The two massive boosters, propellers attached along the rocket’s main body, rip the 770-tonne monster out of the ground and consume the 240 tons of gunpowder each contains in just two minutes. At the same time, the powerful Vulcain 2 engine swallows in eight minutes the 225 tons of liquid oxygen and hydrogen needed to pull Ariane 5 out of Earth’s gravity.
And then allow the rocket’s upper stage to drop the two satellites into their transfer orbit, from where they will position themselves 36,000 kilometers from Earth. The weight of the two machines, Malaysian and Indian, is around 10 tons.
Preparation for flight VA257, for flight 257 of an Ariane rocket, began almost two years ago with the arrival of the first raw sheets at the Arianegroup factory in Les Mureaux, near Paris, to shape the tanks of the rocket main stage.
Once manufactured, the various elements of the launcher were transported to Kourou where the 29-day launch campaign began: assembly of the various elements, filling of the satellite tanks before their installation under the launcher’s fairing.
In addition to the interruption of the launch of Russian Soyuz rockets from Guyana, which reduces the activity of the space center, the war in Ukraine has upset the plans: the satellites could not be transported by the large Ukrainian Antonov plane as is usually the case.
The Malaysian satellite “Measat-3d arrived by ship, (the Indian) Gsat-24 in an Indian Air Force C-17 transport plane,” says Bruno Gérard, director of Arianespace and Arianegroup in Kourou.
On the eve of launch, the rocket is still in its final assembly building (BAF), resting on its launch table.
One of the last pre-launch operations begins: the transfer of the rocket to the launch pad located a few kilometers over a railway line on the senator’s train at 4 km/h. All that remains is to fill the tanks.
“We never fill the BAF with liquid oxygen and hydrogen, it’s too dangerous,” explains Bruno Gérard.
Three kilometers from the launch platform, in the bunker of a first control center, the “launcher’s cabin”, about fifty engineers and operators, each one behind his desk, ensure the good health of the rocket and its not Shooting.
“We woke up the launcher to do the final checks,” explains Bruno Erin, mission leader for Arianespace.
In Jupiter’s control room, the launch “control tower,” all flight parameters are scrutinized, from radar and telemetry to monitor the rocket in flight, to weather forecasts, and even “backup media.” to ensure “neutralization” of the launcher in the event of a problem.
“We don’t press a button to take off. As long as there is no negative parameter, we do not stop the launch”, summarizes Raymond Boyce, director of operations of the National Center for Space Studies (Cnes), which manages space. center.
After this launch number 113 of Ariane 5, a rocket that began its journey in 1996, there are only four flights left, two this year and two in 2023.
One of them is emblematic: the European Space Agency’s (ESA) Juice mission to the icy moons of Jupiter.
Not enough to feed a disproportionate nostalgia for so much. “There will be a bit of sadness, there will be Ariane 5 veterans just as there were Ariane 4 veterans,” said Daniel de Chambure, director of ESA’s Kourou office.
Bruno Gérard only expects a “little pang in the heart”. “But whatever the launcher, it’s always the same job and the Ariane 6 is coming,” tempers this veteran, whose first flight was the “VA19”, an Ariane 3 in 1987.
The first flight of Ariane 6, more flexible and less expensive than Ariane 5, and therefore more competitive in the face of fierce competition from the American SpaceX, has been postponed to 2023.