[Spaceships] simply fuel math...

[Anthony]

Originally Posted by hal

Formula for Delta-V is .003 x Isp x Ln(Loaded Mass/Dry Mass)

Formula for delta-V is ISp * ln( loaded/dry ). However, if ISp and delta-V are not in the same units, you need a conversion factor. ISp has historically been described in pound-seconds per pound (where the first pound is a lb force, the second pound is a lb mass), or just Seconds.

The conversion from Seconds to mps is ~0.0061 mps/Second, I don't know where you're getting 0.003 from.