Fuel Flow bug with Jet engines

[MSFS 2024] Bug Reports Aircraft
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1

Version: 1.6.13 SU4 latest, note I been seeing this from the start of SU4.. but I thought it was a problem with legacy fuel system, converted to modern latest.. still happening.

Frequency: Consistently

Severity: High

Context: In flight, engines on.. then off.

Bug description:

The simvariables of ENG Fuel flow for engines are staying with values even when there is no flow going via the lines, note I see this bug with new fuel system or legacy.

image
image1492×917 131 KB

**
Repro steps:**

Use a plane with engine type jet, start the engines, wait few seconds then stop it.. monitor the Simvars as above.

Unless I must be monitoring some different variables, I don’t understand why the fuel flow stays always as running once you shutdown the engines??

Best,
Raul

2 Likes
2

ADDITIONAL INFO

This is preventing proper functionality of minimal psf to have combustion.. once you have started an engine, and you hit compile, the variable of fuel flow remains active always..

So this needs addressing.

Best,

R.

3

Hello @SimbolFSReborn

Your issue comes from how your n1_and_mach_on_thrust_table is configured:

n1_and_mach_on_thrust_table = 
0.000000:0.000000:0.380000:0.640000, 
10.000000:0.005000:0.002500:0.000000, 
19.936560:0.031479:0.049381:0.071351,
...

The expected format is:

image
image531×156 4.31 KB

So your first n1:multipliers line is for N1=10%, which becomes the lower bound.
Turbine ends up always taking fuel and producing thrust.

This is a flaw in the current turbine design, that will eventually be reworked.
In the meantime, adding a second line 0.0:0.0:0.0:0.0 will solve your issue.

Regards,
Sylvain

1 Like
4

Just tried and confirms this fixes it.. thank you so much.

Raul

1 Like
5

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