Interesting. I'm surprised I didn't hear that solution mentioned in Bill Gates "How to Avoid a Climate Disaster" book.

He basically made the same battery weight argument and was pushing for alternative biofuels for planes, if I remember correctly. And that was just published earlier this year, and seemed pretty comprehensive about discussing all possible solutions, at least as far as I could tell.

Maybe just because it's (presumably) nowhere near the point where it could be feasible for commercial passenger planes?