Solar Impulse said the flight reached an altitude of 5,500 feet (1,676 meters). After landing, Scherdel emerged from the cockpit with his arms raised and the team broke open bottles of champagne.
"It went so silent, so soft," Piccard said.
He acknowledged the role of good weather, however.
Because the solar panels are needed for day flying and for charging the 400-kilogram (882-pound) lithium batteries that power the plane by night, it relies on sunshine, and Piccard said his team will have to scrupulously monitor conditions and divert routes to avoid storms.
Personnel on the ground will also have to be able to keep up with the plane as it follows the best weather to provide service at each stop, he said.
"Round-the-world will seem impossible until we do it." Piccard said. "Today is an absolutely incredible milestone."
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