Misplaced Pages

#808191

100-581: LCC has conducted launches since the unmanned Apollo 4 (Apollo-Saturn 501) launch on November 9, 1967. LCC's first launch with a human crew was Apollo 8 on December 21, 1968. NASA's Space Shuttle program also used LCC. NASA has renovated the center for Space Launch System (SLS) missions, which began in 2022 with Artemis 1 . In February 2022, the center was renamed after former launch director Rocco A. Petrone . Launch operations are supervised and controlled from several control rooms known as firing rooms. The controllers are in control of pre-launch checks,

200-464: A rocket if it is unguided. Anti-tank and anti-aircraft missiles use rocket engines to engage targets at high speed at a range of several miles, while intercontinental ballistic missiles can be used to deliver multiple nuclear warheads from thousands of miles, and anti-ballistic missiles try to stop them. Rockets have also been tested for reconnaissance , such as the Ping-Pong rocket , which

300-420: A multi-stage rocket , and also pioneered the concept of a rocket launch pad (a rocket standing upright against a tall building before launch having been slowly rolled into place) and the rocket-launch countdown clock. The Guardian film critic Stephen Armstrong states Lang "created the rocket industry". Lang was inspired by the 1923 book The Rocket into Interplanetary Space by Hermann Oberth, who became

400-565: A nozzle . They may also have one or more rocket engines , directional stabilization device(s) (such as fins , vernier engines or engine gimbals for thrust vectoring , gyroscopes ) and a structure (typically monocoque ) to hold these components together. Rockets intended for high speed atmospheric use also have an aerodynamic fairing such as a nose cone , which usually holds the payload. As well as these components, rockets can have any number of other components, such as wings ( rocketplanes ), parachutes , wheels ( rocket cars ), even, in

500-399: A rocket engine in the form of a fluid jet to produce thrust . For chemical rockets often the propellants are a fuel such as liquid hydrogen or kerosene burned with an oxidizer such as liquid oxygen or nitric acid to produce large volumes of very hot gas. The oxidiser is either kept separate and mixed in the combustion chamber, or comes premixed, as with solid rockets. Sometimes

600-475: A vehicle may usefully employ for propulsion, such as in space. In these circumstances, it is necessary to carry all the propellant to be used. However, they are also useful in other situations: Some military weapons use rockets to propel warheads to their targets. A rocket and its payload together are generally referred to as a missile when the weapon has a guidance system (not all missiles use rocket engines, some use other engines such as jets ) or as

700-773: A body of theory that has provided the foundation for subsequent spaceflight development. The British Royal Flying Corps designed a guided rocket during World War I . Archibald Low stated "...in 1917 the Experimental Works designed an electrically steered rocket… Rocket experiments were conducted under my own patents with the help of Cdr. Brock ." The patent "Improvements in Rockets" was raised in July 1918 but not published until February 1923 for security reasons. Firing and guidance controls could be either wire or wireless. The propulsion and guidance rocket eflux emerged from

800-415: A cardboard tube filled with black powder , but to make an efficient, accurate rocket or missile involves overcoming a number of difficult problems. The main difficulties include cooling the combustion chamber, pumping the fuel (in the case of a liquid fuel), and controlling and correcting the direction of motion. Rockets consist of a propellant , a place to put propellant (such as a propellant tank ), and

900-432: A chemical reaction is initiated between the fuel and the oxidizer in the combustion chamber, and the resultant hot gases accelerate out of a rocket engine nozzle (or nozzles ) at the rearward-facing end of the rocket. The acceleration of these gases through the engine exerts force ("thrust") on the combustion chamber and nozzle, propelling the vehicle (according to Newton's Third Law ). This actually happens because

1000-499: A decomposing monopropellant ) that emit a hot exhaust gas . A rocket engine can use gas propellants, solid propellant , liquid propellant , or a hybrid mixture of both solid and liquid . Some rockets use heat or pressure that is supplied from a source other than the chemical reaction of propellant(s), such as steam rockets , solar thermal rockets , nuclear thermal rocket engines or simple pressurized rockets such as water rocket or cold gas thrusters . With combustive propellants

1100-530: A failed launch. A successful escape of a crewed capsule occurred when Soyuz T-10 , on a mission to the Salyut 7 space station , exploded on the pad. Solid rocket propelled ejection seats are used in many military aircraft to propel crew away to safety from a vehicle when flight control is lost. A model rocket is a small rocket designed to reach low altitudes (e.g., 100–500 m (330–1,640 ft) for 30 g (1.1 oz) model) and be recovered by

SECTION 10

#1732771806809

1200-435: A fixed location on the ground, but would also be possible from an aircraft or ship. Rocket launch technologies include the entire set of systems needed to successfully launch a vehicle, not just the vehicle itself, but also the firing control systems , mission control center , launch pad , ground stations , and tracking stations needed for a successful launch or recovery or both. These are often collectively referred to as

