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Solar-Powered Plane Makes First Successful Flight
lilbridge writes "The Solar Impulse, a solar-powered plane covered in 12,000 solar cells, took its maiden flight today in Switzerland. The plane stayed aloft for 87 minutes, performing test maneuvers as well as completing a successful takeoff and landing. With the first test flight behind them, the developers can focus on gearing up for their around-the-world solar powered flight set for 2012."
That's pretty bold of them, attempting a round the world solar powered flight test during the Apocalypse. God speed.
Authority questions you. Return the favor.
They won't come close to matching Earth's rotation, so I don't see a point to dragging out the length of night and thus requiring larger batteries.
"Now we're getting to Science -- I love this!" -- Dr. Steven Chu, Energy Secretary confirmation hearings.
I get the same giddy enthusiasm that I got back in the '80's with the Voyager.
But that is a very interesting question about which direction they would fly.
I would venture they might take tradewinds/jet stream into account, perhaps some thermal updrafts too, over merely following the sun.
--alop
Does it store enough energy so it can fly late evening or during rain?
Well, it doesn't have much to do with "Your Rights Online" ;)
--alop
Well it certainly isn't SOFTware.
Partly cloudy with a 100% chance of crash.
So, when you jump in the air the Earth rotates under you? Yeah, I didn't think so.
What we need is a solar-powered plane capable of safely carrying a couple dozen people 500 miles.
This represents the first solar-powered flights ever. Not the plane in this article.
I guess we've forgotten:
From the article:
Really? And this is impressive how? Seven years to reinvent existing technology? Puh-lease.
"There is a way that seems right to a man, but its end is the way of death." Proverbs 16:25 (NKJV)
"an average speed of 70 kph" - "won't come close" is an understatement.
I would think you'd aim to build something that can act as a glider (and the long narrow wings in the picture look like they are) at night. With batteries giving engines when you need them, but not requiring batteries big (and heavy) enough to last the 18 hours or so when the sun is either not visible too low for the solar panels to generate much power.
Either way, you are going to east with the jet streams - that's going to have far more impact than day length variance.
That's the point I think. If it could keep up with Earth's rotation it could be kept under constant sunlight (or, at least, under an extended period of sunlight) roughly like a sun-synchronous orbit.
English is not my first language. Corrections and suggestions are welcome.
Earth's circumference = 24,900 miles.
They have to keep pace with the sun, to have the sun directly overhead to get maximum panel output, which means covering 24,900 miles in 24 hours, or 1,037 mph. In other words, they need to be mucho supersonic - good luck with those propellers.
Even at half that, they end up in the dark and out of power - and there's no way that they can get to 500 mph with that design (and we're ignoring that the sun would be at a lousy angle for much of the flight).
At 44 mph, it's going to take them 3-1/2 WEEKS to make the trip. Better stock up on food, water, and lots of Depends (because sh*t happens).
In other words, unless they have some big-ass batteries, or they get the pilot to pedal a lot, or they glide all night (not very practical and will stretch out the flight to a week or more), they really need to upgrade their math skills.
The article says the plane averages 44mph (70kph). At that rate it will take about 24 days to circle the earth if they tried it in a single flight. Hopefully they will be able to get a little more speed before they try that.
Ninjas don't carry tic tacs
but how much did it cost?
it didnt say that in TFA
equatorial circumference. Move very near to the pole and you can manage to stay in sunlight (unfortunately oblique, so you might not get enough energy) permanently.
Sorry, but you've not thought through your objection. The plane isn't jumping straight up, for one thing, and for another, the winds generally blow in a given direction at a given latitude.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Secret labs are working on a stealth version that flies exclusively at night ... wait there's a flaw in there somewhere ... DOH!
You should probably email them so they don't miss any of your brilliant tips, since they probably haven't considered any of those points in their design and analysis.
Well, if you move TO the pole, you can send a paper airplane "around the world" ... cover every single longitude ... with one throw.
So go to the north or south pole - you can throw a paper airplane so it passes through every line of longitude.
