The new B-1900C Express seems to run on the auxiliary fuel tanks by default. Although the fuel panel (F8) has a switch to show quantity in either the aux or main tanks, I have not been able to discover how to make the engines draw fuel from the main tanks instead of the aux tanks. Anyone have the answer to that???

Oooops! In my post above, I meant SHIFT-8 for the fuel panel.

Real-world Beech 200 Pilot here... Hope I can help (the systems in the aircraft are almost identical, with the 1900 being on a larger scale)Its actually not possible to switch fuel tanks in the airplane. The fuel system is automated to ALWAYS burn the AUX tanks down first. I beleive its because of a wing loading issue.You'll see on the fuel panel.. The AUX Transfer Pump Switches. Though I've never played with this... I beleive they are fixed in the sim to the AUTO position, which is normal for day to day flight.The only time its placed in ON is if a "NO TRANSFER" condition results... Meaning fuel is IN the aux tanks and is not going anywhere. In the Kingair we have a little amber NO TRANSFER light that comes on right next to the fuel gauges.The reason its automatic like this is because fuel is sometimes likely to be fed to the aux tanks by the system as an "overflow" protection. The engine takes its fuel from an tank in the cowl called the Nacelle tank (Nac Tanks). Some manufacturers call it a Hopper or Feeder Tank. If this tank ever fills completely for some reason, its excess is fed back to the aux tanks and returned by the transfer system when appropriate.Hope this helps answer your question and if you have any others, please feel free to ask.Brendon

Thanks for the comeback, Brendon. I suspected an auto function when I couldn't find anything switchable. I'll test it by adjusting the fuel in the aux tanks down to less than five gallons, then take off and set up a climb. I should find out real quick if it is "auto."