BB,
It's a new WWI combat flight sim that's been under development for three years now, and is a stand alone project built on its own proprietary game engine (out of Moscow, Russia).
Here'a a link to David Calhoun's "WWI Air Combat.com" website, where you can view much of the pre-released media for the project we've seen these past years (then titled Knights of the Sky):
Gallery - WWI Air Combat flight sims
We've been told that after the Leipzig Game Con taking place next week, that we'll be seeing new media updates on the sim too.