I have a quick off topic report that is kind of related. Over the past few years I have developed a small UAS autopilot system that is largely built on FlightGear principles (property system, xml, the same xml-configurable autopilot system flying in real life, lots of borrowed simgear code, etc.) This is something that flies real small uav's in the real world (which among other things validates FlightGear's approach in many ways.)
This winter I have created a version of the property system written purely in python. I then created a C++ interface to the python-property system. Then I did this crazy thing where I replaced the entire C++ property system (which was the same as FlightGear used) with my new python property system which touched just about every line of code and every code and logic path in my entire autopilot system. The point of this was to move towards more of my own UAS autopilot system being written in native python. (If the code memory foot print is stable, and if the performance is fast enough, then what other reason is there to object?)
So I wanted to report that yesterday I went out and did two complete flights with the new python-based autopilot system. I logged about 49 minutes of total flight time and the new system was rock solid, now with a lot of python under the hood.
My real-life autopilot efforts are an offshoot of flightgear, and now headed in their own direction, but I just thought I'd mention it because it is semi-related, and maybe semi-interesting to a few people. If anyone cares to poke around in my code, it is all open-source and can be found here:
https://github.com/AuraUAS It is still a work in progress and the current state is a stepping stone towards even better things, but every step takes time. My design philosophy for this autopilot is simplicity and readability (as long as I can fit the required functionality into the allowed memory and cpu budget, and right now that is defined as a beaglebone/raspberry pi caliber computer.)
Sorry Edward, I don't mean to hijack your thread ... but maybe this is at least loosely related.