Russia's Liquid Love Affair; or why Russia seems to avoid solid rockets

[Budgie]

So I'm definitely no historian, but in reading into the history and seeing the various rockets produced by Russia/USSR, I've noticed that solid rockets in large sizes (Think SSRB or the ones mounted on Titan rockets) have never been used as booster stages. It seems that Russia barely touches solid fuel at all. Is there a reason for this, or is this just one of the characteristics of two space programs developing independently?

[xenomorph555]

You made a correct observation, that Russia primarily use liquid for everything, however the reasons are various and complex.

It comes down to difficultys in the technology at the time and pseudo-cultural/historical views of scientists and engineers who, back then and still do, prefer to work with liquid rockets. They began working on liquid tech and instead of abandoning it strived to perfect it.

[Captain Sierra]

You made a correct observation, that Russia primarily use liquid for everything, however the reasons are various and complex.

It comes down to difficultys in the technology at the time and pseudo-cultural/historical views of scientists and engineers who, back then and still do, prefer to work with liquid rockets. They began working on liquid tech and instead of abandoning it strived to perfect it.

I'll also point out the multiple times we've had SRBs blow up on us. Russia may be onto something ...

[xenomorph555]

Should also point out that these days Russia uses solid rockets immensely, just not for SLV's. Examples include the Topol or the R-39.

[Sampa]

the reason behind that is simple, solid fuel cannot be controlled, which they found to their dismay!

[mrfox]

Its safer. Solid rockets are just cheap. Its basically a big firecracker that once lit, cannot be extinguished.

Still find it unbelievable that anyone would launch manned missions with it.

[Nothalogh]

Everyone can build a crappy solid rocket, but it takes some real engineering wizardry to come up with a reliable high performance solid rocket like the Minuteman uses.

The Soviets stuck with their Hypergolic liquid designs, which as long as you're not too concerned about safety, are quite economical on the logistics side, are storable fueled, and have very good performance.

[magnemoe]

Everyone can build a crappy solid rocket, but it takes some real engineering wizardry to come up with a reliable high performance solid rocket like the Minuteman uses.

The Soviets stuck with their Hypergolic liquid designs, which as long as you're not too concerned about safety, are quite economical on the logistics side, are storable fueled, and have very good performance.

Googled and found that minuteman 2 uses an RC class probe core

https://en.wikipedia.org/wiki/LGM-30_Minuteman#/media/File:Minuteman_guidance_computer_(1).jpg

Russia has some solid fuel ICBM and moving in that direction.

[lajoswinkler]

One of the rare things they do right. I'd rather ride a Soyuz than a Space Shuttle or any other SRB-powered vehicle.

[Nibb31]

Solids being cheap is a common misconception. Although the basic design is simple, designing the internal cavities of a solid booster is a complex business. The solid fuel grain has to be custom-shaped so that the combustion follows a specific burn profile depending on the launch requirements.

As you can see, those grain shapes aren't exactly intuitive, and it took lots of trial and error to figure them out. This means that it was much harder to repurpose a solid booster for different missions. Both the US and Soviet space program were originally designed with repurposed ICBMs, and those early ICBMs were all liquid-based, because it gave better control of the flight profile, which meant greater precision.

Later on, both nations switched to solid ICBMs, because they can be launched instantly, whereas the old liquid ICBMs required a long fueling and preparation time before being launched.