Flightgear is a great free flight simulator that is in current development and will soon have a download section of its own here at Simviation.
If you are not aware of Flightgear please see this page
Although Flightgear has it's own forums this board will be for Simviation users who wish to talk about Flightgear, it's current state, addons available and the future possibilities of what is the only open source flight simulator in existence.
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