European Space Cargo Ship Tests Going Well

PARIS — Europe's Automated Transfer Vehicle (ATV) cargo vessel March 14 successfully completed a key test of its emergency-abort sequence, performing a collision-avoidance maneuver that ground teams hope will never be needed when the time comes to dock with the international space station, European Space Agency (ESA) officials said.

In the maneuver, the 41,887-pound (19,000-kilogram) ATV, named Jules Verne after the 19th century French science fiction writer, was stopped in its tracks and thrown into reverse, firing four of its thrusters to move backwards at a speed of around 16.4 feet per second (5 meters per second) to simulate a slow retreat from the space station.

It is this maneuver that will be required if, as it approaches the station for a planned April 3 docking, its speed, approach angle or some other parameter poses a safety concern for the station and its astronauts.

The March 14 test also demonstrated the ability of ATV to switch to its independent backup computer, which would be required only if there are multiple failures of the main computer system, which has its own backup.

ATV managers say it is a highly unlikely scenario, but one that must be planned for given the delicate nature of having a machine the size of ATV approach the station.

With its main computers shut off, the ATV automatically placed itself into survival mode, pointing toward the sun to continue to feed its four power-generating solar arrays to await further instructions from ground teams.

About 95 minutes after the reverse-thrust command, the vessel's main computers were switched back on. It will now remain in its current orbit of some 190 miles (305 kilometers) in altitude until March 18, when it will begin its transition into higher orbit as it prepares its approach to the space station. The station's current orbit is about 211 miles (340 kilometers) in altitude.

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• VIDEO: Part 2: Jules Verne, Europe's First ISS Cargo Tug
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