Added the Skybolt Engine as a JSBSim user.

README.md

@@ -30,7 +30,7 @@ In 2015, [the NASA performed some verification check cases on 7 flight dynamics
 ## Applications and Usages
 JSBSim is used in a range of projects among which:
 
-* Flight simulation: [FlightGear](http://www.flightgear.org), [OutTerra](https://www.outerra.com/wfeatures.html)
+* Flight simulation: [FlightGear](http://www.flightgear.org), [OutTerra](https://www.outerra.com/wfeatures.html), [Skybolt Engine](https://github.com/Piraxus/Skybolt)
 * SITL (Software In The Loop) Drone Autopilot testing : [ArduPilot](https://ardupilot.org/dev/docs/sitl-with-jsbsim.html), [PX4 Autopilot](https://dev.px4.io/master/en/simulation/jsbsim.html), [Paparazzi](https://wiki.paparazziuav.org/wiki/Simulation)
 * Machine Learning Aircraft control: [gym-jsbsim](https://github.com/galleon/gym-jsbsim)
 * [DARPA Virtual Air Combat Competition](https://www.darpa.mil/news-events/2019-10-21) where one of the AI went undefeated in five rounds of mock air combat against an Air Force fighter (see the [video on YouTube](https://www.youtube.com/watch?v=IOJhgC1ksNU)).