GENEVA: A team of Swiss adventurers are preparing their solar-powered plane for its first international flight next month.The Solar Impulse team says the flights to Belgium and France are a big challenge because the plane will need to navigate across international air traffic networks.The single-seater prototype with the wingspan of a Boeing 777 made its 2009 maiden flight in Switzerland and further tests have all taken place there.Pilot Andre Borschberg said Thursday the success of the first cross-border flights depends on the team receiving authorization from national authorities.The team says it will ready the plane from May 2 and take off to Brussels when weather conditions are right.The plane is expected at the 49th International Paris Air Show from June 20-26. – Yahoonews