>>602494
>Name one example. Even a proposal.
Gnom was rumored to be the original test vehicle but Soviet records are pretty fucking secret. RVV-AE-PD uses exactly this technology, it's not in service yet but I think tests have been carried out.
I am unsure if Izdeliye 172 was featured with this technology, I once saw a plastic mockup that was, but current variants of the missile look different. Of course they're pajeet contracted, so its half the range of what it used to be due to international treaties.
Over in America, FVRAAM (pictured) had something it called a "hybrid ramjet" motor. Since airbreathing rockets are basically a ramjet engine that gets pressurized by rocket exhaust…. "hybrid" is a good descriptor.
I'm unsure of the design so I can't comment, but I still believe it was an attempt to get at this tech. Meteor might also have it.
>The british HOTOL program(now skylon)
Is not an airbreathing rocket, it's a precooled jet engine.
At high altitude air loses density, which makes using jet engine impossible. However Skylon uses an amazing precooler to concentrate high altitude rarified air coming into the intake, into something a jet engine can use to combust fuel for thrust.
Once hit hits a certain altitude I think it still has to convert to regular rocket, because it carries a small O2 tank as well.
Airbreathing rockets can't travel as high as skylon, it's just a way to reduce the oxygen (or oxidizer) needed at lower altitudes.