http://www.parabolicarc.com/2009/07/06/vx200-demonstrates-superconducting-stage-full-power/
AD ASTRA ROCKET COMPANY PRESS RELEASE

Ad Astra Rocket Company has successfully demonstrated operation of its VX-200 plasma engine first stage at full power and under superconducting conditions in tests conducted today at the company's Houston laboratory. This achievement is a key milestone in the engine's development and the first time a superconducting plasma rocket has been operated at that power level.

Today's tests build on the achievements of the VX-200i, the engine's non-superconducting predecessor, which last fall underwent similar tests but under a greatly reduced set of requirements. A major difference between the two is the superconducting magnet, featured in the present system, which provides a ten-fold increase in the magnetic field and enables operation of the engine under conditions consistent with actual space flight.

The VX-200 superconducting magnet, the first of its kind, was delivered to Ad Astra's Houston facility on February 10, 2009 by its manufacturer, Scientific Magnetics of Oxford, U.K. After successful acceptance tests, the superconductor was installed in the engine module, replacing the conventional magnet that had been used in the interim. This interim magnet, although incapable of reaching the strong magnetic fields required for full rocket performance, enabled the integrated testing of the remaining engine sub-systems while the company awaited delivery of the superconductor. First plasma in full superconducting mode was achieved on June 24, 2009.

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