XPlane2Blender is the official exporter for the X-Plane ecosystem. Its scripts can be used to import or export scenery or cockpits from Blender to X-Plane.
Introduction to XPlane2Blender
This tutorial shows how to setup Blender and the X-Plane .OBJ exporter XPlane2Blender. These are the first steps in the process of creating your own custom objects for X-Plane 11.