1300-449: A given propellant chemistry is proportional to the energy released per unit of propellant mass (specific energy). In chemical rockets, unburned fuel or oxidizer represents the loss of chemical potential energy , which reduces the specific energy . However, most rockets run fuel-rich mixtures, which result in lower theoretical exhaust velocities. However, fuel-rich mixtures also have lower molecular weight exhaust species. The nozzle of

1400-408: A good choice whenever large amounts of thrust are needed and the cost is an issue. The Space Shuttle and many other orbital launch vehicles use solid-fueled rockets in their boost stages ( solid rocket boosters ) for this reason. Solid fuel rockets have lower specific impulse , a measure of propellant efficiency, than liquid fuel rockets. As a result, the overall performance of solid upper stages

1500-561: A high pressure combustion chamber . These nozzles turn the hot gas from the combustion chamber into a cooler, hypersonic , highly directed jet of gas, more than doubling the thrust and raising the engine efficiency from 2% to 64%. His use of liquid propellants instead of gunpowder greatly lowered the weight and increased the effectiveness of rockets. In 1921, the Soviet research and development laboratory Gas Dynamics Laboratory began developing solid-propellant rockets , which resulted in

1600-439: A hybrid motor, the mixing happens at the melting or evaporating surface of the fuel. The mixing is not a well-controlled process and generally, quite a lot of propellant is left unburned, which limits the efficiency of the motor. The combustion rate of the fuel is largely determined by the oxidizer flux and exposed fuel surface area. This combustion rate is not usually sufficient for high power operations such as boost stages unless

1700-411: A manual hold if necessary. After T-31 seconds only an automatic cutoff is available. The automatic cutoff recycles the countdown clock to T-20 minutes. Usually this will extend the launch time beyond the launch window causing a scrub and a 24-hour turnaround. Rocket launch A rocket (from Italian : rocchetto , lit.   ''bobbin/spool'', and so named for its shape)

1800-543: A pointed tip traveling at high speeds, model rocketry historically has proven to be a very safe hobby and has been credited as a significant source of inspiration for children who eventually become scientists and engineers . Hobbyists build and fly a wide variety of model rockets. Many companies produce model rocket kits and parts but due to their inherent simplicity some hobbyists have been known to make rockets out of almost anything. Rockets are also used in some types of consumer and professional fireworks . A water rocket

1900-571: A polymer binding agent, with flakes or powders of energetic fuel compounds (examples: RDX , HMX , aluminium, beryllium). Plasticizers, stabilizers, and/or burn rate modifiers (iron oxide, copper oxide) can also be added. Single-, double-, or triple-bases (depending on the number of primary ingredients) are homogeneous mixtures of one to three primary ingredients. These primary ingredients must include fuel and oxidizer and often also include binders and plasticizers. All components are macroscopically indistinguishable and often blended as liquids and cured in

2000-698: A polymeric binder) the fuel is charcoal, the oxidizer is potassium nitrate, and sulphur serves as a reaction catalyst while also being consumed to form a variety of reaction products such as potassium sulfide . The newest nitramine solid propellants based on CL-20 (HNIW) can match the performance of NTO / UDMH storable liquid propellants, but cannot be throttled or restarted. Solid propellant rockets are much easier to store and handle than liquid propellant rockets. High propellant density makes for compact size as well. These features plus simplicity and low cost make solid propellant rockets ideal for military and space applications. Their simplicity also makes solid rockets

2100-441: A precision maneuverable bus used to fine tune the trajectory of the re-entry vehicles. Liquid-fueled rockets have higher specific impulse than solid rockets and are capable of being throttled, shut down, and restarted. Only the combustion chamber of a liquid-fueled rocket needs to withstand high combustion pressures and temperatures. Cooling can be done regeneratively with the liquid propellant. On vehicles employing turbopumps ,

SECTION 20

#1732771806809

2200-415: A programmed thrust schedule can be created by adjusting the interior propellant geometry. Solid rockets can be vented to extinguish combustion or reverse thrust as a means of controlling range or accommodating stage separation. Casting large amounts of propellant requires consistency and repeatability to avoid cracks and voids in the completed motor. The blending and casting take place under computer control in

2300-614: A rail at extremely high speed. The world record for this is Mach 8.5. Larger rockets are normally launched from a launch pad that provides stable support until a few seconds after ignition. Due to their high exhaust velocity—2,500 to 4,500 m/s (9,000 to 16,200 km/h; 5,600 to 10,100 mph)—rockets are particularly useful when very high speeds are required, such as orbital speed at approximately 7,800 m/s (28,000 km/h; 17,000 mph). Spacecraft delivered into orbital trajectories become artificial satellites , which are used for many commercial purposes. Indeed, rockets remain

2400-693: A reference to 1264, recording that the "ground-rat", a type of firework , had frightened the Empress-Mother Gongsheng at a feast held in her honor by her son the Emperor Lizong . Subsequently, rockets are included in the military treatise Huolongjing , also known as the Fire Drake Manual, written by the Chinese artillery officer Jiao Yu in the mid-14th century. This text mentions the first known multistage rocket ,

