What does ISA stand for in aviation?

In aviation, ISA stands for International Standard Atmosphere. This is a model that represents a standard set of atmospheric conditions used primarily for calibrating aircraft instruments and for aircraft performance calculations. The International Standard Atmosphere provides a common reference point, which simplifies the comparison of performance data from different aircraft and allows for accurate flight planning and analysis.

The ISA establishes specific values for temperature, pressure, and density at various altitudes, creating a standardized environment for aviation operations. Understanding ISA is critical for pilots and operators, as it helps them account for variations in air density that affect lift, engine performance, and fuel consumption. Having a standardized atmosphere also aids in ensuring safety and efficiency in flight operations, as various aviation systems rely on those baseline values.