Solar Impulse crosses Gibraltar Strait

June 7, 2012

Flying around the world in an aircraft powered only by solar cells and batteries would surely qualify as a magnificent triumph of aviation technology. But as Bertrand Piccard and Andre Borschberg move toward that goal with an ungainly looking aircraft called the Solar Impulse, they assert a different goal: exploring the possibilities for clean, renewable energy including “the protection of nature without ecological fanaticism.”

In a lead-up to a planned 2014 circumnavigation of the globe, on June 6 Piccard landed the carbon-fiber Solar Impulse HB-SIA in Rabat, Morocco, after a 19-hour, 8-minute flight from Madrid, Spain, that covered 448 nautical miles, crossed the Strait of Gibraltar (at 22,616 feet), and registered an average groundspeed of 28 knots.

The aircraft, known for a wingspan equal to an Airbus A340’s but weighing about as much as a family auto, flew as high as 27,000 feet, according to information posted on the project’s website.

The HB-SIA is propelled by four electric engines each developing 10 horsepower. It had been in Madrid since arriving from Switzerland in late May, awaiting favorable weather for the Gibraltar crossing, news reports said.

The choice of Rabat as the destination for the first intercontinental flight of the aircraft put focus on Morocco’s development of solar energy to replace imported oil as a fuel source and for possible export. On landing, Piccard was greeted by officials of the Moroccan Agency for Solar Energy. A next planned flight leg for the Solar Impulse was to Ouarzazate, the future location of the first of five solar-energy plants Morocco plans to build.

The Solar Impulse team emphasizes the focus on clean energy, business ethics, and social responsibility in a message on its website. “By writing the next pages in aviation history with solar energy, and voyaging around the world without fuel or pollution, Solar Impulse's ambition is for the world of exploration and innovation to contribute to the cause of renewable energies, to demonstrate the importance of clean technologies for sustainable development; and to place dreams and emotions back at the heart of scientific adventure.”

A successor aircraft, designated the HB-SIB, will attempt the round-the-world flight. The aircraft’s batteries will charge during the day, allowing it to fly in a shallow descent at night while operating on battery power alone.

In March 2011, AOPA reported that the project had acquired sponsorship necessary to launch on the world-circling flight. In May 2011, the craft flew internationally from Switzerland to Brussels, Belgium, covering the 340 nautical miles in 13 hours.
Piccard, chairman of the Solar Impulse group, is a psychiatrist and aeronaut who made the first nonstop round-the-world balloon flight, with Brian Jones. Borschberg, the CEO, is an engineer, a graduate in management science, fighter pilot, and professional airplane and helicopter pilot.