My default 747 shows 10* nose up when I am on AP/ALT at any given altitude. When I attempt to trim it out, it goes back to 10* up. Any thoughts?
It's pretty usual that level flight isn't approximately 0º. You must take into concern the weight of the aircraft and also its speed. Cruise faster and the nose will approach the horizontal line. Also, reaching your destination, you will notice that it automatically goes closer to the horizontal line because the fuel is being consumed so weight is decreasing. It's all to do with forces on the aircraft really.
Ive done a lot of BIG airplanes in FS9 that do that. It happens in real life