Use this calculator for flight-planning study or a first-pass cross-check when all inputs describe the same aircraft, atmospheric condition, and phase of flight.

Reference stall speed (kt)

Reference stall speed of the aircraft.

Compute the clean-configuration stall speed as 1.15 times the reference stall speed. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

VS1 (kt)

Clean-configuration stall speed.

• Do not use a generic calculator in place of the current aircraft flight manual, approved performance data, operating limitations, NOTAMs, weather, or regulations. Real performance changes with configuration, runway condition, altitude, temperature, wind, loading, and technique.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Cross-check the result against the aircraft flight manual or approved planning system, then apply the required safety margins. Keep signed wind, heading, altitude, speed, and fuel conventions explicit.

• VS0 Speed Calculator

  Estimated landing-configuration stall speed from clean stall speed.

• VFE Speed Calculator

  Compute the maximum flap extension speed as 1.6 times the stall speed.

• VLE Speed Calculator

  Compute the maximum landing gear extended speed as 1.8 times the stall speed.