International Standard Atmosphere(ISA)

Definition

A model atmosphere used for aircraft performance calculations. At sea level: 15 degrees C, 29.92 inHg, and temperature decreases at 2 degrees C per 1000 feet. ISA deviation affects aircraft performance.

Related Terms

Density Altitude

Pressure altitude corrected for non-standard temperature. It represents the alti...

Pressure Altitude

The indicated altitude when the altimeter is set to 29.92 inHg (1013.25 hPa). Us...

Temperature Lapse Rate

The rate at which air temperature decreases with altitude. The standard lapse ra...

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