Jump to content

SuperDraco

From Wikipedia, the free encyclopedia
SuperDraco
A pair of SuperDraco rocket engines atSpaceX Hawthorne facility
Country of originUnited States
ManufacturerSpaceX
ApplicationLaunch escape system,propulsive landing[1]
StatusOperational
Liquid-fuel engine
PropellantNTO[2][3]/MMH[2][3]
Performance
Thrust, sea-level71 kN (16,000 lbf),[4]individually
32,000lbf, dual-engine cluster[5]
Chamberpressure6.9 MPa (1,000 psi)[1]
Specific impulse,sea-level235 s (2.30 km/s)[6]
Burn time25 seconds[6]
Propellant capacity1,388 kg (3,060 lb)[3]
Used in
SpaceX Dragon 2- Crew,DragonFly

SuperDracois ahypergolic propellantrocket enginedesigned and built bySpaceX.It is part of theSpaceX Dracofamily of rocket engines. A redundant array of eight SuperDraco engines providesfault-tolerantpropulsion for use as alaunch escape systemfor theSpaceX Dragon 2,a passenger-carryingspace capsule.

SuperDraco rocket engines utilize astorable(non-cryogenic) hypergolicpropellantwhich allows the engines to be fired many months after fueling and launch. They combine the functions of both areaction control systemand amain propulsive engine.Hypergolic fuels do not require an external source of ignition, providing increased reliability for the spacecraft.[7]

The engines are used oncrew transportflights tolow Earth orbit,and were also projected to be used for entry, descent and landing control of the now-canceledRed DragontoMars.

SuperDracos are used on theSpaceX Dragon 2crew-transportingspace capsuleand were used on theDragonFly,a prototype low-altitude reusable rocket that was used forflight testingvarious 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 werethrottledto 68,170 newtons (15,325 lbf) to maintain vehicle stability.[6]

History[edit]

On February 1, 2012 SpaceX announced that it had completed the development of a new, more powerful version of astorable-propellantrocket engine, this one calledSuperDraco.This high-thrusthypergolicengine—about 200 times more powerful than theDracoRCS thruster hypergolic engine—offers deep throttling ability,[8]and just like the Draco thruster, was designed to provide multiple restart capability and use the same shared hypergolic propellants as Draco. Its primary purpose was to be for SpaceX'slaunch abort system(LAS) on the Dragon spacecraft. According to a NASA press release, the engine has a transient from ignition to full thrust of 100 ms. During launch abort, eight SuperDracos were expected to fire for 5 seconds at full thrust. The development of the engine was partially funded by NASA'sCCDev 2program.

Name: Draco comes from the Greek drakōn for dragon.Draco (constellation)is a constellation (the Dragon) in the polar region of the Northern Hemisphere near Cepheus and Ursa Major.

Design[edit]

SuperDraco engines use astorable propellantmixture ofmonomethylhydrazine[2]fuelanddinitrogen tetroxide[2]oxidizer.They are capable of being restarted many times, and have the capability todeeply reduce their thrustproviding precise control duringpropulsive landingof the Dragon capsule.[9]

SuperDraco is the third most powerful engine developed by SpaceX. It is approximately 200 times[10]as powerful as the Draco thruster engine. By comparison, it is more than twice as powerful as theKestrelengine that was used in SpaceX'sFalcon 1launch vehiclesecond stage,about 1/9 the thrust of aMerlin 1Dengine, and expected to be 1/26th as powerful as theSpaceX Raptorengine.

In addition to the use of the SuperDraco thrusters for powered-landings on Earth,NASA's Ames Research Centerwas studying the feasibility of aDragon-derived Mars landerfor scientific investigation until 2017.[11]Preliminary analysis in 2011 indicated that the final deceleration would be within the retro-propulsion SuperDraco thruster capabilities.[11][12]

SuperDraco is designed to be highlythrottleable,from 100 to 20% of full thrust.[8]This would have been used for precision controllablepropulsive landingsof the Dragon V2 spacecraft.

Engine testing[edit]

SuperDraco test-fire mosaic

The SuperDraco engine development program had an extensivetest programthat spanned several years. As of December 2012,the SuperDraco ground-test engines had been fired a total of 58 times for a total firing-time duration of 117 seconds and SpaceX expressed hope that the test results would exceed the original requirements for the engine.[13]

A second version of the engine was developed in 2013, this one manufactured with3D printingrather than the traditionalcasting technique.By July 2014, the 3D-printed engine combustion chamber had been fired over 80 times, for a total duration of more than 300 seconds, and it likewise completed a full qualification test.[8]

The SuperDraco completed qualification testing in May 2014 – including testing "across a variety of conditions including multiple starts, extended firing durations and extreme off-nominal propellant flow and temperatures."[9]

By January 2015, SpaceX demonstrated the SuperDraco engine pod with full functionality at McGregor, Texas. Four of these engine pods, each containing two SuperDraco engines, will be used in the Dragon 2 crewed spacecraft.[14]

In April 2015, SpaceX and NASA set a timeframe to test a Dragon 2's SuperDraco engines with a pad abort test. The test eventually occurred on May 6, 2015, from a test stand atCape Canaveral Air Force StationSLC-40.[15]and was successful.[16]

On April 20, 2019, the SpaceX Crew Dragon capsule used on DM-1 was destroyed during a test of the SuperDraco engines at Landing Zone 1.[17]

Manufacturing[edit]

On September 5, 2013 Elon Musktweetedan image of a regeneratively cooled SuperDraco rocket chamber emerging from an EOS 3D metal printer, and indicated that it was composed of theInconelsuperalloy.[18]This was later shown to be the production technique for the flight-level engines.

