New Solar Plane Plans Non-Stop Flight Around The World (bloomberg.com) 35
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.
World record for staying awake? (Score:2, Interesting)
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.
Re: (Score:2)
Really, why is there a pilot? Think of all that wasted energy spent for life support? And who wants to be stuck up there for five days?
Re: (Score:2)
And who wants to be stuck up there for five days?
Burt Rutan and Jeana Yeager, for two. https://airandspace.si.edu/col... [si.edu]
Re: (Score:2)
Re: (Score:2)
The article doesn't say it, but I imagine the pilot will sleep at night, since the plane will glide down during that time anyway. All it would really need is some kind of alarm that's sensitive to time, light, and altitude.
Capacitors! (Score:2)
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.
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:3)
As a spec-built glider, it would be interesting to see if they considered incorporating supercaps into the structure, for example, as the center layer of any honeycomb material. You have to carry the weight anyway; replacing or augmenting something which doesn't provide power seems like a win.
Re: (Score:3)
There are two things that could be important. One is power density and the other is energy density. You could express these in a per-volume measure, but in this case per-weight is important.
Similarly, in this case, it is the ENERGY density that matters.
For perspective, Tesla optimizes their batteries for energy density. But still they get an impressive power-density. IT seems they hit the power-limit when you do a ludicrous mode 0-60MPH. So the 0-60 time improves when you go from 85kWh to 100kWh: not only
Re: Capacitors! (Score:2)
Thanks for the research and calculations.
My impression was that capacitors were not efficient and your calculations indicate that.
I guess they are using them because they have a capacitor factory.
This article confirms your calculations and has a nice chart.
http://berc.berkeley.edu/stora... [berkeley.edu]
Shouldn't that be (Score:3)
"Our flight should prove that it's possible to make long-distance flights using solar energy if you only ever need to fly east"?
Re:Shouldn't that be (Score:5, Interesting)
"Our flight should prove that it's possible to make long-distance flights using solar energy if you only ever need to fly east"?
One proposed use of solar planes is as communications relays, to replace satellites. They would circle the earth continuously, one trailing the previous by about 200 km. They could fly either direction, but flying east wins in both sunlight and prevailing winds (at least in mid latitudes).
Using solar drones instead of satellites for communication is cheaper not just in launch cost, but in the cost of the electronics. Satellite electronics need to be rad-hard, but also need to be super redundant because otherwise a single bad chip can cost $100M. But with a solar drone, if there is a failure in the relay electronics, you just land it and swap out the board.
Re: (Score:2)
Not to mention the round trip times are a lot better... Satellite's latency makes it a non-starter for any kind of interactive traffic.
Re: (Score:2)
Re: (Score:2)
Not if you have a ~800 km altitude constellation.
Round trip latency to a satellite 800km away: 5ms
Round trip latency to a solar drone 100km away: 0.7ms
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
The other advantages of drones over satellites are that you can use a lower power transmitter on the ground device, saving battery power, and you ca use frequencies that don't reach orbit.
Re: (Score:1)
Russia :( (Score:1)
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.
Why not use airships? (Score:5, Interesting)
Re: (Score:3)
why planes? Wouldn't it be better to have some sort of a blimp with thin film solar cells on its upper surface?
At high altitude an airship will be exposed to a lot of radiation which will quickly degrade all plastics. In an airship this will quickly lead to a hull integrity failure and require replacing the entire hull because it's under high levels of stress 100% of the time. In an airplane, even if the plastic parts have reduced integrity, it will still function even if parts of the wing begin to fleck off.
Re: (Score:3)
There are probably real show stoppers with weather, buoyancy etc but you managed to squarely hit something fairly irrelevant as if deliberately testing for ignorance.
Quick calculations... (Score:2)
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 ove
Re: (Score:3)
From memory, The FES electric self launch system fitted to the new Alisport Silent, and LAK Mini self launching 13.5m sailplanes have 4kw/hr capacity from 2 x 15Kg LIPO packs, 22kw motor, controller and charger 20kg for an allup weight of 52kg.
This gives very good self launch, and about 45 min range at over 60kt, depending on conditions and pilot skills.
Cruise uses 4kw continous.
It might be possible to use mountain wave lift to cover significant distances too, particularly useful at night, supplementing th