After developing some basic guidelines for designing liquid fueled launch vehicles, I noticed that it really all comes down to just a few easy to remember ratios.  Summarized, they are Second stage propellant mass ≈ 1 × payload mass Second stage dry mass ≈ 0.25 × propellant mass Second stage TWR ≈ 1.0 to 1.3 First stage propellant mass ≈ 2 × payload mass First stage dry mass ≈ 0.25 × propellant mass First stage TWR ≈ 1.3 to 1.5 In this case, payload mass refers to the total mas