Controls and tests :
"Le Ville", wind-tunnel tested by the Aerotechnical Institute of St-Cyr, has resisted against a back-wind of 120 km/h and a front-wind of 54 km/h. These tests have proven its high resistance and a 0.54 CX.

With 7 umbrellas, Serge Negri has gone 15 km at 40 km/h on the Quebec great frozen lake without any damage!
The TV cameras (TF1 et Canal+) were there.

Closer to Cherbourg on the Sciotot beach, the umbrellas have turned into parascending parachutes !