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Solar Impulse, Continuing World-Spanning Trip, Attempts To Cross The Pacific

Posted by timothy on from the can't-find-your-bags-at-all-sir dept.

The BBC reports that Solar Impulse has resumed its 'round-the-world attempt, having taken off today from Nagoya, Japan for what is intended to be a 120-hour voyage to Hawaii. [If pilot Andre Borschberg] succeeds, it will be the longest-duration solo flight in aviation history, as well as the furthest distance flown by a craft that is powered only by the Sun. The Pacific crossing is the eighth leg of Solar Impulse's journey around the world. But this stage has proven to be the most difficult, and has been hit by weeks of delays." The circumnavigation attempt began earlier this year.

40 comments

  1. It also is the most widely promoted flight... by knwny · · Score: 1

    ...if the newspaper ads in India, when it had a stopover here, are any indication.

  2. a bright future by Gravis+Zero · · Score: 1, Funny

    this is great because it makes it very clear that it's entirely possible to replace our environmentally destructive planes with solar planes. it wont be a simple fix and but it's possible. though naturally it wont happen until it's either mandated by law or becomes more economical.

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    1. Re:a bright future by Dutch+Gun · · Score: 3, Informative

      There's a pretty big difference between a solo flight in an ulta-lightweight solar-powered plane. Note that they've had to wait for months for a clear weather window, and you're claiming that it's now possible to use commercial solar-powered planes? It's sort of like claiming that because we put a man on the moon, we're now ready to build a tourist resort there.

      though naturally it wont happen until it's either mandated by law

      You can't pass a law of physics through legislation. This is cool and all, but don't mistake a this for any sort of substitution for current aviation tech. It's not, and won't be anytime in the near future. We need to focus our efforts on places where it IS feasible to reduce or replace our use of fossil fuels in the relatively near term. Power plants. Cars. Stuff like that. There are many people who are investigating more sustainable aviation fuels, but for the foreseeable future, these are still going to be carbon-based.

      I hate sounding like a naysayer, but you need to be a bit realistic about these sorts of things.

      --
      Irony: Agile development has too much intertia to be abandoned now.
    2. Re:a bright future by BlackPignouf · · Score: 4, Informative

      it makes it very clear that it's entirely possible to replace our environmentally destructive planes with solar planes.

      Once again : Not, it's not possible.
      Here's a comment I posted 5 years ago : http://science.slashdot.org/co...
      The laws of thermodynamics haven't changed much since.

    3. Re:a bright future by Dutch+Gun · · Score: 1

      Oops... first sentence is supposed to end with "and a commercial flight filled with cargo and hundreds of passengers."

      --
      Irony: Agile development has too much intertia to be abandoned now.
    4. Re:a bright future by Gravis+Zero · · Score: 0

      it makes it very clear that it's entirely possible to replace our environmentally destructive planes with solar planes.

      Once again : Not, it's not possible.
      Here's a comment I posted 5 years ago : http://science.slashdot.org/co...

      ...
      Conclusion : The orders of magnitude just don't match, even with 100% efficiency => Commercial flights as we know them & photovoltaics are incompatible.

      by adding "[c]ommercial flights as we know them" you have used the black and white fallacy. solar airplanes could be different in many ways but that doesn't mean they suddenly aren't functional airplanes.

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    5. Re:a bright future by Gravis+Zero · · Score: 0

      There's a pretty big difference between a solo flight in an ulta-lightweight solar-powered plane and a commercial flight filled with cargo and hundreds of passengers. Note that they've had to wait for months for a clear weather window, and you're claiming that it's now possible to use commercial solar-powered planes?

      by changing my claim, you have used the strawman fallacy. i made no claim that this ultra-lightweight solar-powered plane could be used for a commercial flight filled with cargo and hundreds of passengers, only that the underlying technology made it possible.

      --
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    6. Re:a bright future by fuzzyfuzzyfungus · · Score: 3, Interesting

      It's pretty profoundly useless as a replacement for a commercial airliner or cargo plane(basically the wingspan of a 747; but transports a single pilot at a painfully tedious 50-100km/h); but suitably automated versions of the very-long-endurance solar aircraft concept have other uses. Longer life, and greater control, than balloons; but markedly cheaper to launch, and lower ping, than anything in orbit.

      As a manned aircraft it's a pure novelty; but its performance is increasingly close to 'like a small satellite; but closer to the ground and requires only a large strip of pavement for launch and recovery', which could definitely find some takers.

    7. Re:a bright future by tomhath · · Score: 1

      i made no claim that this ultra-lightweight solar-powered plane could be used for a commercial flight filled with cargo and hundreds of passengers,

      You did indeed make that claim:

      it's entirely possible to replace our environmentally destructive planes with solar planes

    8. Re: a bright future by Anonymous Coward · · Score: 0

      Um no, the technology isn't ready yet except is special cases. Off to see wizard straw man err scare crow.

