Fan blade or vane with cross-shaped or star-shaped composite root

A method for manufacturing a turboprop engine blade or propeller airfoil made of composite material comprising a fiber reinforcement densified by a matrix, the method comprising:

• producing by three-dimensional weaving of a fiber blank made as a single piece, the fiber blank having a flat shape extending along a longitudinal direction and a transverse direction respectively corresponding to a span direction and to a chord direction of the blade or propeller airfoil to be manufactured, the fiber blank comprising a root part and an aerodynamic profile part extending along the longitudinal direction from the root part and along the transverse direction between a leading edge portion and a trailing edge portion,
• shaping of the fiber blank to obtain a fiber preform as a single piece having said aerodynamic profile part forming an aerodynamic profile preform part and said root part forming a root preform part, and
• densifying the fiber preform by a matrix to obtain the blade or propeller airfoil made of composite material having a fiber reinforcement consisting of the fiber preform and densified by the matrix, and forming a single piece with an integrated root,
• wherein the root part of the fiber blank comprises several non-interlinkings extending along a plane parallel to a surface of the fiber blank, each non-interlinking extends in the transverse direction from an edge of the root part of the fiber blank and over a distance less than half the width of the root part, each non-interlinking separating two woven portions in the fiber blank and wherein the shaping of the fiber blank comprises orientation in different directions of the two woven portions separated by the non-interlinkings in such a way as to form the root preform part including a plurality of branches.