![]() ![]() There are other possible goals in scaling, but it seems to me that this one comes closest to what most people want. In scaling a model from one size to another, you want a model that looks as if it is flying like the original one. To understand scaling and comparison techniques, you must first get a handle on what you're trying to do. Telemaster to a half-size Lazy Bee? How about comparing a 7:1 aspect ratio, 1 1/2-meter, R/C hand-launch glider to an unlimited with a 12:1 wing? A theory of scaling that works correctly should allow such comparisons. If, for example, you scale a Lazy Bee to double size, what should it weigh? It turns out that the weight can go way up over what the "2D loading" for the standard Bee can handle without losing its delightful flying characteristics. The problem with classic wing loadings is that they are only valid for comparison of models in a very narrow size and design range. ft.) is used in the preceeding paragraph, not "number of ounces per 100 sq. The key, though, is that the models all performed about the same! Hmm what's going on here? By the "3D" formula that Ron used, the loadings came out the same within 3 percent! That's a little more like it, no? version.īy conventional wing-loading measures, his models ranged from a wing loading of 2.88 oz./sq. 020 powered miniature at 3 ounces with 150 sq. Ron's article showed that there was a valid mathematical relationship among all the various sizes of his "Ramrod" design. The basic concept is that when you go from a large model down to a small one, there's a way to determine the correct weight, despite all the changes to structure, power, etc. This was before R/C really got going, so he was talking about scaling free-flight models. Jean published an article called "Wing Loading is Three Dimensional", right here in Model Airplane News. Happily, such a theoretical solution exists and works well. A really powerful theory will let you target the correct weight for a new model based on larger, smaller or different design models. There is a much better way to evaluate the weight of a model and compare it to others. Wing loading, as generally used, is very limited in the range where any given loading is valid. Unfortunately, those debates are trying to resolve conflicts that are due to inadequate theory. I have not seen it anywhere else since then, and that was a long time ago. of wing area" was new to me when I read this article for the first time. 24, 2021 The term "number of ounces per 100 sq. Debates over an ounce per square foot here or there can become pretty heavy. Specified for this type of model and that type of flying. of wing area, right? Various wing loadings have been It's common knowledge that it's important to have your model weigh a certain number of ounces per 100 sq. Thanks to Jim Yuzwalk for cleaning up this article a bit to make it easy to read, especially the tables. ![]() ![]() Some of Larry's actual words were bolded and underlined, by Ken, to draw attention to specific statements. 3D Wing Loadings Annotations and Comments were added, in blue font, by Ken Myers, in December of 2021. ![]()
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