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New Solar Plane Plans Non-Stop Flight Around The World (bloomberg.com)
An anonymous reader quotes Bloomberg:
[A] Russian tycoon and his Renova Group plan a record-breaking effort to send a plane around the world nonstop using only the power of the sun. If all goes well, a single pilot will fly for five days straight at altitudes of up to 10 miles, about a third higher than commercial airliners. The project isn't just a stunt. The glider-style airplane with a 36-meter (120-foot) wingspan will be a test of technologies that are set to be used to build new generations of autonomous craft for the military and business, say aerospace experts. They will fly continuously, have far greater reach and control than satellites and expand broadcast, communication and spying capabilities around the globe... "Our flight should prove that it's possible to make long-distance flights using solar energy," said Mikhail Lifshitz, Renova's director of high-tech asset development and a qualified pilot-instructor. A "flying laboratory" test-plane will be ready by year-end, Lifshitz said in an interview.
The plane will conserve power by slowly gliding down from the high altitudes at night -- without ever touching the ground. In comparison a solar plane (partially funded by Google) already circled the earth last year -- but it took 22 days, and made 17 different stops.
The plane will conserve power by slowly gliding down from the high altitudes at night -- without ever touching the ground. In comparison a solar plane (partially funded by Google) already circled the earth last year -- but it took 22 days, and made 17 different stops.
TFA Says there will only be a single pilot. If the attempt succeeds, this will demonstrate either how someone can (legally?) stay awake for five days AND command an aircraft during that time. There will be some interesting legalities to be defined here, bearing in mind the different national regulations governing drugs, pseudo-autonomous aircraft and combining the two.
Interesting that the plane will use supercapacitors rather than batteries to store energy for use at night. I guess power to weight is favorable.
He divested from oil (smart move) and into tech and has a large supercapacitor factory.
I don't read your sig. Why are you reading mine?
"Our flight should prove that it's possible to make long-distance flights using solar energy if you only ever need to fly east"?
I can assure you, the best way to get rid of dragons is to have one of your own.
Just ground your fleet - non-stop flights galore.
etc.. what a surprise? some still calling this 'weather'? cease fire stand down,, hugs not thugs,, end wmd on credit genocides in our lifetime.. that's the spirit.. thanks again
that would be so homey & frugal at the same time..? sing along.. https://www.youtube.com/watch?v=H-kA3UtBj4M
People might be impressed if it was not Russia. Russia has more land, more mineral resources, more technical acumen and more educated people than pretty much anywhere else on the planet. It's GDP is equivalent to Connecticut. Bad manglement.
I think it's fine to use devices in the atmosphere to relay our communications signals, but why planes? Wouldn't it be better to have some sort of a blimp with thin film solar cells on its upper surface? These could provide energy for maneuvering the various layers of moving air to maintain a reasonably constant position. Alternately, it could just be at the end of a long tether. I think that's a much more elegant way of keeping up altitude overnight.
That green thing (T-62 on the linked page provided) will take more than solar power to fly.
If your plane has a glide ratio of 1:60, and weighs 1600kg then to fly 40000km, you need 40.10^6/60*1600 = 11GJ of energy.
If your plane has 200m^2 of solar panels with 45kW peak output, you have to realize that the sun is shining on the wrong side of your panels (and the earth is likely in the way) half the time. Also even when it's on the right side, it won't be perpendicular. You can't turn your panels to the sun because you're using them as a wing too. So you can only expect a about 25% of peak power over longer periods (more than a day). So, in five days you get 5*24*3600s*11.5kW = 4.9GJ of energy. from the solar panels...
There is a factor of two of discrepancy between the back-of-the-envelope and what they say they will achieve. Twice as efficient solar panels? I don't think so. This 45kW/200m^2 is already state-of-the-art. Getting two times more wing surface means you won't be able to fly as fast, and it's going to be a challenge to keep the weight at 1600kg.
Talking about speed, 40000 km in 5 days means 333 km/h. or 92m/s. Gliding at 1:60 means you need to make up for 1.5m per second, or 1600*9.8*1.5 = 24kW. About twice what you can expect from your solar panels.
But if we take 200m^2 of wing area, and 8kg/m^2 of wingloading, you'll fly at 10m/s at sea level. Fly at 25% atmospheric pressure 13km? you'll go twice as fast. They want to go 92m/s or 4.6 times faster. You need about 21 times less wing-area to fly 92m/s at 13km height. That's not going to happen.
The numbers for weight, wing surface and flying speed at sealevel were taken from "solar impulse". The 1:60 glide ratio is a "good sailplane". Note that such a sailplane won't have props sticking out, or pods to house motors.
It could be that they manage to improve their average speed enormously by using the jetstream. Not sure if it will make up for the big difference in energy requirements....