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, the engine that expels the propellant is called a reaction engine . Although technically a propellant is the reaction mass used to create thrust, the term "propellant" is often used to describe a substance which contains both the reaction mass and the fuel that holds the energy used to accelerate the reaction mass. For example, the term "propellant" is often used in chemical rocket design to describe a combined fuel/propellant, although the propellants should not be confused with the fuel that is used by an engine to produce the energy that expels the propellant. Even though the byproducts of substances used as fuel are also often used as a reaction mass to create the thrust, such as with a chemical rocket engine, propellant and fuel are two distinct concepts.
92-550: The M-V rocket, also called M-5 or Mu-5 , was a Japanese solid-fuel rocket designed to launch scientific satellites . It was a member of the Mu family of rockets . The Institute of Space and Astronautical Science (ISAS) began developing the M-V in 1990 at a cost of 15 billion yen . It has three stages and is 30.7 m (101 ft) high, 2.5 m (8 ft 2 in) in diameter , and weighs about 140,000 kg (310,000 lb). It
184-430: A gas , liquid , plasma , or a solid . In powered aircraft without propellers such as jets , the propellant is usually the product of the burning of fuel with atmospheric oxygen so that the resulting propellant product has more mass than the fuel carried on the vehicle. Proposed photon rockets would use the relativistic momentum of photons to create thrust. Even though photons do not have mass, they can still act as
276-410: A nozzle . The exhaust material may be a gas , liquid , plasma , or a solid . In powered aircraft without propellers such as jets , the propellant is usually the product of the burning of fuel with atmospheric oxygen so that the resulting propellant product has more mass than the fuel carried on the vehicle. The propellant or fuel may also simply be a compressed fluid, with the potential energy that
368-460: A plasma which is used as the propellant. They use a nozzle to direct the energized propellant. The nozzle itself may be composed simply of a magnetic field. Low molecular weight gases (e.g. hydrogen, helium, ammonia) are preferred propellants for this kind of system. Electromagnetic thrusters use ions as the propellant, which are accelerated by the Lorentz force or by magnetic fields, either of which
460-483: A broad variety of payloads. Aerosol sprays , in which a liquid is ejected as a spray, include paints, lubricants, degreasers, and protective coatings; deodorants and other personal care products; cooking oils. Some liquid payloads are not sprayed due to lower propellant pressure and/or viscous payload, as with whipped cream and shaving cream or shaving gel. Low-power guns, such as BB guns , paintball guns, and airsoft guns, have solid projectile payloads. Uniquely, in
552-413: A casing, nozzle , grain ( propellant charge ), and igniter . The solid grain mass burns in a predictable fashion to produce exhaust gases, the flow of which is described by Taylor–Culick flow . The nozzle dimensions are calculated to maintain a design chamber pressure, while producing thrust from the exhaust gases. Once ignited, a simple solid rocket motor cannot be shut off, as it contains all
644-400: A compressor, rather than by a chemical reaction. The pressures and energy densities that can be achieved, while insufficient for high-performance rocketry and firearms, are adequate for most applications, in which case compressed fluids offer a simpler, safer, and more practical source of propellant pressure. A compressed fluid propellant may simply be a pressurized gas, or a substance which is
736-482: A control moment. For example, the Titan III C solid boosters injected nitrogen tetroxide for LITV; the tanks can be seen on the sides of the rocket between the main center stage and the boosters. An early Minuteman first stage used a single motor with four gimballed nozzles to provide pitch, yaw, and roll control. A typical, well-designed ammonium perchlorate composite propellant (APCP) first-stage motor may have
828-431: A gas at atmospheric pressure, but stored under pressure as a liquid. In applications in which a large quantity of propellant is used, such as pressure washing and airbrushing , air may be pressurized by a compressor and used immediately. Additionally, a hand pump to compress air can be used for its simplicity in low-tech applications such as atomizers , plant misters and water rockets . The simplest examples of such
920-541: A high-energy (yet unstable) monopropellant and the other acts as a lower-energy stabilizing (and gelling) monopropellant. In typical circumstances, nitroglycerin is dissolved in a nitrocellulose gel and solidified with additives. DB propellants are implemented in applications where minimal smoke is required yet a medium-high I sp of roughly 235 s (2.30 km/s) is required. The addition of metal fuels (such as aluminium ) can increase performance to around 250 s (2.5 km/s), though metal oxide nucleation in
1012-564: A long history as the final boost stage for satellites due to their simplicity, reliability, compactness and reasonably high mass fraction . A spin-stabilized solid rocket motor is sometimes added when extra velocity is required, such as for a mission to a comet or the outer solar system, because a spinner does not require a guidance system (on the newly added stage). Thiokol's extensive family of mostly titanium-cased Star space motors has been widely used, especially on Delta launch vehicles and as spin-stabilized upper stages to launch satellites from