    9. Re:a bright future by Anonymous Coward · · Score: 0

      But you didn't claim they could be "functional airplanes", you claimed they could "replace" the airplanes in use today.

    10. Re:a bright future by BlackPignouf · · Score: 1

      Let's say that a solar plane is white, and a commercial airplane is black.
      I bet that your "functional airplane" is still very much dark gray : you still need a pilot, copilot, food, toilets, a few luggage and minimum space for feet and belly.

    11. Re:a bright future by Gravis+Zero · · Score: 0

      i made no claim that this ultra-lightweight solar-powered plane could be used for a commercial flight filled with cargo and hundreds of passengers,

      You did indeed make that claim:

      it's entirely possible to replace our environmentally destructive planes with solar planes

      you have inappropriately conflated the idea of a solar plane with that particular solar plane's design.

      --
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    12. Re:a bright future by Gravis+Zero · · Score: 1

      Let's say that a solar plane is white, and a commercial airplane is black.
      I bet that your "functional airplane" is still very much dark gray : you still need a pilot, copilot, food, toilets, a few luggage and minimum space for feet and belly.

      perhaps you should watch the video i linked because it doesn't seem you understand what i have written. in any case, a solar plane only needs to be solar powered. there is nothing specifying its shape, size, battery capacity or even propulsion system.

      --
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    13. Re:a bright future by Gravis+Zero · · Score: 1

      It's pretty profoundly useless as a replacement for a commercial airliner or cargo plane(basically the wingspan of a 747; but transports a single pilot at a painfully tedious 50-100km/h);

      you have inappropriately conflated the idea of a solar plane with that particular solar plane's design.

      --
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    14. Re:a bright future by BlackPignouf · · Score: 1

      there is nothing specifying its shape, size, battery capacity or even propulsion system.

      Except laws of thermodynamics, that is.

    15. Re:a bright future by Gravis+Zero · · Score: 1

      there is nothing specifying its shape, size, battery capacity or even propulsion system.

      Except laws of thermodynamics, that is.

      my point does not conflict with the law of thermodynamics. either cite a conflict or concede.

      --
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    16. Re:a bright future by BlackPignouf · · Score: 1

      The burden of proof is on you.
      I showed that typical airplanes would need 500m2 of pv panels per passenger in order to fly, even with a perfect propulsion system and maximum solar irradiance.
      You need to describe a functional airplane that somehow needs about 10 or 100 times less pv panels to fly.

    17. Re:a bright future by ceoyoyo · · Score: 2

      That particular plane is designed the way it is not because they thought it looked cool, but because the realities of solar power require it. All the methods of harvesting solar power are heavy and bulky per kilowatt compared to something like aviation fuel. That means you need to have a plane that is slow (for energy efficient flight), very large (lots of area for solar panels and big wings for slow flight), and has a small cargo capacity for its size.

      Even with improvements in solar panel design, the amount of sunlight that reaches the plane is limited.

      The best design for a solar plane with the capabilities of current planes might well be a regular solar farm powering a conventional fuel synthesis plant.

    18. Re:a bright future by fuzzyfuzzyfungus · · Score: 2

      The design can be changed; but this design is as it is in large part because of how much surface area it needs to collect enough sunlight to sustain even its distinctly frugal operation.

      Improvements are likely, with better solar panels, better batteries, or both; but you don't beat the fact that optimal insolation is 1366w/m^2; and real world values typically lower, at least on average. A liter of Jet A is 35.3 MJ, so ~9880watt/h. Even at peak insolation, a square meter of solar collection takes a little over 7 hours to amount to as much energy as a liter of jet fuel. Jet engines are, of course, hardly perfectly efficient; but you get some sense of perspective from the fact that a relatively modern design, aimed at fuel efficient operation, like the 787 still has storage for in excess of 100,000 liters of fuel, a big 747-400 more like twice that.

      On the plus side, your sunlight supply doesn't weigh anything, or require any volume(though your batteries do, and barring major improvements their energy density is dreadful compared to hydrocarbons); but even given perfectly efficient solar hardware, there just isn't that much energy to work with, by the standards of hydrocarbon aircraft. Any possible design is going to reflect this through some combination of gigantic wing area per unit capacity and a flight plan that sticks relatively carefully to maximally efficient speeds.

    19. Re:a bright future by wagnerrp · · Score: 2

      The idea of solar powered heavier-than-air flight necessitates this manner of design.

    20. Re:a bright future by wagnerrp · · Score: 1

      Not "commercial flights as we know them", just "commercial flights, period". Commercial aviation only exists because it exists as it does. You mandate solar power, and now you've mandated aircraft that are no faster than wheeled vehicles. Transportation would shift back to those vastly cheaper wheeled vehicles, and commercial aviation would all but go away.

    21. Re:a bright future by tomhath · · Score: 1

      You don't seem to understand what you have written.

