Reconcilable Differences

[nathanielbuildsatesseract]

One of the interesting things about reading technical books written by multiple authors over subsequent editions (and/or featuring chapters contributed by other authors) is seeing the different ways that people in different subdisciplines approach matters. On the whole, it's not a particularly pleasant experience, because one field will have optimized their approach, and then writers in a different field will try to simplify or restate things in a less-efficient or less-clear matter.

For a concrete example, I'm reading Rocket Propulsion Elements right now, which is considered one of the seminal texts on chemical rockets. I had run into this phenomena before, but propulsion engineers have some truly mystifying ideas about astrodynamics. The "Flight Performance" chapter uses absolutely butchered equations for two-body motion, and in English units of all things! The standard versions that show up in Orbital Mechanics materials are more intuitive, computationally easier, and generally use kilometers instead of feet.

Meanwhile, the chapter on electric propulsion introduces a whole new set of performance parameters. I think these parameters make sense for ion engines and the like, but are less helpful for impulsive transfers. This example is less frustrating and more interesting, because it highlights the ways that chemical and electric rocket engineers measure the efficacy of their solutions. I think the same parameters would apply to both, but since the chapter doesn't really explain said parameters very well, it's not really clear.

One of the long-term goals of my own technical writing is trying to state explicitly the meaning and relationships between different variables and parameters, as well as unifying the equations, notation, and methods to the greatest possible extent.