Space Rider's ALEK in LEAF on Vega third stage

A part of the orbital module for the European Space Agency’s reuseable spacecraft Space Rider in the LEAF facility at the Agency’s technical heart in The Netherlands, 28 March 2025.

Space Rider is a versatile reuseable spacecraft about the size of two minivans that allows for all kind of missions, from pharmaceutical research to visiting orbital platforms and more. After missions that can last up to three months, Space Rider returns to Earth, and precision-lands on skids after a paraglider descent.

While in orbit Space Rider relies on a Vega-C rocket fourth stage called AVUM+ (Attitude Vernier Upper Module) with a new element built by Beyond Gravity for Avio, called ALEK (AVUM Life Extension Kit). The rocket fourth stage provides propulsion to move and orient the spacecraft and the ALEK provides electricity and other services needed for the orbital life of the vehicle with two solar panel wings. Together these elements make up the expendable orbital module that separates from the Space Rider reentry module before its return to Earth.

ALEK’s structure spent two months at ESA’s testing facility being put through the full range of mechanical tests and stresses it will experience when launched on a Vega-C rocket.

ALEK's last test was a shock test, checking the service module would hold it together when it separates from the Vega-C rocket that propels it to orbit. For this test, Alek was placed on top of a model of the fourth stage of Vega-C, equipped to simulate some the shocks that are generated by the rocket on ascent, verifying how the shocks are transferred through the structure. The shock test was performed in the same acoustic chamber, LEAF.

The largest European facility of its kind, ESA's Large European Acoustic Facility (LEAF) is a test chamber measuring 11 m wide by 9 m deep and 16.4 m high. Its walls are made of steel-reinforced concrete 0.5 m thick to contain the sound and are coated with a thick coating of epoxy resin to reduce noise absorption and increase internal reverberation.

One wall is fitted with noise horns of the same basic design as those seen in stereo speakers which can produce noise equivalent to multiple jet aircraft lifting off simultaneously from 30 metres away.