In
spaceflightSpaceflight is the use of space technology to achieve the flight of spacecraft into and through outer space.Spaceflight is used in space exploration, and also in commercial activities like space tourism and satellite telecommunications...
, a
launch vehicle or
carrier rocket is a
rocketA rocket or rocket vehicle is a missile, spacecraft, aircraft or other vehicle which obtains thrust by the reaction of the rocket to the ejection of a jet of fast moving fluid exhaust from a rocket engine. Chemical rockets create their exhaust by the combustion of rocket propellant...
used to carry a payload from the Earth's surface into
outer spaceOuter space comprises the relatively empty regions of the universe outside the atmospheres of celestial bodies. Outer space is used to distinguish it from airspace and terrestrial locations....
. A
launch system includes the launch vehicle, the
launch padA launch pad is the area and facilities where rockets or spacecrafts liftoff. A Spaceport can contain one or many launch pads. A typical launch pad consists of the service and umbilical structures. The service structure provides an access platform to inspect the launch vehicle prior to launch....
and other infrastructure.
Usually the payload is an artificial
satelliteIn the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavor. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
placed into
orbitIn physics, an orbit is the gravitationally curved path of one object around a point or another body, for example the gravitational orbit of a planet around a star....
, but some spaceflights are
sub-orbitalA sub-orbital spaceflight is a spaceflight in which the spacecraft reaches space, but its trajectory intersects the atmosphere or surface of the gravitating body from which it was launched, so that it does not complete one orbital revolution....
while others enable
spacecraftA spacecraft is a craft or machine designed for spaceflight. On a sub-orbital spaceflight, a spacecraft enters space then returns to the Earth. For an orbital spaceflight, a spacecraft enters a closed orbit around the planetary body. Spacecraft used for human spaceflight carry people on board as...
to
escapeIn physics, escape velocity is the speed where the kinetic energy of an object is equal to the magnitude of its gravitational potential energy, as calculated by the equation,...
Earth orbit entirely. A launch vehicle which carries its payload on a suborbital trajectory is often called a
sounding rocketA sounding rocket, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The origin of the term comes from nautical vocabulary, it refers to to sound, which means to throw a weighted...
.
Expendable launch vehicles are designed for one-time use.
In
spaceflightSpaceflight is the use of space technology to achieve the flight of spacecraft into and through outer space.Spaceflight is used in space exploration, and also in commercial activities like space tourism and satellite telecommunications...
, a
launch vehicle or
carrier rocket is a
rocketA rocket or rocket vehicle is a missile, spacecraft, aircraft or other vehicle which obtains thrust by the reaction of the rocket to the ejection of a jet of fast moving fluid exhaust from a rocket engine. Chemical rockets create their exhaust by the combustion of rocket propellant...
used to carry a payload from the Earth's surface into
outer spaceOuter space comprises the relatively empty regions of the universe outside the atmospheres of celestial bodies. Outer space is used to distinguish it from airspace and terrestrial locations....
. A
launch system includes the launch vehicle, the
launch padA launch pad is the area and facilities where rockets or spacecrafts liftoff. A Spaceport can contain one or many launch pads. A typical launch pad consists of the service and umbilical structures. The service structure provides an access platform to inspect the launch vehicle prior to launch....
and other infrastructure.
Usually the payload is an artificial
satelliteIn the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavor. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
placed into
orbitIn physics, an orbit is the gravitationally curved path of one object around a point or another body, for example the gravitational orbit of a planet around a star....
, but some spaceflights are
sub-orbitalA sub-orbital spaceflight is a spaceflight in which the spacecraft reaches space, but its trajectory intersects the atmosphere or surface of the gravitating body from which it was launched, so that it does not complete one orbital revolution....
while others enable
spacecraftA spacecraft is a craft or machine designed for spaceflight. On a sub-orbital spaceflight, a spacecraft enters space then returns to the Earth. For an orbital spaceflight, a spacecraft enters a closed orbit around the planetary body. Spacecraft used for human spaceflight carry people on board as...
to
escapeIn physics, escape velocity is the speed where the kinetic energy of an object is equal to the magnitude of its gravitational potential energy, as calculated by the equation,...
