Niklaus Gerber, an air traffic control expert who's helping to plan the plane's routes, said during an interview live-streamed on the Solar Impulse 2 website, that the New York trip will be challenging. The Solar Impulse 2's wings, which stretch wider than those of a Boeing 747, are equipped with 17,000 solar cells that power propellers and charge batteries. The crew was forced to stay in Oahu, Hawaii, for nine months after the plane's battery system sustained heat damage on its…