How to add custom aircraft in SITL?

Hi,

I was testing out SITL and HIL simulators and wanted to know how I can create my own aircraft for simulation.

AFAIK,
JSBSIM is used to simulate the Vehicle dynamics and the corresponding vehicle parameters are defined in a xml file stored in the tools/autotest/aircraft directory.

Am I proceeding in the right direction?

I don’t know how to use JSBSIM for custom planes, but x-plane has a planemaker tool you can use to make your own custom planes. And their flight characteristics will be simulated with the ardupilot executable. So far I have only been fiddling with the throttle and power characteristics, but it has the tools to do much more.

That sounds great! I was looking for something FOSS to work with, but thanks for the tip!
Have a nice day!