YOU SAID:

flying by the seat of your pants

INTO JAPANESE

ズボンの座席で飛ぶ

BACK INTO ENGLISH

Fly in the pants seat

INTO JAPANESE

ズボン席で飛びます

BACK INTO ENGLISH

I will fly at the pants seat

INTO JAPANESE

ズボン席で飛びます

BACK INTO ENGLISH

I will fly at the pants seat