I think you might find that for Sketchup, it is fairly easy to get modeling for simple objects. When you want more complexity, it can require more digging into the program and I suppose at some point may be as hard as some of the other 3d modeling software. One thing about it, it is written using a scripting language called Ruby, and can run Ruby code. As a result, there are many Ruby plugins that extent the functionality quite a bit.
You need to use MCX with it, and MCX provides capability for setting FSX material properties, and some attachpoint functions. I haven't looked into animation at all, not sure if this can work or how.
scott s.
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