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Solar Impulse Announces Flight Across America For 2013
cylonlover writes "Flush with success from their 6,000-km (3,728-mile) Europe-to-Africa round-trip flight earlier this year, the duo behind the Solar Impulse solar-powered aircraft are now planning on flying it across America next spring. It will mark the first time that a solar-powered plane has traversed the country. Solar Impulse partners Bertrand Piccard and André Borschberg made the official announcement this Tuesday, although the logistics of the flight have yet to be finalized. They have stated that the trip will be broken into 20-hour legs, starting at San Francisco and proceeding to New York City. As with their previous multi-leg flights, the two pilots will take turns flying the aircraft." You can read about it straight from the doers, too.
it's been raining here.
Be seeing you...
This is obviously a prototype, but I wonder cheap you could make an operational system? Fuel costs are the the largest component of an aircraft's operating costs, and the most variable. Relatively slow (~100 mph) solar UAVs could make a lot of sense for UPS, FedEx, etc.
Same thing could be said about the first rocket flight...however, look where it got us
Wind or geothermal would be much better.
I wish they would check their facts before claiming the first solar flight across the US. In 1990 Eric Raymond flew his Sunseeker solar powered airplane across the US from west to east coast (with multiple stops), but nevertheless 22 years ago. His latest effort is a two place advanced solar powered airplane based on a custom Stemme sailplane fuselage with solar wing and empennage, called Sunseeker Duo. His website is www.solar-flight.com
No they didn't. They flew mostly during the day. Notice the flight was May to July during the longer days of the year. They also spent a significant time gaining altitude using thermals and local lift conditions to conserve battery power. Evidence if this is quote from the Africa trip article.
On its final leg from Toulouse to Payerne, Solar Impulse traveled 615 km (382 miles) in 13 hours 29 minutes at an average speed of 63 km/h (39 mph) and at an average altitude of 3,596 meters (11,800 ft).
If the average speed was 63 km/h and it flew for 13.5 hours it should have gone 850km. Since the distance is only 615 km, where did the other 235 km go? That is almost 28% of the movement. They went to spiraling in thermals and searching for other form of lift to conserve power. It's real average speed if measured as progress toward its destination is closer to 45 km/h. Sorry but Solar Impulse is not an electric powered aircraft. It is a high performance sailplane with a very expensive electric motor to help it get from lift condition to lift condition. It's real average speed if measured as progress toward its destination is closer to 45 km/h.
If you want to impress me do it in November-December in the Northern Hemisphere and fly in a straight line.
Neither does that plane.
Whilst impressive, we've gone a bit backwards in recent years, it was 1986 when the first aircraft successfully flew around the world, non stop, no refueling. http://en.wikipedia.org/wiki/Rutan_Voyager
Call me old, but I miss the old days when we use to circumnavigate the globe, travel to the moon, send probes to Pluto and Neptune.
You are missing the point. Their objective is not to to develop a practical solar aircraft but to circumnavigate the globe with one.
Thus their plane only has to be good enough for that purpose. In particular it doesn't matter if it can't fly during the winter solstice or if it is slow.
Note also that aggressively exploiting currents and thermals was already a key part of the strategy of Breitling Orbiter 3, from some of the same people.
A electric, solar no less, plane traveling around the globe nonstop will be a fantastic achievement!
Agreed, the point is that these people have not even flown 15 hours nonstop. Notice that they keep referring to 20 hour legs with two pilots? Add that to the fact that it is a single pilot aircraft means that they land at least once a leg. They have also never flown across a large body of water. Saying that this technology will make a nonstop flight around the world is like showing a dragster and saying it can be used to get from LA to New York really fast.
The main obstacle is that there is very little, if any, lift over oceans. Lift is caused by differences in the land surface, materials, mountains etc. There are no stable differences on the ocean surface and therefore no lift.
The circumference of the earth is about 2200km. Divide that by the 45km/h speed and you get 19 days. That is a lot of supplies including oxygen, which will be needed above 10000ft, to be carried on a light sailplane. Noter they flew at an average of 11,800 ft on their first trek.
Another point is that sailplanes already do better than this aircraft under similar conditions. This pilot already went three times the distance of one of their legs in a sailplane with no motor at all.
They have a long way to go before any of their long distance goals will be reached.
hahahaha, do you realize how paltry the power generated would be compared to the output of the jet engines? The cabin electrical nees are essentially zero in a jumbo jet, compared to the tens of megawatts output of the engines. there is no point, no meaningful percentage of fuel saved