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Solar Powered Plane Completes Cross-Country Flight
An anonymous reader writes "The Solar Impulse, a solar powered aircraft, landed at New York's John F. Kennedy International Airport completing its historic cross-country flight. From the article: 'The flight plan for the revolutionary plane, powered by some 11,000 solar cells on its oversized wings, had called for it to pass the Statue of Liberty before landing early Sunday at New York. But an unexpected tear discovered on the left wing of the aircraft Saturday afternoon forced officials to scuttle the fly-by and proceed directly to JFK for a landing three hours earlier than scheduled. Pilot Andre Borschberg trumpeted the milestone of a plane capable of flying during the day and night, powered by solar energy, crossing the U.S. without the use of fuel.'"
Although I realize this is probably a big achievement, I was a little disappointed to find out that this wasn't done in a single flight, but rather many smaller trips with stops in between. I can't believe this wasn't mentioned in the summary, Makes the news sound much more spectacular than it actually was. I really don't think you can count this as a cross-country flight when it had to make multiple stops along the way. Really, it's just a series of short flights in the same direction. It's not like when somebody runs across the country, and we just all assume it wasn't non-stop, with a plane we kind of assume that there wasn't any stops.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
I doubt it'll be useful soon but down the road who knows. It was a few decades between the wright brothers and the age of the Airliner. Time and technology march on.
Drones. A weapon armed with a couple of Hellfire missiles that can stay in the air 24/7, ready to blow up a wedding party at a moment's notice. Could also be useful for spying - cloud cover can scupper satellites.
const int one = 65536; (Silvermoon, Texture.cs)
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I don't mean to be a whiny spoilsport, but with all the congestion in the airspace around NYC, why did they pick JFK to land a slow-moving and delicate aircraft?
There are numerous airports at the periphery that are significantly less busy, like Stewart International or Islip/McArthur that could have been used for this event. The need to avoid wake turbulence and make sufficient room in the pattern to accommodate such an aircraft had to be a pain to manage.
Regardless, excellent achievement in a cool aircraft.
According to the Bronze Age Greek calendar, yeah, that sounds about right.
Ezekiel 23:20
with no expense beyond the purchase price
As in, requiring no maintenance? Good luck waiting for *that* day in the aerospace industry.
Ezekiel 23:20
Could also be useful for spying - cloud cover can scupper satellites.
So you send a solar-powered drone to look below the cloud cover? Sounds logical.
Ezekiel 23:20
It left Phoenix Arizona May 22, 2013 and arrived at JFK 46 days later with a straight line distance of 2200 miles . That would be 47 miles per day. Sure there were a few stopovers but that is a very low daily mileage. Even if they flew one day in ten that is still only 470 miles per day.
I have a few questions for the makers of Solar Impulse;
1. How long does it stay on the ground charging the solar cells?
2. How often do they actually use the electric motor?
3. What percentage of time are they utilizing natural lift such as thermals and ridge lift?
I looked at their
web site
. It is a great PR site that give little or no technical information of the flight and how they are actually done. I would like to see the following;
1. Altitude logs for the flights,
2. Electric motor usage charts.
3. Battery charge level charts,
4. Exact track plots of the flights.
I bet we would have a very different picture of Solar Impulse if they let this information was let out.
It is my contention that Solar Impulse is a sailplane with enough electrical power to get to altitude and move between natural sources of lift. Conventional sailplanes can do almost everything that Solar Impulse does. The exception being taking off though there are some powered sailplanes that do that too.
Lets do a speed test to find the limits of the technology rather than a leisurely promotion trip. I am not impressed.
I read your comment and have been trying to understand what the issue is. This plane has flown at night before. It collects more solar energy during daytime flight than it uses for power and stores the remainder in batteries for use during nighttime flight. Even if it couldn't, this aircraft is quite slow so, it wouldn't outrun the sun in an east-to-west flight.
I think he means http://en.wikipedia.org/wiki/Jet_stream.
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I read your comment and have been trying to understand what the issue is. This plane has flown at night before. It collects more solar energy during daytime flight than it uses for power and stores the remainder in batteries for use during nighttime flight. Even if it couldn't, this aircraft is quite slow so, it wouldn't outrun the sun in an east-to-west flight.
Prevailing westerly winds? Most of the SF -> NYC trip would have been downwind. Most of an NYC -> SF trip would be upwind.
This article is about a night flight dine by Solar Impulse. Though they do not say it, I bet they started with 100% battery power. Here are a few interesting excerpts from the article.
. He remained at this altitude until about noon, flying backwards and forwards along the Jura mountain chain.
I am a glider pilot and this indicates that he is using ridge lift or mountain wave to stay alloft and/or gain altitude. Both are standard sailplane tactics.
After 14 ½ hours of flying, at 9:30pm, André Borschberg switched off the solar generator
Around midnight, the aircraft was at 4’500 feet, slightly less than 1’500 m, the altitude it needed to maintain until sunrise.
At 5:46am, on July 8, HB-SIA became the first solar-powered airplane to successfully complete a night flight.
