On 2003-01-29 11:45, Anonymous wrote:
Tubes are aerodynamic katastrophe.... would like to see one compared to a foil in wind channels... why dont the paragliders use tube style gliders... .. the future will be foils believe it or not...
Armin Harich does a great Job out there and paraglider manufacturers come up with great kites in the future...
This is a common misconception !
I will not defend neither foils nor LEI's, but LEI's are extremely well performing aerodynamically.
And you cant compare to a paraglider - which has to be soft for other practical reasons.
If you take an older style hangglider, with a thick round front aluminium pipe as LE, and single skin - it will still outperform most paragliders in terms of L/D and sink speed.
And in windsurfing, the double surface has so little, or no advantage, and so many drawbacks, that it is not used any more (it was in the past).
And there are other aerodynamic advantages of the LEI shape for kitesurfing, which does not exist in paragliding terms.
But it is like comparing apples to oranges...
The foil is excellent aerodynamically, but the LEI is excellent performing too.
These are simple facts, and the reason why there is so much nagging and biting and hardly any REAL discussion now.