2500-504: A sense, a person ( rocket belt ). Vehicles frequently possess navigation systems and guidance systems that typically use satellite navigation and inertial navigation systems . Rocket engines employ the principle of jet propulsion . The rocket engines powering rockets come in a great variety of different types; a comprehensive list can be found in the main article, Rocket engine . Most current rockets are chemically powered rockets (usually internal combustion engines , but some employ

2600-445: A single batch. Ingredients can often have multiple roles. For example, RDX is both a fuel and oxidizer while nitrocellulose is a fuel, oxidizer, and structural polymer. Further complicating categorization, there are many propellants that contain elements of double-base and composite propellants, which often contain some amount of energetic additives homogeneously mixed into the binder. In the case of gunpowder (a pressed composite without

2700-454: A solid combination of fuel with oxidizer ( solid fuel ), or solid fuel with liquid or gaseous oxidizer ( hybrid propellant system ). Chemical rockets store a large amount of energy in an easily released form, and can be very dangerous. However, careful design, testing, construction and use minimizes risks. In China, gunpowder -powered rockets evolved in medieval China under the Song dynasty by

2800-424: A solid fuel and a liquid or NEMA oxidizer. The fluid oxidizer can make it possible to throttle and restart the motor just like a liquid-fueled rocket. Hybrid rockets can also be environmentally safer than solid rockets since some high-performance solid-phase oxidizers contain chlorine (specifically composites with ammonium perchlorate), versus the more benign liquid oxygen or nitrous oxide often used in hybrids. This

2900-434: A vacuum, and the propellant blend is spread thin and scanned to assure no large gas bubbles are introduced into the motor. Solid fuel rockets are intolerant to cracks and voids and require post-processing such as X-ray scans to identify faults. The combustion process is dependent on the surface area of the fuel. Voids and cracks represent local increases in burning surface area, increasing the local temperature, which increases

3000-724: A variety of means. According to the United States National Association of Rocketry (nar) Safety Code, model rockets are constructed of paper, wood, plastic and other lightweight materials. The code also provides guidelines for motor use, launch site selection, launch methods, launcher placement, recovery system design and deployment and more. Since the early 1960s, a copy of the Model Rocket Safety Code has been provided with most model rocket kits and motors. Despite its inherent association with extremely flammable substances and objects with

3100-407: Is a vehicle that uses jet propulsion to accelerate without using any surrounding air . A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely from propellant carried within the vehicle; therefore a rocket can fly in the vacuum of space. Rockets work more efficiently in a vacuum and incur a loss of thrust due to the opposing pressure of

Launch Control Center - Misplaced Pages Continue

3200-706: Is a contractor member of the Space Shuttle Team. The LPS Coordinator monitors and oversees the LPS System; specifically, the desired launch rate, Space Shuttle stacking (assembly), and all safety requirements. This is made possible by the Launch Processing System , or LPS — a highly automated, computer-controlled system that oversees the entire checkout and launch process. The Superintendent of Range Operations ensures that all tracking and communications systems are ready to support

3300-416: Is a type of model rocket using water as its reaction mass. The pressure vessel (the engine of the rocket) is usually a used plastic soft drink bottle. The water is forced out by a pressurized gas, typically compressed air. It is an example of Newton's third law of motion. The scale of amateur rocketry can range from a small rocket launched in one's own backyard to a rocket that reached space. Amateur rocketry

3400-412: Is also possible to fit a longer nozzle without suffering from flow separation . Most chemical propellants release energy through redox chemistry , more specifically combustion . As such, both an oxidizing agent and a reducing agent (fuel) must be present in the mixture. Decomposition, such as that of highly unstable peroxide bonds in monopropellant rockets, can also be the source of energy. In

3500-432: Is described by the rocket equation . Exhaust velocity is dependent on the propellant and engine used and closely related to specific impulse , the total energy delivered to the rocket vehicle per unit of propellant mass consumed. Mass ratio can also be affected by the choice of a given propellant. Rocket stages that fly through the atmosphere usually use lower performing, high molecular mass, high-density propellants due to

3600-491: Is large enough that real rocket engines improve their actual exhaust velocity by running rich mixtures with somewhat lower theoretical exhaust velocities. The effect of exhaust molecular weight on nozzle efficiency is most important for nozzles operating near sea level. High expansion rockets operating in a vacuum see a much smaller effect, and so are run less rich. LOX/hydrocarbon rockets are run slightly rich (O/F mass ratio of 3 rather than stoichiometric of 3.4 to 4) because

3700-406: Is less necessary, a pressurised fluid is used as propellant that simply escapes the spacecraft through a propelling nozzle. The first liquid-fuel rocket , constructed by Robert H. Goddard , differed significantly from modern rockets. The rocket engine was at the top and the fuel tank at the bottom of the rocket, based on Goddard's belief that the rocket would achieve stability by "hanging" from

