Fibrous composites with ceramic matrix are prospective as structural materials for high temperature applications in an oxidative environment because they are tougher than brittle technical ceramics. The project aims at optimising the manufacturing process of heat-resistant fibrous composites with a ceramic matrix derived by pyrolysis from commercially available polysiloxane resins. Kinetics of chemorheological behaviour of the resins and evolution of their dielectric properties during curing will be pursued. For this purpose, measurement devices will be designed and developed. Dielectric analysis will be employed for optimisation and partial automation or the composite curing process with the aim to achieve its satisfactory mechanical properties and oxidation resistance at elevated temperatures. Ceramic fibres (Nicalon and Nextel) will be utilized to reinforce the composites with the design resistance up to 1000°C, while carbon and S-glass fibres will be employed for lower temperatures. Relations between microstructure and performance of the manufactured materials will be investigated and exploited for manufacture process optimisation.