Detailed numerical calculations of electron transport coefficients and vibrational excitation rates in a He:N2:CO2gas laser discharge have been carried out over a range 1×10−16≤E/N≤5×10−16V cm2for several gas mixtures. Comparison of the results indicate that the vibrational excitation processes in the CO2molecule scale with the average electron energy and are approximately invariant with respect to gas mixture. At a fixed value of electron energy, the dominant effect of gas mixture variation is to modify the vibrational excitation rate into the nitrogen. The effect of gas mixture variation on electron drift velocity is greatest in CO2&sngbnd;He mixtures, but is substantially reduced when a small fraction of N2is added.