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Solar planes are not the future of flight

empiricalzeal.com

1–10 of 18 posts

Re: Solar planes are not the future of flight

#5

>The plane isn’t going to run out of juice, unless it meets some clouds or some serious tailwind. Why would a tailwind matter? That would cause it to go faster relative to the ground, but it shouldn't matter in terms of lift, right?

An airfoil (wing) creates lift when air flows from the leading edge to the trailing edge, and the speed of this airflow is one of the factors which determine how much lift is generated. A strong tailwind will interrupt the airflow, induce turbulence and decrease lift. Thus, an airfoil moving into a headwind will generate greater lift than one moving through a tailwind.

Re: Solar planes are not the future of flight

#6

Why not fill the wings with helium or other lighter than air solid. ~Lift increases by the cube, weight by the square. I'm waiting for someone to invent an extremely cheap lighter than air solid which can act like a battery.

> Lighter than air solid

Is this even possible at normal temperature? I can't imagine this at 1 atm. and room temperature...

after some googl-ing:

http://en.wikipedia.org/wiki/Aerogel

Re: Solar planes are not the future of flight

#9

Why not fill the wings with helium or other lighter than air solid. ~Lift increases by the cube, weight by the square. I'm waiting for someone to invent an extremely cheap lighter than air solid which can act like a battery.

The amount of lift you would get from such a small amount of helium would be practically negligible compared to the weight of the aircraft. Lighter-than-air craft require an enormous volume of helium/hydrogen - due to the cross-section of such a craft, the speed of travel is severely limited by drag. Basically, an aircraft uses wings OR lighter-than-air gas - it can't use both.
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