Earth orbit entirely. A launch vehicle which carries its payload on a suborbital trajectory is often called a
sounding rocketA sounding rocket, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The origin of the term comes from nautical vocabulary, it refers to to sound, which means to throw a weighted...
.
Types of launch vehicles
Expendable launch vehicles are designed for one-time use. They usually separate from their payload, and may break up during
atmospheric reentryAtmospheric reentry refers to the movement of human-made or natural objects as they enter the atmosphere of a planet from outer space, in the case of Earth from an altitude above the "edge of space." This article primarily addresses the process of controlled reentry of vehicles which are intended...
. Reusable launch vehicles, on the other hand, are designed to be recovered intact and used again for subsequent launches. For
orbital spaceflightAn orbital spaceflight is a spaceflight in which a spacecraft is placed on a trajectory where it could remain in space for at least one orbit. To do this around the Earth, it must be on a free trajectory which has an altitude at perigee above...
s, the
Space ShuttleThe Space Shuttle, part of the Space Transportation System , is a spacecraft operated by NASA for orbital human spaceflight missions. It began operations in the 1980s and is scheduled to be retired from service in 2010 after 134 launches...
is currently the only launch vehicle with components which have been used for multiple flights.
Non-rocket spacelaunchNon-rocket spacelaunch is the idea of reaching outer space specifically from the Earth's surface predominately without the use of conventional chemical rockets, which today is the only method in use....
alternatives are at the planning stage.
Launch vehicles are often characterized by the amount of mass they can lift into orbit. For example, a
Proton rocketProton is an expendable launch system used for both commercial and Russian government space launches. The first Proton rocket was launched in 1965 and the launch system is still in use as of 2009, which makes it one of the most successful heavy boosters in the history of spaceflight...
has a launch capacity of into
low Earth orbitA low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...
(LEO). Launch vehicles are also characterized by the number of
stagesA multistage rocket is a rocket that usestwo or more stages, each of which contains its own engines and propellant. A tandem or serial stage is mounted on top of another stage; a parallel stage is attached alongside another stage. The result is effectively two or more rockets stacked on top of...
they employ. Rockets with as many as five stages have been successfully launched, and there have been designs for several
single-stage-to-orbitA single-stage-to-orbit vehicle reaches orbit from the surface of a body without jettisoning hardware, expending only propellants and fluids. The term usually, but not exclusively, refers to reusable vehicles....
vehicles. Additionally, launch vehicles are very often supplied with boosters, which supply high thrust early on in the flight, and normally in parallel with other engines on the vehicle. Boosters allow the remaining engines to be smaller, which reduces the burnout mass of later stages, and thus allows for larger payloads.
Other frequently-reported characteristics of launch vehicles are the nation or space agency responsible for the launch, and the company or consortium that manufactures and launches the vehicle. For example, the
European Space Agency|owner = |headquarters = Paris|spaceport = Guiana Space Centre|image = ESA LOGO.svg|size = 240px|acronym = ESA|established = 1975|administrator = Jean-Jacques Dordain...
is responsible for the Ariane V, and the
United Launch AllianceUnited Launch Alliance is a joint venture of Lockheed Martin and Boeing formed in December 2006. ULA combines the teams at these companies which provide spacecraft launch services to the government of the United States. U.S...
manufactures and launches the
Delta IVDelta IV is an active expendable launch system in the Delta rocket family. Delta IV uses rockets designed by Boeing's Integrated Defense Systems division and built in the United Launch Alliance facility in Decatur, Alabama. Final assembly is completed at the launch site by ULA...
. Many launch vehicles are considered part of an historical line of vehicles which share the same or similar names such as the
Atlas VAtlas V is an active expendable launch system in the Atlas rocket family. Atlas V was formerly operated by Lockheed Martin, and is now operated by the Lockheed Martin-Boeing joint venture United Launch Alliance...
being the latest member of the
AtlasAtlas is a family of U.S. space launch vehicles. The original Atlas missile was designed in the late 1950s. It was a liquid-fuel rocket burning LOX and RP-1 in three engines configured in an unusual "stage-and-a-half" or "Parallel Staging" design: two of its three engines were jettisoned during...
rocket family.
