International Standard Atmosphere

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The International Standard Atmosphere is a tabulation with altitude of the standard variation of pressure, temperature, density, viscosity, etc, appropriate to mid latitudes, released by the ICAO. The International Standard Atmosphere (ISA) is also sometimes used as a synonym for Standard conditions for temperature and pressure.

Various tabulations of the 1976 standard may be found on the web, e.g. at [1], or, of an earlier but similar standard, in publications such as Appendix 1 of Batchelor. The latter tabulation gives at sea level a pressure of 1.013 bar and a temperature of 15 C, and an initial lapse rate of 6.5K/km. Above 12km the tabulated temperature is essentially constant. The tabulation continues to 18km where the pressure has fallen to 0.075 bar and the temperature to -56.5 C.

[edit] See also

• Atmospheric models
• US Standard Atmosphere
• Standard conditions for temperature and pressure

[edit] References

• Batchelor, G. K., An Introduction to Fluid Dynamics, Cambridge Univ. Press, 1967.
• Tabulation of 1976 standard at University of Sydney aeronautical mechanics site
• ICAO, Manual of the ICAO Standard Atmosphere (extended to 80 kilometres (262 500 feet)), Doc 7488-CD, Third Edition, 1993, ISBN 92-9194-004-6.

[edit] External link

• ICAO