The solar powered plane, Solar Impulse, left the United States on Monday 20 June to fly across the Atlantic as part of its historic attempt to circle the globe.
The experimental single seat plane left New York's John F. Kennedy International Airport at about 2:30 a.m local time, and is expected to take between 90 and 110 hours to reach Seville Airport, Spain.
The Swiss team are flying the aircraft to raise awareness and build support for clean energy technologies. The team are hoping Solar Impulse will eventually complete its route in Abu Dhabi, where the journey began in March 2015.
Andre Borschberg alternates with fellow pilot Betrand Piccard at the controls for each segment. But because the craft's cruising speed is the same as a car and journeys are longer, both pilots had to take up meditation and undergo hypnosis in training so they could stay alert for longer periods, and they alternate taking naps.
The carbon-fibre plane has a bigger wingspan than a Boeing 747, where it collects solar energy from more than 17,000 solar cells. It doesn't require a single drop of fuel, even for long distance journeys. It was supposed to take off on Sunday 19 June but bad weather delayed the flight.