Vehicle assembly
Various methods are used to move an assembled launch vehicle onto its launch pad, each method with its own specialized equipment. These assembly activities take place as part of the overall
launch campaignIn the context of spaceflight, a launch campaign is the set of activities which prepare a launch vehicle for lift-off.Activities during the launch campaign include launch vehicle assembly, integration of the payload, fueling of the vehicle, and preparing the launch pad, the launch range and...
for the vehicle. In some launch systems, like the
Delta IIDelta II is a space launch system originally designed and built by McDonnell Douglas. Delta II is part of the Delta rocket family and has been in service since 1989...
, the vehicle is assembled vertically on the pad, using a crane to hoist each stage into place. The
Space ShuttleThe Space Shuttle, part of the Space Transportation System , is a spacecraft operated by NASA for orbital human spaceflight missions. It began operations in the 1980s and is scheduled to be retired from service in 2010 after 134 launches...
orbiter, including its external tank, and
solid rocket boostersThe Space Shuttle Solid Rocket Boosters are the pair of large solid rockets used by the space shuttle during the first two minutes of powered flight. Together they provide about 83% of liftoff thrust for the Space Shuttle. They are located on either side of the orange external propellant tank...
, are assembled vertically in
NASAThe National Aeronautics and Space Administration is an agency of the United States government, responsible for the nation's public space program. NASA was established by the National Aeronautics and Space Act on July 29, 1958, replacing its predecessor, the National Advisory Committee for...
's
Vehicle Assembly BuildingThe Vehicle Assembly Building, or VAB, is located at NASA's Kennedy Space Center. It is the fourth largest building in the world by volume. The building is halfway between Jacksonville and Miami, and due east of Orlando on Merritt Island on the Atlantic coast of Florida...
, and then a special
crawler-transporterThe crawler-transporters are a pair of tracked vehicles used to transport spacecraft from NASA's Vehicle Assembly Building along the Crawlerway to Launch Complex 39. They were originally used to transport the Saturn IB and Saturn V rockets during the Apollo, Skylab and Apollo-Soyuz programs. ...
moves the entire stack to the launch pad while it is in an upright position. In contrast, the Soyuz rocket is assembled horizontally in a processing hangar, transported horizontally, and then brought upright once at the pad.
Derivation and related terms
In the English language, the phrase carrier rocket was used earlier, and still is occasionally, in Britain. A translation of that phrase is used in German, Russian, and Chinese. In the 1950s, the US Air Force disliked the term
carrier due to the competitive nature of their relationship with the US Navy and their high profile operation of
aircraft carrierAn aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power great distances without having to depend on local bases for staging aircraft operations...
s. As an alternative,
Project VanguardProject Vanguard was a program managed by the United States Naval Research Laboratory , which intended to launch the first artificial satellite into Earth orbit using a Vanguard rocket as the launch vehicle....
provided a contraction of the phrase "Satellite Launching Vehicle" abbreviated to "SLV". This provided a term in the list of what the rockets were allocated for: flight test, or actually launching a satellite. The contraction would also apply to rockets which send probes to other worlds or the interplanetary medium.
Orbital launch vehicles
Sounding rocketA sounding rocket, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its sub-orbital flight. The origin of the term comes from nautical vocabulary, it refers to to sound, which means to throw a weighted...
s are normally used for brief, inexpensive space and microgravity experiments. Current human-rated suborbital launch vehicles include
SpaceShipOneSpaceShipOne is a rocket-powered aircraft that completed the first privately funded human spaceflight on June 21, 2004. It was developed by Scaled Composites....
and the upcoming SpaceShipTwo, among others (see
space tourismSpace tourism is the recent phenomenon of tourists paying for flights into space.As of 2009, orbital space tourism opportunities are limited and expensive, with only the Russian Space Agency providing transport...
).
The
delta-vIn astrodynamics, the term delta-v, literally "change in velocity" , has a specific meaning: it is a scalar which takes units of speed that measures the amount of "effort" needed to carry out an orbital maneuver, i.e., to change from one trajectory to another.Where is the instantaneous thrust is...
needed for orbital launch is generally between , although there is no upper limit. How much delta-v is needed can be determined by using a combination of air-drag, which is determined by
ballistic coefficientIn ballistics the ballistic coefficient of a body is a measure of its ability to overcome air resistance in flight. It is inversely proportional to the deceleration—a high number indicates a low deceleration. BC is a function of mass, diameter, and drag coefficient...