3800-427: Is less than liquid stages even though the solid mass ratios are usually in the .91 to .93 range, as good as or better than most liquid propellant upper stages. The high mass ratios possible with these unsegmented solid upper stages is a result of high propellant density and very high strength-to-weight ratio filament-wound motor casings. A drawback to solid rockets is that they cannot be throttled in real time, although

3900-558: Is only true for specific hybrid systems. There have been hybrids which have used chlorine or fluorine compounds as oxidizers and hazardous materials such as beryllium compounds mixed into the solid fuel grain. Because just one constituent is a fluid, hybrids can be simpler than liquid rockets depending motive force used to transport the fluid into the combustion chamber. Fewer fluids typically mean fewer and smaller piping systems, valves and pumps (if utilized). Hybrid motors suffer two major drawbacks. The first, shared with solid rocket motors,

4000-457: Is responsible for the preparation of the spacecraft for launch, and remains in the LCC in an advisory capacity. The NASA Test Director is responsible for all pre-launch testing, whether involving the flight crew, the orbiter, the external tank/solid rocket booster, or ground support equipment. The NTD is also responsible for the safety of all personnel on the pad after fuelling has occurred. Reports to

4100-558: Is split into three categories according to total engine impulse : low-power, mid-power, and high-power . Hydrogen peroxide rockets are used to power jet packs , and have been used to power cars and a rocket car holds the all time (albeit unofficial) drag racing record. Corpulent Stump is the most powerful non-commercial rocket ever launched on an Aerotech engine in the United Kingdom. Launches for orbital spaceflights , or into interplanetary space , are usually from

Launch Control Center - Misplaced Pages Continue

4200-423: Is that the casing around the fuel grain must be built to withstand full combustion pressure and often extreme temperatures as well. However, modern composite structures handle this problem well, and when used with nitrous oxide and a solid rubber propellant (HTPB), relatively small percentage of fuel is needed anyway, so the combustion chamber is not especially large. The primary remaining difficulty with hybrids

4300-528: Is the only flown cryogenic oxidizer. Others such as FLOX, a fluorine /LOX mix, have never been flown due to instability, toxicity, and explosivity. Several other unstable, energetic, and toxic oxidizers have been proposed: liquid ozone (O 3 ), ClF 3 , and ClF 5 . Liquid-fueled rockets require potentially troublesome valves, seals, and turbopumps, which increase the cost of the launch vehicle. Turbopumps are particularly troublesome due to high performance requirements. The theoretical exhaust velocity of

4400-416: Is typically 69-70% finely ground ammonium perchlorate (an oxidizer), combined with 16-20% fine aluminium powder (a fuel), held together in a base of 11-14% polybutadiene acrylonitrile (PBAN) or Hydroxyl-terminated polybutadiene (polybutadiene rubber fuel). The mixture is formed as a thickened liquid and then cast into the correct shape and cured into a firm but flexible load-bearing solid. Historically,

4500-467: Is with mixing the propellants during the combustion process. In solid propellants, the oxidizer and fuel are mixed in a factory in carefully controlled conditions. Liquid propellants are generally mixed by the injector at the top of the combustion chamber, which directs many small swift-moving streams of fuel and oxidizer into one another. Liquid-fueled rocket injector design has been studied at great length and still resists reliable performance prediction. In

4600-496: The 'fire-dragon issuing from the water' (Huo long chu shui), thought to have been used by the Chinese navy. Medieval and early modern rockets were used militarily as incendiary weapons in sieges . Between 1270 and 1280, Hasan al-Rammah wrote al-furusiyyah wa al-manasib al-harbiyya ( The Book of Military Horsemanship and Ingenious War Devices ), which included 107 gunpowder recipes, 22 of them for rockets. In Europe, Roger Bacon mentioned firecrackers made in various parts of

4700-616: The Italian rocchetta , meaning "bobbin" or "little spindle", given due to the similarity in shape to the bobbin or spool used to hold the thread from a spinning wheel. Leonhard Fronsperger and Conrad Haas adopted the Italian term into German in the mid-16th century; "rocket" appears in English by the early 17th century. Artis Magnae Artilleriae pars prima , an important early modern work on rocket artillery , by Casimir Siemienowicz ,

4800-557: The Saturn V and Soyuz , have launch escape systems . This is a small, usually solid rocket that is capable of pulling the crewed capsule away from the main vehicle towards safety at a moments notice. These types of systems have been operated several times, both in testing and in flight, and operated correctly each time. This was the case when the Safety Assurance System (Soviet nomenclature) successfully pulled away

4900-628: The ammonium perchlorate used in most solid rockets when paired with suitable fuels. Some gases, notably oxygen and nitrogen, may be able to be collected from the upper atmosphere , and transferred up to low Earth orbit for use in propellant depots at substantially reduced cost. The main difficulties with liquid propellants are also with the oxidizers. Storable oxidizers, such as nitric acid and nitrogen tetroxide , tend to be extremely toxic and highly reactive, while cryogenic propellants by definition must be stored at low temperature and can also have reactivity/toxicity issues. Liquid oxygen (LOX)

