The Horus Heresy has been a big hit with gamers and so Games Workshop is adding more, bringing Aeronautica Imperalis to the realms of 30k. A new rulebook is coming with upgrades for all the different Legions.
From the article:
Aeronautica Imperialis is the game of aerial combat in which hot-shot pilots fight gravity-defying duels in their fantastic flying machines.
But now we shift gears and return to the Horus Heresy to pull some heavy Gs in the Age of Darkness.
This new rulebook catapults your favourite Loyalist or Traitor Legion into swirling dogfights, bombing runs, and nail-biting air raids. Using the existing ruleset, it layers the Horus Heresy setting over Aeronautica Imperialis, making it the perfect complement to your games of Warhammer: Horus Heresy.