But nobody would count that as going "around the world."
I'm not assuming, I'm trusting what the builders/designers state:
http://www.solarimpulse.com/en/documents/challenge_gamble.php?lang=en&group=challenge
though I should state that I did make a typo, read 16 where I wrote 18.
And for a round the world flight, I'll definitely need one of those in-seat video whats its and some stiff drinks. I'll bet the emergency videos are really tedious. *sniff*
As one of the designers of the system, I have just this to say... gosh, we never thought of that. Looking at the designs again in light of your insightful, informed comments it's clear that we're all insane and or incompetent for designing this thing. We should have realized sooner, but I guess we were all to drunk/high to notice.
END SARCASM
This was designed by engineers with experience in the field. They know all about power to weight ratios, wingspans, and surface areas. The fact that you were able to come up with your objections with about 30 seconds of thought should make you realize that the engineers involved probably came up with the same concerns somewhere along the 7 year development cycle. As for it being miserable to fly... of course it is, this isn't a sport plane or even a transport plane, it's a proof of concept at best (and I don't really see how the concept could ever really be made into anything other than a gee whiz toy).
> A 15 horsepower plane is a really, really unsafe and miserable vehicle. It's
> just an underpowered and fragile disaster waiting to happen.
15hp continuous is not 15hp peak. It has batteries.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
The first solar powered aircraft took wing in the 1600's. As told in The Mysterious Cities of Gold!
I fail to see what this has to do with iPad but now that YOU brought it up... Can I charge my iPad while flying in this thing?????
No. It's "Your Wrights Online"
Intron: the portion of DNA which expresses nothing useful.
Having the plane computer-controlled would require more solar energy.
English is not this
So, when you jump in the air the Earth rotates under you? Yeah, I didn't think so
What an extremely funny comment - obviously you've never taken a long flight. Take off from San Francisco in the morning and go to somewhere in SE Asia on a commercial airliner and the sun will be up the whole way thanks to the plane's speed. BA a few times had "new year's eve around the world" flights because the Concorde was faster than the Earth's rotation with time to spare for refueling.
That's what the GP was wondering about, not you hopping in place, silly. Still, at 70mph, this solar plane doesn't have a chance.
The plane stayed aloft for 87 minutes, performing test maneuvers as well as completing a successful takeoff and landing.
Gosh, that is novel. So first it flies for 87 minutes, does several maneuvers and THEN even manages a successful takeoff. Didn't see that one coming. I thought it had crashed on takeoff, but no.
Pedantic? You bet.
It as bad as, "he died from his injuries which are believed to have been lethal". No kidding.
Less is more editors. Some of us can read between the lines, especially when they are written in editor crayon. What next, "the red firetruck was red"?
You must be a lot of fun at parties.
Did it not cross your mind that there was the possibility that such a plane was dropped from a carrier aircraft, and hence it was necessary to specify in the article that this thing took off under its own steam?
Drill baby drill - on Mars
I don't see any reason for the vituperation. I did not attack the designers, I just mentioned some obvious facts to compensate for people's superficial understanding of flying objects. Slashdot tends to be a bit too gee-whizzy in its enthusiasms. I think there's room and need for a little factual balance.
"At the equator only... If you fly "around the world" at a higher latitude (longitude?), the diameter is much smaller and the required speed to stay in the sunlight is much lower."
Everyone assumes to fly around the World means flying at a constant longitude. At any latitude you can fly "around the world" equal in distance to the circumference of the Earth (assuming the earth is a sphere) at the equator by flying the arc of a great circle (remember your spherical trigonometry?).
It's just an underpowered and fragile disaster waiting to happen.
Saying this about a project an engineer has devoted 7 years of their life to is an attack on that engineer. It implies that they don't know what they're doing, that they're uninformed, that they're idiots. Thinking that you can outsmart someone who is demonstrably more knowledgeable and experienced about the subject (unless of course you happen to have a solar powered plane in your garage) insults that person.
I think there's room and need for a little factual balance.
