Ramming speed ja?
imagine its 1946 and for whatever macguffin' the war is still on/the mustache man hasn’t ventilated his own skull yet, and you're a B-17 ball gunner over Germany and last thing you see some gunless pacifist, aka 'The Desperation Dorito', flying right through your ass.
The designer of this monstrosity, Alexander Lippisch, is really fascinating. He pioneered the use of canards, rocket propulsion and delta fuselages and was researching supersonic flight during WWII. When it was clear that the war was lost, he kept his students working on crazy ideas to keep them from getting drafted.
Oh those crazy Nazis...
You actually can run just about anything that takes gas or vapour fuel on coal/charcoal, by burning a bit of it in very air-poor conditions so it forms carbon monoxide. Carbon monoxide is flammable.
The problem being that since the coal is half burned by the time it's actually in the ramjet, it doesn't have great energy density. For a car or generator that's fine, but for powered flight...