Ariane 5 (French: [aʁjan sɛ̃k]) is a retired European heavy-lift space launch vehicle operated by Arianespace for the European Space Agency (ESA). It was launched from the Guiana Space Centre (CSG) in French Guiana. It was used to deliver payloads into geostationary transfer orbit (GTO), low Earth orbit (LEO) or further into space. The launch vehicle had a streak of 82 consecutive successful launches between 9 April 2003 and 12 December 2017. In development since 2014, Ariane 6, a direct successor system was first launched in 2024.
The system was designed as an expendable launch vehicle by the Centre National d'Études Spatiales (CNES), the French government's space agency, in cooperation with various European partners. Despite not being a direct derivative of its predecessor launch vehicle program, it was classified as part of the Ariane rocket family. Aérospatiale, and later ArianeGroup, was the prime contractor for the manufacturing of the vehicles, leading a multi-country consortium of other European contractors. Ariane 5 was originally intended to launch the Hermes spacecraft, and thus it was rated for human space launches.
Since its first launch, Ariane 5 was refined in successive versions: "G", "G+", "GS", "ECA", and finally, "ES". The system had a commonly used dual-launch capability, where up to two large geostationary belt communication satellites can be mounted using a SYLDA (Système de Lancement Double Ariane, meaning "Ariane Double-Launch System") carrier system. Up to three, somewhat smaller, main satellites are possible depending on size using a SPELTRA (Structure Porteuse Externe Lancement Triple Ariane, which translates to "Ariane Triple-Launch External Carrier Structure"). Up to eight secondary payloads, usually small experiment packages or minisatellites, could be carried with an ASAP (Ariane Structure for Auxiliary Payloads) platform.
Following the launch of 15 August 2020, Arianespace signed the contracts for the last eight Ariane 5 launches, before it was succeeded by the new Ariane 6 launcher, according to Daniel Neuenschwander, director of space transportation at the ESA. Ariane 5 flew its final mission on 5 July 2023.
Ariane 5's cryogenic H173 main stage (H158 for Ariane 5G, G+, and GS) was called the EPC (Étage Principal Cryotechnique — Cryotechnic Main Stage). It consisted of a 5.4 m (18 ft) diameter by 30.5 m (100 ft) high tank with two compartments, one for liquid oxygen and one for liquid hydrogen, and a Vulcain 2 (Vulcain 1 for Ariane 5G, G+, and GS) engine at the base with a vacuum thrust of 1,390 kN (310,000 lbf). The H173 EPC weighed about 189 t (417,000 lb), including 175 t (386,000 lb) of propellant. After the main cryogenic stage runs out of fuel, it re-entered the atmosphere for an ocean splashdown.
Attached to the sides were two P241 (P238 for Ariane 5G and G+) solid rocket boosters (SRBs or EAPs from the French Étages d'Accélération à Poudre — lit. 'Powder Acceleration Stages'), each weighing about 277 t (611,000 lb) full and delivering a thrust of about 7,080 kN (1,590,000 lbf). They were fueled by a mix of ammonium perchlorate (68%) and aluminium fuel (18%) and HTPB (14%). They each burned for 130 seconds before being dropped into the ocean. The SRBs were usually allowed to sink to the bottom of the ocean, but, like the Space Shuttle Solid Rocket Boosters, they could be recovered with parachutes, and this was occasionally done for post-flight analysis. Unlike Space Shuttle SRBs, Ariane 5 boosters were not reused. The most recent attempt was for the first Ariane 5 ECA mission in 2009. One of the two boosters was successfully recovered and returned to the Guiana Space Center for analysis. Prior to that mission, the last such recovery and testing was done in 2003.
The French M51 submarine-launched ballistic missile (SLBM) shared a substantial amount of technology with these boosters.
In February 2000, the suspected nose cone of an Ariane 5 booster washed ashore on the South Texas coast, and was recovered by beachcombers before the government could get to it.
The second stage was on top of the main stage and below the payload. The original Ariane — Ariane 5G — used the EPS (Étage à Propergols Stockables — Storable Propellant Stage), which was fueled by monomethylhydrazine (MMH) and nitrogen tetroxide, containing 10,000 kg (22,000 lb) of storable propellant. The EPS was subsequently improved for use on the Ariane 5G+, GS, and ES.
The EPS upper stage was capable of repeated ignition, first demonstrated during flight V26 which was launched on 5 October 2007. This was purely to test the engine, and occurred after the payloads had been deployed. The first operational use of restart capability as part of a mission came on 9 March 2008, when two burns were made to deploy the first Automated Transfer Vehicle (ATV) into a circular parking orbit, followed by a third burn after ATV deployment to de-orbit the stage. This procedure was repeated for all subsequent ATV flights.
Ariane 5ECA used the ESC (Étage Supérieur Cryotechnique — Cryogenic Upper Stage), which was fueled by liquid hydrogen and liquid oxygen. The ESC used the HM7B engine previously used in the Ariane 4 third stage. The propellent load of 14.7 tonne allowed the engine to burn for 945 seconds while providing 6.5 tonne of thrust. The ESC provided roll control during powered flight and full attitude control during payload separation using hydrogen gas thrusters. Oxygen gas thrusters allowed longitudinal acceleration after engine cutoff. The flight assembly included the Vehicle Equipment Bay, with flight electronics for the entire rocket, and the payload interface and structural support.
The payload and all upper stages were covered at launch by a fairing for aerodynamic stability and protection from heating during supersonic flight and acoustic loads. It was jettisoned once sufficient altitude has been reached, typically above 100 km (62 mi; 54 nmi). It was made by Ruag Space and since flight VA-238 it was composed of 4 panels.
With the exception of the solid rocket boosters (for safety and cost reasons), the components were assembled in Europe, and then shipped to French Guyana by boat. Once at Kourou, the components were assembled in the Launcher Integration Building (BIL), then transferred into the Final Assembly Building (BAF) for mating the payload and fairing, before the completed rocket was transferred to the Launch Zone (ZL) for fueling and launch.
Launch pricing and market competition
As of November 2014, the Ariane 5 commercial launch price for launching a "midsize satellite in the lower position" was approximately €50 million, competing for commercial launches in an increasingly competitive market.
The heavier satellite was launched in the upper position on a typical dual-satellite Ariane 5 launch and was priced higher than the lower satellite, on the order of €90 million as of 2013.
Total launch price of an Ariane 5 – which could transport up to two satellites to space, one in the "upper" and one in the "lower" positions – was around €150 million as of January 2015.
Cancelled plans for future developments