YOU SAID:
"Fly by the seats of your pants"
INTO JAPANESE
"あなたのズボンの席で飛ぶ"
BACK INTO ENGLISH
"Fly at your pants' seat"
INTO JAPANESE
"あなたのパンツの座席で飛ぶ"
BACK INTO ENGLISH
"Fly in your pants' seat"
INTO JAPANESE
"あなたのズボンの席に座って"
BACK INTO ENGLISH
"Sit in your pants' seat"
INTO JAPANESE
"あなたのズボンの座席に座って"
BACK INTO ENGLISH
"Sit in your pants' seat"
That didn't even make that much sense in English.