Ariane (rocket family)
Ariane is a series of a civilian European expendable launch vehicles for space launch use. The name comes from the French spelling of the mythological character Ariadne.
France first proposed the Ariane project in early 1973 and it was officially agreed upon at the end of 1973 after delicate discussions between France, Germany and the UK, thanks to the negotiating skills of Charles Hann, Belgian Minister of Research[citation needed]. 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 Centre Spatial Guyanais 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 non-restartable, powered by a single Aestus engine. The Ariane 5 first flight on 4 June 1996 failed.
The reason for the failure of the first launch is an interesting example of a system failing when all the components behaved correctly, according to their specifications. The vehicle self-destructed because parts of the flight control software, reused from the Ariane 4 series, went to overflow because the flight path of the Ariane 5 (which has a more horizontal and faster early trajectory compared to Ariane 4) had exceeded limits, specifically the horizontal distance travelled by the vehicle.
An upgraded version of Ariane 5 is designated "5-ECA" for Enhanced Capability-A. It has a cryogenic, non-restartable upper stage largely taken from Ariane 4, plus smaller improvements like an updated first-stage engine (Vulcain 2) and modified solid boosters (lighter casing, more fuel). Ariane 5-ECA is designed to carry a total 10 tonne payload into geostationary transfer orbit. It failed on its first flight on 11 December 2002. The fault laid in the Vulcain 2 engine nozzle which buckled due to an unexpected accumulation of thermal and mechanical stresses.
Launches continued with the original version, renamed Ariane 5G ("generic"), and the 5G+, which has some of the minor improvements of ECA without the cryogenic upper stage. Adding the solid boosters of the ECA will result in the 5GS. After redesign of the Vulcain 2 engine nozzle and considerable improvements to the entire vehicle, the second Ariane 5-ECA flight was successfully accomplished on 12 February 2005.
Ariane 5-ECB, with further improvements intended to carry 12 tonnes into geostationary transfer orbit, was cancelled in May 2005 due to lack of demand.
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.
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 1215 local time in the Val de Ruz in the Canton of Neuchâtel, Switzerland.