Abstract: A radome constructed using a rigid or semi-rigid foam core and sandwich construction is described. The foam core radome virtually eliminates water absorption problems associated with present technology radomes. The radome also provides greater impact strength and consistent, high radar transparency without sacrificing weight and structural stability, thereby providing a much longer service life in moisture/impact critical environments. Preferably, the radome includes a vinyl rigid closed-cell foam core consisting of a polymeric alloy of a cross-linked aromatic polyamide urea and a linear vinyl polymer.