Acrosoma® is a composite panel with a tri dimensional fibre structure. Acrosoma® panels have a very high buckling resistance and are therefore the perfect material for rotor blade spars. Acrosoma® panels can be used as Wind turbine rotor blade spars in one long piece. They have a constant quality. The cost and weight of Acrosoma® spars is half of spars made in standard sandwich panels. Composittrailer shows a spar demonstrator and extensive test results.