Recovering junkie. Politician. Researcher. A 54-year survey of 26,285 European Swallows captured and released by the Avian Demography Unit of the University of Capetown finds that the average adult European swallow has a wing length of 12.2 cm and a body mass of 20.3 grams. Also, the average flight speed of an Unladen swallow is roughly 11 m/s. According to the Coconut Development Board of India, the average coconut weighs 600 grams. With these figures, one can calculate that, beating its wings 18 times a second, the swallow would start travelling at approximately 11m/s, and accelerate to about 11992 m/s.