And you did a fantastic job of failing to provide any.
Saying the plane is a "disaster waiting to happen" is wrong, stupid, and yes, an insult to the designers for implying they'd make something that some random /.er can see in two seconds is going to be brought out of the air by rain.
Oh lol right, you're Ancient Hacker, the guy who trolls by claiming to be a 'hacker' who is nearly universally wrong on every technical subject.
The enemies of Democracy are
>15hp continuous is not 15hp peak. It has batteries.
Yep, and it's going to need them for situations like takeoff, climb, rain, downdrafts, clouds, night, or icing.
But that means the rest of the time it has *less* than 15hp to work with if it's going to use some of its sun power to recharge the batteries. No free lunch.
The plane stayed aloft for 87 minutes, performing test maneuvers as well as completing a successful takeoff and landing.
Gosh, that is novel. So first it flies for 87 minutes, does several maneuvers and THEN even manages a successful takeoff. Didn't see that one coming. I thought it had crashed on takeoff, but no.
The expression "as well as" does not imply when this successful take off occurred within those 87 minutes. Reading between the lines as you stated and applying a touch of logic would imply that the take off was the first thing to happen within the time mentioned. Also, just because an airplane is capable of powered flight, does not necessarily make it capable of an unassisted take off. If only 87 minutes of powered flight was mentioned, the plane could have been dropped from a balloon and crashed into a barn at the end of its flight. If you are going to be pedantic, at least be thorough.
Correction, constant latitude.
The plane stayed aloft for 87 minutes, performing test maneuvers as well as completing a successful takeoff and landing.
I assumed the editor knows nothing about what the journalist is writing about. Usually, this is a correct assumption. In fact usually journalists know nothing about what they are writing about. He probably "corrected" it from "successful landing and takeoff" to make it sound better. What they were dancing around was:
http://en.wikipedia.org/wiki/Touch-and-go_landing
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
If you're near one of the polar regions then the axial inclination means that either night or day will be much shorter (depending on the time of year). If you time it right, you can go around with only an hour or so of night. Of course, then you're not flying a great circle, so it's cheating. You can probably pick a great circle that gets more sunlight than an equatorial flight though, with some careful timing.
I am TheRaven on Soylent News
Pedantic? You bet.
No, not really.
What passes for pedantry on /. has really gone down hill over the years in my crotchety old opinion. It's gone from nitpicking the usage of words that actually have highly specific technical definitions that it actually makes sense to be pedantic about, to trying to find the stupidest way to fail to understand everyday English sentences.
The enemies of Democracy are
Or study some weather. It is called the Coriolis effect (if I'm spelling that correctly).
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
Not saying there is a free lunch, but with the light weight and wingspan it has, it has a 40:1 Glide Ratio so if I power up my engines to climb really high. This extra altitude becomes potential energy that I can play out at a 40 to 1 ratio, 40 miles travelled forward for every mile I drop in altitude. Since its travelling ~44 mph, that's about an hours worth of travel just on gliding, can an hour's worth of charge make up for the energy spent gradually climbing 1 mile in altitude?
Do you climb during the brightest overhead sunlight?
I can't find the place where you calculated the available sunlight, but did you include the fact days are appreciably longer with stronger sunlight above 35,000 ft?
um.....did you think that out or is this a *whoosh* moment? If you are flying west and then east then your not really going to get very far, or if the flight times are different it's going to take you a hell of a long time, especially at 70kph.
letting an idiot know they are an idiot is not a game... it's a responsibility. - by Kristopeit, M. D. (1892582)
This thing is nearly as big as a bomber. Seems to me the square-cube law (with power going with square and weight to be flown going with cube) would favor smaller machines - unless the density of the solar cells combined with a fixed thickness, and/or the weight of the control computer and hardware, imposed a limit.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Riiiight. And then you'd be complaining about the redundancy of saying that it wasn't dropped from a carrier plane, it would have been easier to just say that the plane took off itself (which is what TFA actually says).
Drill baby drill - on Mars
So they don't really fly at night.
