a 2,600 lbf (12 kN) thrust XASR-2 chemically pressurized engine, and 1 X-8C (RTV-A-1c) with a 4,000 lbf (18 kN) thrust AJ 10-25s helium pressurized engine with no booster.[24][25] The three X-8D with 4,000 lbf (18 kN) thrust AJ 10-25, were never flown.[26] A Navy experimental launch of a stretched Aerobee, the RTV-N-10b resulted in both services requesting improved Aerobees, known generically as Aerobee-Hi.[27][28]

Operational history[edit]

At launch, an 18,000 lbf (80 kN) thrust Aerojet 2.5KS18,000G solid rocket booster fired for 2.5 seconds.[29] After booster jettison, a 2,600 lbf (12 kN) thrust XASR-2 liquid fuel rocket burned for up to 40 seconds (depending on desired apogee).[29][30] The X-8 recovery sequence was normally started as the rocket descended through about 200,000 ft (60,960.0 m) feet when the fins were blown off to induce a drag producing tumble.[31] At about 20,000 ft (6,096.0 m) the nose cone was blown off the rocket and returned to Earth by parachute.[32] The baseline X-8 measured 20.2 ft (6.2 m) in length and measured 5.25 ft (1.6 m) across the fins. A X-8A reached a maximum altitude of 138.4 miles (222.7 km) Another reached a speed of Mach six.[33] The payloads of the X-8s varied, averaging about 150 lbs.[27] There were 30 X-8s, 30 X-8As, 1 X-8B, 2 X8-Cs and 3 X-8Ds delivered to the Air Force.[29]

The first RTV-A-1 (X-8) flight was USAF-1, flown at Holloman Air Force Base (adjacent to the White Sands Proving Ground). USAF-1 was launched by an Air Force crew commanded by Major Phillip Calhoun, the Aerobee Project Officer, on 2 December 1949.[34] USAF-1 reached an altitude of 59.7 miles (96.1 km) and carried three experiments; a Solar Radiation Soft X-Ray detector for the Air Force Cambridge Research Center, a Pressure-Temperature study for Boston University, and a Color Earth Photography experiment for the Wright-Patterson Air Force Base Equipment Laboratory. Rocket performance was good. Telemetry returned some data. The X-Ray detector foils ruptured and returned no data. Parachute failure resulted in the nose cone containing the experiments to be lost. The nose cone was found in July 1950, the film was destroyed.[35]

The next four flights saw the nose cone recovery parachutes fail.[36]

USAF-6, was a more typical X-8 Mission. It carried a payload of Pressure-Temperature detectors for the University of Michigan, an Air Force Cambridge Center multipurpose beacon, 6 channel PPM-AM system, a Ten channel data recorder supplied by Tufts College, and a camera to photograph a Sperry aspect gyro for the University of Michigan. USAF-6 reached an altitude of 57.5 miles (92.5 km) before a flawless recovery.[37]

From December 1949 until the last X-8A flight on 11/12/1956, the X-8s (RTV-A-1/RTV-A-1a)s flew a great variety of experiments. Typical payloads were solar radiation, temperature, pressure, photography, sky brightness, atmosphere composition, winds, airglow, rocket performance, biological experiments, air density, day airglow, ionosphere, sodium studies, nitric oxide to produce a sporadic E layer, nitric oxide attempt to recombine atomic oxygen, sodium cloud ionization, solar spectrum and atmospheric composition.[38] All but the last X-8 mission were flown from Holloman AFB. The last X-8 was flown for the Signal Corps Electronic Laboratory from Fort Churchill, Canada on 11/12/1956 and studied temperature and winds.[27] After the X-8s Air Force Aerobees were known by their engine model numbers, either AJ-10-27 or AJ-10-34.[39]

Variants[edit]

  • X-8 - 30
  • X-8A - 30
  • X-8B - 1
  • X-8C - 2
  • X-8D - 3

Specifications (general)[edit]

Data from The X-Planes: X-1 to X-45.[1]

General characteristics

  • Crew: unmanned
  • Length: 20 ft 1.5 in (6.134 m)
  • Wingspan: 5 ft 3 in (1.60 m)
  • Wing area: 36 sq ft (3.3 m2)
  • Empty weight: 135 lb (61 kg)
  • Gross weight: 1,097 lb (498 kg)
  • Useful load: 150–300 lbs (68–136 kg)
  • Diameter: 15 in (38 cm)