SECTION 10
#17328522306501104-499: A loss in motor performance. Polyurethane-bound aluminium-APCP solid fuel was used in the submarine-launched Polaris missiles . APCP used in the space shuttle Solid Rocket Boosters consisted of ammonium perchlorate (oxidizer, 69.6% by weight), aluminium (fuel, 16%), iron oxide (a catalyst, 0.4%), polybutadiene acrylonitrile (PBAN) polymer (a non-urethane rubber binder that held the mixture together and acted as secondary fuel, 12.04%), and an epoxy curing agent (1.96%). It developed
1196-402: A modest pressure. This pressure is high enough to provide useful propulsion of the payload (e.g. aerosol paint, deodorant, lubricant), but is low enough to be stored in an inexpensive metal can, and to not pose a safety hazard in case the can is ruptured. The mixture of liquid and gaseous propellant inside the can maintains a constant pressure, called the liquid's vapor pressure . As the payload
1288-409: A propellant backwards which creates an opposite force that moves the vehicle forward. Projectiles can use propellants that are expanding gases which provide the motive force to set the projectile in motion. Aerosol cans use propellants which are fluids that are compressed so that when the propellant is allowed to escape by releasing a valve, the energy stored by the compression moves the propellant out of
1380-442: A propellant because they move at relativistic speed, i.e., the speed of light. In this case Newton's third Law of Motion is inadequate to model the physics involved and relativistic physics must be used. In chemical rockets, chemical reactions are used to produce energy which creates movement of a fluid which is used to expel the products of that chemical reaction (and sometimes other substances) as propellants. For example, in
1472-594: A propellant mass fraction of 92.23% while the 14,000-kilogram (31,000 lb) Castor 30 upper stage developed for Orbital Science's Taurus II COTS (Commercial Off The Shelf) (International Space Station resupply) launch vehicle has a 91.3% propellant fraction with 2.9% graphite epoxy motor casing, 2.4% nozzle, igniter and thrust vector actuator, and 3.4% non-motor hardware including such things as payload mount, interstage adapter, cable raceway, instrumentation, etc. Castor 120 and Castor 30 are 2.36 and 2.34 meters (93 and 92 in) in diameter, respectively, and serve as stages on
1564-876: A range of 5,500 metres (3.4 mi). By the end of World War II total production of rocket launchers reached about 10,000. with 12 million rockets of the RS type produced for the Soviet armed forces. In the United States modern castable composite solid rocket motors were invented by the American aerospace engineer Jack Parsons at Caltech in 1942 when he replaced double base propellant with roofing asphalt and potassium perchlorate . This made possible slow-burning rocket motors of adequate size and with sufficient shelf-life for jet-assisted take off applications. Charles Bartley , employed at JPL (Caltech), substituted curable synthetic rubber for
1656-488: A simple hydrogen/oxygen engine, hydrogen is burned (oxidized) to create H 2 O and the energy from the chemical reaction is used to expel the water (steam) to provide thrust. Often in chemical rocket engines, a higher molecular mass substance is included in the fuel to provide more reaction mass. Rocket propellant may be expelled through an expansion nozzle as a cold gas, that is, without energetic mixing and combustion, to provide small changes in velocity to spacecraft by
1748-487: A simple, solid-propellant rocket tube that was filled with gunpowder. One open end allowed the gas to escape and was attached to a long stick that acted as a guidance system for flight direction control. The first rockets with tubes of cast iron were used by the Kingdom of Mysore under Hyder Ali and Tipu Sultan in the 1750s. These rockets had a reach of targets up to a mile and a half away. These were extremely effective in
1840-414: A single-piece nozzle or 304 s (2.98 km/s) with a high-area-ratio telescoping nozzle. Aluminium is used as fuel because it has a reasonable specific energy density, a high volumetric energy density, and is difficult to ignite accidentally. Composite propellants are cast, and retain their shape after the rubber binder, such as Hydroxyl-terminated polybutadiene (HTPB), cross-links (solidifies) with
1932-943: A small charge that is set off when the propellant is exhausted after a time delay. This charge can be used to trigger a camera , or deploy a parachute . Without this charge and delay, the motor may ignite a second stage (black powder only). In mid- and high-power rocketry , commercially made APCP motors are widely used. They can be designed as either single-use or reloadables. These motors are available in impulse ranges from "A" (1.26 Ns– 2.50 Ns) to "O" (20.48 kNs – 40.96 kNs), from several manufacturers. They are manufactured in standardized diameters and varying lengths depending on required impulse. Standard motor diameters are 13, 18, 24, 29, 38, 54, 75, 98, and 150 millimeters. Different propellant formulations are available to produce different thrust profiles, as well as special effects such as colored flames, smoke trails, or large quantities of sparks (produced by adding titanium sponge to