It was announced in May 2014 that the flight-qualified version of the SuperDraco engine is the first[clarification needed]fully3D printedrocket engine.In particular, the engine combustion chamber is printed ofInconel,an alloy of nickel and iron, using a process ofdirect metal laser sintering,and operates at achamber pressure6,900 kilopascals (1,000 psi) at a very high temperature.[clarification needed]The engines are contained in a printed protective nacelle to prevent fault propagation in the event of an engine failure.[1][19][20]

The ability to 3D print the complex parts was key to achieving the low-mass objective of the engine. According to Elon Musk, "It’s a very complex engine, and it was very difficult to form all the cooling channels, the injector head, and the throttling mechanism. Being able to print very high strength advanced alloys... was crucial to being able to create the SuperDraco engine as it is."[21]

The 3D printing process for the SuperDraco engine dramatically reduceslead-timecompared to the traditionalcastparts, and "has superiorstrength,ductility,andfracture resistance,with a lower variability inmaterials properties."[8]

According to Elon Musk, cost reduction through 3D printing is also significant, in particular because SpaceX can print an hourglass chamber where the entire wall consists of internal cooling channels, which would be impossible without additive manufacturing.[22]

See also[edit]

References[edit]

  1. ^abc Bergin, Chris (2014-05-30)."SpaceX lifts the lid on the Dragon V2 crew spacecraft".NASAspaceflight.com.Retrieved2014-05-30.
  2. ^abcd"SpaceX Demonstrates Astronaut Escape System for Crew Dragon Spacecraft".NASA.6 May 2015.Retrieved7 May2015.
  3. ^abc"Archived copy"(PDF).Archived fromthe original(PDF)on 2020-07-18.Retrieved2019-09-24.{{cite web}}:CS1 maint: archived copy as title (link)
  4. ^"SpaceX Completes Qualification Testing of SuperDraco Thruster".2014-05-28.
  5. ^"SuperDraco | Test Fire".YouTube.2015-11-10.
  6. ^abcJames, 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
  7. ^Clark, John (1972).Ignition! An Informal History of Liquid Rocket Propellants.Rutgers University Press. pp. 214–220.ISBN978-0-8135-0725-5.
  8. ^abcd "SpaceX Launches 3D-Printed Part to Space, Creates Printed Engine Chamber for Crewed Spaceflight".SpaceX. 2014-07-31.Retrieved2014-08-01.Compared with a traditionally cast part, a printed [part] has superior strength, ductility, and fracture resistance, with a lower variability in materials properties.... The chamber is regeneratively cooled and printed in Inconel, a high performance superalloy. Printing the chamber resulted in an order of magnitude reduction in lead-time compared with traditional machining – the path from the initial concept to the first hotfire was just over three months. During the hotfire test,... the SuperDraco engine was fired in both a launch escape profile and a landing burn profile, successfully throttling between 20% and 100% thrust levels. To date the chamber has been fired more than 80 times, with more than 300 seconds of hot fire.
  9. ^ab"SuperDraco Thruster Powers Revolutionary Launch Escape System (Rocket Thruster Test)".Satnews Daily.2014-05-27.Retrieved2014-05-28.
  10. ^ "SpaceX Test Fires Engine Prototype for Astronaut Escape System".NASA.2012-02-01.Retrieved2012-02-01.
  11. ^ab"Red Dragon"(PDF),Feasibility of a Dragon-derived Mars lander for scientific and human-precursor investigations,8m.net, October 31, 2011, archived fromthe original(PDF)on 2012-06-16,retrieved2012-05-14
  12. ^ "NASA ADVISORY COUNCIL (NAC) - Science Committee Report"(PDF).Ames Research Center, NASA.1 November 2011. Archived fromthe original(PDF)on 2013-01-20.Retrieved2012-05-01.
  13. ^ Staff (2012-12-14)."NASA's Return On Investment Report"(PDF).Retrieved2015-12-30.
  14. ^"Full functionality of Crew Dragon's SuperDraco jetpacks demonstrated with hotfire test in McGregor, TX".vine.co.Vine.Retrieved24 January2015.
  15. ^Clark, Stephen (21 April 2015)."Dragon pad abort test set for early May".Spaceflight Now.
  16. ^Berger, Eric (2016-04-30)."From zero to 100mph in 1.2 seconds, the SuperDraco thruster delivers".Ars Technica.Retrieved2017-02-04.
  17. ^"SpaceX Crew Dragon spacecraft destroyed in test mishap, company confirms".www.cbsnews.com.Retrieved2019-05-03.
  18. ^@elonmusk (5 September 2013)."SpaceX SuperDraco inconel rocket chamber w regen cooling jacket emerges from EOS 3D metal printer"(Tweet) – viaTwitter.
  19. ^Norris, Guy (2014-05-30)."SpaceX Unveils 'Step Change' Dragon 'V2'".Aviation Week.Archived fromthe originalon 2014-05-31.Retrieved2014-05-30.
  20. ^ Kramer, Miriam (2014-05-30)."SpaceX Unveils Dragon V2 Spaceship, a Manned Space Taxi for Astronauts — Meet Dragon V2: SpaceX's Manned Space Taxi for Astronaut Trips".space.com.Retrieved2014-05-30.
  21. ^Foust, Jeff (2014-05-30)."SpaceX unveils its" 21st century spaceship "".NewSpace Journal.Retrieved2014-05-31.
  22. ^ Elon Musk, Mike Suffradini (7 July 2015).Elon Musk comments on Falcon 9 explosion - Huge Blow for SpaceX (2015.7.7)(video). Archived fromthe originalon 2015-09-06.Retrieved2015-12-30.
Retrieved from "https://en.wikipedia.org/w/index.php?title=SuperDraco&oldid=1217323885"