ATV Launch on Track Despite Leaks, Moisture Build-Up

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  Space News Business

ATV Launch on Track Despite Leaks, Moisture Build-Up

By PETER B. de SELDING
Space News Staff Writer
posted: 05 December 2007
04:17 pm ET





PARIS —


Managers of the large European unmanned supply ship being readied for launch to the international space station in late January said Nov. 15 they




still meet that date despite the discovery of leaks in the vehicle’s propulsion valves, water-moisture buildup in its optical-sensor system, and the presence of




dust or other foreign material in its Russian-supplied docking system.

Those problems




were




uncovered during tests of the Automated Transfer Vehicle (ATV) at the Guiana Space Center spaceport in French Guiana. The vehicle, called Jules Verne, arrived in early August after a two-week ocean voyage in a specially designed ship.

ATV is a 1.3 billion euro ($1.9 billion) program financed by the European Space Agency (ESA). The vehicle spent three years undergoing tests at ESA’sEstec technology center in Noordwijk, Netherlands, before being sent to the launch base, where it is tentatively scheduled for launch aboard a modified Ariane 5 rocket.

ESA and European industry officials said here Nov. 16 that the anomalies found on the vehicle since arrival may have been caused by some event during the two-week ocean voyage.

“We are not sure if these were things we missed at Estec, but the fact is that we have allotted enough time at the launch site to perform the finely detailed analysis on ATV to make sure it is ready,” said Alberto Novelli, an ESA manager of the ATV Control Center, which is located on the Toulouse campus of the French space agency, CNES. “As of today I can tell you we are on track for the late-January launch.”

The moisture buildup in ATV’s optical sensors and its star tracker forced a replacement of these components with spares from Europe, a procedure that




now is being completed, officials said.

Similarly, leaks were found in certain propulsion valves for the ATV’s onboard motors, forcing replacement hardware to be sent from Europe.

ATV’s docking system is based on a well-proven Russian design by RSC Energia of Korolev, Russia. Officials discovered that the deployable, pencil-like point of the docking system, which first makes contact with its receiving end, attached to a Russian space station module, had a buildup of small particles that could have prevented it from extending into full position properly.

A minor cleanup of the component was undertaken.

ATV managers continue to negotiate with NASA and the Russian space agency, Roskosmos, on when ATV will be permitted to dock at the space station. A Russian unmanned Progress cargo supply ship and a U.S. space shuttle are scheduled to be at the station around the same time, which may complicate ATV’s docking.

Officials said they may resort to launching ATV as scheduled, then placing it into a parking orbit some 2,000 kilometers behind the station to wait for a time when the station’s traffic flow is eased before docking.

The Jules Verne ATV will carry about 7,000 kilograms of cargo. It is designed to travel to the station, stand off until permitted to approach, and then to dock automatically. It remains at the orbital complex for up to six months before being filled with garbage and sent on a controlled, destructive re-entry over the South Pacific.