Maybe someone can explain to me how an artistic 3D model of an airplane can be an infingement? If you sell it under the name and brand of the product  and/or used copyrighted markings on the model, I can see it (even if I don't really agree with it). However, if you offer a generic jetliner that looks a lot like a certain model, how can that be copyrighted?

I know a lot of 3D modelers use basic blueprints for objects like this, maybe that's part of the problem. But even if I use photo references, I don't understand how that would be infringement. Does this mean that if I sold photographs or paintings of Lockheed aircraft it would be considered an infingement?

I think what is happeneing here is bullying by a big corporation, knowing that 99% of the people they issue these orders to won't have the money to challenge them in court. Look at the case by the University of Alabama against painter Daniel Moore for his football paintings. He has promised to fight not only for himself but for the rights of artists in general. Most people don't have the money or desire to do anything but comply.