Tire having an H/S form ratio of <0.6

A tire comprising a radial carcass reinforcement (1) surmounted by a crown reinforcement (3) comprising at least two working crown plies (32, 34) of inextensible cables, crossed from one ply to the next, forming angles (α, β) of between 10° and 45° with the circumferential direction, said plies having widths L32, L34 at least equal to 80% of the maximum axial width S0 of the carcass reinforcement and including, firstly, between the carcass reinforcement and the working ply (32) radially closest to the axis of rotation, an axially continuous ply (31) formed of inextensible metal cables forming with the circumferential direction an angle δ of at least 60° and the axial width L31 of which is at least equal to the axial width L32, L34 of the narrowest working crown ply (32, 24), and including, secondly, between the two working crown plies, a first additional ply (33) formed of metallic elements oriented substantially parallel to the circumferential direction, the axial width L33 of said first additional ply being at least equal to 0.7 S0, and the modulus of elasticity upon traction of which is at most equal to the said modulus of the most extensible working ply (33, 34), characterized in that there is arranged, radially above the radially outermost working crown ply (34) and on either side of the tire, a second additional ply (36) formed of metallic elements oriented substantially parallel to the circumferential direction, of narrow width L36 substantially centered on the end of the first additional ply (33) such that the ends of said second additional ply are axially distant from each end of the first additional ply by at least 10 mm and such that said second additional ply radially covers the end of the first additional ply of circumferential cables which is arranged between the two working plies.