Radial tire with crown reinforcement including radial ply

A tire with a radial carcass reinforcement of maximum axial width S0, the tire comprising a crown reinforcement formed of at least two working crown plies of inextensible reinforcement elements, crossed from one ply to the other, forming angles of between 10° and 45° with the circumferential direction, said plies having axial widths at least equal to 80% of the width S0, and greater by at least 16% of the width S0 than the width of an additional ply of reinforcement elements, arranged radially between said working plies, said working plies being, on either side of the equatorial plane and in the immediate axial extension of the additional ply, coupled over an axial distance at least equal to 3.5% of the width S0, then being decoupled by profiled members of rubber mix at least over the remainder of the width common to said two working plies, the tire characterized in that the reinforcement elements of the additional ply are metallic, inextensible and substantially radial.