An Idea born in Switzerland
In 2015 started the attempt of the First Round-The-World Solar Flight, from Abu Dhabi to Hawaii, already achieving the longest solo solar flight ever achieved in aviation history. In 2016, Bertrand Piccard and André Borschberg, our two Pilots and Founders, completed the first circumnavigation of the globe with no fuel. With their solar aircraft, a flying laboratory full of clean technologies, they flew 40,000 km to promote the use of renewable energies and energy efficiency on the ground, for a better quality of life. Across the Round-The-World flight, the team overcame technical, human and operational challenges that had never been faced before.
Route
After the 8 world records set by the Solar Impulse prototype, when it became the first solar airplane ever to fly through the night, between two continents, and across the United States, Bertrand Piccard and André Borschberg accomplished the ultimate phase of the adventure: the 2015-2016 First Round-The-World Solar Flight.
40,000 km from Abu Dhabi, our departure and arrival Host City, to India, Myanmar, China, Japan, U.S.A and back to Europe and Abu Dhabi. As with all great firsts, there were no benchmarks. Strategies had to be invented from scratch to allow Solar Impulse 2 to fly across the Pacific for 5 consecutive days and nights, and become the first solar airplane to accomplish an oceanic crossing. This historic and record-breaking flight from Japan to Hawaii was achieved by André Borschberg in July 2015, proving that clean technologies can accomplish incredible things. Bertrand Piccard then finished crossing the Pacific, and flew over the Atlantic, making Si2 furthermore the first solar plane to have crossed the world’s two biggest oceans.
Read more2 years around the world to achieve 40 000km without a drop of fuel is an aviation first as well as a first for energy. Discover the wrap up of the mission, the key moments and outcomes
Read more about the mission's key numbersRecord breaking
An historic aviation first as well as a premiere for renewable energies and clean technologies. Bertrand Piccard’s vision of an airplane of perpetual endurance, able to fly day and night without fuel is now realized. André Borschberg, leaving Nagoya and landing in Hawaii 5 days and nights later, proved we can achieve incredible things with clean technologies.
Landing on July 3rd 2015 after 117hours and 52minutes, André Borschberg’s flight from Japan to Hawaii marks the completion of 13 years of pioneering research and development. Bertrand Piccard’s vision, coupled with André Borschberg’s entrepreneurial mindset, and the skills of a multi-disciplinary team, have enabled an idea to become a reality. And this even though no aviation specialist, apart from Dassault, believed it could be possible: “Too big, too light and impossible to control in flight”, they all said.
Read more about the flight...Zero-fuel aircraft
Solar Impulse is not the first solar airplane, but it is the first to fly day and night, without any fuel, only using energy stored in its batteries. It is also the first to have crossed oceans: 5 days and nights from Nagoya, Japan, to Kalaeloa, Hawaii; 3 days and 2 nights from Kalaeloa to San Francisco; and 3 days and nights from New York to Seville, Spain. Behind Solar Impulse’s achievements, there is always the same goal: show that if an airplane can fly several days and nights in a row with no fuel, then clean technologies can be used on the ground to reduce our energy consumption, and create profit and jobs.
The plane’s unusual look undoubtedly helped the message of the project to be spread worldwide. The wingspan of a Boeing 747 Jumbo Jet, the weight of a family car, the power of a small motorcycle, Solar Impulse 2 is the largest aircraft ever built with such a low weight.
« To build an airplane of the size of a 747 with the weight of a car, something which was considered impossible by the aviation industry, we had to develop the right mindset in order to push the limits of the technologies. With Partners who believed in the same vision we developed solutions to make our airplanes very energy efficient. All these technologies can be used today in other applications to make our world more energy efficient as well. »
André Borscherg
Technical challenges
Solar Impulse 2 was built to take up the challenge of achieving the first round-the-world solar flight. This revolutionary airplane had to do what no one had ever done before: fly through several consecutive days and nights to cross oceans without using any fuel. André Borschberg achieved such an oceanic crossing during his record-breaking flight from Nagoya to Hawaii.
Our challenge: to take an airplane to such a high level of energy efficiency that it could fly day and night relying only on the sun. This required the optimization of new kinds of technology and a drastic reduction in energy consumption. The components normally used in aircraft construction were far too heavy for Solar Impulse.
Solar Impulse’s 80 engineers and technicians, under André Borschberg’s leadership, thus had to find highly innovative solutions. What major civil and military aircraft makers thought impossible was achieved by the ingenuity of a small team.
« Imagine energy reserves increasing during flight! To make this dream a reality, we had to make maximum use of every single watt supplied by the sun, and store it in our batteries. We tracked down every possible source of energy efficiency. »
André Borschberg
Human challenges
The long flights of this adventure represented a challenge of endurance and vigilance for a single pilot in an unheated and unpressurized 3.8m3 cockpit.
Crossing the Pacific and Atlantic oceans introduced a new kind of difficulty for our pilots Bertrand Piccard and André Borschberg. The Round-The-World Solar Flight represented approximately a 40,000km journey. Although achieved in several legs, Bertrand Piccard and André Borschberg cumulated around 500 flight hours in the tiny cockpit.
The pilot had to have exceptional stamina to control this plane which is sensitive to turbulence due to its broad wings and light weight.
« What is really special, is that it is the first and only airplane in the world which has unlimited endurance. We have an airplane which is fully sustainable in terms of energy, and our challenge now is to make the pilot sustainable as well. »
André Borschberg
Flight strategies
Even though the pilot was on his own in the plane, he was not alone. He was in contact by satellite with the Monaco Mission Control Center (MCC), where the team monitored the route and managed performance and energy. Weathermen, mathematicians, air traffic controllers, planning engineers, flight director ... all gathered to predict all possible scenarios and prepare a flight strategy.
« The MCC is an essential link for the success of Solar Impulse's round-the-world tour. This is where the decisions are made for the departure and routes of each stage. It is via the MCC that the pilot is in contact with the whole world. »
André Borschberg
« The Mission Control Center is the nerve center of the the project. It is where all the information from the plane, takeoff and landing sites is gathered and shared with the world, to allow everyone to follow our adventure and understand our message about clean technologies. The fact that Monaco has been selected results from a long established friendship with Prince Albert II who, in addition to being a patron of Solar Impulse, is one of the only Heads of State to champion environmental protection at all political discussions. »
Bertrand Piccard
Operational challenges
Landing on the biggest international airports with an experimental aircraft, no hangar big enough to house the aircraft... not a problem for the ground crew. The men and women behind the scene made it possible for Si2 and its pilot to go around in a safe and secured way, organizing aircraft safety, movements, technical tests and check-up in coordination with the mission engineers at the MCC.
« The ground crew is a team of about 20 members dealing with a lot of things, mainly the handling on the aircraft from the hangar to takeooff, and at landings until the aircraft is safe into a hangar or its mobile hangar. Add a lot of uncertainties on international airports and you can be sure the team has a lot of challenges! But it is also an immense pleasure to be at the forefront. »
Nils Ryser, Head of Ground Crew
History
Solar Impulse is not the first solar airplane ever designed, but it is certainly the most ambitious. None of its predecessors has ever managed to fly right through the night with a pilot on board.
Solar aviation began with model aircrafts in the 1970s, when affordable solar cells appeared on the market. But it was not until 1980 that the first human flights were accomplished.
« Solar Impulse was not built to carry passengers, but to carry messages. We want to demonstrate the importance of the pioneering spirit, to encourage people to question what they’ve always taken for granted. The world need to find new ways of improving the quality of life. Clean technologies and renewable forms of energy are part of the solution. »
Bertrand Piccard