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Information about Expendable Launch System

An expendable launch system uses an expendable launch vehicle (ELV) to launch a payload into outer space. This type of launch vehicle is designed to be used only once, and its components are not recovered after the launch. The vehicle typically consists of several rocket stages, discarded one by one as the vehicle gains altitude and speed.

Design rationale

The ELV design differs from that of a reusable launch system, where the vehicle would be launched and recovered more than once. This might seem to make the ELV design a more expensive launch method, but in practice launches using ELVs have been less expensive than launches on the Space Shuttle, which is the only existing launch vehicle that is even partly reusable. (See Space Shuttle Program and Criticism of the Space Shuttle program for discussion of Space Shuttle economics). Most satellites are currently launched using expendable launchers; they are perceived as having a low risk of mission failure, a short time to launch and a relatively low cost.

There have also been proposals for (as-yet theoretical) single stage to orbit systems. In principle an expendable single stage to orbit vehicle would be impossible; it is generally more efficient to use staging when the vehicle is not meant to be recovered intact.

History

Most orbital expendable launchers are derivatives of 1950s-era ballistic missiles. The Magellan probe was the first planetary spacecraft launched by a Space Shuttle.

Many see it as unfortunate that most "modern" orbital expendables are derived from ballistic missiles, as these missiles were built to Cold War specs and with Cold War budgets, and argue that this makes for horrendously expensive launch vehicles. A prime example of this is the Titan IV, probably the costliest per-unit launch vehicle in history (perhaps following the Space Shuttle).

On the other hand, reusable launchers have to be built more robustly and thus carry extra dry weight to orbit, and require recovery systems, and thus everything else being equal (to a similarly constructed expendable), would have a very much smaller payload. Reusable launchers would thus not necessarily be enormously cheaper.

Development

Main article: Private spaceflight

European sponsorship

Main article: Arianespace
On March 26, 1980, the European Space Agency and the Centre National d'Etudes Spatiales (CNES) created Arianespace, the world's first commercial space transportation company. Arianespace produces, operates and markets the Ariane launcher family. By 1995 Arianespace lofted its 100th satellite and by 1997 the Ariane rocket had its 100th launch.[1] Arianespace's 23 shareholders represent scientific, technical, financial and political entities from 10 different European countries. The major shareolder is the CNES, with 32,53% of capital.[2]

American deregulation

From the beginning of the Shuttle program until the Challenger disaster in 1986, it was the policy of the United States that NASA be the public-sector provider of U.S. launch capacity to the world market.[3] Initially NASA subsidized satellite launches with the intention of eventually pricing Shuttle service for the commercial market at long-run marginal cost.

On October 30, 1984, United States President Ronald Reagan signed into law the Commercial Space Launch Act.[4] This enabled an American industry of private operators of expendable launch systems. Prior to the signing of this law, all commercial satellite launches in the United States were limited to NASA's Space Shuttle.

On November 5, 1990, United States President George H. W. Bush signed into law the Launch Services Purchase Act.[5] The Act, in a complete reversal of the earlier Space Shuttle monopoly, ordered NASA to purchase launch services for its primary payloads from commercial providers whenever such services are required in the course of its activities.

Russian privatization

The Russian government sold part of its stake in RSC Energia to private investors in 1994. Energia together with Khrunichev constituted most of the Russian manned space program. In 1997, the Russian government sold off enough of its share to lose the majority position.

American subsidization

Main article: Evolved Expendable Launch Vehicle
In 1996 the United States government selected Lockheed Martin and Boeing to each develop Evolved Expendable Launch Vehicles (EELV) to compete for launch contracts and provide assured access to space. The government's acquisition strategy relied on the strong commercial viability of both vehicles to lower unit costs. This anticipated market demand did not materialize, but both the Delta IV and Atlas V EELVs remain in active service.

Launch alliances

Since 1995 Khrunichev's Proton rocket is marketed through International Launch Services while the Soyuz rocket is marketed via Starsem. Energia builds the Soyuz rocket and owns part of the Sea Launch project which flies the Ukrainian Zenit rocket.

In 2003 Arianespace joined with Boeing Launch Services and Mitsubishi Heavy Industries to create the Launch Services Alliance. In 2005, continued weak commercial demand for EELV launches drove Lockheed Martin and Boeing to propose a joint venture called the United Launch Alliance to monopolize the United States government launch market.[6]

Today many commercial space transportation companies offer launch services to satellite companies and government space organizations around the world. In 2005 there were 18 total commercial launches and 37 non-commercial launches.[7] Russia flew 44% of commercial orbital launches, while Europe had 28% and the United States had 6%.

See also

External links

References

1. ^ [1]
2. ^ [2]
3. ^ [3]
4. ^ [4]
5. ^ [5]
6. ^ [6]
7. ^ [7]


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List of expendable launch vehicles
Current:
Planned:
Historical:
Outer space, sometimes simply called space, refers to 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).
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launch vehicle or carrier rocket is a rocket used to carry a payload from the Earth's surface into outer space. A launch system includes the launch vehicle, the launch pad and other infrastructure.
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rocket is a vehicle, missile or aircraft which obtains thrust by the reaction to the ejection of fast moving fluid from within a rocket engine.

