Aircraft

Solar Impulse takes off on longest leg of round-the-world flight

Solar Impulse takes off on lon...
Solar Impulse 2 taking off from Nanjing, China towards Hawaii
Solar Impulse 2 taking off from Nanjing, China towards Hawaii
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André Borschberg in front of the media before boarding Solar Impulse 2 to attempt the first oceanic flight of the world journey
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André Borschberg in front of the media before boarding Solar Impulse 2 to attempt the first oceanic flight of the world journey
Solar Impulse 2 taking off from Nanjing, China
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Solar Impulse 2 taking off from Nanjing, China
Solar Impulse 2 taking off from Nanjing, China towards Hawaii
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Solar Impulse 2 taking off from Nanjing, China towards Hawaii
Bertrand Piccard and Prince Albert II of Monaco just before take-off at the Monaco Mission Control Center
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Bertrand Piccard and Prince Albert II of Monaco just before take-off at the Monaco Mission Control Center
Bertrand Piccard and Prince Albert II of Monaco giving the final go to André for take-off at the Monaco Mission Control Center
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Bertrand Piccard and Prince Albert II of Monaco giving the final go to André for take-off at the Monaco Mission Control Center
Bertrand Piccard, Prince Albert II of Monaco, and Mission Director Raymond Clerc just before take-off at the Monaco Mission Control Center
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Bertrand Piccard, Prince Albert II of Monaco, and Mission Director Raymond Clerc just before take-off at the Monaco Mission Control Center

With Swiss pilot André Borschberg at the controls, the solar-powered, single-pilot Solar Impulse 2 airplane took off from Nanjing Lukou Airport in China today bound for Hawaii on the longest leg of its round-the-world flight.

This isn't just a major leg of the Solar Impulse 2 solar-powered circumnavigation, it is also an attempt at the longest duration flight ever by a solo pilot in any type of aircraft. Confined to his cockpit not much larger than a first class airline seat, Borschberg will be in the air for 130 hours, or about five nights, as he flies 8,172 km (5,078 mi) on his way to the Hawaiian Islands. During this time, he will be in constant contact with the Mission Control Center in Monaco, which is monitoring the aircraft and conditions on the route in front of it.

With its 72-m (236-ft) wingspan, the Solar Impulse 2 is wider than a Boeing 747-8I, but weighs only about 2,300 kg (5,070 lb). Part of the reason for this is that it's made out of carbon fiber, employing a light single-ply technology used in competitive yachting which makes it three times lighter than paper. Its four electric motors are powered by 17,248 solar cells 135 microns thick. These are built into the wing and protected by a fluorine copolymer film, which feed banks of high-density lithium polymer batteries weighing 633 kg (1,395 lb).

In flight, the plane is charged by the Sun during the day and powered by batteries at night for "virtually unlimited autonomy" and an average speed of 50 to 100 km/h (31 to 62 mph).

André Borschberg in front of the media before boarding Solar Impulse 2 to attempt the first oceanic flight of the world journey
André Borschberg in front of the media before boarding Solar Impulse 2 to attempt the first oceanic flight of the world journey

Solar Impulse 2 began its flight in March 9 at Abu Dhabi in the UAE. It then flew in hops to Muscat, Oman; Ahmedabad and Varanasi, India; Mandalay, Burma (Myanmar); and Chongqing, China before reaching Nanjing. If the aircraft lands in Hawaii successfully, its next stop is Phoenix, Arizona.

"This is the exploration leg of the flight around the world. It will be an important milestone for aviation with an airplane capable for the first time ever to fly with unlimited endurance. This represents an extraordinary illustration of technological innovation which André initiated and led during the last 12 years," says Bertrand Piccard, Solar Impulse Chairman, initiator and pilot.

The video below shows the takeoff of Solar Impulse 2 from Nanjing.

Source: Solar Impulse

6 comments
Tom Benson
"it is also an attempt at the longest duration flight ever by a solo pilot in any type of aircraft" Not even close: Steve Fossett : the first person to fly solo nonstop around the world in a balloon.
Daishi
So the sun came up and it looks like the plane is charging. I think the battery dipped to a low of about 36% this morning before the sun came up. The lowest altitude was about 5,000 feet. They are going about 28 knots now (~30MPH) for airspeed which is a little lower than the average figure above. Ground speed is higher (~40 MPH). They have a lot of info on their website. Right now the panels are pulling in 26 kW, the plane is using 23 kW to fly and charging the batteries with the remaining 3 kW. From the infographic posted to the website it looks like they are planning for the trip to take 6 days and nights: http://i.imgur.com/TCE3w33.jpg Here is an infographic that gives the technical details of the plane/batteries etc: http://i.imgur.com/w1GGSfQ.jpg I'm not sure what an energy density of 4x260 Wh/kg means exactly. Maybe that means there are 4 batteries all with a 260 Wh/kg density? Seems like a strange way to represent the number but for context a Model S is around 240 Wh/kg I believe and the roadster was about half that. Here is a quote from their website related to their panel efficiency: >More than 17’000 solar cells, collecting up to 340kWh of solar energy per day and representing 269.5 m2! >More precisely 17'248 monocrystalline silicon cells each 135 microns thick mounted on the wings, fuselage and horizontal tailplane, providing the best compromise between lightness, flexibility and efficiency (23%). For context most residential panels are only about 17-18% efficient and they aren't that thin. It should be an interesting project to keep tabs on. Now that they can fly all night on battery they can pretty much stay in the air till the pilot runs out of food and supplies. What a time to be alive :)
Jason Catterall
Will he be able to get any sleep during the 130 hours?
AlB
This will only help the world to Open their eyes of the possibilities of what Solar Power can really accomplish ! Bright future Ahead for sure .
Charles S Roscoe
Still on schedule, I see to catch the Hurricane season over the Atlantic later on.
Magnetron
This is a fascinating feat, however I'm confused about how he has got permission from the regulatory bodies governing the airspace to allow him to do such a long flight without stopping for a break. Maybe he can sleep while the aircraft is on Autopilot? It'd be extremely sad and dangerous if he crashes due to fatigue, which is why pilots have to adhere to very strict rules regarding flying hours. I wish the project luck.