By validating the fact that the HB-SIA had returned with a 54% charge level in its batteries,
So the aircraft consumed 46% of it's charge in about 5 hours and 46 minutes. Night was about 8 hours long. So they have proven that under controlled conditions with a very long day and a very short night the aircraft can fly overnight. Considering the sailplane record is 56 hours 15 Minutes, I am not impressed. It is still a toy with no practical application.
Or Google maps. Or a communications relay. Or a climate monitor. Or a weather monitor. etc.
The Wright Flyer wasn't all that practical either. No cargo, no passengers, one pilot, and less than 900 feet traveled.
One commenter mentioned the "fundamental dishonesty" of many of the stories on Solar Impulse. Hah. Even the Solar Impulse site itself acknowledges that a trans-USA flight in a series of hops was done by a previous airplane, Sunseeker. The year? 1990. Here's a photo of the plane: http://www.inhabitat.com/wp-content/uploads/sunseeker_solar_main.jpg
Wikipedia shows where Solar Impulse fits in the history of electric and solar-powered airplanes (it's pretty far down the list): http://en.wikipedia.org/wiki/Solar-powered_airplane
I have been astonished that so many "news" organizations were not all over the REAL story: latecomers trying to puff themselves up as "pioneers" and "innovators", when all of the pioneering and innovating in solar-powered airplanes was done decades previously. "Solar Challenger", anyone?
There is really very little room to improve such technology. The claims on the solar array are that their cells are roughly 22% efficient. The only way to really go up from there is with much more expensive multi-junction cells, and even then, you're going to top out at around 40%. Batteries could be improved, cutting weight and wingspan. Best case scenario, you might end up with something that could sustain 60mph, up from a mere 45mph. This will never be an alternative to the current batch of gas-guzzling technology.
The plane had to support the weight of the batteries and the solar cells. It had to be able to lift off and travel across the country so it could not rely on ridge lift for most sections of the flight. This same plane made it over night, all be it with the help of sailplane flying techniques. However, it is not, in fact, designed to be a sailplane nor does if function solely as one.
Well, the HINDENBURG filled with hydrogen lifted 480,000 lb including some 35,000 lb of engines plus 120,000 lb of fuel as well as the structural weight. With non flammable helium it would still have been over 400,000 lb, with large advances in structural materials since 1936 from which to save structural weight. Considering that it only required 3200 hp to fly 78 mph, and could have flown at 39 mph with only 400 hp, there's a helluva lot to spare for solar cells, electric motors, and batteries.
Yeah, I'd say tens of thousands of pounds is absolutely no stretch at all.
Significantly reduced expense might be more accurate.
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I think he's referring to the jet stream, which blows from West to East. That's the reason flights to the east are faster than flights to the west. The former benefits from a strong tail wind while the latter has to fly against a head wind. Flying from NYC to SF is going to be a lot more difficult.
There's a world of difference between "being able to fly a few hours at night when you're already aloft and using all tricks up the glider's sleeve" and "taking off, gaining altitude, navigating with a purpose to a specific target and staying over it when there's a prospect of overcast for a few whole days". It's the difference between a geeky experimental toy and mil-spec equipment that has to work no matter what the conditions are. Especially if you have to rely on the availability of the info the drone provides. I'm sorry, but in that role, hydrocarbons are really hard to beat.
Ezekiel 23:20
What an unfortunate attitude. When the Wright Flyer was demonstrated many militaries couldn't see what possible practical application the technology could ever have or how it could ever be advanced to a useful point. Same things happened with submarines and air-to-air missiles.
The first version usually isn't perfect, just like the first electric cars had some pretty major limitations. Even now some people can't accept that Tesla has made one that is absolutely fine for 95% of the population. It seems to be human nature.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
I think it more has to do with the ongoing superior energy density of hydrocarbons. Keep in mind that a) most portable energy storage mechanisms are limited by something proportional to chemical energy density, even physical energy storage methods like flywheels and b) hydrocarbons have the unusual property that they react with atmosphere and dump the reaction byproducts into atmosphere. There's a lot of mass saving that one can't get from batteries.
Actually, your comment neatly demonstrates the problem here. That is, even taking into consideration the fact that powering cars with electricity does have a whole load of benefits, the fact remains that the Wright brothers were flying their first flyer in exactly the period that was the heyday of electrical cars. So, fast forward one century, and unlike the Wrights' Flyer, electrical cars haven't exactly gotten off the ground, pardon the pun. We have one company that builds electrical cars that would be technically OK for most people, if the "most people" could afford them, and if there were a sufficient widespread infrastructure for handling them.
Oh, I'm pretty sure that in one more century, we'll have it down pat. Unless, you know, electrochemistry and the economy of building mobile energy storage devices stops us, that is. There's still a wide chasm between lab prototypes and stuff useful and economical enough for daily use. Electrical cars will most likely never replace hydrocarbon-fueled vehicles in some applications at least, and military drones are a similar kind of extreme application that simply won't budge to the "imagine how cool it would be" impulses that seem to be plaguing many a Slashdotter's mind.
Ezekiel 23:20