How do you calculate Vref for an aircraft?

To determine Vref for an aircraft, it is most commonly calculated by multiplying Vso, the stall speed in landing configuration, by an appropriate factor that accounts for safe approach and landing speeds. The convention is to use 1.3 times Vso for calculating Vref. This adjustment ensures that Vref provides a safety margin above the stall speed, accommodating for potential fluctuations in airspeed and ensuring a more stable approach and landing.

Using this method of multiplying Vso by 1.3 establishes a reliable reference speed that aids pilots in executing safe landings, particularly during the final stages of approach. This significant margin above the stall speed minimizes the risk of stalling during critical phases of flight. Other factors, such as weight and environmental conditions, can also influence the actual Vref used, which is essential for ensuring safe operation of the aircraft during landing.

The other approaches listed do not yield the standard or correct Vref calculation used in practice.