,
gravity lossesIn astrodynamics and rocketry, gravity drag is a measure of the loss in the net performance of a rocket while it is thrusting in a gravitational field...
,
altitude gainPotential energy is energy stored within a physical system as a result of the position or configuration of the different parts of that system. It is called potential energy because it has the potential to be converted into other forms of energy, such as kinetic energy, and to do work in the process...
and the
horizontal speedThe kinetic energy of an object is the extra energy which it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its current velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its...
necessary to give a suitable perigee. The delta-v required for altitude gain varies, but is around for altitude.
Minimising air-drag entails having a reasonably high ballistic coefficient, which generally means having a launch vehicle that is about long. Vehicles which use hydrogen fueled stages should be even longer, since hydrogen has such low density. Leaving the atmosphere as early on in the flight as possible provides an air drag of around . The horizontal speed necessary to acheave low earth orbit is around .
The calculation of the total delta-v for launch is complicated, and in nearly all cases numerical integration is used; adding multiple delta-v values provides a pessimistic result, since the rocket can thrust while at an angle in order to reach orbit, thereby saving fuel as it can gain altitude and horizontal speed simultaneously.
Regulation
Under international law, the nationality of the owner of a launch vehicle determines which country is responsible for any damages resulting from that vehicle. Due to this, some countries require that rocket manufacturers and launchers adhere to specific regulations in order to indemnify and protect the safety of people and property that may be affected by a flight.
In the US, any rocket launch that is not classified as amateur, and also is not "for and by the government," must be approved by the
Federal Aviation AdministrationThe Federal Aviation Administration is an agency of the United States Department of Transportation with authority to regulate and oversee all aspects of civil aviation in the U.S...
's
Office of Commercial Space TransportationThe Office of Commercial Space Transportation is the branch of the United States Federal Aviation Administration that approves any commercial rocket launch operations—that is, any launches that are not classified as model, amateur, or "by and for the government."-Overview:Under...
(FAA/AST), located in Washington, DC
See also
Specific to launch vehicles
- List of launch vehicles
- Comparison of small lift launch systems
For this article, small-capacity launch systems are defined as being those capable of lifting less than 2,000 kg to low Earth orbit.-Notes:A. Includes suborbital launchesB. Has not yet conducted a successful orbital launchC...
- Comparison of medium lift launch systems
For this article, medium-capacity launch systems are determined as being those capable of lifting at least 2,000kg, but less than 20,000kg to low Earth orbit.-See also:* Comparison of small lift launch systems* Comparison of mid-heavy lift launch systems...
- Comparison of mid-heavy lift launch systems
This page compares launch systems which are submitted to international competition and able to launch 3,000 to 9,000 kilogram satellites to a geosynchronous transfer orbit .- See also :* Comparison of small lift launch systems...
- Comparison of heavy lift launch systems
When comparing launch systems, those capable of lifting the most mass to orbit use Heavy Lift Launch Vehicles. The phrase "heavy lift" has often been applied to vehicles like Saturn V, Titan IV, Ariane 5, Proton, and Delta IV-Heavy...
- NATO reporting name
NATO reporting names are unclassified code names for military equipment of the Eastern Bloc...
, Sheldon namesSheldon names were used to identify launch vehicles of the Soviet Union when their Soviet names were unknown. The system was published by Dr. Charles Sheldon of the United States Library of Congress in 1968...
General links
- Rocket launch
A rocket launch is the first phase of the flight of a rocket. Launches for orbital spaceflights, or launches into interplanetary space, are usually from a fixed location on the ground, but may also be from a floating platform such as the San Marco platform, or the Sea Launch launch vessel.Launches...
- Space logistics
-Definition:The activity of maintaining human and robotics operations in space. This includes planning and carrying out the movement of humans and materiel to, from, and within space....
- Space Exploration
Space exploration is the use of astronomy and space technology to explore outer space. Physical exploration of space is conducted both by human spaceflights and by robotic spacecraft....