People differ in their diurnal (time of day) preferences: some are morning-types and others are evening-types. These differences are explored in a unique experiment design in which subjects are randomly assigned to produce paper airplanes at either 8:00 a.m. or 10:00 p.m. Our results show that evening-types, at their optimal time of day (10:00 p.m.), produce planes that fly statistically significantly further than those produced by morning-types at their optimal time of day (8:00 a.m.). Evidence also indicates that planes produced by evening-types fly straighter.
— So says the report “Paper Airplane Producers: Morning Types vs. Evening Types” [AIR 16:1]