The friendly skies are about to get a bit more competitive. Microsoft's official Flight Simulator X communit Web site: http://www.fsinsider.com/Community/News-Articles/fsroadmap.htm has been updated with news of the game's first full expansion, Adrenaline, and the add-on introduces multiplayer air racing to the game, as well as a handful of other new features.

Scheduled for takeoff during the holidays, Adrenaline will include new missions and new aircraft as well, specifically the P-51 Mustang. It will also support standard Games for Windows features and include support for DirectX 10.

In the near term, an update for the game is expected to arrive in April with a "targeted set of performances and content enhancements to address the most common customer requests." A DirectX 10 update for the game's visuals will also be made available around the launch of Adrenaline.