I don't know a whole lot about licenses. I simply chose GPLv3 because I think it's the main license for open-source projects, but I don't mind any license. Which license do you suggest?
(Disclaimer: I am not a lawyer)
Licenses do [at least] two things: they protect your rights to your work when you share the source code, and they guarantee the rights they specify to those that modify and redistribute the work in whole or in part.
If you don't have strong opinions about FOSS license philosophy I would encourage you to aim for a very permissive license, like the MIT license.
One of the challenges that licensing your work under GPL3 will bring, is that it probably can't be used with more permissive projects. This would effectively prevent it from ever being included in the Orbiter core, XR vessels, and even NASSP (which is GPL2 for complicated historical reasons). This graph shows a very basic overview of the compatibility (I could combined some MIT licensed code with your code, but not the other way around).
Almost all licenses boil down to: "I hereby grant you these rights, one of which is that you will also grant those rights to others." This almost universally prevents relicensing to a more permissive license, because to do so would be to fail to grant the rights guaranteed by the original license to others.
Personally I would go with the MIT license, but that decision is 100% your choice.