On 9th March, a plane took off from Abu Dhabi. Not an uncommon sight in UAE but this time was different – the plane was completely powered by energy from the sun. Solar Impulse 2 is a Swiss-led project and the brainchild of Bertrand Piccard who hopes it will be the first solar powered plane to fly around the world.
Solar Impulse 2’s journey started in Abu Dhabi and will be completed in multiple legs with 12 stops planned in places including China, Hawaii and New York. André Borschberg, a Swiss fighter pilot, and Bertrand Piccard, a psychiatrist and balloonist, are the two pilots who will alternate when flying each leg of the journey. The flight will finish in Abu Dhabi with the stops between the east coast of the US and UAE being dependent upon the weather.
During the day, the plane will fly at 28,000ft and drop down to 5,000ft at night, using its reserves of solar power built up during the day. It is predicted the trip will take five months to cover the 22,000 miles around the globe and the plane will spend a total of 500 hours in the air. The longest leg will be over the Pacific Ocean as the plane flies from China to Hawaii, a trip that will involve continuous flying for five days and nights over a distance of 5,270 miles. The sea legs of the flight will be the most challenging because if the plane loses power over the water, the pilots will have no other options but to await rescue by boat.
The first 912 mile leg between Abu Dhabi and Ahmedabad was completed by Borschberg in just over 13 hours and has already set a new world record as the longest point-to-point flight by a solar powered plane. However, the flight path of the plane is extremely weather dependent and, after completing the first leg of its flight, has been delayed in its departure from Ahmedabad in India due to a forecast of heavy rains.
The Solar Impulse prototype first flew in late 2009 and has demonstrated its abilities on many occasions. It flew its first international flight between Belgium and France in 2011, its first intercontinental flight from Spain to Morocco in 2012 and in 2013, it flew from California to New York in its first coast to coast flight of the US. Since then, the Solar Impulse prototype has been continuously redesigned and updated, culminating in Solar Impulse 2; a next generation design.
The plane itself is a real feat of engineering. It is driven by four electric propeller motors which are powered by 17,000 solar panels on the top surface of the plane and at 72 metres, the wingspan is greater than that of a Boeing 747 jumbo jet. The body of the plane is constructed predominantly from carbon fibre meaning it is extremely light for a plane of this size, weighing in at just 2,300kg. Ithas a maximum speed of 87mph, a cruise speed of 56mph and flies at just less than 40mph at night to conserve electricity stored in its lithium-ion batteries.
The Solar Impulse project is not aiming to revolutionise the air travel or aircraft design industries by proving a solar powered plane can work. It is hoped that this flight around the world will show the potential of renewable energies as society clings to non-renewables, reluctant to move away from them. The project is ultimately aspirational, showing that unlike Icarus; its wings will not melt the closer it flies to the sun but will in fact carry the plane even higher.
Images: Communicaciones, Solar Impulse