News Solar Impulse 2 attempts to cross the Pacific

[Spacethingy]

...at 25 knots. Hope they packed something good to read...

Live speed and control surface data from the huge solar-powered craft:
http://www.solarimpulse.com/sitv

SI2 with Bertrand Piccard in the cockpit.

 

[Urwumpe]

5440 ft? Didn't they plan to fly much higher?

 

[MattBaker]

I think the idea is to slowly drop down over the course of the night to save energy and it's a few hours to sunrise where it is now.

 

[Artlav]

AFAIK it climbs up to 30kft or so during the day, then glides down to 5k for half a night and runs on batteries for the other half.

 

[Urwumpe]

Yeah, I thought they are descending during the night in some kind of augmented glide, but it seems like they are flying at about 2000 meters during the night, maybe because the propellers are more effective at lower altitudes.

 

[MaverickSawyer]

Well, that's second sunrise. Keep going, guys! you can do this!

 

[Urwumpe]

Looks like there is some missing telemetry on their homepage.

---------- Post added at 10:46 PM ---------- Previous post was at 10:34 PM ----------

Fixed again, batteries are supported by solar panels, looks like the first night is now officially over. Flying westward now to capture more sunlight.

 

[boogabooga]

Looks like an interesting publicity stunt for climate change awareness, as if the message were not already being blasted already- not that I disagree.

But, the advantage of modern aircraft is speed. If society were to decide that it were acceptable to go back to taking days/weeks for a trip that currently takes an airliner less than a day for the sake of "green-ness", then it would be safer and just as efficient to use a solar-powered blimp...or go back to sailing ships.

 

[Spacethingy]

Sudden teleportation to Japan scientifically linked to happiness:

On a serious note, interesting to see that the batteries go down to a minimum of about 35% charged overnight (judging by the past 2 nights). That's pretty safe...

 

[boogabooga]

And mission is on hold due to weather.

Good luck crossing the Pacific for 6 days and having clear weather all the way.

A lighter than air craft could at least stay above the weather.

 

[Andy44]

I am impressed the thing can collect enough sunlight to charge batteries while climbing to 30k at the same time. I have a dinky solar-powered cell-phone charger, and I have to leave it on the dashboard of my truck for like 3 straight days to recharge it in the summertime.

Looks like an interesting publicity stunt for climate change awareness, as if the message were not already being blasted already- not that I disagree.

But, the advantage of modern aircraft is speed. If society were to decide that it were acceptable to go back to taking days/weeks for a trip that currently takes an airliner less than a day for the sake of "green-ness", then it would be safer and just as efficient to use a solar-powered blimp...or go back to sailing ships.

Yes, a sailing ship would make much more sense and would be much safer, especially with modern radios and backup engines.

But I throw in a vote for dirigibles. Yes, they have their issues when it comes to weather, but come on, tell me a city skyline filled with 1930s-style airships wouldn't be awesome!

 

[jedidia]

Yes, a sailing ship would make much more sense and would be much safer, especially with modern radios and backup engines.

Sailing has one huge disadvantage that discounts it as a means of mass transport nowadays: It's not reliably schedulable.

 

[Evil_Onyx]

Sailing has one huge disadvantage that discounts it as a means of mass transport nowadays: It's not reliably schedulable.

It can be scheduled its just that you have to account for the weather. An Atlantic (Europe to North America or the other way) crossing on a performance yacht takes as little as 6 days([ame="http://en.wikipedia.org/wiki/Banque_Populaire_V"]Banque Populaire V[/ame] holds the record at 3d 15h 25min 48s West to East).

If Sufficient R&D was put in to developing a passenger service, 7-10 day crossings could become reliable.
But the money is not there because its cheaper and quicker to fly in a oil driven aircraft, the same fundamental problem airships and solar aircraft have at present. In the future as oil prices rise, Sail and Solar power craft will get more popular.

 

[Urwumpe]

My two cents there:

Yes, its a publicity stunt. But a pretty good one to showcase what is possible with photovoltaics if you want to. Its sure in no way what the future of air travel will be like. But who knows what kind of job photovoltaics could play in air travel - if light enough, you could produce additional power for the already very electric airliners, which could save a few tons of jet fuel.

Maybe the developments in electric cars will result in viable electric airliners one day. The problem of replacing gasoline with electricity is actually something interesting for airliners, since jet engines have way less efficiency than car engines, so an all electric plane could really become simpler than an all electric car.

And no, speed does not really matter that much for air travel. If you would make it cheap enough, people would also fly from Europe to the USA in 16 hours. Think of a ground effect vehicle there - such a vehicle could get from Europe to the USA in about 24 hours (at 400 km/h), but would require much less fuel per passenger (or passenger comfort)

 

[jedidia]

If Sufficient R&D was put in to developing a passenger service, 7-10 day crossings could become reliable.

Large high-performance sails... a Windjammer mk2, if you will... Hell, it would be an exciting prospect alright! :lol:

 

[boogabooga]

Actually, modern sailing cargo ships are being seriously considered.

http://science.time.com/2013/08/07/video-set-sail-for-greener-maritime-cargo-shipping/

 

[Urwumpe]

And at least are in a prototype state:

 

[Thunder Chicken]

Actually, modern sailing cargo ships are being seriously considered.

http://science.time.com/2013/08/07/video-set-sail-for-greener-maritime-cargo-shipping/

Yep, very seriously. Fuel is one of the bigger (and more variable) expenses, and shipping companies are doing everything they can to knock down that expense:

http://www.skysails.info/

Even before this, shipping companies were going to really big, really slow cargo ships. Fuel consumption rate goes with the cube of velocity (e.g. half the velocity, 1/8th the fuel consumption rate), so the push is to make ginormous ships going really, really slow vs. a fast stream of smaller ships for the same cargo volume rate.

The Panama Canal is being widened in order to accomodate larger ships for this reason. The cargo companies wanted to go wider but the canal lock dimensions were the "bottleneck", quite literally.

 

[boogabooga]

Also, no one said the sails had to be cloth, or even...sails:
http://www.cnn.com/2015/01/16/tech/vindskip-wind-powered-container-ship/

 

[boogabooga]

After a month layover in Japan, they have taken off again for Hawaii.