Ariane 6 () is a European expendable launch system developed for the European Space Agency (ESA) and French Space Agency (CNES) and manufactured by a consortium of European companies, led by the prime contractor ArianeGroup. As part of the Ariane rocket family, it is operated by Arianespace, replacing the Ariane 5. The project's primary contributors were France (55.3%), Germany (21%) and Italy (7.6%), with the remaining work distributed among ten other participating countries.
This two-stage rocket utilizes liquid hydrogen and liquid oxygen (hydrolox) engines. The first stage features an upgraded Vulcain engine from Ariane 5, while the second uses the Vinci engine, designed specifically for this rocket. The Ariane 62 variant uses two P120C solid rocket boosters, while Ariane 64 uses four. The P120C booster is shared with Europe's other launch vehicle Vega C, and is an improved version of the P80 used on the original Vega.
Selected in December 2014 over an all-solid-fuel alternative, Ariane 6 was initially planned for a 2020 debut. However, the program faced delays, with the first launch eventually taking place on 9 July 2024. While the rocket successfully launched, the mission experienced a partial failure when the upper stage malfunctioned and was not able to complete its final deorbit burn. The second launch was therefore postponed to 6 March 2025, successfully delivering its first commercial payload to orbit, the CSO-3 reconnaissance satellite.Next Ariane 6 launch slips to early 2025, Jeff Foust, SpaceNews, 8 November 2024.
Ariane 6 was designed to reduce launch costs and increase annual launch capacity from seven to eleven missions compared with its predecessor. , the targeted launch rate has not yet been achieved, although when measured by cost per kilogram to orbit, costs have been reduced by 40%. The program has faced criticism over its development costs and lack of reusability compared with competing vehicles such as SpaceX's Falcon 9. European officials have defended the program, stating that it ensures independent access to space for participating member states.
Description Three variants of Ariane 6 are offered:
Ariane 62 (A62), with two P120C solid boosters, weighs around at liftoff and is mainly for government and scientific missions. It can launch up to into geosynchronous transfer orbit (GTO) and into low Earth orbit (LEO). The first launch in July 2024 used this variant. Ariane 64 (A64), with four P120C boosters, has a liftoff weight of around and is intended for commercial dual-satellite launches of up to into GTO and into LEO. Like Ariane 5, it is able to launch two geosynchronous satellites together. This variant was first launched in February 2026. Ariane 64 Block 2, with four P160C boosters, extended by to carry an additional of propellant. Also uses an enhanced Vinci upper stage engine with increased thrust of . Together, these changes resulted in a gain of to low Earth orbit. This variant was first launched in June 2026.
Rocket components are transported by sea from Europe to the Guiana Space Centre aboard the Canopée, a cargo vessel that uses sails to assist with its propulsion, reducing fuel use.
First stage The first (lower) stage of Ariane 6 is called the Lower Liquid Propulsion Module (LLPM). It is powered by a single Vulcain 2.1 engine fuelled by liquid hydrogen (LH2) with liquid oxygen (LOX). The LLPM is in diameter and contains approximately of propellant.
Boosters
Additional thrust is provided by either P120C or P160C model solid rocket boosters, designated in Ariane 6 nomenclature as Equipped Solid Rockets (ESR). Each P120C booster contains approximately of propellant and delivers up to of thrust.
The P120C and P160C are also used as the first stage of the upgraded Vega C launcher, allowing increased production volumes and reduced unit costs through commonality. They are improved versions of the P80 motor used on the original Vega.
Second stage
The second (upper) stage of Ariane 6 is called the Upper Liquid Propulsion Module (ULPM). It shares the same diameter as the LLPM and is also fuelled by LH2 and LOX. It is powered by the Vinci engine, which delivers of thrust, burns for up to 900 seconds and is capable of up to five restarts. The ULPM carries about of propellant and has a dry mass of .
Fairing The payload fairing, constructed by Beyond Gravity from a carbon fibre-polymer composite, is designed as a nose cone that splits vertically into two halves at the top of the Ariane 6 rocket. It is available in two sizes: a long version and a short version, both with a diameter of . The interior of the cylindrical payload compartment is in diameter and the long variant measures in height, or when including the conical portion of the fairing. As of August 2026, only Amazon Leo launches have used the long fairing in the A64L configuration.
Future upgrades
ASTRIS The Ariane Smart Transfer and Release In-orbit Ship (ASTRIS) was originally conceived as a kick stage for Ariane 6 to place payloads into higher or otherwise different orbits, but in November 2025 the European Space Agency approved its evolution into a space tug. Designed as an optional addition to Ariane 6's upper stage, ASTRIS will have a steerable, restartable main engine, allowing it to place payloads directly into their operational orbits, including separate orbits for multiple payloads on a single launch and trajectories for missions to the Moon, Mars and asteroids. Ground qualification is expected by the end of 2028, with the first flight planned for 2029.
Crew rating The European Space Agency is exploring human-rating certification for Ariane 6, awarding Arianespace a contract to explore potential options for enabling crewed missions to be launched aboard the vehicle.
