How to use this calculator
- Enter Vso. Use the landing-configuration stall speed.
- Set reference factor. Use the factor appropriate for the aircraft or training check.
- Enter wind and gust. Use steady and gust speeds from the same report.
- Read target speed. Use the result only as a screening calculation.
How it works
Base speed is factor x Vso. Gust additive is (gust - steady wind) / 2 when gust exceeds steady wind.
Use it with stall speed by weight, crosswind component and descent planning.
Worked example
Verified against the live calculator
With Vso 45 kt, factor 1.3, wind 10 kt and gust 18 kt, base Vref is 58.5 kt and the target with gust additive is 62.5 kt.
Frequently asked questions
How is base Vref estimated?
The calculator multiplies landing stall speed by the entered reference factor, commonly 1.3 for simple training arithmetic.
How is gust additive calculated?
It adds half the difference between gust speed and steady wind speed.
Should I always use this target speed?
No. Aircraft manuals, operator procedures and runway conditions control actual approach speeds.
Does this include runway length or landing distance?
No. It only computes a speed target; landing distance and performance require approved data.
Method & assumptions
- Uses simple Vso factor and half-gust-spread arithmetic.
- Does not replace POH/AFM speeds, flap schedules, runway performance, aircraft category, operator policy or stabilized-approach criteria.