Source Material

[nathanielbuildsatesseract]

I think I figured out where the propulsion engineers were getting the weird flight performance equations I complained about in Reconcilable Differences. Specifically, I'm finding very similar forms of the equations in a NASA translation of Walter Hohmann's The Attainability of Heavenly Bodies, which laid out many of the equations for designing interplanetary space missions.

I'm glad that I found where they were coming from (probably), but I'm still a little bothered, because these forms of the equations aren't really the best to work with. They made a lot of sense in the 1920s and 30s, when astronautics was still an embryonic art. They don't make much sense now, when all the tabulated values one would need for the friendlier forms are available from textbooks or Wikipedia.

To me, this implies a necessity of distancing ourselves from technical source materials, of improving on it whenever possible. The challenge is that the reasons for a particular formulation are not always stated clearly, introducing uncertainties about whether a particular adaptation is valid. Avoiding this, as I have stated, is one of the major goals of my own technical writing. If only industry-standard textbooks took the same care!