SpaceX Draco

Summary

SpaceX Draco
Draco In-space Firing.png
A SpaceX Dragon spacecraft approaching the International Space Station fires one of its 16 Draco thrusters.
Country of originUnited States
ManufacturerSpaceX
ApplicationReaction control system
Liquid-fuel engine
PropellantNTO / MMH[1]
Performance
Thrust (vac.)400 N (90 lbf)[1]
Isp (vac.)300 s (2.9 km/s)
Used in
SpaceX Dragon

The SpaceX Draco is a family[original research?] of hypergolic liquid rocket engines designed and built by SpaceX for use in their space capsules. Two engine types have been built to date: Draco and SuperDraco.

The original Draco thruster is a small rocket engine for use on the Dragon spacecraft.[2][3][4]

SuperDraco is derived from Draco,[citation needed] and utilizes the same storable (non-cryogenic) hypergolic propellant as the small Draco thrusters, but is much larger and delivers over 100 times the thrust. SuperDraco engines are being used on the Crew Dragon spacecraft to provide launch-escape capability to low Earth orbit.

Draco and SuperDraco combine the functions of a reaction control system and main propulsive engine.[citation needed]

Draco

Draco thrusters generate 400 newtons (90 pounds-force) of thrust using a storable propellant mixture of monomethyl hydrazine fuel and nitrogen tetroxide oxidizer. The Draco thrust is comparable to the Marquardt R-4D engine developed for the Apollo Service and Lunar Modules in the 1960s and used for apogee/perigee maneuvers, orbit adjustment, and attitude control.

Eighteen Draco thrusters are used on the Dragon spacecraft for attitude control and maneuvering.[1]

SuperDraco

On February 1, 2012 SpaceX announced that it had completed the development of a new, more powerful storable-propellant rocket engine, this one called SuperDraco. This high-thrust hypergolic engine—about 200 times larger than the Draco RCS thruster hypergolic engine—offers deep throttling ability and just like the Draco thruster, has multiple restart capability and uses the same shared hypergolic propellants. Its primary purpose is for SpaceX's LAS (launch abort system) on the Dragon spacecraft. According to the NASA press release, the engine has a transient from ignition to full thrust of 100 ms.[5] During launch abort, eight SuperDracos fire for 5 seconds at full thrust.[citation needed] The development of the engine was partially funded by NASA's CCDev 2 program.

SuperDracos are used on both the Crew Dragon[6] and were used on the SpaceX DragonFly, a prototype low-altitude test article that was used[when?] for flight testing various aspects of the propulsive-landing technology. While the engine is capable of 73,000 newtons (16,400 lbf) of thrust, during use for DragonFly testing, the engines were planned to be throttled to 68,170 newtons (15,325 lbf) to maintain vehicle stability.[7] First firing of all 8 Super Draco engines took place on 6 May 2015 at 9am EST at the SpaceX Crew Dragon Pad Abort Test.[8][9]

SuperDraco engines are capable of being restarted many times, and have the capability to deeply reduce their thrust providing precise control during propulsive landing of the Dragon capsule.[10] SpaceX have since announced they will not be using propulsive landing on the Dragon 2.[11]

As of 2015, SuperDraco is the third most powerful engine developed by SpaceX, approximately 200 times[5] more powerful than the Draco RCS thruster engines, and only outmatched by the Raptor and Merlin. By comparison, it is more than twice as powerful as the Kestrel engine that was used in SpaceX's Falcon 1 launch vehicle second stage, and about 1/9 the thrust of a Merlin 1D engine.[original research?]

In addition to the use of the SuperDraco thrusters for powered-landings on Earth, NASA's Ames Research Center studied the feasibility of a Dragon-derived Mars lander for scientific investigation until 2017.[12] Preliminary analysis indicated that the final deceleration needed would be within the retro-propulsion SuperDraco thruster capabilities.[12][13][needs update]

See also

References

  1. ^ a b c "SpaceX Updates — December 10, 2007". SpaceX. 2007-12-10. Archived from the original on 2011-01-04. Retrieved 2010-02-03.
  2. ^ "SpaceX Draco Thruster Performs Long-Duration Firing and Restart" (Press release). SpaceX. December 9, 2008. Retrieved July 17, 2014.
  3. ^ "Falcon 9 Launch Vehicle Payload User's Guide, 2009" (PDF). SpaceX. 2009. Archived from the original (PDF) on April 29, 2011. Retrieved 2010-02-03.
  4. ^ "Falcon 9 Users Guide Rev 2" (PDF). SpaceX. 21 October 2015. Archived from the original (PDF) on 14 March 2017. Retrieved 14 January 2016.
  5. ^ a b "SpaceX Test Fires Engine Prototype for Astronaut Escape System". NASA. 2012-02-01. Retrieved 2012-02-01.
  6. ^ "Dragon". SpaceX. Retrieved 3 September 2015.
  7. ^ James, Michael; Salton, Alexandria; Downing, Micah (November 12, 2013), Draft Environmental Assessment for Issuing an Experimental Permit to SpaceX for Operation of the Dragon Fly Vehicle at the McGregor Test Site, Texas, May 2014 – Appendices (PDF), Blue Ridge Research and Consulting, LCC, p. 12
  8. ^ SpaceX Pad Abort Test. YouTube. 8 May 2015. Retrieved 3 September 2015.
  9. ^ "Crew Dragon Completes Pad Abort Test". SpaceX. Retrieved 3 September 2015.
  10. ^ "SuperDraco Thruster Powers Revolutionary Launch Escape System (Rocket Thruster Test)". Satnews Daily. 2014-05-27. Retrieved 2014-05-28.
  11. ^ "SpaceX drops plans for powered Dragon landings - SpaceNews.com". SpaceNews.com. 2017-07-19. Retrieved 2018-06-04.
  12. ^ a b NASA; SpaceX (October 31, 2011). "Red Dragon" (PDF). 8m.net. Retrieved 2012-05-14.
  13. ^ NASA Ames Research Center (1 November 2011). "NASA ADVISORY COUNCIL (NAC) - Science Committee Report" (PDF). Archived from the original (PDF) on 2013-01-20. Retrieved 2012-05-01.

External links

  • Official SpaceX announcement and test video
  • Multiple Draco Test Firings, Test firing video of a set of five Draco thrusters for various intervals, SpaceX, 2010-01-27.