Manfred von Richtofen challenges Nungesser to a duel. Nungesser shows up for the duel in a two-seater. Two-seaters were known as meat on the table for the one-seat pursuit aircraft that all WW I fighter pilots flew. Nungesser wouldn't have lasted 5 minutes over the Western Front had he actually been stupid enough to fly a two-seater to dogfight against German one-seaters.
February 13, 1917 is depicted as falling on a Friday when it historically fell on a Tuesday.