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 Liquid is a state of matter with a definite volume but no fixed shape. Liquids adapt to the shape of their container and are nearly incompressible, maintaining their volume even under pressure. The density of a liquid is usually close to th ...

rocket engine A rocket engine is a reaction engine, producing thrust in accordance with Newton's third law by ejecting reaction mass rearward, usually a high-speed Jet (fluid), jet of high-temperature gas produced by the combustion of rocket propellants stor ...

designed and built by

SpaceX Space Exploration Technologies Corp., commonly referred to as SpaceX, is an America, American space technology company headquartered at the SpaceX Starbase, Starbase development site in Starbase, Texas. Since its founding in 2002, the compa ...

for use in their

space capsule A space capsule is a spacecraft designed to transport cargo, scientific experiments, and/or astronauts to and from space. Capsules are distinguished from other spacecraft by the ability to survive reentry and return a payload to the Earth's surfa ...

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 Magic (supernatural), magical legendary creature that appears in the folklore of multiple cultures worldwide. Beliefs about dragons vary considerably through regions, but European dragon, dragons in Western cultures since the Hi ...

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

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 ...

. SuperDraco engines are being used on the

Crew Dragon Dragon 2 is a class of partially reusable spacecraft developed, manufactured, and operated by the American space company SpaceX for flights to the International Space Station (ISS) and private spaceflight missions. The spacecraft, which consi ...

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 (spacecraft), thrusters to provide Spacecraft attitude control, attitude control and translation (physics), translation. Alternatively, reaction wheels can be used for at ...

and main propulsive engine.

Draco

Draco thrusters generate 400

newtons The newton (symbol: N) is the unit of force in the International System of Units (SI). Expressed in terms of SI base units, it is 1 kg⋅m/s2, the force that accelerates a mass of one kilogram at one metre per second squared. The unit i ...

(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 ...

) 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 another motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, th ...

mixture of

monomethyl hydrazine Monomethylhydrazine (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 nitrogen tetroxide () a ...

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 (physics), work. The concept was originally applied solely to those materials capable of releasing chem ...

and

nitrogen tetroxide Dinitrogen tetroxide, commonly referred to as nitrogen tetroxide (NTO), and occasionally (usually among ex-USSR/Russian 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 ''electron donor''). In ot ...

. 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 Dragon is a family of spacecraft developed and produced by American private space transportation company SpaceX. The first variant, later named Dragon 1, flew 23 cargo missions to the International Space Station (ISS) between 2010 and 2020 be ...

for

attitude control Spacecraft attitude control is the process of controlling the orientation of a spacecraft (vehicle or satellite) with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, ...

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, a prototype low-altitude test article that was used for flight testing 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 EDT 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 "spla ...

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

and

Merlin The Multi-Element Radio Linked Interferometer Network (MERLIN) is an interferometer array of radio telescopes spread across England. The array is run from Jodrell Bank Observatory in Cheshire by the University of Manchester on behalf of UK Re ...

. 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