SECTION 20
#17328522306502024-406: A specific impulse of 242 seconds (2.37 km/s) at sea level or 268 seconds (2.63 km/s) in a vacuum. The 2005-2009 Constellation Program was to use a similar PBAN-bound APCP. In 2009, a group succeeded in creating a propellant of water and nanoaluminium ( ALICE ). Typical HEC propellants start with a standard composite propellant mixture (such as APCP) and add a high-energy explosive to
2116-466: A sugar fuel (typically dextrose , sorbitol , or sucrose ) that are cast into shape by gently melting the propellant constituents together and pouring or packing the amorphous colloid into a mold. Candy propellants generate a low-medium specific impulse of roughly 130 s (1.3 km/s) and, thus, are used primarily by amateur and experimental rocketeers. DB propellants are composed of two monopropellant fuel components where one typically acts as
2208-451: A system are squeeze bottles for such liquids as ketchup and shampoo. However, compressed gases are impractical as stored propellants if they do not liquify inside the storage container, because very high pressures are required in order to store any significant quantity of gas, and high-pressure gas cylinders and pressure regulators are expensive and heavy. Liquefied gas propellants are gases at atmospheric pressure, but become liquid at
2300-684: A vacuum specific impulse ( I sp ) as high as 285.6 seconds (2.801 km/s) (Titan IVB SRMU). This compares to 339.3 s (3.327 km/s) for RP1/LOX (RD-180) and 452.3 s (4.436 km/s) for LH 2 /LOX (Block II RS-25 ) bipropellant engines. Upper stage specific impulses are somewhat greater: as much as 303.8 s (2.979 km/s) for APCP (Orbus 6E), 359 s (3.52 km/s) for RP1/LOX (RD-0124) and 465.5 s (4.565 km/s) for LH 2 /LOX (RL10B-2). Propellant fractions are usually somewhat higher for (non-segmented) solid propellant first stages than for upper stages. The 53,000-kilogram (117,000 lb) Castor 120 first stage has
2392-492: A variety of usually ionized propellants, including atomic ions, plasma, electrons, or small droplets or solid particles as propellant. If the acceleration is caused mainly by the Coulomb force (i.e. application of a static electric field in the direction of the acceleration) the device is considered electrostatic. The types of electrostatic drives and their propellants: These are engines that use electromagnetic fields to generate
2484-601: A very primitive form of solid-propellant rocket. Illustrations and descriptions in the 14th century Chinese military treatise Huolongjing by the Ming dynasty military writer and philosopher Jiao Yu confirm that the Chinese in 1232 used proto solid propellant rockets then known as " fire arrows " to drive back the Mongols during the Mongol siege of Kaifeng . Each arrow took a primitive form of
2576-492: Is another pressed propellant that does not find any practical application outside specialized amateur rocketry circles due to its poor performance (as most ZS burns outside the combustion chamber) and fast linear burn rates on the order of 2 m/s. ZS is most often employed as a novelty propellant as the rocket accelerates extremely quickly leaving a spectacular large orange fireball behind it. In general, rocket candy propellants are an oxidizer (typically potassium nitrate) and
2668-523: Is called a reaction engine . Although the term "propellant" is often used in chemical rocket design to describe a combined fuel/propellant, propellants should not be confused with the fuel that is used by an engine to produce the energy that expels the propellant. Even though the byproducts of substances used as fuel are also often used as a reaction mass to create the thrust, such as with a chemical rocket engine, propellant and fuel are two distinct concepts. In electrically powered spacecraft , electricity
2760-552: Is cheap and fairly easy to produce. The fuel grain is typically a mixture of pressed fine powder (into a solid, hard slug), with a burn rate that is highly dependent upon exact composition and operating conditions. The specific impulse of black powder is low, around 80 s (0.78 km/s). The grain is sensitive to fracture and, therefore, catastrophic failure. Black powder does not typically find use in motors above 40 newtons (9.0 pounds-force) thrust. Composed of powdered zinc metal and powdered sulfur (oxidizer), ZS or "micrograin"
2852-440: Is depleted, the propellant vaporizes to fill the internal volume of the can. Liquids are typically 500-1000x denser than their corresponding gases at atmospheric pressure; even at the higher pressure inside the can, only a small fraction of its volume needs to be propellant in order to eject the payload and replace it with vapor. Vaporizing the liquid propellant to gas requires some energy, the enthalpy of vaporization , which cools
M-V - Misplaced Pages Continue
2944-408: Is equal to the volumetric rate times the fuel density ρ {\displaystyle \rho } : Several geometric configurations are often used depending on the application and desired thrust curve : The casing may be constructed from a range of materials. Cardboard is used for small black powder model motors, whereas aluminium is used for larger composite-fuel hobby motors. Steel
