From: Curtis L. O. <cur...@fl...> - 2006-06-14 13:53:59
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Jon S. Berndt wrote: >> None of these are good for planes that haven't been stuck in a wind >> tunnel and "precomputed" >> It's true that with all the FlightGear dynamics engines, you need to have some idea or reasonable guesses as to how the aircraft flies in order to model it. With X-Plane you don't need to know anything about performance, you just plug in the mass and geometry and airfoil and the airplane flies. But if you've never seen the aircraft fly and don't know anything about it's performance, how do you know if X-Plane is doing it right? What is the truth? How well is X-Plane guessing? I think it boils down to this. If you have no idea how your aircraft will perform, X-Plane's guess is probably just as good as anything else. But if you do know how your aircraft performs, what is the best tool/approach to modeling that performance as closely as possible? If you want to nail specific performance numbers dead on, what is the best tool/approach? It's not my intension to knock X-Plane here because I know that an immense amount of work has gone into the flight dynamics engine to help refine and improve it's ability to guess aircraft performance based on the physical geometry and mass of the aircraft alone. It's an interesting tool, but it's not perfect, and it's certainly not always the best tool for every dynamics modeling task ... depending on what types of data you have available and what your end goals are. Curt. -- Curtis Olson http://www.flightgear.org/~curt HumanFIRST Program http://www.humanfirst.umn.edu/ FlightGear Project http://www.flightgear.org Unique text: 2f585eeea02e2c79d7b1d8c4963bae2d |