I have a copy of the pilot's manual for the Spitfire. That plane had some strange quirks. For instance, The Merlin engine had a normal carburetor with a float. Pilots were advised not to go inverted for less than 1 G for very long. The engine would stop. Also, if the gear would not come down, you were told to roll inverted and do a split-S to make the gear come down. (what if you were on final approach?)