3036-436: Is generated by electricity: Nuclear reactions may be used to produce the energy for the expulsion of the propellants. Many types of nuclear reactors have been used/proposed to produce electricity for electrical propulsion as outlined above. Nuclear pulse propulsion uses a series of nuclear explosions to create large amounts of energy to expel the products of the nuclear reaction as the propellant. Nuclear thermal rockets use
3128-408: Is inadequate to model the physics involved and relativistic physics must be used. In chemical rockets, chemical reactions are used to produce energy which creates movement of a fluid which is used to expel the products of that chemical reaction (and sometimes other substances) as propellants. For example, in a simple hydrogen/oxygen engine, hydrogen is burned (oxidized) to create H 2 O and
3220-428: Is non-polluting: acid-free, solid particulates-free, and lead-free. It is also smokeless and has only a faint shock diamond pattern that is visible in the otherwise transparent exhaust. Without the bright flame and dense smoke trail produced by the burning of aluminized propellants, these smokeless propellants all but eliminate the risk of giving away the positions from which the missiles are fired. The new CL-20 propellant
3312-411: Is shock-insensitive (hazard class 1.3) as opposed to current HMX smokeless propellants which are highly detonable (hazard class 1.1). CL-20 is considered a major breakthrough in solid rocket propellant technology but has yet to see widespread use because costs remain high. Electric solid propellants (ESPs) are a family of high performance plastisol solid propellants that can be ignited and throttled by
3404-417: Is simply heated using resistive heating as it is expelled to create more thrust. In chemical rockets and aircraft, fuels are used to produce an energetic gas that can be directed through a nozzle , thereby producing thrust. In rockets, the burning of rocket fuel produces an exhaust, and the exhausted material is usually expelled as a propellant under pressure through a nozzle . The exhaust material may be
3496-431: Is stored in the compressed fluid used to expel the fluid as the propellant. The energy stored in the fluid was added to the system when the fluid was compressed, such as compressed air . The energy applied to the pump or thermal system that is used to compress the air is stored until it is released by allowing the propellant to escape. Compressed fluid may also be used only as energy storage along with some other substance as
3588-434: Is to achieve mid-course exo-atmospheric ABM capability from missiles small enough to fit in existing ship-based below-deck vertical launch tubes and air-mobile truck-mounted launch tubes. CL-20 propellant compliant with Congress' 2004 insensitive munitions (IM) law has been demonstrated and may, as its cost comes down, be suitable for use in commercial launch vehicles, with a very significant increase in performance compared with
3680-409: Is used to accelerate the propellant. An electrostatic force may be used to expel positive ions, or the Lorentz force may be used to expel negative ions and electrons as the propellant. Electrothermal engines use the electromagnetic force to heat low molecular weight gases (e.g. hydrogen, helium, ammonia) into a plasma and expel the plasma as propellant. In the case of a resistojet rocket engine,
3772-400: Is used to compress the air is stored until it is released by allowing the propellant to escape. Compressed fluid may also be used only as energy storage along with some other substance as the propellant, such as with a water rocket , where the energy stored in the compressed air is the fuel and the water is the propellant. In electrically powered spacecraft , electricity is used to accelerate
M-V - Misplaced Pages Continue
3864-645: The Battle of Khalkhin Gol . In June 1938, the RNII began developing a multiple rocket launcher based on the RS-132 rocket. In August 1939, the completed product was the BM-13 / Katyusha rocket launcher . Towards the end of 1938 the first significant large scale testing of the rocket launchers took place, 233 rockets of various types were used. A salvo of rockets could completely straddle a target at
3956-579: The H-IIA solid rocket booster as the first stage and through shorter launch preparation time. Epsilon launches are intended to cost much less than the US$ 70 million launch cost of a M-V. The first launch, of a small scientific satellite SPRINT-A ( Hisaki ), took place in September 2013. The initial launches will be of a two-stage version, of Epsilon, with up to a 500 kilogram LEO payload capability. Solid fuel rockets are
4048-586: The LGM-118 Peacekeeper ICBM. Solid-fuel rocket A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants ( fuel / oxidizer ). The earliest rockets were solid-fuel rockets powered by gunpowder . The inception of gunpowder rockets in warfare can be credited to the ancient Chinese, and in the 13th century, the Mongols played a pivotal role in facilitating their westward adoption. All rockets used some form of solid or powdered propellant until
4140-637: The Reactive Scientific Research Institute (RNII) with the development of the RS-82 and RS-132 rockets , including designing several variations for ground-to-air, ground-to-ground, air-to-ground and air-to-air combat. The earliest known use by the Soviet Air Force of aircraft-launched unguided anti-aircraft rockets in combat against heavier-than-air aircraft took place in August 1939 , during
