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Solar Impulse

by herpamad
Tags: impulse, solar
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D H
#19
Mar25-09, 07:46 PM
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Quote Quote by Cyrus View Post
The earlier derivative of Helios is pathfinder:

http://www.nasa.gov/centers/dryden/n...-034-DFRC.html
Pathfinder is an unmanned vehicle. There is a big, big difference between Pathfinder and Solar Impulse. Solar Impulse has to accommodate the extra weight of a pilot and operates at low altitudes, thus limiting performance.


Quote Quote by FredGarvin View Post
In their defense, they do appear to be making some parts (see the blog section). Who knows? Like I said, I wish them luck, but my BS meter is still registering.
My BS meter is similarly off-scale high.

In their defense, they are Europeans. From my albeit limited experience with European projects, Europeans have taken the silly US concept of vugraph engineering to the nth degree. In the US, a website like that would be a sign of all fluff, no stuff. In Europe, a startup without all that fluff is a sign of a project in trouble.
Cyrus
#20
Mar25-09, 08:54 PM
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Quote Quote by D H View Post
Pathfinder is an unmanned vehicle. There is a big, big difference between Pathfinder and Solar Impulse. Solar Impulse has to accommodate the extra weight of a pilot and operates at low altitudes, thus limiting performance.



My BS meter is similarly off-scale high.

In their defense, they are Europeans. From my albeit limited experience with European projects, Europeans have taken the silly US concept of vugraph engineering to the nth degree. In the US, a website like that would be a sign of all fluff, no stuff. In Europe, a startup without all that fluff is a sign of a project in trouble.
The solar cells on the pathfinder provided roughly 10HP. This is more than enough to power flight of a person. A HPA uses roughly 300watts, and flies at low altitude.

http://en.wikipedia.org/wiki/File:Da...d-aircraft.jpg

There's no reason why you cant get off the ground with a person using the power of the Pathfinder.
herpamad
#21
Mar26-09, 12:06 PM
P: 81
I cant remember the exact power required, but one of the HPA project said how many watts was needed to maintain level flight.

It was the same as riding a bike on the flat at 20kph, but i cant seem to find the power...

But like said, its been done on a UAV scale, and its been done using a glider and HPA.

Getting a solar powered aircraft airborne is not the "big" issue here for me.

Its how is it going to stay up for around 6 weeks. More to the point, how will it stay airborne for 36 hours taking into account the weight of the batterys.

I also think its a pretty heavy machine, i read somewhere that the weight is close to 2t.

I posted the link to the glider, so it can be done as it has been done, and wikipedia also has the HPA that was converted to solar.

So to me the challenge is "endurance" and thats what i am trying to focus my study on, keeping it in the air for at least 36 hours with some failsafe options, maybe 4 hours extra power.

I have read some place about a solar para-motor that drags the solar cells behind it, and a blimp covered in solar cells, looks like solar is the future...
Cyrus
#22
Mar26-09, 12:32 PM
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P: 4,780
Quote Quote by herpamad View Post
I cant remember the exact power required, but one of the HPA project said how many watts was needed to maintain level flight.

It was the same as riding a bike on the flat at 20kph, but i cant seem to find the power...

But like said, its been done on a UAV scale, and its been done using a glider and HPA.

Getting a solar powered aircraft airborne is not the "big" issue here for me.

Its how is it going to stay up for around 6 weeks. More to the point, how will it stay airborne for 36 hours taking into account the weight of the batterys.

I also think its a pretty heavy machine, i read somewhere that the weight is close to 2t.

I posted the link to the glider, so it can be done as it has been done, and wikipedia also has the HPA that was converted to solar.

So to me the challenge is "endurance" and thats what i am trying to focus my study on, keeping it in the air for at least 36 hours with some failsafe options, maybe 4 hours extra power.

I have read some place about a solar para-motor that drags the solar cells behind it, and a blimp covered in solar cells, looks like solar is the future...
I don't agree with that statement.
herpamad
#23
Mar29-09, 06:06 AM
P: 81
Well neither do i when i think about it.

As my real thoughts are that Hydrogen and Biofuels may power aircraft of the future, even though they are powering aircraft of today in small trials.

I would like to think that solar has its uses in static based applications, and that hydro and wind power will have its place in static applications too.

However, in a UAV setting, i think solar can offer some great possibilities for endurance.


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