Games like digital combat simulator

Digital Combat Simulator World (DCS World) is a free-to-play combat flight simulator primarily developed by Eagle Dynamics, and the civilian version of The Battle Simulator. It includes a free simulation of the Sukhoi Su-25T Frogfoot attack aircraft and TF-51D Mustang, an unarmed training variant of the P-51D Mustang. DCS World is expandable through add-on modules as well as user-made add-ons and mods.

DCS World acts as a unified platform supporting "modules" (made by either Eagle Dynamics or a third party) so as to avoid large numbers of individual game releases. This allows for users to join multiplayer servers without needing to purchase every vehicle available, or to more quickly switch aircraft, and allows all development to be done on a single platform. The modularity of the game also attracts talented third-party developers to develop for the platform, furthering its content and popularity.