4232-746: The Second Anglo-Mysore War that ended in a humiliating defeat for the British East India Company . Word of the success of the Mysore rockets against the British triggered research in England, France, Ireland and elsewhere. When the British finally conquered the fort of Srirangapatana in 1799, hundreds of rockets were shipped off to the Royal Arsenal near London to be reverse-engineered. This led to
4324-500: The fuel and oxidizer mass. Grain geometry and chemistry are then chosen to satisfy the required motor characteristics. The following are chosen or solved simultaneously. The results are exact dimensions for grain, nozzle, and case geometries: The grain may or may not be bonded to the casing. Case-bonded motors are more difficult to design, since the deformation of the case and the grain under flight must be compatible. Common modes of failure in solid rocket motors include fracture of
4416-570: The 2010s include the European Ariane 5 , US Atlas V and Space Shuttle , and Japan's H-II . The largest solid rocket motors ever built were Aerojet's three 6.60-meter (260 in) monolithic solid motors cast in Florida. Motors 260 SL-1 and SL-2 were 6.63 meters (261 in) in diameter, 24.59 meters (80 ft 8 in) long, weighed 842,900 kilograms (1,858,300 lb), and had a maximum thrust of 16 MN (3,500,000 lbf). Burn duration
4508-1119: The 20th century, when liquid-propellant rockets offered more efficient and controllable alternatives. Because of their simplicity and reliability, solid rockets are still used today in military armaments worldwide, model rockets , solid rocket boosters and on larger applications. Since solid-fuel rockets can remain in storage for an extended period without much propellant degradation, and since they almost always launch reliably, they have been frequently used in military applications such as missiles . The lower performance of solid propellants (as compared to liquids) does not favor their use as primary propulsion in modern medium-to-large launch vehicles customarily used for commercial satellites and major space probes. Solids are, however, frequently used as strap-on boosters to increase payload capacity or as spin-stabilized add-on upper stages when higher-than-normal velocities are required. Solid rockets are used as light launch vehicles for low Earth orbit (LEO) payloads under 2 tons or escape payloads up to 500 kilograms (1,100 lb). A simple solid rocket motor consists of
4600-655: The Athena IC and IIC commercial launch vehicles. A four-stage Athena II using Castor 120s as both first and second stages became the first commercially developed launch vehicle to launch a lunar probe ( Lunar Prospector ) in 1998. Solid rockets can provide high thrust for relatively low cost. For this reason, solids have been used as initial stages in rockets (for example the Space Shuttle ), while reserving high specific impulse engines, especially less massive hydrogen-fueled engines, for higher stages. In addition, solid rockets have
4692-493: The aid of a curative additive. Because of its high performance, moderate ease of manufacturing, and moderate cost, APCP finds widespread use in space, military, and amateur rockets, whereas cheaper and less efficient ANCP finds use in amateur rocketry and gas generators . Ammonium dinitramide , NH 4 N(NO 2 ) 2 , is being considered as a 1-to-1 chlorine-free substitute for ammonium perchlorate in composite propellants. Unlike ammonium nitrate, ADN can be substituted for AP without
SECTION 50
#17328522306504784-459: The application of electric current. Unlike conventional rocket motor propellants that are difficult to control and extinguish, ESPs can be ignited reliably at precise intervals and durations. It requires no moving parts and the propellant is insensitive to flames or electrical sparks. Solid propellant rocket motors can be bought for use in model rocketry ; they are normally small cylinders of black powder fuel with an integral nozzle and optionally
4876-564: The burning of the fuel and, as a consequence, thrust vs time profile. There are three types of burns that can be achieved with different grains. There are four different types of solid fuel/propellant compositions: In rockets, three main liquid bipropellant combinations are used: cryogenic oxygen and hydrogen, cryogenic oxygen and a hydrocarbon, and storable propellants. Propellant combinations used for liquid propellant rockets include: Common monopropellant used for liquid rocket engines include: Electrically powered reactive engines use
4968-425: The can and that propellant forces the aerosol payload out along with the propellant. Compressed fluid may also be used as a simple vehicle propellant, with the potential energy that is stored in the compressed fluid used to expel the fluid as the propellant. The energy stored in the fluid was added to the system when the fluid was compressed, such as compressed air . The energy applied to the pump or thermal system that
5060-460: The cargo bay of the Space Shuttle. Star motors have propellant fractions as high as 94.6% but add-on structures and equipment reduce the operating mass fraction by 2% or more. Higher performing solid rocket propellants are used in large strategic missiles (as opposed to commercial launch vehicles). HMX , C 4 H 8 N 4 (NO 2 ) 4 , a nitramine with greater energy than ammonium perchlorate,
5152-452: The casing is often implemented, which ablates to prolong the life of the motor casing. A convergent-divergent design accelerates the exhaust gas out of the nozzle to produce thrust. The nozzle must be constructed from a material that can withstand the heat of the combustion gas flow. Often, heat-resistant carbon-based materials are used, such as amorphous graphite or reinforced carbon–carbon . Some designs include directional control of
