Aircraft Modifacations

[ElSardine6k5]

I want to add a extra center fuel tank to the Project Open Sky  BBJ,is there a free program to do this and is it very difficult?

[Travis]

All you need is notepad.

Open the aircraft.cfg file located in that aircraft's main folder.

Scroll down until you see [FUEL].

There are several tanks in there.  The following is from the stock FS9 737:

[fuel]
Center1    = 0,   0, 0, 2313, 0                 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)
LeftMain  = -3, -19, 0, 1500, 0                 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)
RightMain = -3,  19, 0, 1500, 0                 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)
fuel_type = 2                                   //Fuel type: 1 = Avgas, 2 = JetA
number_of_tank_selectors = 1                    
electric_pump=0

If you want to add another center tank, add and entry that resembles the ones above, but the first part would be "Center2".  Then take a look at the stuff after the "//" sections.  That will tell you where the tank is located in the aircraft.  The numbers correspond to the listings after the "//".