Performance

  • Maximum speed: 4,020 mph (6,470 km/h, 3,490 kn)
  • Range: 20 mi (32 km, 18 nmi)
  • Service ceiling: 800,000 ft (240,000 m)

See also[edit]

Related development

References[edit]

  1. ^ a b Miller, Jay (2001). "Aerojet General X-8A, X-8B, X-8C, and X-8D Aerobee". The X-Planes: X-1 to X-45. Hinckley, UK: Midland. ISBN 1-85780-109-1.
  2. ^ Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. p. 56.
  3. ^ a b Miller, Jay, The X-Planes, 1988, Arlington, Texas: Aerofax, Inc., ISBN 0-517-56749-0, page 81
  4. ^ Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. pp. 55–57, 62, Table 4-1.
  5. ^ Smith, Charles P. Jr. (February 1958). Naval Research Laboratory Report No. 4276 Upper Atmospheric Research Report Number XXI, Summary of Upper Atmosphere Rocket Research Firings. Vol. 2. Washington D.C.: Naval Research Loboratory. pp. 46, 293. Archived from the original (pdf) on 11 March 2016. Retrieved 10 March 2016.
  6. ^ Eckles, Jim (2013). Pocket Full of Rockets. Las Cruces, New Mexico: Fiddlebike Partnership. pp. 165–166. ISBN 9781492773504.
  7. ^ DeVorkin, David H. (1992). Science With A Vengeance. New York: Smithsonian Institution (Springer-Verlag). pp. 48, 61–62. ISBN 1-56347-649-5.
  8. ^ Kennedy, Gregory P. (2009). The Rockets and Missiles of White Sands Proving Ground. Atglen, PA.: Schiffer Publishing, Ltd. pp. 34–36. ISBN 978-0-7643-3251-7.
  9. ^ White, L. D. (September 1952). Final Report, Project Hermes V-2 Missile Program. Schnectady, New York: Guided Missile Department, Aeronautic and Ordnance Systems Division, Defense Products Group, General Electric. p. 19.
  10. ^ DeVorkin, David H. (1992). Science With A Vengeance. New York: Smithsonian Institution (Springer-Verlag). p. 62. ISBN 1-56347-649-5.
  11. ^ DeVorkin, David H. (1992). Science With A Vengeance. New York: Smithsonian Institution (Springer-Verlag). pp. 168–170. ISBN 1-56347-649-5.
  12. ^ DeVorkin, David H. (1992). Science With A Vengeance. New York: Smithsonian Institution (Springer-Verlag). pp. 171, 175. ISBN 1-56347-649-5.
  13. ^ DeVorkin, David H. (1992). Science With A Vengeance. New York: Smithsonian Institution (Springer-Verlag). p. 66. ISBN 1-56347-649-5.
  14. ^ Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. p. 55.
  15. ^ Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. p. 57.
  16. ^ Sutton, George P. (2006). History of Liquid Propellant Rocket Engines. Reston, Virginia: American Institute of Aeronautics and Astronautics. p. 371. ISBN 1-56347-649-5.
  17. ^ Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. p. 60.
  18. ^ a b Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. p. 62.
  19. ^ The AJ-10 series of rocket engines spanned 49 different versions and the history of space exploration. From the Aerobee and Vanguard, to the Able and Delta SLVs, Titan SLVs, the Apollo Service Module engine and the Space Shuttle Orbital Maneuver engine. Sutton, George P., History of Liquid Propellant Rocket Engines, American Institute of Aeronautics and Astronautics, Reston, Virginia, 2006, pages 371–377, ISBN 1-56347-649-5
  20. ^ Parsch, Andreas. "MX-1000 to MX-1499 Listing". Directory of U.S. Military Rockets and Missiles. pp. Appendix 1. Retrieved 2016-03-16.
  21. ^ Parsch, Andreas. "Air Force designations 1951 - 1955". Directory of U.S. Military Rockets and Missiles. pp. Appendix 1. Retrieved 2016-03-16.
  22. ^ Parsch, Andreas. "Air Force designations 1951 - 1955". Directory of U.S. Military Rockets and Missiles. pp. Appendix 1. Retrieved 2016-03-16.
