Hello, Marco
Nothing wrong.
The flight speed is subordinated to the flight altitude.
If you stay even closer to sea level your top speed will be even lower.
But, if you increase the flight altitude, decreasing the density of the atmosphere, you will be able to travel much faster.
You found the Milky Way immediately !!
It is an additional mod, called during the initialization of the Sphere, extremely simple at the programming level (much less simple to be able to size everything so that the overlap with the Outerra sky was acceptable and synchronized ...) and little demanding of resources.
It is not as perfect as I would like because it is not covered by clouds and loses brightness with increasing altitude, contrary to how it should be in reality.
It could be a suggestion for developers who, of course, would be able to implement it internally, directly in the Outerra code and ... better than mine.
I wish you have fun !
![Cheesy :D](http://forum.outerra.com/Smileys/default/cheesy.gif)