During the last six months, I have cooperated with the hot air balloon club Ballongveteranerna to create an electronic solution to measuring winds at low altitudes, called Windsond. The development is sponsored by the Swedish Airsport Federation. Wind conditions are of paramount importance for hot air ballooning, where the balloon drifts with the wind. The only means of flight path control lies in choosing the altitude. Interestingly enough, the wind direction and speed can differ a great...