5000-419: The mass flow rate of the propellants by their exhaust velocity relative to the rocket ( specific impulse ). A rocket can be thought of as being accelerated by the pressure of the combusting gases against the combustion chamber and nozzle , not by "pushing" against the air behind or below it. Rocket engines perform best in outer space because of the lack of air pressure on the outside of the engine. In space it

5100-409: The tally of APCP solid propellants is relatively small. The military, however, uses a wide variety of different types of solid propellants, some of which exceed the performance of APCP. A comparison of the highest specific impulses achieved with the various solid and liquid propellant combinations used in current launch vehicles is given in the article on solid-fuel rockets . In the 1970s and 1980s,

SECTION 50

#1732771806809

5200-576: The " ground segment ". Orbital launch vehicles commonly take off vertically, and then begin to progressively lean over, usually following a gravity turn trajectory. Rocket propellant Rocket propellant is used as reaction mass ejected from a rocket engine to produce thrust . The energy required can either come from the propellants themselves, as with a chemical rocket , or from an external source, as with ion engines . Rockets create thrust by expelling mass rear-ward, at high velocity. The thrust produced can be calculated by multiplying

5300-569: The 13th century. They also developed an early form of multiple rocket launcher during this time. The Mongols adopted Chinese rocket technology and the invention spread via the Mongol invasions to the Middle East and to Europe in the mid-13th century. According to Joseph Needham, the Song navy used rockets in a military exercise dated to 1245. Internal-combustion rocket propulsion is mentioned in

5400-572: The Congreve rocket in 1865. William Leitch first proposed the concept of using rockets to enable human spaceflight in 1861. Leitch's rocket spaceflight description was first provided in his 1861 essay "A Journey Through Space", which was later published in his book God's Glory in the Heavens (1862). Konstantin Tsiolkovsky later (in 1903) also conceived this idea, and extensively developed

5500-571: The L3 capsule during three of the four failed launches of the Soviet Moon rocket, N1 vehicles 3L, 5L and 7L . In all three cases the capsule, albeit uncrewed, was saved from destruction. Only the three aforementioned N1 rockets had functional Safety Assurance Systems. The outstanding vehicle, 6L , had dummy upper stages and therefore no escape system giving the N1 booster a 100% success rate for egress from

5600-551: The Launch Director. The Orbiter Test Conductor is in charge of all pre-flight checkout and testing of the orbiter, and manages the engineers in the firing room who monitor the orbiter's systems. OTC is an employee of a contractor rather than of NASA. The Payload Test Conductor is responsible for the pre-flight test and checkout of payloads carried by the orbiter and manages the engineering and test teams responsible for monitoring and controlling payload ground operations. PTC

5700-455: The O/F ratio may allow higher thrust levels. Once the rocket is away from the launchpad, the engine O/F ratio can be tuned for higher efficiency. Although liquid hydrogen gives a high I sp , its low density is a disadvantage: hydrogen occupies about 7 times more volume per kilogram than dense fuels such as kerosene. The fuel tankage, plumbing, and pump must be correspondingly larger. This increases

5800-466: The Russian RD-180 preburner, which burns LOX and RP-1 at a ratio of 2.72. Additionally, mixture ratios can be dynamic during launch. This can be exploited with designs that adjust the oxidizer to fuel ratio (along with overall thrust) throughout a flight to maximize overall system performance. For instance, during lift-off thrust is more valuable than specific impulse, and careful adjustment of

5900-634: The Soviet Katyusha rocket in the artillery role, and the American anti tank bazooka projectile. These used solid chemical propellants. The Americans captured a large number of German rocket scientists , including Wernher von Braun, in 1945, and brought them to the United States as part of Operation Paperclip . After World War II scientists used rockets to study high-altitude conditions, by radio telemetry of temperature and pressure of

6000-779: The Soviet Union ( Vostok , Soyuz , Proton ) and in the United States (e.g. the X-15 ). Rockets came into use for space exploration . American crewed programs ( Project Mercury , Project Gemini and later the Apollo programme ) culminated in 1969 with the first crewed landing on the Moon – using equipment launched by the Saturn V rocket. Rocket vehicles are often constructed in the archetypal tall thin "rocket" shape that takes off vertically, but there are actually many different types of rockets including: A rocket design can be as simple as

6100-531: The U.S. switched entirely to solid-fueled ICBMs: the LGM-30 Minuteman and LG-118A Peacekeeper (MX). In the 1980s and 1990s, the USSR/Russia also deployed solid-fueled ICBMs ( RT-23 , RT-2PM , and RT-2UTTH ), but retains two liquid-fueled ICBMs ( R-36 and UR-100N ). All solid-fueled ICBMs on both sides had three initial solid stages, and those with multiple independently targeted warheads had

