One of Stine's paid research gig's involved using Coanda nozzle ram jets for submarine propulsionBy "compressed air" they don't mean a pressure tank. It's the same as a compressor on a turbo jet. Spinning blades.
Analog has been an American Science Fiction/Science Fact magazine since the late 1940s? I have issues from 1953, when it was titled Astounding. Some of the best SF ever, Dune, Dragonsinger, etc. And the Fact articles run towards the cutting edge. They were talking this stuff in the 1960s.
You want REAL Propless? Electric plasma magnetically accelerated instead of a ducted fan... Over to You, Henryk!