Materials on the outermost surface of spacecrafts have to satisfy stringent requirements regarding radiation (UV and otherwise), thermo-optical stability and outgassing among others. Some missions, for example in low earth orbit or approaching the atmosphere of other planets, must withstand further environmental influences, such as atomic oxygen (ATOX). Combined with very high temperatures due to the spacecraft's engines or from an external environment, dedicated materials must be used.

For this purpose, a glassfibre based woven material was developed and qualified for use as an outer material for application in harsh environments with high temperatures. The material is equipped with an electrical grid, to comply with electrical charging requirements. Furthermore, the material can be coated for use in MLI blankets.

The presented work describes the testing campaign performed for the qualification of the material for use as an outer layer close to the Ariane 6 upper stage and for the aerobraking surface for the EnVision mission, where the satellite will use the ATOX rich upper Venus atmosphere in order to descend into its science orbit.

The extensive test campaign included tensile tests at room and high temperature, thermo-gravimetric analysis, long-term high temperature exposure and outgassing evaluation at elevated temperatures.

A particularly interesting experiment was a combination of high heat flux and ATOX exposure. For this, a plasma wind tunnel test was performed on the Glass Fabric at sample level, together with other candidate materials. The samples were exposed to ATOX loads of 5 × 1021 cm-2 and a simultaneous heat flux of 7 kW m-2. The Glass Fabric showed a very high resistance to this exposure, with minimal changes to mass and thermo-optical properties. The sample showed no changes, neither to the base material nor to the stitching of the electrical grid.