Tim Furniss/LONDON

A Soyuz booster is scheduled to test the new Fregat upper stage for Franco-Russian venture Starsem. The test will be carried out after its launch on 9 February. The mission will also test new inflatable re-entry technology heatshields developed by Lavochkin and DaimlerChrysler Aerospace.

The Fregat will carry a payload simulating the European Space Agency Cluster satellites that the new upper stage is to place into orbit in June and July. Another Soyuz test is planned before the first Cluster mission. The Fregat is destined to be used for Starsem missions on a variety of science and Earth observation craft and for potential missions to geostationary transfer orbit.

The $1.8 million Inflatable Re-entry and Descent Technology (IRDT) project, which also involves the European Commission, was initiated nine months ago. Its goal is to make possible the re-entry and recovery of space payloads which do not have heavy heatshields and recovery parachute systems. Also on trial is a similar, 14m (45ft)-diameter Fregat Recovery System planned to return the upper stage to earth.

The shields work by initially partially inflating, reducing re-entry velocity and heating and later fully inflating to break the final descent and impact.

During the February Soyuz-Fregat mission, the upper stage and a small Argentine research payload will reach a 600km (370 mile) orbit. The instrumented payload will use the 4m-diameter IRDT and the Fregat will circle the Earth five times. The stage will fire again, acting as a retro-rocket and both payloads will re-enter separately, encased in conical inflatable re-entry shields to protect them from the heat. It is hoped that the payloads will be recovered in Russia.

Source: Flight International