RealFlight
RealFlight is a radio-controlled airplane and helicopter simulation software series created by Knife Edge Software and published by Great Planes. The software allows for the flying of numerous aircraft with simulated physics so that the user can get an attempted real-life flying experience.
Included in the software are various flying sites (or airports) and aircraft models, almost all of which represent real-life models. The software also includes an airport editor and an aircraft editor to allow for the creation of new flying sites and aircraft. 3D design software necessary to create aircraft is not included with the software.
The software is released in "generations", with each new generation including major updates and new features. The most recent generation is Generation 4.5, which included changes such as water and water physics, an improved user interface, more aircraft, more flying sites, and an improved "InterLink Elite" controller. Real Flight requires the connection of an "Interlink" controller for the software to operate.
Knife Edge Software also develops a line of Add-ons for the simulator, each of which adds new airfields and additional aircraft that were available for earlier versions of the software. These free add-on packs have been ReWorked for G4 and G4.5, and are available as free downloads from Realflight's website. Six Expansion packs of planes and airfields are available in addition to the add-ons for an additional cost. Expansion packs ($$$) and Add-ons (Free) are not the same thing.