Solar Impulse crossed from Toulouse, France to Payerne, Switzerland on July 25, completing an epic intercontinental voyage for the giant solar-powered craft. Its itinerary consisted of a flight from the Solar Impulse home base in Payerne, Switzerland to Madrid, Spain, followed by a jump across the Strait of Gibraltar, for the first time linking Europe and Africa by solar flight. Because of its light wing loading, the airplane is subject to the vagaries of wind and turbulence as the ultralight aircraft it truly is, and was forced to turn back after battling the elements for half a day on its attempt to fly from Rabat, Morocco to Quarzazate, the site of the Moroccan solar agency’s huge desert solar generating site. A second try met with success, although punishing turbulence caused Andre Borschberg to wait for a night landing when the air was relatively cooler and calmer. Returning to Rabat, HB-SIA was subject to maintenance and inspections before its return flight to …