They often don't fly at night, but since a record was set in 1952 for a 56h 15m flight, I don't quite think you can say they can't stay aloft after dark (although I suspect Messr. Atger was probably using ridge lift rather than convection to keep airborne during the night).
MCSE? No, sir...I don't do Windows. Yes, I am an idealist. What's your point?
It's not good until it can also be driven on the roads. I WANT MY FLYING CAR.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
That's soaring not gliding...
You want a large glide ratio so you can lose as little altitude as possible (for distance traveled) at night (or alternatively use the engines as little as possible to maintain altitude).
Get as much altitude as you can during the day when power is plentiful, lose as little as possible at night.
No, it doesn't really do that. His comment may have been blunt, rude even, but there's no evidence that he was attacking the engineers personally, only the project's effectiveness in developing a practical application.
Don't get me wrong. I agree with you. His comment was in poor taste. But strictly speaking, nothing he said is an affront to you or your considerable achievement. You're reading too much into it. Maybe he really did mean it the way you interpreted it, but you should try to avoid getting this offended until you know for sure that personal attack was intended.
That said, congratulations on your work. I look forward to the day that this technology matures into practical applications. :)
You're right, I wouldn't steal a car. But if it were possible, I sure as hell would download one!
They will fly it above the polar circle latitude...problem solved!
Actually, for flights which would take a little longer than 12 hours, it might be possible to take off on the morning and land on the evening several time zones westward, thus gaining a few hours of sunlight. while it would not match the rotational speed of the Earth, except near poles, it could still be effective.
There is also the fact that taking a plane to go a short way eastward, it would make no sense to go westward and fly around the Earth, so this applies only to long flights.
I'm way more concerned about how it performs if the weather is cloudy, though that might not be a problem once it reaches upper atmosphere above the clouds, it could be a problem for take-off.
If I'm wrong, please correct me ; learning is better than being right.
>Saying the plane is a "disaster waiting to happen" is wrong, stupid, and yes, an insult to the designers for implying they'd make something that some random /.er can see in two seconds is going to be brought out of the air by rain.
I'm sure the designers did not intentionally make something so un-airworthy-- they're just constrained by the very low power available. You can't change the basic amount of power available, so you have to compromise on everything else. The wing is going to have to be long and huge, both for solar collection area and to get a low wing-loading, good glide ratio and low stall speed. It's going to have to be built as lightly as possible, which means it can't stand much stress. Planes that are certified have to be capable of +3 and -1G stress, but one suspects this plane has much narrower margins. That makes the plane much more susceptible to damage from turbulence and limits its maneuverability.
With a low landing speed and long wings, it's going to be in deep doo-doo when landing in a cross-wind. Your really maneuverable planes are limited to crosswinds on the order of 25% of landing speed. This plane is NOT very maneuverable, and cannot be banked very much on approach due to its long wings. That probably limits it to a cross-wind component of maybe 10%. With its low landing speed, that means anything over 4MPH is going to be a HUGE problem.
I'm sure the designers did the best they could within the power and weight limits. But still the best you're gonna get is not going to ever be certifiable as an airplane.
You are presuming that the goal is to travel in a specific direction. I think the goal of the GP was to maintain flight as long as possible by spending as much time as possible in daylight, and as little time as possible in the dark.
They won't come close to matching Earth's rotation, so I don't see a point to dragging out the length of night and thus requiring larger batteries.
Was't sure about that, so I crunched the numbers:
s = Circumference of the earth = 40 041.47 kilometers
t = Period of orbit = 1 day
v = s/t = 463 m/s = 1 667 km/hr
Actual speed achieved in article: 70 km/hr
If they can increase the power by a factor of 24, they could do it. Given that this is a proof of concept, it'll probably be feasible in a few decades.
Most human behaviour can be explained in terms of identity.
I could understand that but the stated goal of the people doing this was to travel around the world.
letting an idiot know they are an idiot is not a game... it's a responsibility. - by Kristopeit, M. D. (1892582)