Polyamid carcass ply with two moduli of elasticity in a pneumatic tire

A pneumatic tire having a single carcass ply (12) and a belt structure (24) disposed radially outward of the single carcass ply (12) in a crown portion of the tire (10) is disclosed. The carcass ply (12) comprises at least one composite cord (30) comprising three aramid first yarns (34) twisted helically about one nylon second yarn (32), the first yarns (34) having a modulus of elasticity greater than the modulus of elasticity of the second yarn (32).