If men could design enough energy output from solar, already mankind would have solar planes. So why hold these impractical flights?
There is but one reason: persuasion-in-propaganda. These solar stunts are mere propaganda to reinforce false beliefs in Gaia worshiping misanthropes.
It's not as if aviation is in its infancy. Engineers understand the mechanics of flight well. Engineers know already how much energy they need to achieve thrust and sustained powered flight.
Engineers can be on the ground trying to get solar output up to what is needed to haul 300 passengers of a conventional long-haul passenger flight. Engineers don't need these test flights.
The propagandists working for Solar Impulse claim they are "voyaging around the world without fuel or pollution." Likely, that is a huge lie.
So the manufacturing of the batteries happened without any pollution? So the construction of the airplane, built from special carbon fibers happened without any pollution? So the electric motors were manufactured without any pollution?
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