ESDU AERO 00.01.11 introduces a large Mollier chart available separately that gives curves of speed of sound, pressure, density, temperature and real gas factor as functions of specific enthalpy and entropy. It is assumed the air is in dissociation equilibrium and that the perfect gas laws apply to each components. Except for the data for the speed of sound the curves are plotted for a mixture of nitrogen and oxygen; the speed of sound data relate to a nitrogen/oxygen mixture with one per cent of argon. It is commented that the omission of the other gas components has been shown to have a negligible effect as has the inclusion of the argon for the speed of sound data. For temperatures below 2000 K, ESDU AERO 00.01.12 should be consulted and worked examples illustrating the use of the charts are in ESDU AERO S.00.03.27.