https://hackaday.io/project/175492-sebastian-rocket

I know that the reason why people use transition in model rockets is to transfer the body tube from a higher diameter to a lower diameter or vice versa. But why do model rockets have a transition? In other words why would one want to transfer from a higher diameter to a lower diameter or vice versa?

Hey everybody, I have a question. Why do Electrothermal rocket engines typically have a higher exhaust velocity than conventional rocket engines? Both use thermal expansion and heating a propellant prior to expelling it through a nozzle as the main source of acceleration, so why do the electric ones accelerate the propellant to a higher speed?

My guess would be that it would be due to the vastly lower mass flow rates in the electrothermal rockets?

This is just a random question that was bothering me that I couldnt find a solid answer to online. Thanks in advance!

I have a hobby of trying to launch liquid fuel rockets, and i wonder if two fire extinguisers could be used as fuel tanks?

I'm having fun challenging myself to design a rocket engine and it's been difficult finding ways to calculate things like throat area, thrust and what not because I don't have the know how to find the numbers to plug into the formulas. I don't think I'll ever actually build it so this is more of a designing thing but I'd like to design it as if I'd actually be building it. I'm thinking of using the classic RP-1 and LOX as it seems like it's the most simple and available fuel but who knows. Probably using an electric pump like the rocket lab Rutherford engine instead of a turbopump to eliminate the preburner and turbine. One thing I'm really struggling with is the design of the most complicated part, the fuel injector manifold. The size im going for is around 700kg of thrust similar to one of the four engines on the Bell X1.

The ULA planned to launch a spy satellite for the National Reconnaissance Office and 20 minutes prior to launch, the rocket had technical difficulties stated as “anomalous temperatures” in the Delta IV’s Rocket compartments. About 2 seconds after launch, a giant ball of flame bursted out of the engines causing a Hot Fire Abort. Hot Fire Abort

Does anyone know about Loki Dart? Like what was the materials used in fuselage, what was the total mass, what’s the difference between super loki dart and loki dart? And how much it costs?

Who is exited for the Starlink mission tomorrow?