This was an experiment in the use of Microsoft Excel for rocket simulation. The idea is that you get a high level language (VBA), a user interface, a solver and graphing in one package. If the user has to do more, that person can add a scratch worksheet. No DLL corruption. No browser incompatibilities. On the downside, it has some installation quirks and it runs only on a PC.
So I kinda went way overboard with the optimization. You can find Cd from altitude and time. You can find optimal mass (quickly). You can optimize interstage delays and stage burning times (even though you have little enough say in the matter). You can find launch angles required to have the rocket intersect a point in two-dimensional space.(Each point has up to 3 such angles) You can do ad hoc optimization. You can graph trajectories and thrust curves.
It uses a quadratic model of drag, rather than drag from last or next interval. (Hence 2DQD Two-Dimensional Quadratic Drag). It depreciates mass with expended impulse. It interpolates rasp.eng thrust curves such that impulse content of the intervals is roughly constant.
Not sure how the experiment worked out. I'm new to Excel, and didn't even know that one could create objects in it. Knowledge of Excel is helpful. Memory is helpful. Execution is normally fast, but it slows when interval data are saved. FWIW, it's available freefernothin at NEPRA.com (Thanks, Drake) here
-Larry Curcio