The IOCCC Flight Simulator was the winning entry in the 1998 International Obfuscated C Code Contest and is public domain. It’s a flight simulator in under 2 kilobytes of code, offering relatively accurate dynamics, wireframe scenery, and a small instrument panel. Use the keyboard to fly the Piper Cherokee. Loadable scenery files with options to control flight via various keys are available. Be cautious of compile-time parameters needed to build the program. The unique, challenging aspect of fitting a flight simulator into limited code size makes this a noteworthy piece of software. A source distribution can be found to download.
https://blog.aerojockey.com/iocccsim/