Solar impulse 2

Piccard and Borschberg have been working on projects to show how their technology can be used in other applications

Swiss project director Bertrand Piccard was in the cockpit during the 2,763 kilometre (1,716 mile) flight from Cairo

Solar Impulse 2 is due to land at Al-Bateen Executive Airport in Abu Dhabi where it launched its tour on March 9, 2015

'It's a project for energy, for a better world' Piccard, 58, told journalists before taking off

The final leg of the world tour was postponed due to the pilot's health

After the two-day flight from Spain, just one final leg lies between it and its final destination, Abu Dhabi

The voyage marks the first solo transatlantic crossing powered only by sunlight

The plane is powered in the night sky by the energy stored in its 17,000 photovoltaic cells

The voyage marks the first solo transatlantic crossing in a solar-powered airplane, expected to last four days

The flight is expected to take 90 hours before landing at Seville airport.

Cameras in a boat in NY harbor captured the innovative solar powered aircraft as it flew over the Verrazano Bridge

From New York they will attempt to cross the Atlantic to Europe and on to the Middle East

The flight to the Lehigh Valley International Airport is expected to take 17 hours, organizers say

"Amazing to have landed in #Dayton after being in the sky for 17 hours!" Borschberg tweeted

The experimental solar-powered plane was piloted by Swiss adventurer Bertrand Piccard

'The Pacific is done, my friend. I love it, but it's done' says clearly relieved Swiss adventurer Bertrand Piccard

Solar Impulse 2 resumes its record-breaking quest to circle the globe without consuming a drop of fuel