The history of rockets goes back to at least the 13th century[1].
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multistage (or multi-stage) rocket is a rocket that uses two or more stages, each of which contains its own engines and propellant. A stacked stage is mounted on top of another stage; a parallel stage is attached next to another stage.
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A reusable launch system (or RLV: reusable launch vehicle) is a launch vehicle which is capable of launching into space more than once. This contrasts with expendable launch systems, where each launch vehicle is launched once and then discarded.
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Space Shuttle

Space Shuttle Atlantis on the launch pad prior to the STS-115 mission.
Fact sheet
Function Manned partially re-usable launch and reentry system
Manufacturer United Space Alliance:
Thiokol/Boeing (SRBs)
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Space Shuttle, officially called Space Transportation System (STS), is the United States government's current manned launch vehicle. The winged Shuttle Orbiter is launched vertically, usually carrying five to seven astronauts (although eight have been carried) and up
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The primary negative criticisms of the Space Shuttle program are:
  • It failed in the goal of greatly reducing the cost of space access (e.g. a 'Space Truck'). Space shuttle incremental per-pound launch costs are not appreciably cheaper than that of expendable launchers.

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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.
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A single-stage-to-orbit (or SSTO) 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.
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orbital spaceflight (or orbital flight) 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 (altitude at closest
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worldwide view.


2nd millennium
Centuries: 19th century - 20th century - 21st century

1920s 1930s 1940s - 1950s - 1960s 1970s 1980s
1950 1951 1952 1953 1954
1955 1956 1957 1958 1959

- -
- The 1950s
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ballistic missile is a missile that follows a sub-orbital, ballistic flightpath with the objective of delivering a warhead to a predetermined target. The missile is only guided during the relatively brief initial powered phase of flight and its course is subsequently governed by
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Magellan spacecraft was a space probe sent to the planet Venus, the first post-Voyager unmanned spacecraft to be launched by NASA since its successful Voyager 1 spacecraft to Jupiter and Saturn in 1977.
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The Cold War was the period of conflict, tension and competition between the United States and the Soviet Union and their respective allies from the mid-1940s until the early 1990s.
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The Titan IV family (including the IVA and IVB) of space boosters were used by the US Air Force. They were launched from Cape Canaveral Air Force Station, Florida, and Vandenberg Air Force Base, California.

The Titan IV was retired in 2005.
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Private spaceflight is flight above 100km Earth altitude conducted by and paid for by an entity other than a government. In the early decades of the Space Age, the government space agencies of the Soviet Union and United States pioneered space technology in collaboration with
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A French company, founded in 1980, Arianespace SA[1] undertakes the production, operation and marketing of the Ariane 5 rocket launcher as part of the Ariane programme. It was the world's first commercial space transportation company.
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March 26 is the 1st day of the year (2nd in leap years) in the Gregorian calendar. There are 0 days remaining.

Events

  • 1026 - Pope John XIX crowns Conrad II as Holy Roman Emperor.

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19th century - 20th century - 21st century
1950s  1960s  1970s  - 1980s -  1990s  2000s  2010s
1977 1978 1979 - 1980 - 1981 1982 1983

Year 1980 (MCMLXXX
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European Space Agency (ESA), established in 1974, is an inter-governmental organisation dedicated to the exploration of space, currently with 17 member states. Its headquarters are in Paris.
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Centre National d'Études Spatiales (CNES) is the French government space agency (administratively, a "public establishment of industrial and commercial character"). Its headquarters are located in central Paris.
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A French company, founded in 1980, Arianespace SA[1] undertakes the production, operation and marketing of the Ariane 5 rocket launcher as part of the Ariane programme. It was the world's first commercial space transportation company.
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Ariane is a feminine name. It is a French translation of the Greek name Ariadne. Ariane is also an historical region in Asia (see Ariana, Aria).

People named Ariane
  • Princess Ariane of the Netherlands
  • Ariane Ehrat, a Swiss alpine skier

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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.
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A shareholder or stockholder is an individual or company (including a corporation) that legally owns one or more shares of stock in a joint stock company. A company's shareholders collectively own that company. Thus, such companies strive to enhance shareholder value.
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Europe is one of the seven traditional continents of the Earth. Physically and geologically, Europe is the westernmost peninsula of Eurasia, west of Asia. Europe is bounded to the north by the Arctic Ocean, to the west by the Atlantic Ocean, to the south by the Mediterranean Sea,
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Space Shuttle Challenger disaster occurred in the United States, over the Atlantic Ocean, off the coast of central Florida, at 11:39 a.m. EST (16:39 UTC) on January 28 1986.
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In economics and finance, marginal cost is the change in total cost that arises when the quantity produced changes by one unit. Mathematically, the marginal cost (MC) function is expressed as the derivative of the total cost (TC) function with respect to quantity (Q).
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October 30th is the feast day of the following Roman Catholic Saints:
  • St. Artemas
  • St. Herbert
  • St.
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