SECTION 60

#1732771806809

6200-689: The atmosphere, detection of cosmic rays , and further techniques; note too the Bell X-1 , the first crewed vehicle to break the sound barrier (1947). Independently, in the Soviet Union's space program research continued under the leadership of the chief designer Sergei Korolev (1907–1966). During the Cold War rockets became extremely important militarily with the development of modern intercontinental ballistic missiles (ICBMs). The 1960s saw rapid development of rocket technology, particularly in

6300-419: The atmosphere. Multistage rockets are capable of attaining escape velocity from Earth and therefore can achieve unlimited maximum altitude. Compared with airbreathing engines , rockets are lightweight and powerful and capable of generating large accelerations . To control their flight, rockets rely on momentum , airfoils , auxiliary reaction engines , gimballed thrust , momentum wheels , deflection of

6400-625: The booster and spacecraft. Once the rocket has cleared the launch tower (usually within the first 10–15 seconds), is when control is switched over to the mission's relative mission control center. (The Christopher C. Kraft Jr. Mission Control Center at the Johnson Space Center in Houston, Texas for NASA launches or SpaceX Mission Control Center in Hawthorne, California for SpaceX launches.) Extensive renovation of Firing Room 4

6500-432: The case of bipropellant liquid rockets, a mixture of reducing fuel and oxidizing oxidizer is introduced into a combustion chamber , typically using a turbopump to overcome the pressure. As combustion takes place, the liquid propellant mass is converted into a huge volume of gas at high temperature and pressure. This exhaust stream is ejected from the engine nozzle at high velocity, creating an opposing force that propels

6600-410: The deflecting cowl at the nose. In 1920, Professor Robert Goddard of Clark University published proposed improvements to rocket technology in A Method of Reaching Extreme Altitudes . In 1923, Hermann Oberth (1894–1989) published Die Rakete zu den Planetenräumen ( The Rocket into Planetary Space ). Modern rockets originated in 1926 when Goddard attached a supersonic ( de Laval ) nozzle to

6700-463: The dynamics of rocket propulsion is due to William Moore (1813). In 1814, Congreve published a book in which he discussed the use of multiple rocket launching apparatus. In 1815 Alexander Dmitrievich Zasyadko constructed rocket-launching platforms, which allowed rockets to be fired in salvos (6 rockets at a time), and gun-laying devices. William Hale in 1844 greatly increased the accuracy of rocket artillery. Edward Mounier Boxer further improved

6800-414: The energy release per unit mass drops off quickly as the mixture ratio deviates from stoichiometric. LOX/LH 2 rockets are run very rich (O/F mass ratio of 4 rather than stoichiometric 8) because hydrogen is so light that the energy release per unit mass of propellant drops very slowly with extra hydrogen. In fact, LOX/LH 2 rockets are generally limited in how rich they run by the performance penalty of

6900-425: The engine like a pendulum in flight. However, the rocket veered off course and crashed 184 feet (56 m) away from the launch site , indicating that the rocket was no more stable than one with the rocket engine at the base. Rockets or other similar reaction devices carrying their own propellant must be used when there is no other substance (land, water, or air) or force ( gravity , magnetism , light ) that

7000-609: The exhaust stream , propellant flow, spin , or gravity . Rockets for military and recreational uses date back to at least 13th-century China . Significant scientific, interplanetary and industrial use did not occur until the 20th century, when rocketry was the enabling technology for the Space Age , including setting foot on the Moon . Rockets are now used for fireworks , missiles and other weaponry , ejection seats , launch vehicles for artificial satellites , human spaceflight , and space exploration . Chemical rockets are

7100-698: The film's scientific adviser and later an important figure in the team that developed the V-2 rocket. The film was thought to be so realistic that it was banned by the Nazis when they came to power for fear it would reveal secrets about the V-2 rockets. In 1943 production of the V-2 rocket began in Germany. It was designed by the Peenemünde Army Research Center with Wernher von Braun serving as

7200-460: The first launch in 1928, which flew for approximately 1,300 metres. These rockets were used in 1931 for the world's first successful use of rockets for jet-assisted takeoff of aircraft and became the prototypes for the Katyusha rocket launcher , which were used during World War II . In 1929, Fritz Lang 's German science fiction film Woman in the Moon was released. It showcased the use of

7300-410: The force (pressure times area) on the combustion chamber wall is unbalanced by the nozzle opening; this is not the case in any other direction. The shape of the nozzle also generates force by directing the exhaust gas along the axis of the rocket. Rocket propellant is mass that is stored, usually in some form of propellant tank or casing, prior to being used as the propulsive mass that is ejected from

7400-494: The grain (the 'port') widens and the mixture ratio tends to become more oxidizer rich. There has been much less development of hybrid motors than solid and liquid motors. For military use, ease of handling and maintenance have driven the use of solid rockets. For orbital work, liquid fuels are more efficient than hybrids and most development has concentrated there. There has recently been an increase in hybrid motor development for nonmilitary suborbital work: GOX (gaseous oxygen)