5244-403: The compressed propellant is simply heated using resistive heating as it is expelled to create more thrust. In chemical rockets and aircraft, fuels are used to produce an energetic gas that can be directed through a nozzle , thereby producing thrust. In rockets, the burning of rocket fuel produces an exhaust, and the exhausted material is usually expelled as a propellant under pressure through
5336-454: The currently favored APCP solid propellants. With a specific impulse of 309 s already demonstrated by Peacekeeper's second stage using HMX propellant, the higher energy of CL-20 propellant can be expected to increase specific impulse to around 320 s in similar ICBM or launch vehicle upper stage applications, without the explosive hazard of HMX. An attractive attribute for military use is the ability for solid rocket propellant to remain loaded in
5428-404: The design of choice for military applications as they can remain in storage for long periods, and then reliably launch at short notice. Lawmakers made national security arguments for keeping Japan's solid-fuel rocket technology alive after ISAS was merged into JAXA , which also has the H-IIA liquid-fuelled rocket, in 2003. The ISAS director of external affairs, Yasunori Matogawa, said, "It seems
5520-652: The disadvantage of being flammable . Nitrous oxide and carbon dioxide are also used as propellants to deliver foodstuffs (for example, whipped cream and cooking spray ). Medicinal aerosols such as asthma inhalers use hydrofluoroalkanes (HFA): either HFA 134a (1,1,1,2,-tetrafluoroethane) or HFA 227 (1,1,1,2,3,3,3-heptafluoropropane) or combinations of the two. More recently, liquid hydrofluoroolefin (HFO) propellants have become more widely adopted in aerosol systems due to their relatively low vapor pressure, low global warming potential (GWP), and nonflammability. The practicality of liquified gas propellants allows for
5612-399: The energy from the chemical reaction is used to expel the water (steam) to provide thrust. Often in chemical rocket engines, a higher molecular mass substance is included in the fuel to provide more reaction mass. Rocket propellant may be expelled through an expansion nozzle as a cold gas, that is, without energetic mixing and combustion, to provide small changes in velocity to spacecraft by
SECTION 60
#17328522306505704-611: The exhaust can turn the smoke opaque. A powdered oxidizer and powdered metal fuel are intimately mixed and immobilized with a rubbery binder (that also acts as a fuel). Composite propellants are often either ammonium-nitrate -based (ANCP) or ammonium-perchlorate -based (APCP). Ammonium nitrate composite propellant often uses magnesium and/or aluminium as fuel and delivers medium performance (I sp of about 210 s (2.1 km/s)) whereas ammonium perchlorate composite propellant often uses aluminium fuel and delivers high performance: vacuum I sp up to 296 s (2.90 km/s) with
5796-531: The exhaust. This can be accomplished by gimballing the nozzle, as in the Space Shuttle SRBs, by the use of jet vanes in the exhaust as in the V-2 rocket, or by liquid injection thrust vectoring (LITV). LITV consists of injecting a liquid into the exhaust stream after the nozzle throat. The liquid then vaporizes, and in most cases chemically reacts, adding mass flow to one side of the exhaust stream and thus providing
5888-405: The fifth M-V Hayabusa mission was that the reentry and landing of its return capsule demonstrated "that Japan's ballistic missile capability is credible". At a technical level the M-V design could be weaponised quickly (as an Intercontinental ballistic missile , since only payload and guidance have to be changed) although this would be politically unlikely. The M-V is comparable in performance to
5980-554: The first industrial manufacture of military rockets with the Congreve rocket in 1804. In 1921 the Soviet research and development laboratory Gas Dynamics Laboratory began developing solid-propellant rockets, which resulted in the first launch in 1928, that flew for approximately 1,300 metres. These rockets were used in 1931 for the world's first successful use of rockets to assist take-off of aircraft . The research continued from 1933 by
6072-445: The functional definition of double base propellants. One of the most active areas of solid propellant research is the development of high-energy, minimum-signature propellant using C 6 H 6 N 6 (NO 2 ) 6 CL-20 nitroamine ( China Lake compound #20), which has 14% higher energy per mass and 20% higher energy density than HMX. The new propellant has been successfully developed and tested in tactical rocket motors. The propellant
6164-470: The gooey asphalt, creating a flexible but geometrically stable load-bearing propellant grain that bonded securely to the motor casing. This made possible much larger solid rocket motors. Atlantic Research Corporation significantly boosted composite propellant I sp in 1954 by increasing the amount of powdered aluminium in the propellant to as much as 20%. Solid-propellant rocket technology got its largest boost in technical innovation, size and capability with
