Concorde Takeoff （JSBSim-Python）

[ysh11o-2020]

Hello, Im trying to do a takeoff simulation using the Concorde model in Python, but im facing an issue. When I try to make the model takeoff the velocity gets lower and it stopped.
This is my Code ,This is my error GIF, what im doing wrong?

[ysh11o-2020]

:( Finally, i find my error, for Concorde initial state the tank is empty, so run out the fuel.
fdm["propulsion/refuel"] = 1 add this line to my python code, then it work

[ysh11o-2020]

i am a beginner of the jsbsim, if i set the value of "propulsion/refuel" to be true, how long should i turn if off ?, or do nothing is also fine

[ysh11o-2020]

:) Hello, I replaced the 787-8 in the Unreal5 demo project with the Concorde, and then I found that only tanks 13-16 were used during takeoff. I would like to know how to set up the xml file or modify my python script

[ysh11o-2020]

add this line fdm['propulsion/fuel_freeze'] = 1