Single player demo of Biplane for MacOSX. Extract the zip file and execute biplane.app. You may need to tweak your security settings to launch the game.
This release of Biplane is free for everyone. It only has single player features - tutorials and free flight mode. The intent of this release is to provide early access to the game and to allow players to familiarize themselves with the controls and flight dynamics.
Read all about it here: Biplane3d.com
