Posted on 04/22/2016 1:15:45 AM PDT by nickcarraway
Extreme long duration, extreme high altitude powered flight.
Don't let your mind get stuck in a rut of bombers, fighters, freighters, and passenger aircraft.
Instead, think about what you might do with a (possibly unmanned) aircraft that can fly for days or weeks without landing or aerial refueling.
How much of their energy is solar and how much is batteries that have been charged off the grid?
I’ve got to admit, you’re right on that score.
I hope it floats.
It is also somewhat misleading to say they took off “without fuel” if they took off with charged batteries, as electricity is the fuel of electric motors.
That said, it’s quite possible they took off with discharged batteries, and will charge them for the night flight during the previous day, but I doubt it.
I’m sure they feel a touch of panic when the sun sets. That will make for a long night, running on batteries and gliding on a managed descent until sunrise.
It is my understanding that when they race those solar cars in Australia, that is exactly what they do. The batteries must be charged by the sun for some time prior to the race.
I think that is really a non-issue. If they have the ability to fully charge the batteries from sitting in sunlight, then what difference does it make if they do it that way versus charging them up the other way?
The difference to me is when they say they “took off without fuel.” Suppose there were a machine that used sunlight to turn air into aviation fuel, say, by using the carbon from carbon dioxide in the air, and hydrogen from the water vapor in air. If that machine were on board, and churning out gas as the plane was prepped for the flight, I don’t think one could claim that the plane “took off without fuel”, even if the tanks were empty earlier. So it is with batteries and electric motors: batteries simply store the chemical energy in a different way, e.g. as lithium metal or lead dioxide, instead of gasoline, and you get the energy out as electricity instead of as combustion. Maybe what they mean is “without any combustible fuel” but I think that is misleading and therefore deceptive.
Yeah, I suspect they wouldn’t get in it if there is a possibility it would run out of air at night!
Still, at 100,000 feet on a cloudy night and day, how far would they drop?
The plane that got to 100,000 feet was unmanned. They'd have to wear space suits to be that high and they don't have the power to haul all the necessary life support equipment. Also the wings were a lot longer on the 100,000 plane.
Amelia Earhart also departed successfully.
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