Ramjet

It may seem like a horse-drawn Zeppelin, but Astro Mechanica seems to be all-in on its revolutionary hybrid-electric supersonic jet engine as it partnered with UK-based engineering firm Helix to add high-energy density radial-flux motors to the tech.

Tiberius Aerospace's Sceptre TRBM 155HG 155mm artillery round has a ramjet in its nose that allows it to fly at supersonic speeds and gives it over four times the range of a conventional round.