That is pretty cool. Had no idea that steam engines powered planes, but it makes sense that the technology was tried. I'm guessing there were lots of people around in those days who could build and operate steam systems.

The 40 miles per gallon of water claim is kind of strange, because the water in this setup is turned to steam by burning oil- so that would have to factor into a true representation of mpg, but still neat.

I'm guessing maybe this is a representation of propulsive technology which would not scale up well for higher power requirements? Don't know, but thinking about the boiler size requirements for steam locomotives in the old railroad days leads me to believe the required apparatus would be too large for aviation use?