Forget the discouraging climate talks in Copenhagen and the difficulties in replacing fossil fuels with biofuel on airplanes. In Zurich, about 75 engineers and technicians have spent the past six years pursuing the dream of zero emissions by building a plane solely fuelled by solar power.
The prototype of the propeller driven airplane, HB-SIA, completed its runway test at Dubendorf Airfield, a military airport in Zurich, earlier this month.
Although the plane only flew about 350 metres at an altitude of one metre, the engineers and technicians appeared gleeful when it landed gracefully on the centre of the runway. Bertrand Piccard, the chairman of Solar Impulse and co-founder of the privately funded project, raced to embrace the pilot.
The short flight was a milestone for the project. The next test flight will take place in spring, between Dubendorf and Payeren, another military airport in Switzerland, to find out more about the airplane’s flying capabilities. A second HB-SIA is scheduled to fly around the globe in five legs as early as 2012.
Piccard, a Lausanne-born aeronaut, first came up with the idea of flying a solar-powered plane in 2003. He says people told him it was an insane idea. He was unable to find any funding for this €70 million (HK$782.8 million) project during the first year he pitched it.
But the spirit of adventure runs in the family. Piccard’s grandfather, a pioneer balloonist, set altitude records in his pressurised gondola and later invented a deep-sea submersible that set depth records.
Piccard said he began thinking about how to make a breakthrough in the field after launching the first non-stop round-the-world balloon ride in 1999. “I should do something to reform transport in modern history,” he said.
The idea of the solar-powered airplane came after a failed attempt to fly an aircraft around the world, in which he ran out of fuel. Piccard decided to create an aircraft that did not need to carry fuel.
The first to respond with help for Solar Impulse was Semper, a Geneva-based private asset management company, followed by others including Altran, Omega, Deutsche Bank and Toyota.
Piccard said he is trying to persuade people to pay more attention to developing alternative energy. “No one could say it is not possible to use [solar energy] in a car or a ship if an airplane can do it,” he said. “It is because the technology required for using it in an aircraft is higher.”
About €40 million of the investment money has been secured from private companies and individual donations at present, mainly from Europe. In a bid to take the message to the other side of the world, Piccard has visited the mainland three times over the past year.
“We are hopeful that more mainland companies will support us,” he said. “For example, we’re hoping Suntech [a mainland solar energy company] will provide us with the solar cells,” Piccard said. There has been no sponsorship from the mainland so far.
Still, he is confident that the remaining funds can be raised easily.
“This is because I raised the first €15 million with a PowerPoint presentation only, long before the prototype of the plane came to exist.”
One of the few remaining problems to be addressed in the prototype before the round-the-world trip takes place is how to upgrade the cockpit with a business-class seat from an economy seat at present.
Three pilots, each flying alone, will complete the five legs of the trip in a total of 20 days. Each will spend at least four days in the cockpit. The seat designer must mitigate the pain and fatigue on the pilots by making the seat as comfortable as possible, given the extreme physical and psychological demands on the pilots during the trip.
Unlike racers, who can boost their endurance with energy drinks, Piccard said these would be forbidden in his round-the-world flight. “Since we have to stay in the cockpit for four to five days in a row, we would like to keep our mind calm,” said Piccard, who has a background in hypnosis. Meditation and hypnosis are techniques Piccard and his fellow pilots will apply during the trip.
Still, it will be difficult to stay awake for four to five days. To deal with that, a vibrating jacket was designed for the pilots that will wake them if their position changes to an odd angle.
Flying the solar-powered plane in the dark is another challenge. In the round-the-world trip, the plane should be capable of flying in the absence of light for 14 hours, Piccard said.
That means the 12,000 solar cells attached to the wings and the fuselage of the plane should be able to store energy for at least 14 hours.
The wingspan of the HB-SIA is as wide as an Airbus 340; however, its weight is just about that of a car – 1,600 kilograms. The plane is designed to fly up to a maximum altitude of 8,500 kilometres, with an average speed of 70 km per hour, on the power equivalent of that needed to light up all the bulbs on a large Christmas tree.
The 20-day expedition in 2012 is scheduled to begin between May and July as it is the period when the earth enjoys the longest period of sunlight. Three pilots, including Piccard, Markus Scherdel, the test pilot and Andre Borschberg, the co-founder of Solar Impulse, will take turns on the trip.
Divided into five legs, HB-SIA will start in Europe and stop over in the United Arab Emirates, the mainland, Hawaii and the United States before completing the loop.
One of the key technologies in the project is the carbon fibre needed for the fuselage. Over the past five years, the Solar Impulse technology team has cut the weight of the material in half.
Piccard does not rule out the possibility of applying solar power in commercial aviation, such as building a hybrid aircraft that can fly on solar power when it has reached a certain altitude. “It is foolish to say that we have the technology at present,” said Piccard. “But it is equally foolish to say it won’t happen in the future.”
Source: SCMP
After 6 years, Solar Impulse prototype passes first test with global flight planned for 2012.