Simviation Forums

I recently discovered what I think is a strange problem with how the default B737-800 burns fuel.
This airplane wants to burn fuel from the wing tanks faster than it burns it from the center tank and even with the fuel pump and transfer valve on it does not alter it.
Now I am 90% sure this should not happen. I have a couple other B737's that do not do this.
It should burn from the center tank first then burn form the wing tanks.
Question is how or can you fix this problem.

Thanks in advance

My q would be why are you using the default 737 when the TDS versions are so much better with several FD updates?

cevans wrote:My q would be why are you using the default 737 when the TDS versions are so much better with several FD updates?

I have several versions of the B737 including the TDS versions as well as a PMDG B737_800/900 payware
I just thought that this was strange I have since made some changes and the default B737 behaves a little better than it did.

I personally use a mix of default and payware FSX aircraft. Sometimes the default planes are nice if I just want to get in and go somewhere quickly with minimal preflighting.

Yeah, I don't see anything to easily change the fuel flow. What modifications did you make to improve the fuel behavior? I am just curious. Thank you!

TextRich wrote:I personally use a mix of default and payware FSX aircraft. Sometimes the default planes are nice if I just want to get in and go somewhere quickly with minimal preflighting.

Yeah, I don't see anything to easily change the fuel flow. What modifications did you make to improve the fuel behavior? I am just curious. Thank you!

No problem
This is what I wound up doing
I compared the aircraft.cfg file from the default B737-800 to a payware PMDG B737-800 NGX. I changed things like the fuel scaler as it was to high I also changed the engines inlet area and the amount of thrust they produce.
while it is not 100% perfect it is definitely better than what it was and fly's a lot better
Below is some of the entries I used from the PMDG B 737-800

[GeneralEngineData]
engine_type = 1
Engine.0 = -5.943, -16.470, -2.880 // This is the location of the engine DO NOT CHANGE
Engine.1 = -5.943, 16.470, -2.880 // This is the location of the engine DO NOT CHANGE
fuel_flow_scalar=1.2105
min_throttle_limit = -0.3719
max_contrail_temperature = -30

[TurbineEngineData]
fuel_flow_gain=0.002
inlet_area=22.619
rated_N2_rpm=13200.000
static_thrust=24200.000 // Thrust by EEC [26300 TO SLS here]
afterburner_available=0
reverser_available=1
AfterBurnThrustSpecificFuelConsumption = 0

If you compare this to the default B737-800 you will notice some differences.

Before you do anything make a copy of your aircraft.cfg and rename it to aircraft.bak
this way you will have the original just in case.

In case you are not aware of this there is no program that can open a file with a .BAK extension. Just rename it back to cfg

Great stuff Gary. Thank you!

-Richard