      You claimed that this prototype aircraft "makes it very clear that it's entirely possible" to replace fossil fueled aircraft with solar powered aircraft. The only thing that Solar Impulse has made clear is that a solar powered aircraft can be flown; there is nothing to indicate that a solar powered aircraft of any design or any efficiency can possibly replace fossil fueled aircraft as you claimed.

    22. Re:a bright future by Dutch+Gun · · Score: 1

      The best design for a solar plane with the capabilities of current planes might well be a regular solar farm powering a conventional fuel synthesis plant.

      This. As one example, researchers are investigating ways to use sunlight, water, and carbon dioxide in the air itself to synthesize kerosene. If we can manage to do that on an economically viable scale (which would mean building these plants on a massive scale), it would make a serious dent in curbing our fossil fuel appetite.

      You simply can't beat the efficiency of hydrocarbon fuels in terms of released energy for a given weight and volume (as fuzzy gives us some hard numbers below), and that's crucially important for aviation. At the moment, there simply isn't any viable alternative.

      --
      Irony: Agile development has too much intertia to be abandoned now.
    23. Re:a bright future by Huge_UID · · Score: 1

      The laws of thermodynamics haven't changed much since.

      Stupid do nothing congress.

    24. Re:a bright future by thinkwaitfast · · Score: 1

      The burden of proof is on you.

      Don't argue with people who can't do math or know basic science at a secondary level and they eventually go away

    25. Re:a bright future by BlackPignouf · · Score: 1

      I tend to agree. But it took me a long time to realize just how much energy is contained in one litre of oil. Before that, I also thought that everything was possible for transport.

    26. Re:a bright future by fuzzyfuzzyfungus · · Score: 1

      Some of the (often excitingly dreadful) stuff used by the orbital-launch rocketry guys might beat hydrocarbons on pure energy density; but I suspect that civil aviation may not be ready for hydrazine spills on busy runways and range safety officers blowing up the occasional airliner.

      The exciting thing about solar aircraft(aside from it being cool that they are possible) is that, if you can get efficiency high enough, they are basically your only option for long-to-indefinite loiter. In-air refuelling costs a small fortune, so hydrocarbons are mostly out; and nuclear, the only other long-lasting fuel source; has been explored; but you don't name a project after the god of the underworld because it satisfies more conservative risk analysis.

    27. Re:a bright future by ceoyoyo · · Score: 1

      I knew a guy in grad school who was working on synthesizing oil and hydrocarbon fuels by microwaving manure. You didn't want to warm up your lunch in his lab.

  3. Dear Slashdot Management by DeadBeef · · Score: 4, Insightful

    Please return the user interface to how it was. You are just pissing the long term userbase off.

    Pulling out the read more link is like pulling the start button / menu from windows 8. It is a user interface disaster because it's not obvious w\
    here you should click for the comments.

    Slashdot has always been about the comments, if you minimise them by obfuscating the link to them you are left with the news stories from reddit \
    a couple of days late and some obvious paid advertising plants.

    Implementing aspects of the failed beta interface piecemeal with no discussion seems a bit underhanded.

    If you aren't lucky you might succeed at killing slashdot which would be a shame.

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    1. Re:Dear Slashdot Management by Anonymous Coward · · Score: 0

      click on the number in the black talk balloon

      SLASHDOT SAVED AGAIN!!!!1

    2. Re:Dear Slashdot Management by DeadBeef · · Score: 1

      I'm loving the irony of you letting people know where the link is to the comments inside the comments section.

      The AC braintrust has done well.

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    3. Re:Dear Slashdot Management by terriblesharebutton · · Score: 0

      It's been a UI element in that exact place since the site was created (https://web.archive.org/web/19980113191222/http://slashdot.org/) 17 years ago!

      I found it so hard to rewire my muscle memory that I had to install Tampermonkey and write this script to restore it to how it was:
      http://pastebin.com/wZKjNi1S

      I hope they change it back. It doesn't even scan well any more, you have to take your eyes off of the summary text, pan all the way to the right to figure out how much discussion there's been on an article.

    4. Re:Dear Slashdot Management by AmiMoJo · · Score: 1

      It's the lack of communication that really upsets people. At least discuss your plans for the site, and explain your decisions.

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  4. a long time to hold it by Anonymous Coward · · Score: 0, Funny

    120 hours is a long time to hold off going to the toilet. Unless you just go and eject it or something.

    1. Re:a long time to hold it by Anonymous Coward · · Score: 0

      Technically the world is everyone's toilet, as not even the astronaut's waste go anywhere but this planet we live on.

    2. Re:a long time to hold it by fsagx · · Score: 1

      True, except for some of the Apollo guys.

      Moon Toilet

  5. Title Is The Worst Haiku Ever by Anonymous Coward · · Score: 0

    Solar Impulse,
    Continuing World-Spanning Trip
    Attempts To Cross The Pacific

    It's not even the 5-7-5. It's 4-8-8!

  6. Say Hi To Amelia by Anonymous Coward · · Score: 0

    Because the two of you shall surely meet.