5 Create a configuration

At the bottom of the geometry page, click the 'Add a configuration' button. Set a name for the new configuration and a mass entry for the whole aircraft corresponding to the first mass configuration given in the first chapter, as in the image :

If you need in your own projects, you can add multiple lines of masses corresponding to multiple elements (engine, wings, fuselage, etc...), instead of having a single line for the whole airplane.