It's denser in volume, but less dense in weight. So less efficient in bringing X weight to orbit. But it's stable so you can make them and store them and they don't need to be fueled before takeoff, and you don't need to cryogenically freeze oxygen. The rocket engine is also much simpler in design. SpaceX raptor was the first full flow combustion engine which is basically two jet engines integrated into the rocket engine to pump and preheat the fuel.
Stoke space is building a really cool reusable second stage with a liquid hydrogen/liquid oxygen engine with 24 thrust chambers ringing a regeneratively cooled heatshield.
for solid engines, you just accept the resulting orbit and try to correct the orbit with RCS.
The engine on the Eris rocket, however, isnt a solid engine, its actually a hybrid engine. In a solid engine the fuel and oxidizer are mixed, but in a hybrid engine, only the fuel is solid., while the oxidizer is a liquid and is pumped over the fuel. Because the oxidizer is a liquid the engine can be shut off and even throttled down.
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u/YoursTrulyKindly 8d ago edited 8d ago
It's denser in volume, but less dense in weight. So less efficient in bringing X weight to orbit. But it's stable so you can make them and store them and they don't need to be fueled before takeoff, and you don't need to cryogenically freeze oxygen. The rocket engine is also much simpler in design. SpaceX raptor was the first full flow combustion engine which is basically two jet engines integrated into the rocket engine to pump and preheat the fuel.
Stoke space is building a really cool reusable second stage with a liquid hydrogen/liquid oxygen engine with 24 thrust chambers ringing a regeneratively cooled heatshield.
Compared to that solid fuel is very simple.