Actually, three dimensional.

3D flight is generally described as flying an aircraft beyond the point where the wing is in a "stalled" condition. In other words, the wing is no longer generating lift, and the aircraft is kept in the air by the "lift" created by the prop. And yes, a lot of power is required of the engine. A 3D capable plane will usually have a thrust to weight ratio of at least 2 to 1. (ie, a 10 pound plane would require an engine that generates at least 20 pounds of thrust.)
Dennis-