7500-445: The heating mechanism at high temperatures. Solar thermal rockets and nuclear thermal rockets typically propose to use liquid hydrogen for a specific impulse of around 600–900 seconds, or in some cases water that is exhausted as steam for a specific impulse of about 190 seconds. Nuclear thermal rockets use the heat of nuclear fission to add energy to the propellant. Some designs separate the nuclear fuel and working fluid, minimizing

7600-422: The launch operation as well as ensuring that downrange airspace and splashdown areas remain clear for launch, and monitors weather near the launch site. The Ground Launch Sequencer Engineer is responsible for monitoring the operation of the automated Ground Launch Sequencer system, which controls the countdown from T-9 minutes until launch. After this point through to T-31 seconds, they are in charge of implementing

7700-515: The local rate of combustion. This positive feedback loop can easily lead to catastrophic failure of the case or nozzle. Solid rocket propellant was first developed during the 13th century under the Chinese Song dynasty . The Song Chinese first used gunpowder in 1232 during the military siege of Kaifeng . During the 1950s and 60s, researchers in the United States developed ammonium perchlorate composite propellant (APCP). This mixture

7800-430: The majority of the thrust during the first 120 seconds. The main engines burned a fuel-rich hydrogen and oxygen mixture, operating continuously throughout the launch but providing the majority of thrust at higher altitudes after SRB burnout. Hybrid propellants: a storable oxidizer used with a solid fuel, which retains most virtues of both liquids (high ISP) and solids (simplicity). A hybrid-propellant rocket usually has

7900-440: The mass of the extra hydrogen tankage instead of the underlying chemistry. Another reason for running rich is that off-stoichiometric mixtures burn cooler than stoichiometric mixtures, which makes engine cooling easier. Because fuel-rich combustion products are less chemically reactive ( corrosive ) than oxidizer-rich combustion products, a vast majority of rocket engines are designed to run fuel-rich. At least one exception exists:

8000-482: The most common type of high power rocket, typically creating a high speed exhaust by the combustion of fuel with an oxidizer . The stored propellant can be a simple pressurized gas or a single liquid fuel that disassociates in the presence of a catalyst ( monopropellant ), two liquids that spontaneously react on contact ( hypergolic propellants ), two liquids that must be ignited to react (like kerosene (RP1) and liquid oxygen, used in most liquid-propellant rockets ),

8100-468: The motor is cast. Propellant combustion occurs inside the motor casing, which must contain the pressures developed. Solid rockets typically have higher thrust, less specific impulse , shorter burn times, and a higher mass than liquid rockets, and additionally cannot be stopped once lit. In space, the maximum change in velocity that a rocket stage can impart on its payload is primarily a function of its mass ratio and its exhaust velocity. This relationship

8200-479: The only way to launch spacecraft into orbit and beyond. They are also used to rapidly accelerate spacecraft when they change orbits or de-orbit for landing . Also, a rocket may be used to soften a hard parachute landing immediately before touchdown (see retrorocket ). Rockets were used to propel a line to a stricken ship so that a Breeches buoy can be used to rescue those on board. Rockets are also used to launch emergency flares . Some crewed rockets, notably

8300-426: The potential for radioactive contamination, but nuclear fuel loss was a persistent problem during real-world testing programs. Solar thermal rockets use concentrated sunlight to heat a propellant, rather than using a nuclear reactor. For low performance applications, such as attitude control jets, compressed gases such as nitrogen have been employed. Energy is stored in the pressure of the inert gas. However, due to

8400-470: The propellant is not burned but still undergoes a chemical reaction, and can be a 'monopropellant' such as hydrazine , nitrous oxide or hydrogen peroxide that can be catalytically decomposed to hot gas. Alternatively, an inert propellant can be used that can be externally heated, such as in steam rocket , solar thermal rocket or nuclear thermal rockets . For smaller, low performance rockets such as attitude control thrusters where high performance

8500-446: The propellant tanks are at a lower pressure than the combustion chamber, decreasing tank mass. For these reasons, most orbital launch vehicles use liquid propellants. The primary specific impulse advantage of liquid propellants is due to the availability of high-performance oxidizers. Several practical liquid oxidizers ( liquid oxygen , dinitrogen tetroxide , and hydrogen peroxide ) are available which have better specific impulse than

8600-509: The reduced volume of engine components. This means that vehicles with dense-fueled booster stages reach orbit earlier, minimizing losses due to gravity drag and reducing the effective delta-v requirement. The proposed tripropellant rocket uses mainly dense fuel while at low altitude and switches across to hydrogen at higher altitude. Studies in the 1960s proposed single-stage-to-orbit vehicles using this technique. The Space Shuttle approximated this by using dense solid rocket boosters for

8700-412: The rocket converts the thermal energy of the propellants into directed kinetic energy . This conversion happens in the time it takes for the propellants to flow from the combustion chamber through the engine throat and out the nozzle, usually on the order of one millisecond. Molecules store thermal energy in rotation, vibration, and translation, of which only the latter can easily be used to add energy to

