Why does nobody use Liquid-Propellant rockets?

Thunderbolt said:

The fuel container is printed plastic and is also consumed as fuel. The exact internal workings have not been fully described.

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In essence then it’s a hybrid with added liquid fuel. (That’s an oversimplification, maybe even inaccurate, and I realize it.)
Several years ago a “tribrid” motor was approved for use at Tripoli launches. It was a hybrid with added liquid fuel.

The hybrid mode was brief. It served the purpose of getting combustion going and up to pressure before introduction of liquid fuel. This avoided hard start issues.

Gerald

Was it difficult to get the motor certified? How was the liquid injected? I wonder about producing a simple liquid motor. In careless hands, this could be quite dangerous. But if done well, it could be quite exciting to add liquid motors to an HPR launch.

awseiger said:

Why does nobody use Liquid Propellant rocket motors? ?

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Because having ten fingers is awesome.

DavidMcCann said:

Because having ten fingers is awesome.

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X10
The closest configuration akin to liquid propellant I want is my Contrail M- hybrid, no liquid propellant, just the oxidizer that's pretty funny!

Lots of people use liquid propellants. SpaceX, Ariane, ULA, Blue Origin, Soyuz...........
Oh, amateurs....

• Fuel and oxidizer can be really nasty stuff
• Cost
• Fuel and oxidizer can be really nasty stuff
• Complexity
• Fuel and oxidizer can be really nasty stuff
• Cryogenics
• Fuel and oxidizer can be really nasty stuff
• If you fuel up and decide not to launch, then what?
• Fuel and oxidizer can be really nasty stuff

The discussion was revived by new member Thunderbolt.

It is an interesting discussion nonetheless

Systeme Solaire, a Canadian company, I think, has been around since the mid 80's, and promotes their liquid fueled motor.
https://pages.total.net/~launch/ss67b3.htm

My understanding, fourth hand, was that it was (is) difficult to launch successfully.

-Mike

The GSE requirements are pretty heinous. Lowest I can come up with is at least a trailersworth.

mdnehez said:

Systeme Solaire, a Canadian company, I think, has been around since the mid 80's, and promotes their liquid fueled motor.
https://pages.total.net/~launch/ss67b3.htm

My understanding, fourth hand, was that it was (is) difficult to launch successfully.

-Mike

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The engine itself doesn’t even manage a 4:1 thrust to weight ratio. Once a rocket has been added to carry it you’d need a very long rail or active stabilization.

and it's $1100 for a J motor....spendy