Wiktionary
a. (context chiefly US idiomatic English) Done by feel, guess, or trial and error rather than by careful planning, thought or technique.
Usage examples of "seat-of-the-pants".
Jansen strongly recommended we use a man with some seat-of-the-pants background as well as a knowledge of this particular telecontrol system.
The explosion damaged the navigational guidance system and forced Frank Bellwether, its skipper, to try an eyeball insertion, a seat-of-the-pants reentry.
He was the offspring of a proud, daring breed: last of the barnstormers, the stunt fliers and the seat-of-the-pants winged daredevils.
Not only do they know much more about beer than we do, they called upon every bit of the knowledge, skill, expertise, and seat-of-the-pants inspiration at their disposal to make Kingsland Ale a benchmark of the brewer's art.