http://us.battle.net/wow/en/blog/19820046/
Patch 6.2.2 arrives Tuesday, September 1. Once live, players with the Draenor
Pathfinder achievement will be able to take to the skies of Draenor.
Flying on Draenor
Flying has been enabled on Draenor for characters that have attained the
account-wide achievement, Draenor Pathfinder. To help facilitate testing of
this feature, accounts that have not yet obtained the achievement will be
able to purchase a Manual of Rapid Pathfinding from Flaskataur in their
Garrisons on the PTR.