Equivalent airspeed (Veas) = Vtas * √σ (SI Unit is m/s)

Vtas – True airspeed in m/s

Veas – Equivalent airspeed in m/s

σ – Density ratio{Ratio of density at an altitude to the sea level density} (no unit)

σ = ρ/ρ0

Equivalent airspeed (Veas) is defined as the calibrated airspeed corrected for the compressibility factor of air at a non – trivial Mach number. Also, defined as the product of true airspeed and square of the density ratio.

It is useful for predicting the aircraft handling, aerodynamic loads, stalling parameters etc…