You can fly like a bird at a Move equal to your Action Value. You are not a very agile flyer, basically moving in a straight line between two points each move. You must move at least half your Move each action, or stall. You can swoop. You can take double moves (with a turn inbetween) or a move and an action as usual.
Calculating movement in three dimensions is somewhat different from normal. Downward movement if free. Movement upwards counts normal, but lateral and vertical movement is calculated separately and added together to figure effective distance. So if you move to a point five meters away and three meters up, you have effectively moved eight meters.
See also Hover.
You can purchase this schtick several times; each pick beyond the first increases your Flight and Hover Move by +3.