Question: What... is the air-speed velocity of an unladen swallow? 

Answer: An actual study of two European Swallows flying in a low-turbulence wind tunnel in Lund, Sweden, shows that swallows flap their wings much slower than my estimate, at only 7–9 beats per second:\n\n    “Compared with other species of similar size, the swallow has quite low wingbeat frequency and relatively long wings.” 7 \n\nThe maximum speed the birds could maintain was 13–14 meters per second, and although the Lund study does not discuss cruising flight in particular, the most efficient flapping (7 beats per second) occurred at an airspeed in the range of 8–11 meters per second, with an amplitude of 90–100° (17–19 cm).
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