The developers of the open source FlightGear flight simulator have released version 2.10 with new features and improvements such as atmospheric light scattering, reduced memory requirements, and streamlined joystick configuration.
FlightGear is a highly realistic flight simulator program for use on ordinary PCs. It has been developed on Linux but is also available for most other common platforms. The wide range of aircrafts and terrain, and the realistic simulations of the aircraft behavior and the environment, including the sun, moon and earth make it both fun and instructional. Besides the aircraft you are flying yourself, you can have other planes controlled by the systems AI (Artificial Intelligence).
There are more than 400 aircraft and more than 80 different airlines with their distinct liveries (paintings). AI and multi-player aircraft can produce sounds like the main aircraft. Depending on the selected airport, FlightGear starts at different parking spots to match the size and type of the aircraft, and in some cases there is a visual guide leading you to the active runway along the correct taxiways.
The software includes a highly realistic weather simulation module that simulates the interaction of the atmosphere with the terrain. You can make weather from downloaded or custom made METAR weather reports and experience for example the interesting effects of weather phenomena occurring between different meteorological systems. This includes thermals (localized upward air flow due to high surface temperatures), cloud formation at mountains due rising and cooling air, cold fronts leading to precipitation and fog layers, etc.
To increase realistic appearance, random buildings and trees are placed based on the terrain texture, you can select between summer and winter textures.
For more details on the latest version see the official announcement.