Isn't it lighter than air? The article also claims its heavier, but I assumed it was a mistake.
Re:Solar powered airships
by TelmoMenezes on Sunday October 23, 2011 @12:37PM
(#3146495)
Heavier. The article is about an hybrid vessel that uses helium to decrease its weight but is still heavier than air. I'm not a physicist, but I assume that lighter than air objects tend to have more wind resistance than heavier than air objects.
> lighter than air objects tend to have more wind resistance than heavier than air objects.
They have a larger cross-section relative to their mass than heavier than air vehicles. The larger the cross-section, the larger the force wind exerts on it.
Oh, I get it now.
Re:Solar powered airships
by SagelyGuru on Sunday October 23, 2011 @12:47PM
(#3146523)
The idea of heavier than air but lighter than deadweight seems to be a worthy compromise to explore but of course, if the engines fail or it runs out of sunshine/fuel, it will not be able to stay up very long, just like any other heavier-than-air aircraft.
Lest anyone brings up skilled gliders, I don't think with its wind-resistance this craft will glide for long either.
It can be a lot more problematic 'beating upwind' the other way, especially as there is not much sunshine in northern Europe due to its considerable latitude.
This craft may be heavier than air but it still has considerable wind resistance.
Also, the dangerous static electricity buildup has to be considered seriously and solved.