THE AIRSPEED VELOCITY OF AN UNLADEN SWALLOW
Jonathan Corum has undertaken to answer this age-old question. The short answer:
Although a definitive answer would of course require further measurements, published species-wide averages of wing length and body mass, initial Strouhal estimates based on those averages and cross-species comparisons, the Lund wind tunnel study of birds flying at a range of speeds, and revised Strouhal numbers based on that study all lead me to estimate that the average cruising airspeed velocity of an unladen European Swallow is roughly 11 meters per second, or 24 miles an hour.
Read the post for the actual calculations.
(Hat tip: Max Jacobs)
Okay, call me thick, but why didn’t they just use a radar gun on a few birds and take the average? Seems much faster and simpler.
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