[Spaceships] Black powder Rockets?

[Marasmusine]

Originally Posted by Agemegos

Bear in mind that in GURPS Spaceships' terms the model rocket motors you buy consist of a engine and some fuel tanks, not just an engine. Listed thrust-to-weight ratios in the spec will be for the fully-fuelled motor at ignition, not for the almost-empty motor at flameout.

I see, thanks. I'm now looking at http://www2.estesrockets.com/pdf/Estes_Engine_Chart.pdf which shows initial weight and propellant weight. It looks like, roughly speaking in Spaceships terms, half the components would be chemical rocket, and half would be fuel tanks.