ESDU Aero S.00.01.10 gives curves of the ratios of static pressure/stagnation pressure, static temperature/stagnation temperature, local velocity/speed of sound for stagnation conditions, local kinetic pressure/stagnation pressure, and local flow area/flow area for a Mach number of unity. All the curves are plotted against Mach number for various values of the ratio of stagnation temperature/characteristic vibrational temperature; values of the characteristic vibrational temperature are given for some common gases together with the range of temperature for which they are valid. It is recommended that outside the given temperature range the equations from which the curves were derived, which are also given, should be used, except for the pressure and temperature ratios for which the error in using the curves is negligible. The use of the equations requires accurate values of the ratio of specific heat capacity at constant pressure to that at constant volume for both for ambient and stagnation conditions which may be obtained from ESDU Aero 00.01.08. The worked example illustrating the use of the data applies to such a case and shows the errors that would be involved. Equations are also given for the ratio of specific heat capacities and for specific heat capacity at constant pressure, also in terms of the characteristic vibrational temperature.