ATV re-boosts ISS to a higher orbit - New success for Astrium

Toulouse.– The Automated Transfer Vehicle (ATV) has successfully re-boosted the International Space Station (ISS) to a higher altitude.

“This was an important event for Astrium, as it validated one of the major tasks of the ATV’s inaugural flight, demonstrating the ability of the ‘Jules Verne’ to lift the ISS back into the correct orbit,” said Alain Charmeau, CEO of Astrium Space Transportation.

“The operation was performed with the same propulsion system used to manoeuvre the ATV itself. This ‘double use’ was taken into account from the outset of the project of the European Space Agency and incorporated in the design of the propulsion system, both in terms of the engines employed and the amount of fuel required,” explains Nicolas Chamussy, ATV Programme Manager at Astrium.

280 tons boosted by 4.7 kilometres

The orbital altitude of the ISS steadily declines as a result of atmospheric drag. It therefore has to be regularly re-boosted by increasing its speed, which causes it to rise. What is more, space debris circling the Earth sometimes crosses the orbital path of the space station and threatens to hit and puncture its inhabited sections, putting the lives of the crew at risk. The re-boost function makes it possible to perform escape manoeuvres to avoid such debris in the interest of crew safety.

The ISS is travelling at a speed of 7700 m/s and weighs 280 metric tons. The re-boost manoeuvre took 13 minutes. In accelerating the station by 2,67 m/s, the ATV was able to lift it by 4.7 kilometres. To do this, the computers on board the ISS ignited two of the ATV’s four main engines, generating a total thrust of 1000 newtons. This is equivalent to lifting 100 kg on Earth. If one of the two engines fails, the on-board control system is programmed to switch to the other two engines.

Such re-boost manoeuvres are carried out periodically (about once a month) to push the ISS back into position. The next manoeuvres are scheduled for June, July and August.