The SpaceX Draco is a

hypergolic A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other. The two propellant components usually consist of a fuel and an oxidizer. The ...

liquid A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter (the others being solid, gas, a ...

rocket engine A rocket engine uses stored rocket propellants as the reaction mass for forming a high-speed propulsive jet of fluid, usually high-temperature gas. Rocket engines are reaction engines, producing thrust by ejecting mass rearward, in accordanc ...

designed and built by

SpaceX Space Exploration Technologies Corp. (SpaceX) is an American spacecraft manufacturer, launcher, and a satellite communications corporation headquartered in Hawthorne, California. It was founded in 2002 by Elon Musk with the stated goal of ...

for use in their

space capsule A space capsule is an often-crewed spacecraft that uses a blunt-body reentry capsule to reenter the Earth's atmosphere without wings. Capsules are distinguished from other satellites primarily by the ability to survive reentry and return a payl ...

s. 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 A dragon is a reptilian legendary creature that appears in the folklore of many cultures worldwide. Beliefs about dragons vary considerably through regions, but dragons in western cultures since the High Middle Ages have often been depicted as ...

spacecraft.

SuperDraco SuperDraco is a hypergolic propellant rocket engine designed and built by SpaceX. It is part of the SpaceX Draco family of rocket engines. A redundant array of eight SuperDraco engines provides fault-tolerant propulsion for use as a launch escap ...

uses the same storable (non-cryogenic) hypergolic propellant as the small Draco thrusters, but is much larger and delivers over 100 times the

thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that syst ...

. SuperDraco engines are being used on the

Crew Dragon Dragon 2 is a class of partially reusable spacecraft developed and manufactured by American aerospace manufacturer SpaceX, primarily for flights to the International Space Station (ISS). SpaceX has also launched private missions such as Ins ...

spacecraft to provide launch-escape capability in case of a failure in the launch vehicle. Draco and SuperDraco combine the functions of a

reaction control system A reaction control system (RCS) is a spacecraft system that uses thrusters to provide attitude control and translation. Alternatively, reaction wheels are used for attitude control. Use of diverted engine thrust to provide stable attitude cont ...

and main propulsive engine.

Draco

Draco thrusters generate 400 newtons (90

pounds-force The pound of force or pound-force (symbol: lbf, sometimes lbf,) is a unit of force used in some systems of measurement, including English Engineering units and the foot–pound–second system. Pound-force should not be confused with pound-ma ...

) of thrust using a

storable propellant A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the e ...

mixture of

monomethyl hydrazine Monomethylhydrazine (mono-methyl hydrazine, MMH) is a highly toxic, volatile hydrazine derivative with the chemical formula . It is used as a rocket propellant in bipropellant rocket engines because it is hypergolic with various oxidizers such as ...

fuel A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. The concept was originally applied solely to those materials capable of releasing chemical energy but ...

and

nitrogen tetroxide Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russia rocket engineers) as amyl, is the chemical compound N2O4. It is a useful reagent in chemical synthesis. It forms an equilibrium ...

oxidizer An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxid ...

. 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. Sixteen Draco thrusters are used on the

Dragon spacecraft American private space transportation company SpaceX has developed and produced several spacecraft named Dragon. The first family member, now referred to as Dragon 1, flew 23 cargo missions to the ISS between 2010 and 2020 before being retired ...

for

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

and maneuvering.

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. The development of the engine was partially funded by NASA's CCDev 2 program. SuperDracos are used on both the

and were used on the

SpaceX DragonFly The Dragon 2 ''DragonFly'' (Dragon C201) was a prototype suborbital rocket-powered test vehicle for a propulsively-landed version of the SpaceX Dragon 2. ''DragonFly'' underwent testing in Texas at the McGregor Rocket Test Facility in Octo ...

, a prototype low-altitude test article that was used for

flight test Flight testing is a branch of aeronautical engineering that develops specialist equipment required for testing aircraft behaviour and systems. Instrumentation systems are developed using proprietary transducers and data acquisition systems. D ...

ing various aspects of the propulsive-landing technology. While the engine is capable of of thrust, during use for DragonFly testing, the engines were planned to be throttled to to maintain vehicle stability. 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. SuperDraco engines are capable of being restarted many times, and have the capability to deeply reduce their thrust providing precise control during

propulsive landing Landing is the last part of a flight, where a flying animal, aircraft, or spacecraft returns to the ground. When the flying object returns to water, the process is called alighting, although it is commonly called "landing", "touchdown" or ...

of the Dragon capsule. SpaceX have since announced they will not be using propulsive landing on the Dragon 2. , SuperDraco is the third most powerful engine developed by SpaceX, approximately 200 times more powerful than the Draco RCS thruster engines, and only outmatched by the

Raptor Raptor or RAPTOR may refer to: Animals The word "raptor" refers to several groups of bird-like dinosaurs which primarily capture and subdue/kill prey with their talons. * Raptor (bird) or bird of prey, a bird that primarily hunts and feeds on ...

and Merlin. 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. Preliminary analysis indicated that the final deceleration needed would be within the retro-propulsion SuperDraco thruster capabilities.

References

External links

Official SpaceX announcement and test videoMultiple Draco Test Firings
Test firing video of a set of five Draco thrusters for various intervals, SpaceX, 2010-01-27. {{DEFAULTSORT:Draco (Rocket Engine) SpaceX rocket engines Rocket engines using hypergolic propellant Rocket engines using the pressure-fed cycle Rocket engines of the United States

Draco

SuperDraco

See also

References

External links