Operation experience with pneumomechanical spinning machines of BA type as well as spindleless spinning by producing yarn from the mixture of low grade cotton and waste proved that some changes in semifinished product (sliver) preparation technology should be carried out. Vibrous fabrics non-uniformity is one of negative definers of textile industry effiency and phisico-mechanic properties of the manufactured semifinished products. It causes the process instability and products defects. Modern technology for fibrous fabric aerodinamic building include factors which maintain high quality uniform material yielding: kind of fibrous raw material, fibres disengagement and uniform degree, taking-off assembly desing, formed air thickness, flow velocity and others. Proving the grounds for fibres behavior in forming the fabric is quite a complicated problem, but their knowledge is necessary for the process controlling and perfection, modernizing of existing and making new structural elements of methods for high quality semifinished products manufacturing. Study of fibrous layer forming by aerodinamic method was based on interaction of rotating removable roller which delivers the discrete fibre flow to the rectandular chamberduct, on the one hand, and the condensor on its opposite side, where flat fibrous layer is formed by action of a fan, on the other.