Ariane (rocket)
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Ariane is a series of a European civilian expendable launch vehicles for space launch use. The name comes from the French spelling of the mythological character Ariadne; the word is also used as the name of a type of hummingbird.
France first proposed the Ariane project in early and it was officially agreed upon at the end of 1973 after delicate discussions between France, Germany and the UK. The project was Western Europe's second attempt to develop its own launcher following the unsuccessful Europa project. The Ariane project was code-named L3S (the French acronym for third-generation substitution launcher). The European Space Agency (ESA) has oversight of the development of all Ariane launchers and of the testing facilities; while Arianespace, a commercial entity created in 1980, handles production, operations and marketing.
Arianespace launches Ariane rockets from the Guiana Space Center at Kourou in French Guiana, where the proximity to the equator gives a significant advantage for the launch.
The several versions of the launcher include:
- Ariane 1, first successful launch on December 24, 1979
- Ariane 2, first successful launch on November 20, 1987 (the first launch on May 30, 1986 failed)
- Ariane 3, first successful launch on August 4, 1984
- Ariane 4, first successful launch on June 15, 1988
- Ariane 5, first successful launch on October 30, 1997 (the first launch on June 4, 1996 failed).
Ariane 1 was a 3-stage launcher, derived from missile technology. Arianes 2 through 4 are enhancements of the basic vehicle. The major differences are improved versions of the engines, allowing stretched first- and third-stage tanks and greater payloads. The largest versions can launch two satellites, mounted in the SPELDA (Structure Porteuse Externe pour Lancements Doubles Ariane) adapter.
Such later versions are often seen with strap-on boosters. These layouts are designated by suffixes after the generation number. First is the total number of boosters, then letters designating liquid- or solid-fuelled stages. For example, an Ariane 42P is an Ariane 4 with 2 solid-fuel boosters. An Ariane 44LP has 2 solid, 2 liquid boosters, and a 44L has 4 liquid-fuel boosters.
Ariane 5 is a nearly-complete redesign. The two storable lower stages are replaced with a single, cryogenic core stage. This simplifies the stack, along with the use of a single core engine (Vulcain). Because the core cannot lift its own weight, two solid-fuel boosters are strapped to the sides. The boosters can be recovered for examination but are not reused. The upper stage is storable and restartable, powered by a single Aestus engine.[1]
As with many rockets, the initial flights of each new Ariane model have seen failures. However, overall, the Ariane 4 and 5 are the most reliable commercial rockets ever launched. As of January 2006, 169 Ariane flights have boosted 290 satellites, successfully placing 271 of them on orbit (223 main passengers and 48 auxiliary passengers) for a total mass of 575 000 kg successfully delivered on orbit. This success rate also makes Arianespace the foremost commercial launcher; in some years, more than two thirds of all commercial satellites have been launched with the company's vehicles.
In addition, the Ariane 5 is capable of launching the heaviest loads available. On 27 May 2006, an Ariane 5-ECA rocket set a new commercial payload record, lifting 2 satellites with a combined mass of 8.2 tonnes. [2]
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[edit] Models
Flyable models of the Ariane 4 and 5 are available as kits from Noris Raketen in Germany. In 1987 Lambert Shelter built a 5.40 metre long flyable model of the Ariane, now displayed at the Hermann Oberth Space Travel Museum in Feucht. A 4.5 m, 85 kg flyable model of the Ariane 4, built by the Advanced Rocketry Group Of Switzerland (ARGOS), was launched in 2002 in Amarillo, Texas and successfully again on 19 September 2004 at 12:15 local time in the Val de Ruz in the Canton of Neuchâtel, Switzerland.
[edit] References
British SkyNet Satellite launch on Ariane 5
