Complex sentence: European eXPErimental Re-entry Test-bed (EXPERT) is an ESA aerothermodynamics research programme and vehicle that will be launched on a Russian Volna launch system and will provide knowledge and experience in the design and development of re-entry vehicles.
Split into simpler sentences: European eXPErimental Re-entry Test-bed (EXPERT) is an ESA aerothermodynamics research programme. It was planned that vehicle will be launched on a Russian Volna launch system and will provide knowledge and experience in the design and development of re-entry vehicles.