We present the results of quasi-classical trajectory (QCT) calculations for the N(S-4) + O-2 reaction over a broad range of collision energies with scaled ab initio potential energy surfaces of the (2)A' and (4)A' electronic states. The analysis of product rovibrational distributions support the suggestion that this reaction is a source of highly excited NO in the upper atmosphere, The computed NO vibrational distribution is found to be in good agreement with a recent measurement.