We had the great pleasure to visit the ArianeGroup facility in Les Mureaux in France. We were extremely lucky to be one of the very few Social Media reporters selected for this extraordinary event.
We (my boss SpaceHolgar was joining to give some support) were starting our journey to Paris with high hopes and a thrill of anticipation. We were leaving our hotel in the morning to be transported by bus directly to the facilities of ArianeGroup in the town Les Mureaux. Immediately after a nice introduction about ArianeGroup and the site itself the tour of the facilities begun.
And we were starting our tour with visiting the huge main assembly hall where the big main stage of the very reliable and commercially successful ESA launcher Ariane 5 is assembled. After some introduction this impressive video was shown to us:
After watching the video we had the pleasure to enter the observation deck with a direct overview look into the assembly hall. We were able to spot three Ariane 5 main stages in different phases of assembly. As you can see in the images (surprisingly we were allowed to take pics of almost everything – a premiere at this site to my knowledge) Ariane 5 main stages are assembled vertically. As the main stages are about 30 meters tall (with a diameter of 5.4 meters) the assembly hall needs to be even taller. This yields to quite a challenge for the air conditioning of the entire hall making it complicated and leading to some remarkable costs – as we were told.
To be allowed to get a view into the main assembly hall from the observation deck was already great. But it was getting better and better: We were allowed to enter the main assembly hall directly! Woohoo! What a fantastic surprise!
The first Ariane 5 component I was spotting in the main assembly hall I had seen before at a different site. It was a so called Forward Skirt for an Ariane 5 main stage. It will be mounted at the top of the tank section of the main stage and has the forward connection points for the Solid Rocket Motors. Inside of the skirt most of the avionics – the brain of the launcher – is installed. And now I remmber where I have spotted a forward skirt like this one already: during visiting my friends of the German company MT Aerospace in Augsburg some months ago. In Augsburg several important components for the Ariane 5 launcher like tank domes for the main and upper stages and the steel segments for the Solid Rocket Motors are being built.
Many other components for the Ariane 5 main stage are being produced in different European countries and then delivered to ArianeGroup in Les Mureaux for assembly. One of these components is the Thrust Structure which is being produced in the Netherlands. Here in Les Mureaux it is mounted below the tank section of the main stage. Its main purpose is to transfer the forces of thrust from the Vulcain 2 main engine to the main structure of the stage. Additionally, the lower connection points for the SRMs are located at the Thrust Structure.
The Vulcain 2 main engine is being mounted directly below the Thrust Structure. And we had the pleasure to have a look at one of these engines with all the details (no photos here obsviously).
Wide angle video view of the assembly hall for the Ariane 5 main stage:
The two tanks of the Ariane 5 main stage (one for super cooled liquid hydrogen with a temperature of -254 deg Celsius and one for cooled liquid oxygen of -183 deg Celsius) reach the main hall already in assembled state. The thermal insulation is added to the walls of the tanks in the main hall. It consists of light grey insulation sheets that are glued to the surface of the tanks. Their main purpose is to avoid that ice is forming at the walls of the tanks during the fueling process. Without insulation the walls would get that cold that a thick layer of water ice would form from the humidity in the air. The ice would pose a risk during early phases of launch. Therefore the formation of ice has to be avoided.
In Les Mureaux the Ariane 5 main stages are prepared to be almost ready for launch. The are shipped in big and very special containers for transportation via the river Seine and the Atlantic Ocean to reach the European spaceport in Kourou in the North of South America.
Visiting the main assembly hall for the Ariane 5 main stage was a really fascinating highlight of visiting Les Mureaux. But that was not all. We had the pleasure to see how double launch structures called SYLDA are manufactured and learned a lot about the future European launcher Ariane 6. I will tell you more stunning facts about this in the next parts of my report of this great visit in Les Mureaux soon. Thank you.
Part II: The SYLDA double launch structure