FRC's
I can remember (just) back in the old days as a pimply faced APO taxying out and laboriously going through the TAFFIOHH (T Trim F Fuel etc) checks at the speed of the average glacier, when at the end my instructor said don't forget GFI. I pondered then admitted defeat and asked ," What's GFI?"
"Get F****n' Airborne!" was the exasperated reply.