1. Skip to content
  2. Skip to main menu
  3. Skip to more DW sites

Solar flight

September 9, 2010

Two months after the 'Solar Impulse' flew around the clock using nothing but the energy from the sun as fuel, the minds behind the aircraft say they are gearing up to reach new heights.

https://p.dw.com/p/P7mH
The 'Solar Impulse' in the sky
High in the sky: the 'Solar Impulse' does what it does bestImage: AP

When the solar-powered plane takes to the skies again sometime later this month, it won't be testing the endurance of its batteries, but rather will be making sure that its ground crew is ready to make flights of this kind a success.

Andre Borschberg, both the pilot of the 'Solar Impulse' and one of its leaders, announced this week that the plane would be entering its next testing phase sometime in September.

The plan is to make three short-distance hops over Swiss territory - from Payerne to Geneva, Geneva to Zurich, Zurich to Payerne - to see how well the aircraft can be integrated into the flow of everyday business at an international airport.

Bertrand Picard and Andre Borschberg in the hanger, the tail of the plane in the background
Bertrand Picard and Andre Borschberg in the hangerImage: picture alliance / abaca

Borshberg added that the upcoming jaunts are crictical if they are ever to take the plane beyond Swiss borders and land at major foreign airports.

"Our airplane is quite special, it flies slowly, it is very light and is sensitive to turbulence," he said. "We have to know what logistics need to be put in place and to see what kind of collaboration we need to develop with big airports because."

A training exercise

Given the plane's relatively slow cruising speeds - 50 kilometers per hour (or about 31 mph) as compared to the standard 250 kilometers per hour (or 155 mph) for larger aircraft - the ground crew has time to drive from Payerne to Geneva and arrive before it lands. It might sound like a strange exercise on paper, but Borschberg insists that it is all part of getting everyone acquainted with the solar-generated newcomer.

"We have to train the team," Borschberg said, "and see what kind of difficulties we have with traffic arriving and departing."

And that cuts both ways. It is not only the pilot and the ground crew dedicated to the 'Solar Impuse' that have to get used to operating in a very busy environment, but the other aircraft that have to become accustomed to its presence. The fact that the plane, which has solar panels attached to the 63 meter span of its wings, it is so easily thrown off by turbulence means the time between it landing and taking has to be adapted accordingly.

The plane in the hanger
The plane on the groundImage: picture alliance / abaca

"It is quite difficult for people in the control towers, because they are not used to it," Borschberg said. "It is an experiment to get their feedback, to see how it works so that when we fly to another international airport next year, we can propose a way to operate that has been tested and in which we have experience."

Commercial potential?

As yet there is no solid information about exactly where the non-domestic flights might take the 'Solar Impulse.' But wherever it goes, there is a good chance it will attract a lot of attention.

The idea of a plane which can fly without spluttering more emissions into the already choking skies, is a welcome thought, both environmentally and economically.

"Ten years ago fuel was 10 percent of airlines cost and now it is nearly 30 percent," Geoff van Klaveren, aviation expert with the Deutsche Bank told Deutsche Welle. "Any kind of alternative fuel is a thing we have to research."

The plane in the sky
The sky is the limit. Or is it?Image: Solar Impulse

Yet anyone hoping to see this state-of-the-art clean technology ground the world's current airline fleet is in for a long-haul wait.

Commercialization, the 'Solar Impulse' pilot insists, is still a very small dot on the horizon.

In reference to the decades it took between the Wright brothers' first aircraft success and the first commercial transatlantic flight, he stressed that it is a slow process.

"I think we will have to wait a while before we can do the same with passengers, but we have to start somewhere," Borschberg said.

Making history, changing lives

And that it has. In July, 'Solar Impulse' became the first aircraft in history to stay in the air for 26 consecutive hours without any fuel.

The plane took off in the early hours of the morning and spent 14 hours in the air during sunlight hours, enough time for its batteries to charge for the night-time portion of the experiment.

The plane against the silhouette of the moon
Solar-powered night flightImage: picture alliance / dpa

Speaking shortly after the landing, Swiss adventurer and brainchild of the project Bertrand Piccard told reporters that the round-the-clock flight had taken them closer to "the myth of perpetual flight."

But that is not the only goal they have in mind. Both Piccard and Borschberg believe that to make the world aware of how much can be achieved with just four six kilowatt electric motors, is to open eyes to the possibilities on the ground.

"At this stage the purpose of the project is not so much to develop a commercial application but to show what we can do today with this technology," Borschberg added.

He said that as much as anything it is about making people see how with the right technology they can use less energy yet still maintain the same quality of life.

Author: Tamsin Walker
Editor: Cyrus Farivar