Laptop = slow almost every time. The GeForce Go is probably the best chipset you could have... but that's not always that great. Laptop 3D cards usually suck.
Don't worry about your framerate. Worry about smoothness and responsiveness. Press CNTRL-C to turn off ground clutter for starters, that should get you a bit of speed. Also, what resolution are you running, and what color depth? Anything over 30 fps should be plenty. Don't worry about the fps on the ground at a busy field, it gets faster once you are up and flying.