On 9 July 2024 Europe’s new heavy-lift rocket, Ariane 6, finally made its inaugural flight from Europe’s Spaceport in French Guiana almost 500 km north of the equator after many initial delays and setbacks. This is an important breakthrough for the European Space Agency (ESA) and its partners.
The two-stage Ariane 6 is built by ArianeGroup a French company and operated by its subsidiary Arianespace on behalf of ESA.
The Ariane-6 is a project undertaken by ESA, which has 13 member states. This entire program is expected to cost around 4.5-billion-euro. The main contributors to this program are France (56%) and Germany (21%). Post Brexit, the UK continues to remain a member of ESA, however for this project, there is only some industry participation from its side. Interestingly, in spite of this being a European program, the Europe’s weather satellite operator EUMETSAT has decided not to opt for Ariane-6 and has chosen SpaceX’s Falcon-9, citing some exceptional circumstances for this decision.
The Ariane 6 is 56-62 m high – taller than the Leaning Tower of Pisa and weighs around 900 000 kg (900 tonnes), roughly equivalent to two fully loaded Boeing 747-8 airplanes. Ariane 6 has a modular structure consisting of three main portions stacked on top of each other: a main stage with either two or four boosters, an upper (orbital) stage and the payload in its fairing.
The main and upper stage – known together as the central core have been designed to efficiently deliver payloads to different orbits. The core stage is powered by the liquid-fueled Vulcain 2.1 engine, which is an upgraded version of the Vulcain 2 engine used for Ariane-5 launcher. The upper stage is powered by the Vinci engine. It has cryogenic liquid oxygen and hydrogen as propellants. This engine can restart multiple times and this is essential to precisely deliver payloads into different orbits.
Also Read: Outer Space: The future battlefield
Ariane-6 will be available in two versions: one with two boosters called Ariane 62, and another version with four boosters is called Ariane 64. It has been reported that the two booster versions can carry payloads up to 4.5 tonnes into Geostationary Transfer Orbit (GTO) or 10.3 tonnes into Low Earth Orbit (LEO) while Ariane 64 can carry approximately 11.5 tonnes into GTO and 21.6 tonnes into LEO.
The development of the Ariane 6 started in late 2014, and its debut was originally envisioned to take place in 2020, but the launch was delayed many times due to technical issues and problems, like the COVID-19 pandemic. As a result the project took around ten years to complete. The delays also meant that the Ariane 6 did not overlap with the Ariane 5, which flew 117 orbital missions from 1996 to 2023.
The Ariane-6 rocket is expected to enhance Europe’s abilities in the competitive space launch market. This rocket is expected to offer enhanced performance and cost saving, in comparison to its predecessor, the Ariane-5.
The Ariane-6 carried nine CubeSats into orbit, which were successfully deployed at an altitude of around 600 km above the Earth surface. It took 65 minutes to reach that altitude. The satellites also deployed two passengers from NASA, for checking the source of mysterious solar radio waves.
“This is the first time that someone is ever flying a radio interferometer in space in a controlled way, and so it’s a pathfinder for radio astronomy in general” a NASA statement claimed. The remaining satellites are meant for studying Earth’s climate and weather and for measuring highly energetic gamma rays.
Apart from dropping the satellites in space, the Ariane-6 was also supposed to deploy two experimental re-entry capsules after about two hours and 40 minutes of flight. The purpose behind this exercise was to demonstrate the thermal strength of the capsules to withstand very high temperatures. During the Earth’s atmosphere re-entry, these capsules can encounter temperatures almost around 2000 degrees Celsius. However, the Ariane-6’s upper stage did not complete a burn designed to set up that final deployment. The exact reasons for this error are not yet known. However, the rocket’s performance was satisfactory and hence the mission has been declared a success.
Based on the past history, it has been observed that there are failures in almost 50% cases during the first launch of any new rocket system. Even in the case of Ariane-5, the first launch was a failure in 1996. Subsequently, the Ariane-5 worked wonders and till date the launch vehicle has undertaken 117 launches with only five failures. This means a success rate of almost 96%. Knowing the reliability of the Ariane rocket systems already 29 missions have been booked for Ariane-6. There are plans to undertake 6 launches next year and eight during 2026. Eventually, the idea is to have a launch per month.
India has a longstanding relationship with Arianespace. A year back the CEO of Arianespace had visited ISRO headquarters at Bangalore. The Ariane Passenger Payload Experiment (APPLE) was ISRO’s first indigenous, experimental communication satellite and it was launched into GTO (Geosynchronous Transfer Orbit) by the third development flight of the Ariane vehicle from Kourou on June 19, 1981. Till date this company has launched more than 10 satellites for ISRO. India continues to have dependence on Ariane vehicles for launching heavy satellites since ISRO has capacity to launch satellites with a maximum of 4 ton payload capacity into geostationary orbit. ISRO has developed a cryogenic engine called CE-20 engine, which would be in use for the first un-crewed Gaganyaan mission. ISRO’s semi-cryogenic engine (SCE-200) development program has been underway since 2009. This engine is essential, if ISRO wants to launch 6 to 10 ton category satellites in higher orbits. On 1 July 2023, the first hot test with intermediate configuration of the semi-cryogenic engine was conducted. However, it is not yet clear how much more time would be required to operationalise the system.
Also Read: India’s odyssey in space – an insight
Today, India’s space industry, mainly the start-ups ecosystem, is doing some encouraging work. ISRO has a very good track record in providing assistance for launching satellites in LEO. ISRO’s LMV3 system in recent times has undertaken various successful commercial launches in LEO. Also, ISRO’s small satellite launch vehicle (SSLV) has demonstrated its capability towards launching mini/micro/nano satellites into LEO. To have a larger pie into the global launch market ISRO and India’s private space industry need to tie-up with Arianespace. Jointly both agencies can develop a model towards providing commercial launch services in multiple orbits.
