BBC News
watch One-Minute World News
Last Updated: Wednesday, 12 March 2008, 06:31 GMT
Space freighter's propulsion fix
By Jonathan Amos
Science reporter, BBC News

'JULES VERNE' STATISTICS
ATV artist's impression (Astrium)
Total cargo: 4,860kg
1,340kg - 'dry' supplies
20kg - air (oxygen/nitrogen)
280kg - drinking water
860kg - propellant for ISS
2,360kg - re-boost propellant
The ship itself has 3,490kg of propellant for rendezvous, re-boost and de-orbit manoeuvres

Europe's space freighter, the ATV, has had its propulsion system fully restored after an earlier glitch had closed down a quarter of its thrusters.

Mission controllers in Toulouse sent up commands to the vehicle on Tuesday that brought the thrusters and an electronic control box back online.

The truck has now begun the climb to the space station from the 260km-high orbit in which it was initially placed.

The ATV is expected to dock with the platform on 3 April.

It is carrying just under five tonnes of food, water, air, fuel and equipment for the station's astronauts.

The Automated Transfer Vehicle - dubbed Jules Verne for this mission - is the biggest, most complex spacecraft ever flown by the European Space Agency (Esa).

The truck has advanced systems that allow it to find its own way to the 340km-high station and dock with it.

The freighter is the way Europe will pay for its membership of the International Space Station (ISS) project. Four vehicles will follow this initial flight.

Redundant systems

The ATV cannot approach the station until after space shuttle Endeavour, launched on Tuesday, has completed its mission.

The vehicle will use the time to practise stop-go manoeuvres, including a demonstration of its collision avoidance capability. This is an emergency stop and rapid reverse.

This would be used if something went wrong in the final approach and there was a danger of the freighter crashing into the platform.

Jules Verne was launched on Sunday by an Ariane 5 rocket from the Kourou spaceport in French Guiana.

Shortly after it was deployed, engineers received data indicating a large difference in pressures between the oxidiser and the fuel going through one of the ATV's four "propulsion chains". These are complex networks of pipes and valves leading from the fuel tanks to the thrusters.

As a precaution, the anomalous chain - comprising seven of the ATV's 28 attitude control jets and one of its four main engines - was shut down.

Spare propulsion capacity on the spacecraft meant the freighter's operation was never compromised, but engineers said they wanted to resolve the glitch as soon as possible.

That fix was initiated on Tuesday and involved first disabling all the propulsion chains before then progressively bringing them all back online.

ATV at the ISS (Astrium)


Jonathan.Amos-INTERNET@bbc.co.uk



SEE ALSO
Space truck orbits despite fault
10 Mar 08 |  Science/Nature
Huge space truck races into orbit
09 Mar 08 |  Science/Nature
European spaceport's sky-high ambition
07 Mar 08 |  Science/Nature
A key moment in Europe's space journey
08 Feb 08 |  Science/Nature
Space cargo ship near completion
30 Jan 08 |  Science/Nature
Europe's 'big bird' nears flight
13 Nov 07 |  Science/Nature
Europe prepares huge space truck
29 Jun 07 |  Science/Nature

RELATED INTERNET LINKS
The BBC is not responsible for the content of external internet sites



FEATURES, VIEWS, ANALYSIS
Has China's housing bubble burst?
How the world's oldest clove tree defied an empire
Why Royal Ballet principal Sergei Polunin quit

PRODUCTS & SERVICES

Americas Africa Europe Middle East South Asia Asia Pacific