Choosing what to calculate

Solve for heading and groundspeed, wind direction and speed, required heading and true airspeed, or resulting track and groundspeed. Touch the corresponding button on the row above the tab bar. The selected button will show a green border, the values to be calculated will have a green frame around their header, and their thumbwheels will be greyed-out and disabled.

Aircraft display

The center area of the screen resembles a Horizontal Situation Indicator. It shows an aircraft symbol, a track bar (in green), and a wind direction arrow (in cyan). True and magnetic north are also shown, as a white star and a magenta half-arrow respectively. These provide a visual representation of the values that are displayed.

Crosswind and headwind components are shown numerically, in knots, underneath the aircraft symbol.

The aircraft display can be shown with the heading up, track up, or north up (magnetic or true). Tap the aircraft symbol to cycle through these options.

Groundspeed, distance and time

You may “lock” either the distance or the time, by tapping on the cyan frame around either. For any groundspeed changes, the locked value will remain the same, while the “unlocked” value will be recalculated for the new groundspeed.

If solving for wind, or for heading and true airspeed, you can change the groundspeed by dialing it in directly. You can also enter groundspeed by dialing in distance and time. If a cyan frame is shown around groundspeed, it can be locked. If locked, changing distance will update time, and vice-versa.

On smaller devices, distance and time columns are out of view, but can be displayed, and hidden again, by tapping the arrow button at the right edge of the screen. The aircraft symbol will disappear to make room for the extra columns. Please note that while distance and time are shown, magnetic variation cannot be modified.


Speeds are shown simultaneously in knots, kilometres per hour, metres per second, and miles per hour. For TAS and groundspeed, speed is also shown in seconds per nautical mile.

For wind speed, units displayed include knots, km/h, meters per second and feet per minute.

Vertical Speeds

It is sometimes of interest to convert among different vertical speeds (not related to wind, but for example to climb or descent rates). Units shown below wind speed allow quick conversion of meters per second to feet per minute.

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