Moving or functioning quickly and energetically.(adjective)
Gnu Collaboartive International Dictionary of English: licensed under The Code Project Open License (CPOL)
Use "fast-flying" in a sentence
"There was nothing to be done save wait for the wind, so that he might know how he lay in relation to the fast-flying and deadly centre that from somewhere was approaching out of the gloom."
"How about you -- any close calls with fast-flying tackle?"
"Here small, fast-flying brass dragons waited to carry them into the mountains."