Abstract:

ESDU 77022 gives equations for calculating for altitudes up to 50 km in British Customary Units or SI Units the pressure and density in a Standard Atmosphere and the density in an Off-Standard Atmosphere whose temperature profile differs by a constant temperature from the Standard at all heights. Also given are equations, again in both sets of units, for calculating pressure height in a Standard Atmosphere, and the temperature difference from Standard and geopotential height in an Off-Standard Atmosphere, from a knowledge of pressure. Equations are given for the speed of sound and dynamic viscosity, and for the relationship between geometric and geopotential heights, and between pressure, pressure height and geopotential height. ESDU 68046 tabulates values of atmospheric properties in a Standard and Off-Standard Atmosphere while ESDU 72018 tabulates the properties in SI Units but for heights in feet, the most commonly used height unit in aircraft operations. ESDU 78012 gives equations for calculating the properties of non-standard atmospheres and their relationships to the Standard.