Two years ago around this time, this blog was mooting aeroplane thrusters (over Venus). We learnt (eventually) that the propeller-fan(s) required a LOT of energy to move, more than a battery might supply. Boeing's engines are a mix of fuel and fan. Although propeller-only flights by battery are (as of mid 2020) possible they are not feasible.
ToughSf notes that NASA has been on this beat since 2009: distributing the fans from the jet (pdf). The fans sit in the centre of the craft. The generators run out on the wingtips. This allows the overall craft to be a more perfect aerofoil. They call it "TeDP".
It's awesome. So why don't we do it? Because the fans need energy, and if we're importing that energy they need conductivity with the least ohms. This turns out to be an unobtanium in flight, even high-altitude flight... unless we use a (sigh) superconductor. They wanted under 10 μm filament diameter.
For propellant they started with LH2 but they don't demand that, so methane might do it.
In 2009 they pondered, for the superconductor, MgB2 against the usual rebco. (Although any of these require some major coolants.) Over the following six years NASA explored this studio space and came up with the N3-X (pdf). It was preferred to use bisco. Here's where they were at in 2017 (pdf): Rolls-Royce and some other companies are actively doing this research.
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