How fast do hummingbirds flap their wings?

Hummingbirds are the only birds capable of sustained hovering flight, and they achieve it with the fastest wingbeat rate in the bird world. The large species, such as the giant hummingbird of the Andes, flap at around 10-15 times per second; mid-sized ones, like the ruby-throated hummingbird that migrates across the Gulf of Mexico, beat around 53 times; the smallest species approach 80. During courtship displays, some species speed up even further for fractions of a second. For perspective, a sparrow flaps about 15 times per second and a pigeon taking off about 10; the buzzing sound that gives these birds their English name, hummingbird, is precisely the sound of the wings at that frequency, within the range of human hearing.

Wing speed isn't just a matter of frequency. In most birds, the downstroke generates almost all the lift and the return stroke is passive. A hummingbird's shoulder rotates nearly 180 degrees, with a rigid elbow and wrist joint, so the wing behaves like a blade tracing a horizontal figure eight and generates lift on both strokes: roughly 75% on the forward stroke and 25% on the return. It's a solution very similar to that of insects and to a helicopter's rotor, with the advantage of being able to change the plane of rotation and fly backward, sideways, or even upside down. The cost is an extreme metabolism: in hovering flight the heart exceeds 1,200 beats per minute, and the animal must consume more than half its body weight in nectar every day.

In straight flight, a typical hummingbird moves at 40-50 km/h, faster than its size would suggest. The record belongs to Anna's hummingbird, from the west coast of North America: in its courtship dive, measured with high-speed cameras by researchers at the University of California, Berkeley, it reaches about 27 m/s (97 km/h) and withstands an acceleration close to 9 g while pulling out of the dive, comparable to that of a fighter pilot. Measured in body lengths per second, that figure far exceeds any aircraft: a hummingbird covers about 385 times its body length every second, compared with 30-40 for a fighter jet at Mach 2. For engineers designing flapping-wing microdrones, the hummingbird remains the reference model, and several prototypes explicitly mimic its wing kinematics.