The European Space Agency (ESA) has awarded two contracts to MT Aerospace and ArianeGroup to develop a prototype upper stage to help build enhanced composite upper stage technologies for the Ariane 6 rocket.

The technology maturation contracts will see MT Aerospace and ArianeGroup work together to design and test the Prototype of a Highly OptimizEd Black Upper Stage (PHOEBUS).

ESA wants to highlight the potential of composite technologies to improve the competitiveness and performance of the Ariane 6 launcher. A key advantage of composites is that they can be used to create new architectures and combinations of functions.

Phoebus will incorporate carbon composite materials in the metallic tanks containing the cryogenic propellants such as liquid hydrogen and oxygen. The materials will also be used for other primary and secondary structures.

ESA project manager Josef Wiedemann said: “Future composite upper stages will look very different to those of today.

“Carbon composites will replace much of the metal thereby reducing the mass and offering new opportunities to redefine the architecture of the upper stage, depending on mission requirements.”

The development of the PHOEBUS prototype could pave the way for technologies for upper stage upgrades.

According to the space agency, using composite materials instead of aluminium to build the upper stage will help reduce the Ariane 6 launch costs and increase its payload capacity for geostationary orbit by two metric tonnes.

The technologies developed by MT Aerospace and ArianeGroup will be integrated into an upper stage demonstrator from 2021 to prove compatibility with liquid oxygen and hydrogen on a large scale.

“Carbon composites will replace much of the metal thereby reducing the mass and offering new opportunities to redefine the architecture of the upper stage.”

As part of the collaborative efforts, ArianeGroup will handle innovative stage architectures and system integration.

An affiliate of OHB space and technology group, MT Aerospace will focus on developing materials and technologies for composite tanks and structures under cryogenic conditions.

PHOEBUS will lead to further product development of the Ariane 6 upper stage, known as Innovative Carbon Ariane Upper Stage (Icarus).

The new upper stage will be made of carbon-fibre reinforced plastic (CFRP).

ArianeGroup is the prime contractor for the development of Ariane 6 launcher.