#SSTO isn't completely dead as an idea, BTW -- there is still #Skylon .

Not sure what their status is at this point, but definitely NOT flying anything yet.

I'd love to see that one work out, but I'm not holding my breath.

https://en.wikipedia.org/wiki/Skylon_(spacecraft)

[...]

Now for a LONG time, the holy grail of space development was a "Single Stage To Orbit" vehicle ( #SSTO ). But no one has been able to make this concept work.

And there is some question if actually doing it would require such an expensive design that it wouldn't actually be the payoff we hoped for.

https://en.wikipedia.org/wiki/Single-stage-to-orbit

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@arstechnica Jan 19, 2022 #Radian announces to build a #SSTO #spaceplane ✈️ which could lift five people 👨‍🚀 and 5,000 pounds of #cargo 📦 into #orbit 🌎 https://arstechnica.com/science/2022/01/radian-announces-plans-to-build-one-of-the-holy-grails-of-spaceflight

Picture : #VentureStar single-stage-to-orbit spaceplane size comparison https://en.wikipedia.org/wiki/VentureStar