History Ariane 6 was conceived in the early 2010s to be a replacement launch vehicle for Ariane 5, and a number of concepts and high-level designs were suggested and proposed during 2012–2015. Development funding from several European governments was secured by early 2016, and contracts were signed to begin detailed design and the build of test articles. In 2019, the maiden orbital flight had been planned for 2020, however by May 2020, the planned initial launch date was delayed into 2021. In October 2020, the European Space Agency (ESA) formally requested an additional in funding from the countries sponsoring the project to complete development of the rocket and get the vehicle to its first test flight, which had slipped to the second quarter of 2022. By June 2021, the date had delayed to late 2022. In June 2022, a delay was announced to "some time in 2023" and by October 2022, ESA clarified that the first launch would be no earlier than the fourth quarter of 2023, while providing no public reason for the delay. In August 2023, ESA announced that the date for the first launch had slipped again to 2024.
Concept and early development: 2010–2015
Following detailed definition studies in 2012, ESA announced in July 2013 the selection of Ariane 6's PPH (first stage of three P145 rocket motors, second stage of one P145 rocket motor, and H32 cryogenic upper stage) configuration for Ariane 6. It would be capable of launching up to to Geostationary transfer orbit (GTO), with a first flight projected to be as early as 2021–2022. Development was projected to cost €4 billion . A 2014 study concluded that development cost could be reduced to about €3 billion by limiting contractors to five countries.
While Ariane 5 typically launches one large and one medium satellite at a time, the PPH proposal for Ariane 6 was intended for single payloads, with an early 2014 price estimate of approximately US$95 million per launch. The SpaceX Falcon 9 and the Chinese Long March 3B both launch smaller payloads but at lower prices, approximately $57 million and $72 million respectively as of early 2014, making the Falcon 9 launch of a midsize satellite competitive with the cost of the lower slot of a dual payload Ariane 5. For lightweight all-electric satellites, Arianespace intended to use the restartable Vinci engine to deliver the satellites closer to their operational orbit than the Falcon 9 could, thus reducing the time required to transfer to geostationary orbit by several months.
Ariane 6.1 and Ariane 6.2 proposals In June 2014, Airbus and Safran surprised ESA by announcing a counter proposal for the Ariane 6 project: a 50/50 joint venture to develop the rocket, which would also involve buying out the French government's CNES interest in Arianespace.
This proposed launch system would come in two variants, Ariane 6.1 and Ariane 6.2. While both would use a cryogenic main stage powered by a Vulcain 2 engine and two P145 solid boosters, Ariane 6.1 would feature a cryogenic upper stage powered by the Vinci engine and boost up to to GTO, while Ariane 6.2 would use a lower-cost hypergolic upper stage powered by the Aestus engine. Ariane 6.1 would have the ability to launch two electrically powered satellites at once, while Ariane 6.2 would be focused on launching government payloads.
French newspaper La Tribune questioned whether Airbus Defence and Space could deliver on the promised costs for their Ariane 6 proposal, and whether Airbus and Safran Group could be trusted when they were found to be responsible for a failure of Ariane 5 flight 517 in 2002 and a more recent 2013 failure of the M51 ballistic missile. The companies were also criticised for being unwilling to incur development risks, and asking for higher initial funding than originally planned instead of . Estimated launch prices of for Ariane 6.1 and for Ariane 6.2 did not compare favourably to SpaceX offerings. During the meeting of EU ministers in Geneva on 7 June 2014, these prices were deemed too high and no agreement with manufacturers was reached.
Ariane 62 and Ariane 64 proposals
Following criticism of the Ariane 6 PPH design, France unveiled a revised Ariane 6 proposal in September 2014. This launcher would use a cryogenic main stage powered by the Vulcain 2 and upper stage powered by the Vinci but vary the number of solid boosters. With two P120C boosters, Ariane 6 would launch up to to GTO at a cost of €75 million. With four boosters, Ariane 6 would be able to launch two satellites totalling to GTO at a cost of €90 million.
This proposal, unlike Ariane 6 PPH, offered a scalable launcher while retaining Ariane 5's dual-launch capability. The proposal also included simplification of the industrial and institutional organisation along with a better and cheaper version of the Vulcain 2 engine for the main stage. Although Ariane 6 was projected to have "lower estimated recurring production costs", it was projected to have "a higher overall development cost owing to the need for a new, Ariane 6-dedicated, launch pad".
The Italian, French, and German space ministers met on 23 September 2014, in order to plan strategy and assess the possibility for agreement on funding for the Ariane 5 successor, and in December 2014, ESA selected the Ariane 62 and Ariane 64 designs for development and funding.
At the 2022 International Astronautical Congress, ArianeGroup announced the proposed "Smart Upper Stage for Innovative Exploration", a reusable upper stage for the 64 (or later) variant, capable of autonomous cargo operations or carrying five astronauts to LEO.
Test vehicle development: 2016–2021
In November 2015, an updated design of Ariane 64 and 62 was presented, with new nose cones on the boosters, main stage diameter increased to , and the height decreased to .