Hummingbird Flight
Photo from:
https://clackhi.nclack.k12.or.us/physics/projects/rates_around_us/hummingbird%20Folder/Ruby-throated%20Hummingbird.jpg
Background:
The flight mechanisms of hummingbirds allow them to hover almost indefinitely and scientists have wondered for ages about how the bird is able to move so quickly, like an insect, but still has the body structure of a bird. Researchers have believed for decades that hummingbirds used the same flight mechanisms as insects; but studies conducted within the past decade have proven that hummingbirds have their own unique flight characteristics, different from insects or other birds.
Forces Affecting Flight
A hummingbird must compete with the force of gravity, which pushes down on the bird. By flapping its wings, the hummingbird is able to create lift (which pushes the bird upward) and thrust (which helps the bird maintain forward movement). Drag is the force that conflicts with thrust, air resistance or friction slows down thrust.
Flight Mechanisms:
Although the hummingbird's flight mechanisms have been compared to those of insects, the hummingbird has all the capabilities and limitations that birds have. An insect has wings that are almost flat and they gain their lift to fly using two mirror image half strokes, moving their wings back and forth in a figure eight pattern. This allows the insect to produce nearly equal lift on thier up stroke and down stroke. A bird however, produces virtually all of its flying lift on the downstroke. A hummingbird is unique in the fact that it can produce 25% of its weight support during its up stroke and 75% of its weight support during the down stroke.
Photo from:
https://photo.net/photodb/photo?photo_id=1732997
Wing Structure
Photos from:
https://www.learner.org/jnorth/humm/spring2010/Sightings031010.html
Hummingbirds are able to hover for sustained amounts of time because they take advantage of their wings during the up stroke, a feature that is aerodynamically wasted in other birds. Their wings are designed to create lift as well as thrust. They do have some flight characteristics of insects, like flat wings which allow them to move quickly and in all different directions. Hummingbirds are the only species of bird that can fly backwards, and they can also fly forward, up, down, and even upside-down. The motion of their wings also changes angles with each flap, like insects. But hummingbirds also have wings that flex, twist, and arch, like those of other birds. They also are able to expand and contract their tail feathers, which helps them to hover in midair.
Hummingbirds can flap their wings an average of 50 times per second, and 200 times per second during courtship, so to the average human eye their movement seems like a blur.
Photo from:
https://farm2.static.flickr.com/1175/1065041982_8d4eda2fe6.jpg