This article is the second part of a two-part manuscript addressing the DME/TACAN multipath impact on the future airborne GNSS L5/E5a receivers. Part I developed the analytical carrier-to-noise-ratio degradation model due to DME/TACAN considering multipath, in the presence of a temporal blanker. Part II introduces an air-ground channel model, that is wide band, geometry based and combines deterministic and statistical parts. The model includes an Okumura-Hata path loss for computing the scatterer illumination, an analytical formula for the additional delay and the mathematical expression of the scattered power. Given the very large number of illuminated scatterers to be considered for an Air-Ground scenario, a statistical simplification of the Physical Optics approach is introduced to simplify the derivation of the scattered powers. The propagation channel model and the mathematical model of the carrier-to-noise-ratio degradation are applied to two low-altitude operational hot-spots, JALTO (Pennsylvania, United-States) and TIXAK (Frankfurt, Germany). It is shown that only a few illuminated scatterers generate a scattered power above the blanking threshold and that the additional carrier-to-noise-ratio degradation generated by the DME/TACAN multipath only is smaller than 0.52 dB.