Ground Speed Calculator
Find ground speed from true airspeed, course and wind using the wind triangle.
Flight Speed and Distance
Flight Speed and Distance
Calculators and guides for the speeds an aircraft has at the same moment: indicated, calibrated, true and ground speed, plus Mach number, great-circle distance and time en route. Each one shows how one speed becomes the next and which inputs it needs.
Calculators
True Airspeed Calculator
Convert calibrated airspeed to true airspeed from pressure altitude and outside air temperature.
Flight Speed and Distance
Indicated Airspeed Conversion Calculator
Step from indicated airspeed to calibrated, equivalent and true airspeed with your own position-error correction.
Flight Speed and Distance
Mach Number Calculator
Divide true airspeed by the local speed of sound to get Mach number.
Flight Speed and Distance
Flight Distance Calculator
Great-circle distance and initial true course between two latitude and longitude points.
Flight Speed and Distance
Flight Time Calculator
Time en route from distance and ground speed, in hours and minutes.
Flight Speed and Distance
Guides
Flight Speed and Distance
How Airspeed Changes With Altitude
Hold one calibrated airspeed in a climb and true airspeed and Mach number both rise. A table for 200 kt in the standard atmosphere shows by how much.
Flight Speed and Distance
Understanding Mach Number
Mach number is true airspeed divided by the local speed of sound. See why temperature alone sets that speed and how one airspeed gives two Mach numbers.
Flight Speed and Distance
How Pilots Calculate Flight Time
Flight time is distance divided by ground speed. See how to convert decimal hours, why headwinds cost more than tailwinds return, and how to work leg by leg.
Flight Speed and Distance
True Airspeed vs Indicated Airspeed
Indicated, calibrated, equivalent and true airspeed are links in one chain of corrections. Learn what each one means and how one becomes the next.
Flight Speed and Distance
Understanding Ground Speed in Aviation
Ground speed is true airspeed and wind added as vectors. See the wind triangle formula, a worked example and why a pure crosswind still slows you down.