Aviation Dictionary

Equivalent airspeed

Airspeed equivalent to CAS in standard atmosphere at sea level. As the airspeed and pressure altitude increase, the CAS becomes higher than it should be, and a correction for compression must be subtracted from the CAS.

Dictionary Term

Equivalent airspeed

Definitions

Airspeed equivalent to CAS in standard atmosphere at sea level. As the airspeed and pressure altitude increase, the CAS becomes higher than it should be, and a correction for compression must be subtracted from the CAS.
Means the calibrated airspeed of an aircraft corrected for adiabatic compressible flow for the particular altitude. Equivalent airspeed is equal to calibrated airspeed in standard atmosphere at sea level.

References

14 C.F.R. Part 1, Federal Aviation Administration, 2026
Pilot's Handbook of Aeronautical Knowledge, Federal Aviation Administration, 2023