  23. ^ Parsch, Andreas. "\Air Force designations 1951 - 195". Directory of U.S. Military Rockets and Missiles. pp. Appendix 1. Retrieved 2016-03-16.
  24. ^ Miller, Jay, The X-Planes, 1988, Arlington, Texas: Aerofax, Inc., ISBN 0-517-56749-0, page 82
  25. ^ Includes 1 flown for the SCEL as SC-31 and another flown for the same agency as SM1.01.Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. pp. 68–69.
  26. ^ Miller, Jay, The X-Planes, 1988, Arlington, Texas: Aerofax, Inc., ISBN 0-517-56749-0, page 80
  27. ^ a b c Miller, Jay (1988). The X-Planes X-1 to X-31. Arlington, Texas: Aerofax (for Orion Books). p. 82. ISBN 0-517-56749-0.
  28. ^ Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. p. 68.
  29. ^ a b c Miller, Jay (1988). The X-Planes X-1 to X-31. Arlington, Texas: Aerofax (for Orion Books). p. 80. ISBN 0-517-56749-0.
  30. ^ "Aerojet General RM-84/PWN-2 Aerobee-Hi (and earlier Aerobee variants)". Directory of U.S. Military Rockets and Missiles. Retrieved 2015-08-14.
  31. ^ "We Develop Missiles, Not Air!" The Legacy of Early Missile, Rocket, Instrumentation, and Aeromedical Research Development at Holloman Air Force Base, Project Manhigh, Holloman Air Force Base Cultural Resources Publication No. 2. Holloman AFB, NM.: United States Air Force. June 1995. p. 106.
  32. ^ "We Develop Missiles, Not Air!" The Legacy of Early Missile, Rocket, Instrumentation, and Aeromedical Research Development at Holloman Air Force Base, Project Manhigh, Holloman Air Force Base Cultural Resources Publication No. 2. Holloman AFB, NM.: United States Air Force. June 1995. p. 106.
  33. ^ Miller, Jay (1988). The X-Planes X-1 to X-31. Arlington, Texas: Aerofax (for Orion Books). p. 81. ISBN 0-517-56749-0.
  34. ^ 'We Develop Missiles, Not Air!' The Legacy of Early Missile, Rocket, Instrumentation, and Aeromedical Research Development at Holloman Air Force Base, Project Manhigh, Holloman Air Force Base Cultural Resources Publication No. 2. Holloman AFB, NM.: United States Air Force. June 1995. p. 108.
  35. ^ Smith, Charles P. Jr. (February 1958). Naval Research Laboratory Report No. 4276 Upper Atmospheric Research Report Number XXI, Summary of Upper Atmosphere Rocket Research Firings. Washington D.C.: Naval Research Laboratory. pp. 46–47 (Aerobe USAF-1). Archived from the original (pdf) on 11 March 2016. Retrieved 10 March 2016.
  36. ^ Smith, Charles P. Jr. (February 1958). Naval Research Laboratory Report No. 4276 Upper Atmospheric Research Report Number XXI, Summary of Upper Atmosphere Rocket Research Firings. Washington D.C.: Naval Research Laboratory. pp. 48–55 (Aerobe USAF-2 to 5). Archived from the original (pdf) on 11 March 2016. Retrieved 10 March 2016.
  37. ^ Smith, Charles P. Jr. (February 1958). Naval Research Laboratory Report No. 4276 Upper Atmospheric Research Report Number XXI, Summary of Upper Atmosphere Rocket Research Firings. Washington D.C.: Naval Research Laboratory. pp. 56–57 (Aerobe USAF-6). Archived from the original (pdf) on 11 March 2016. Retrieved 10 March 2016.
  38. ^ Smith, Charles P. Jr. (February 1958). Naval Research Laboratory Report No. 4276 Upper Atmospheric Research Report Number XXI, Summary of Upper Atmosphere Rocket Research Firings. Washington D.C.: Naval Research Laboratory. pp. 46–186 (Aerobe USAF-1). Archived from the original (pdf) on 11 March 2016. Retrieved 10 March 2016.
  39. ^ Van Allen, James A. & Townsend, Jr. (1959). "Chapter 4:The Aerobee Rocket". In Newell, Homer E. (ed.). Sounding Rockets. McGraw-Hill Book Company. pp. Table 4-3.

External links[edit]