6256-440: The grain, failure of case bonding, and air pockets in the grain. All of these produce an instantaneous increase in burn surface area and a corresponding increase in exhaust gas production rate and pressure, which may rupture the casing. Another failure mode is casing seal failure. Seals are required in casings that have to be opened to load the grain. Once a seal fails, hot gas will erode the escape path and result in failure. This
6348-404: The hard-line national security proponents in parliament are increasing their influence, and they aren't getting much criticism... I think we’re moving into a very dangerous period. When you consider the current environment and the threat from North Korea , it's scary". Toshiyuki Shikata, a Tokyo Metropolitan Government adviser and former lieutenant general, claimed that part of the rationale for
6440-461: The heat of a nuclear reaction to heat a propellant. Usually the propellant is hydrogen because the force is a function of the energy irrespective of the mass of the propellant, so the lightest propellant (hydrogen) produces the greatest specific impulse . A photonic reactive engine uses photons as the propellant and their discrete relativistic energy to produce thrust. Compressed fluid or compressed gas propellants are pressurized physically, by
6532-658: The ingredients necessary for combustion within the chamber in which they are burned. More advanced solid rocket motors can be throttled , or extinguished and re-ignited, by control of the nozzle geometry or through the use of vent ports. Further, pulsed rocket motors that burn in segments, and that can be ignited upon command are available. Modern designs may also include a steerable nozzle for guidance, avionics , recovery hardware ( parachutes ), self-destruct mechanisms, APUs , controllable tactical motors, controllable divert and attitude control motors, and thermal management materials. The medieval Song dynasty Chinese invented
6624-399: The mix). Almost all sounding rockets use solid motors. Due to reliability, ease of storage and handling, solid rockets are used on missiles and ICBMs. Solid rockets are suitable for launching small payloads to orbital velocities, especially if three or more stages are used. Many of these are based on repurposed ICBMs. Propellant Vehicles can use propellants to move by ejecting
6716-560: The mix. This extra component usually is in the form of small crystals of RDX or HMX , both of which have higher energy than ammonium perchlorate. Despite a modest increase in specific impulse, implementation is limited due to the increased hazards of the high-explosive additives. Composite modified double base propellants start with a nitrocellulose/nitroglycerin double base propellant as a binder and add solids (typically ammonium perchlorate (AP) and powdered aluminium ) normally used in composite propellants. The ammonium perchlorate makes up
6808-402: The newly synthesized bishomocubane based compounds are under consideration in the research stage as both solid and liquid propellants of the future. Solid fuel/propellants are used in forms called grains . A grain is any individual particle of fuel/propellant regardless of the size or shape. The shape and size of a grain determines the burn time, amount of gas, and rate of produced energy from
6900-420: The next 50 years. By the later 1980s and continuing to 2020, these government-developed highly-capable solid rocket technologies have been applied to orbital spaceflight by many government-directed programs , most often as booster rockets to add extra thrust during the early ascent of their primarily liquid rocket launch vehicles . Some designs have had solid rocket upper stages as well. Examples flying in
6992-557: The oxygen deficit introduced by using nitrocellulose , improving the overall specific impulse. The aluminium improves specific impulse as well as combustion stability. High performing propellants such as NEPE-75 used to fuel the Trident II D-5 SLBM replace most of the AP with polyethylene glycol -bound HMX , further increasing specific impulse. The mixing of composite and double base propellant ingredients has become so common as to blur
7084-463: The propellant surface area exposed to the combustion gases. Since the propellant volume is equal to the cross sectional area A s {\displaystyle A_{s}} times the fuel length, the volumetric propellant consumption rate is the cross section area times the linear burn rate b ˙ {\displaystyle {\dot {b}}} , and the instantaneous mass flow rate of combustion gases generated
7176-522: The propellant). Chlorofluorocarbons (CFCs) were once often used as propellants, but since the Montreal Protocol came into force in 1989, they have been replaced in nearly every country due to the negative effects CFCs have on Earth's ozone layer . The most common replacements of CFCs are mixtures of volatile hydrocarbons , typically propane , n- butane and isobutane . Dimethyl ether (DME) and methyl ethyl ether are also used. All these have
7268-414: The propellant, such as with a water rocket , where the energy stored in the compressed air is the fuel and the water is the propellant. Proposed photon rockets would use the relativistic momentum of photons to create thrust. Even though photons do not have mass, they can still act as a propellant because they move at relativistic speed, i.e., the speed of light. In this case Newton's third Law of Motion