8800-430: The rocket forward in accordance with Newton's laws of motion . Chemical rockets can be grouped by phase. Solid rockets use propellant in the solid phase , liquid fuel rockets use propellant in the liquid phase , gas fuel rockets use propellant in the gas phase , and hybrid rockets use a combination of solid and liquid or gaseous propellants. In the case of solid rocket motors, the fuel and oxidizer are combined when

8900-428: The rocket stage. Molecules with fewer atoms (like CO and H 2 ) have fewer available vibrational and rotational modes than molecules with more atoms (like CO 2 and H 2 O). Consequently, smaller molecules store less vibrational and rotational energy for a given amount of heat input, resulting in more translation energy being available to be converted to kinetic energy. The resulting improvement in nozzle efficiency

9000-414: The smaller and lighter tankage required. Upper stages, which mostly or only operate in the vacuum of space, tend to use the high energy, high performance, low density liquid hydrogen fuel. Solid propellants come in two main types. "Composites" are composed mostly of a mixture of granules of solid oxidizer, such as ammonium nitrate , ammonium dinitramide , ammonium perchlorate , or potassium nitrate in

9100-402: The surface area or oxidizer flux is high. Too high of oxidizer flux can lead to flooding and loss of flame holding that locally extinguishes the combustion. Surface area can be increased, typically by longer grains or multiple ports, but this can increase combustion chamber size, reduce grain strength and/or reduce volumetric loading. Additionally, as the burn continues, the hole down the center of

9200-549: The technical director. The V-2 became the first artificial object to travel into space by crossing the Kármán line with the vertical launch of MW 18014 on 20 June 1944. Doug Millard, space historian and curator of space technology at the Science Museum, London , where a V-2 is exhibited in the main exhibition hall, states: "The V-2 was a quantum leap of technological change. We got to the Moon using V-2 technology but this

9300-478: The vehicle's dry mass, reducing performance. Liquid hydrogen is also relatively expensive to produce and store, and causes difficulties with design, manufacture, and operation of the vehicle. However, liquid hydrogen is extremely well suited to upper stage use where I sp is at a premium and thrust to weight ratios are less relevant. Dense propellant launch vehicles have a higher takeoff mass due to lower I sp , but can more easily develop high takeoff thrusts due to

9400-519: The world in the Opus Majus of 1267. Between 1280 and 1300, the Liber Ignium gave instructions for constructing devices that are similar to firecrackers based on second hand accounts. Konrad Kyeser described rockets in his military treatise Bellifortis around 1405. Giovanni Fontana , a Paduan engineer in 1420, created rocket-propelled animal figures. The name "rocket" comes from

9500-535: Was fielded in the Napoleonic Wars . It was Congreve rockets to which Francis Scott Key was referring, when he wrote of the "rockets' red glare" while held captive on a British ship that was laying siege to Fort McHenry in 1814. Together, the Mysorean and British innovations increased the effective range of military rockets from 100 to 2,000 yards (91 to 1,829 m). The first mathematical treatment of

9600-567: Was finished in 2006. Firing Room 4 was leased by SpaceX and serves as their launch control center for Launch Complex 39A until August 2023 when the company moved into its own facility just before the launch of the Crew-7 mission. The Launch Director is the head of the launch team, and is responsible for making the final "go" or "no go" decision for launch after polling the relevant team members. There have been eight different Space Shuttle launch directors between 1981 and 2011. The Flow Director

9700-531: Was first printed in Amsterdam in 1650. The Mysorean rockets were the first successful iron-cased rockets, developed in the late 18th century in the Kingdom of Mysore (part of present-day India) under the rule of Hyder Ali . The Congreve rocket was a British weapon designed and developed by Sir William Congreve in 1804. This rocket was based directly on the Mysorean rockets, used compressed powder and

9800-498: Was launched to surveil enemy targets, however, recon rockets have never come into wide use in the military. Sounding rockets are commonly used to carry instruments that take readings from 50 kilometers (31 mi) to 1,500 kilometers (930 mi) above the surface of the Earth. The first images of Earth from space were obtained from a V-2 rocket in 1946 ( flight #13 ). Rocket engines are also used to propel rocket sleds along

9900-645: Was technology that was developed with massive resources, including some particularly grim ones. The V-2 programme was hugely expensive in terms of lives, with the Nazis using slave labour to manufacture these rockets". In parallel with the German guided-missile programme, rockets were also used on aircraft , either for assisting horizontal take-off ( RATO ), vertical take-off ( Bachem Ba 349 "Natter") or for powering them ( Me 163 , see list of World War II guided missiles of Germany ). The Allies' rocket programs were less technological, relying mostly on unguided missiles like

10000-570: Was used as the oxidizer for the Buran program 's orbital maneuvering system. Some rocket designs impart energy to their propellants with external energy sources. For example, water rockets use a compressed gas, typically air, to force the water reaction mass out of the rocket. Ion thrusters ionize a neutral gas and create thrust by accelerating the ions (or the plasma) by electric and/or magnetic fields. Thermal rockets use inert propellants of low molecular weight that are chemically compatible with

#808191