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History of Flight: The Beginnings 1970 US Navy Training Film KN-10759a; Paul Garber
🕑 Added 2020-01-29 21:31:17 +0000 UTCmore at http://quickfound.net/
HISTORY OF FLIGHT, THE - BEGINNINGS, THE
EARLY FAMILY LIFE AND THE FIRST BUSINESS VENTURES OF THE WRIGHT BROTHERS. THE FIRST ATTEMPTS TO FLY WITH GLIDERS AND THE FIRST FLIGHT OF A HEAVIER-THAN-AIR POWER-DRIVEN MACHINE.
Presented by Paul E. Garber (August 31, 1899 - September 23, 1992), the first head of the National Air Museum of the Smithsonian Institution.
Originally a public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).
https://en.wikipedia.org/wiki/Flying_and_gliding_animals
Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/
A number of animals have evolved aerial locomotion, either by powered flight or by gliding. Flying and gliding animals (volant animals) have evolved separately many times, without any single ancestor. Flight has evolved at least four times, in the insects, pterosaurs, birds, and bats. Gliding has evolved on many more occasions. Usually the development is to aid canopy animals in getting from tree to tree, although there are other possibilities. Gliding, in particular, has evolved among rainforest animals, especially in the rainforests in Asia (most especially Borneo) where the trees are tall and widely spaced. Several species of aquatic animals, and a few amphibians and reptiles have also evolved to acquire this gliding flight ability, typically as a means of evading predators...
Types
Animal aerial locomotion can be divided into two categories—powered and unpowered. In unpowered modes of locomotion, the animal uses aerodynamics forces exerted on the body due to wind or falling through the air. In powered flight, the animal uses muscular power to generate aerodynamic forces to climb or to maintain steady, level flight. Those who can find air that is rising faster than they are falling can gain altitude by soaring.
Unpowered
These modes of locomotion typically require an animal start from a raised location, converting that potential energy into kinetic energy and using aerodynamic forces to control trajectory and angle of descent. Energy is continually lost to drag without being replaced, thus these methods of locomotion have limited range and duration.
Falling: decreasing altitude under the force of gravity, using no adaptations to increase drag or provide lift.
Parachuting: falling at an angle greater than 45° from the horizontal with adaptations to increase drag forces. Very small animals may be carried up by the wind. Some gliding animals may use their gliding membranes for drag rather than lift, to safely descend.
Gliding flight: falling at an angle less than 45° from the horizontal with lift from adapted aerofoil membranes. This allows slowly falling directed horizontal movement, with streamlining to decrease drag forces for aerofoil efficiency and often with some maneuverability in air. Gliding animals have a lower aspect ratio (wing length/breadth) than true flyers.
Powered flight
Powered flight has evolved only four times: first in the insects, then in pterosaurs, next in birds, and last in bats. Powered flight uses muscles to generate aerodynamic force, which allows the animal to produce lift and thrust. The animal may ascend without the aid of rising air.
Externally powered
Ballooning and soaring are not powered by muscle, but rather by external aerodynamic sources of energy: the wind and rising thermals, respectively. Both can continue as long as the source of external power is present. Soaring is typically only seen in species capable of powered flight, as it requires extremely large wings.
Ballooning: being carried up into the air from the aerodynamic effect on long strands of silk in the wind. Certain silk-producing arthropods, mostly small or young spiders, secrete a special light-weight gossamer silk for ballooning, sometimes traveling great distances at high altitude.
Soaring: gliding in rising or otherwise moving air that requires specific physiological and morphological adaptations that can sustain the animal aloft without flapping its wings. The rising air is due to thermals, ridge lift or other meteorological features. Under the right conditions, soaring creates a gain of altitude without expending energy. Large wingspans are needed for efficient soaring.
Many species will use multiple of these modes at various times; a hawk will use powered flight to rise, then soar on thermals, then descend via free-fall to catch its prey...
