solar powered UAV flies forever

[spikeyhead]

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

[Silver993tt]

spikeyhead said:

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

what happens in winter when there's alot less sunshine available, especially beyond certain latitudes in the north & south hemispheres (e.g Europe or further north)? Less daylight hours and sun at a more accute angle will provide far less energy.

[AnotherClarkey]

Silver993tt said:

spikeyhead said:

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

what happens in winter when there's alot less sunshine available, especially beyond certain latitudes in the north & south hemispheres (e.g Europe or further north)? Less daylight hours and sun at a more accute angle will provide far less energy.

Maybe it flies south for the winter? We could have flocks of migrating perpetual UAV's constantly roaming the planet.

[Silver993tt]

AnotherClarkey said:

Silver993tt said:

spikeyhead said:

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

what happens in winter when there's alot less sunshine available, especially beyond certain latitudes in the north & south hemispheres (e.g Europe or further north)? Less daylight hours and sun at a more accute angle will provide far less energy.

Maybe it flies south for the winter? We could have flocks of migrating perpetual UAV's constantly roaming the planet.

That's no good if they need to monitor criminals/terrorists though. These people don't stop their business in winter.

[Eric Mc]

Silver993tt said:

AnotherClarkey said:

Silver993tt said:

spikeyhead said:

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

what happens in winter when there's alot less sunshine available, especially beyond certain latitudes in the north & south hemispheres (e.g Europe or further north)? Less daylight hours and sun at a more accute angle will provide far less energy.

Maybe it flies south for the winter? We could have flocks of migrating perpetual UAV's constantly roaming the planet.

That's no good if they need to monitor criminals/terrorists though. These people don't stop their business in winter.

And they often do their work in the dark.

[Silver993tt]

Eric Mc said:

Silver993tt said:

AnotherClarkey said:

Silver993tt said:

spikeyhead said:

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

what happens in winter when there's alot less sunshine available, especially beyond certain latitudes in the north & south hemispheres (e.g Europe or further north)? Less daylight hours and sun at a more accute angle will provide far less energy.

Maybe it flies south for the winter? We could have flocks of migrating perpetual UAV's constantly roaming the planet.

That's no good if they need to monitor criminals/terrorists though. These people don't stop their business in winter.

And they often do their work in the dark.

Maybe they could fit them with a giant carbon fibre magnifying glass to use moonlight

[AnotherClarkey]

Eric Mc said:

Silver993tt said:

AnotherClarkey said:

Silver993tt said:

spikeyhead said:

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

what happens in winter when there's alot less sunshine available, especially beyond certain latitudes in the north & south hemispheres (e.g Europe or further north)? Less daylight hours and sun at a more accute angle will provide far less energy.

Maybe it flies south for the winter? We could have flocks of migrating perpetual UAV's constantly roaming the planet.

That's no good if they need to monitor criminals/terrorists though. These people don't stop their business in winter.

And they often do their work in the dark.

Yes, but it stays airborne all night anyway.

[Eric Mc]

On board batteries.

But I bet its systems are powered down (like the Martian Rovers) during the hours of darkness.

[Silver993tt]

AnotherClarkey said:

Eric Mc said:

Silver993tt said:

AnotherClarkey said:

Silver993tt said:

spikeyhead said:

well, not quite forever, but it did manage 336 hours non-stop flight.

http://www.bbc.co.uk/news/science-environment-1207...

what happens in winter when there's alot less sunshine available, especially beyond certain latitudes in the north & south hemispheres (e.g Europe or further north)? Less daylight hours and sun at a more accute angle will provide far less energy.

Maybe it flies south for the winter? We could have flocks of migrating perpetual UAV's constantly roaming the planet.

That's no good if they need to monitor criminals/terrorists though. These people don't stop their business in winter.

And they often do their work in the dark.

Yes, but it stays airborne all night anyway.

the tests have taken place where the sun is up for most of the day. In areas where the sun is only up for a few hours and is at an accute angle, the batteries won't be charged enough for a winter's long night. I suppose at some point batteries will be developed that overcome the problem.

[Talksteer]

This partially ties in with DARPA's Vulture project, an interesting artical here.

http://www.flightglobal.com/articles/2009/11/30/33...

The DARPA project is looking at being able to opperate at the winter solstice as far north as 45 degrees which is about the same lattitude as Bordeux. For military purposes 45 degrees either side of the equator covers pretty much all of the worlds combat zones wouldn't quite be there for providing broadband to rural Scotland though.

The higher you opperate the UAV the more hours of sunlight you get and also the further any transmissions can be sent. If DARPA were assuming an observation mission at 45 degrees north and at 65,000 ft a UAV at 120,000ft would be able to fly 200km further north and project signals 650km further north of that point. This would get you to Rotherham within the vulture's technical specs. You might be able to do a bit more with a lighter aircraft that is more able to fly on its side to collect those last few mintues of solar radiation.