Flies without power (6)
I believe the answer is:
glides
'flies without power' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for glides that I've seen before include "Moves along smoothly as on skates" , "Sails or floats on high" , "Flies without an engine" , "Flies without power" , "Moves smoothly over surface" .)