Glider instructor and forecaster at Météo France, the author has always sought to understand the atmospheric movements that allow non-motorized aircraft to stay aloft. He was also interested in the particular weather situations favorable to long distance flights: 800 to 1000 km in glider and 200 to 300 km in paraglider.

He understood that the great gliding flights are linked to characteristic and homogeneous air masses which depend on a well defined general altitude current.

In collaboration with pilots from regional gliding centers and through flight stories, he conducted a long study on the weather conditions encountered and on the analysis of air masses. This collaboration was then extended to paraglider pilots. By participating in various regional, national and international flying championships ? The author has refined his experience in the field of the very low layers of the atmosphere.

Moreover, by intervening in training sessions on aerological forecasting with glider, paraglider and microlight pilots, he has developed a method of analysis for free flight enthusiasts. It was natural for the author to synthesize all this data and accumulated knowledge and to share his methodology through this book. By reading this book, free flight pilots will be able to more easily analyze and interpret the weather documents they consult on Internet sites. Thus, they will be able to determine 2 or 3 days in advance, the most favorable situations for flights.