I've, of course, tried to lower the resolution and reduce all the visual details. At high resolution there are no background at all, the plane sits in the middle of the white empty space. At 640x480, I was getting like 2 Frame Per Second... At the same time, the non-photorealistic flying field was working well at high resolutions.
My understanding is that ATI Mobility FireGL 7800, which my IBM Thinkpad A31p has, is not optimized for working with large textures. Work with textures is a strong point of the "gaming" video cards/chips, while FireGL cards are "CAD" solutions, with limited texture capabilities.