Solar Impulse Completes First Zero-Fuel Intercontinental Roundtrip Flight
July 24, 2012

Solar Impulse Completes First Zero-Fuel Intercontinental Roundtrip Flight

Lawrence LeBlond for - Your Universe Online

It has been quite a journey for two Swiss visionaries, one a Businessman who trained as a pilot in the Swiss air force and flew missions for 20 years and the other a psychiatrist who became the first person to fly around the world in a hot air balloon; the pair today completed the first ever intercontinental roundtrip flight using only the power of the Sun.

Psychiatrist Bertrand Piccard and businessman Andre Borschberg first set their sights high in December 2009, when the Solar Impulse project made its first ever test flight. Since then it has been all up hill for the duo, culminating with a successful landing in Payerne, Switzerland, completing a solar-powered flight that took them more than 1,800 miles to Ouarzazate, Morocco and back again, totaling close to 3,700 miles in all, on zero fuel.

The HB-SIA prototype, with Piccard at the helm, took off at 7:01 a.m. today (July 24) from Toulouse, France and landed in Payerne at about 8:03 p.m. this evening. Piccard and Borschberg took turns in the single-seat cockpit during the 2-month long journey, making a total of 8 flights (6 were scheduled)

The most challenging legs of the journey were the flights between Rabat and Ouarzazate, Morocco, with often turbulent weather conditions throughout the hot, arid region, forcing the team to turn around on their initial flight from Rabat to Ouarzazate and reschedule for a later date.

The team also had to postpone a few flights and on the last leg of the return trip home, the team had to make last minute decisions to fly to Toulouse before heading on home to Payerne, due to inclement weather and strong head winds.

The HB-SIA prototype has a wingspan of about 208 feet (about the size of an Airbus A340) and a weight equivalent to that of a midsize car. It is the largest aircraft in relation to its weight/dimension ratio ever built. It has 12,000 solar cells that power four electric motors with a maximum power of 10CV each. Renewable energy charges the 400kg polymer batteries during the day, enabling the airplane to fly through the night.

The Solar Impulse team, which began their Crossing Frontiers 2012 project on May 24, 2012, have proven the reliability of the plane´s technology and the efficiency of its energy consumption. Often remaining in holding patterns above landing strips for hours awaiting for thermals to settle down, the plane almost always reached its target with full batteries.

Originally built only to prove that it is possible to fly night and day, which was shown in a 2010 flight lasting 26 hours, the HB-SIA prototype is now in the process of setting world records for solar aircrafts, becoming the first documented and verified by the International Air Sports Federation (FAI), in straight distance, free distance and distance along a course.

“It´s been an extraordinary adventure not only for what we´ve achieved with this airplane, originally only designed to demonstrate the possibility of flying day and night with a purely solar energy, but  also for what has resulted in a tightly fused team, confident in the project and in their capacity to make it happen,” said  Borschberg, CEO of Solar Impulse, during a press conference following the successful end of the journey.

“I am proud what we´ve been able to accomplish together, all of us, from the engineers that have built a fantastic airplane, to the Mission team experts that found a safe but successful strategy to the ground crew who had to operate in challenging conditions and multimedia team who under any circumstance brought the message of the project to the public,” he added. “The world´s first intercontinental solar-powered flight would have never happened without the fantastic support provided by all people that crossed HB-SIA´s way.”

“The success of this mission was not only aeronautical: it also stands in the quantity of positive emotions we managed to bring to the cause of renewable energies,” said Bertrand Piccard, Initiator and Chairman of the Solar Impulse Program, as the ground crew opened the canopy.

“Solar Impulse has demonstrated that a solar-powered airplane can fly day and night using no fuel. The next challenge is to fly around the world. Our aim is to prove that progress is possible using clean forms of energy. Becoming a pioneer is all in the mind,” reads a statement on the Solar Impulse website.

The Solar Impulse project is supported, among others, by Solvay, Omega, Deutsche Bank, Schindler, Bayer Material Science and Altran; EPFL (Lausanne Federal Institute of Technology) as Official Scientific Consultant and Dassault-Aviation as Aviation Consultant.

Follow the Crossing Frontiers 2012 Solar Impulse journey on redOrbit.