It's tough, but with the 2.8 releases, they've been working on making it easier to use. When I started, the UI was horrible. If you want to start learning it, now's the time.
I originally picked it up to design planes for X Plane simulator, but I mostly use it for making assets for my videogames now.
I'm sure it could be used for airplane design, but Fusion is better at that kind of thing. I'd only use Blender when accurate scale and measurements aren't crucial.