The word “fly” can have a lot of meanings. Besides just being what birds and bugs can do, it can also mean “to go very fast,” or “to pass quickly.” The expression “on the fly” means something like this.
If you do something “on the fly,” you do it quickly, and you don't have a lot of time to think about it or come up with a good plan.
This is easy to remember because of how quickly you move when you are flying. But this isn't where “on the fly” comes from.
When pilots fly planes, they have many instruments that show them where and how to fly. If they don't have these things, they have to feel for changes in the wind and the air. One of the easiest ways to feel these changes is through their seats.
This idea led to the phrase, “flying by the seat of your pants,” because you had to feel through your pants to feel changes in the plane. “Flying by the seat of your pants” is acting without careful thought and planning. Eventually, the phrase got shortened to just “on the fly.”
Next time you see a friend doing something without a good plan, tell him or her, don't “fly by the seat of your pants.”
(Kayleen Hartman, Staff Writer)