7360-413: The propellant. An electrostatic force may be used to expel positive ions, or the Lorentz force may be used to expel negative ions and electrons as the propellant. Electrothermal engines use the electromagnetic force to heat low molecular weight gases (e.g. hydrogen, helium, ammonia) into a plasma and expel the plasma as propellant. In the case of a resistojet rocket engine, the compressed propellant
7452-417: The retired Peacekeeper ICBMs). The Naval Air Weapons Station at China Lake, California, developed a new compound, C 6 H 6 N 6 (NO 2 ) 6 , called simply CL-20 (China Lake compound 20). Compared to HMX, CL-20 has 14% more energy per mass, 20% more energy per volume, and a higher oxygen-to-fuel ratio. One of the motivations for development of these very high energy density military solid propellants
7544-403: The rocket for long durations and then be reliably launched at a moment's notice. Black powder (gunpowder) is composed of charcoal (fuel), potassium nitrate (oxidizer), and sulfur (fuel and catalyst). It is one of the oldest pyrotechnic compositions with application to rocketry. In modern times, black powder finds use in low-power model rockets (such as Estes and Quest rockets), as it
7636-413: The system. This is usually insignificant, although it can sometimes be an unwanted effect of heavy usage (as the system cools, the vapor pressure of the propellant drops). However, in the case of a freeze spray , this cooling contributes to the desired effect (although freeze sprays may also contain other components, such as chloroethane , with a lower vapor pressure but higher enthalpy of vaporization than
7728-413: The use of cold gas thrusters , usually as maneuvering thrusters. To attain a useful density for storage, most propellants are stored as either a solid or a liquid. A rocket propellant is a mass that is expelled from a vehicle, such as a rocket, in such a way as to create a thrust in accordance with Newton's third law of motion , and "propel" the vehicle forward. The engine that expels the propellant
7820-551: The use of cold gas thrusters , usually as maneuvering thrusters. To attain a useful density for storage, most propellants are stored as either a solid or a liquid. Propellants may be energized by chemical reactions to expel solid, liquid or gas. Electrical energy may be used to expel gases, plasmas, ions, solids or liquids. Photons may be used to provide thrust via relativistic momentum. Propellants that explode in operation are of little practical use currently, although there have been experiments with Pulse Detonation Engines . Also
7912-610: The various mid-20th century government initiatives to develop increasingly capable military missiles. After initial designs of ballistic missile military technology designed with liquid-propellant rockets in the 1940s and 1950s, both the Soviet Union and the United States embarked on major initiatives to develop solid-propellant local , regional , and intercontinental ballistic missiles, including solid-propellant missiles that could be launched from air or sea . Many other governments also developed these military technologies over
8004-679: Was capable of launching a satellite weighing 1,800 kg (4,000 lb) into an orbit as high as 250 km (160 mi). The first M-V rocket launched the HALCA radio astronomy satellite in 1997, and the second the Nozomi Mars explorer in July 1998. The third rocket attempted to launch the Astro-E X-ray satellite on 10 February 2000 but failed. ISAS recovered from this setback and launched Hayabusa to 25143 Itokawa in 2003. The following M-V launch
8096-478: Was the cause of the Space Shuttle Challenger disaster . Solid rocket fuel deflagrates from the surface of exposed propellant in the combustion chamber. In this fashion, the geometry of the propellant inside the rocket motor plays an important role in the overall motor performance. As the surface of the propellant burns, the shape evolves (a subject of study in internal ballistics), most often changing
8188-571: Was the scientific Astro-E2 satellite, a replacement for Astro-E, which took place on 10 July 2005. The final launch was that of the Hinode (SOLAR-B) spacecraft, along with the SSSat microsat and a nanosatellite , HIT-SAT , on 22 September 2006. A follow on to the M-V, called the Epsilon Rocket , features a lower 1.2 tonne LEO payload capability. The development aim is to reduce costs, primarily by using
8280-423: Was two minutes. The nozzle throat was large enough to walk through standing up. The motor was capable of serving as a 1-to-1 replacement for the 8-engine Saturn I liquid-propellant first stage but was never used as such. Motor 260 SL-3 was of similar length and weight but had a maximum thrust of 24 MN (5,400,000 lbf) and a shorter duration. Design begins with the total impulse required, which determines
8372-407: Was used for the space shuttle boosters . Filament-wound graphite epoxy casings are used for high-performance motors. The casing must be designed to withstand the pressure and resulting stresses of the rocket motor, possibly at elevated temperature. For design, the casing is considered a pressure vessel . To protect the casing from corrosive hot gases, a sacrificial thermal liner on the inside of
8464-642: Was used in the propellant of the Peacekeeper ICBM and is the main ingredient in NEPE-75 propellant used in the Trident II D-5 Fleet Ballistic Missile. It is because of explosive hazard that the higher energy military solid propellants containing HMX are not used in commercial launch vehicles except when the LV is an adapted ballistic missile already containing HMX propellant (Minotaur IV and V based on
#649350