The science behind aircraft originates from the study of our feathered friends in the wild. Birds in flight, basically share all the same flying qualities of our very own military and commercial aircraft. From the aerodynamic construction of a bird’s wing, to their fuselage-like bodies, man has made use of our feathered friend’s profile.
The swift, one of our quickest feathered brethren, assumes all the qualities of a swept-wing fighter jet. Maneuverability was its greatest asset, as its precision aerobatics were used primarily to snatch insects out of the sky. The swift’s swept-wing, where the wings are drawn close to the body for speed, inspired the U.S. military’s F-14 TomCat and Concorde supersonic jets. Nature for the most part, remains ahead of the aerospace engineers.
Owls on the other hand are the most silent of our feathered flyers. They are equipped with a noise reducing feather arrangement indicative of their need to surprise prey as they swoop down, and a more efficient use of the ears in flight. The owls leading edge, primary feathers are serrated like a comb to channel air flow across the wing as a flight stabilizer. Trailing edge feathers on the back end of the wing are tattered like the fringe of a scarf. This tattered arrangement of feathers help to break up the sound waves that are generated as air flows over the top of the wing. The rest of the owl’s wings and legs are covered in velvety down feathers. Noise reduction by way of feather arrangement and texture has led researchers to explore the ideas of retractable, brush-like fringes to mimic an owl’s feather design on aircraft landing gear. For 20 million years, the owl has been flying silently. Now is the time for man to take advantage of what the owl has to offer.
Basic Aerodynamic Features: Thrust, Weight, Drag, and Lift
THRUST: The physical force that propels the aircraft from take-off to flight. Anything from jet engines to other propulsion devices are the main source of this applied energy. The pulling of the propeller powered engine is another form of thrush used in aircraft. Thrust is used to overcome weight and drag, the two major opposing forces that cause most resistance to flight.
LIFT: This is the force generated by the movement of air across the surface of the wing. The wing has an air foil design that allows pressure points on the upper and lower surfaces to counteract each other in a way to give lift to the entire structure. On the upper surface of the wing the air moves faster, and the pressure is lower. This in turns creates lift. Try this simple experiment to prove that point. Put a sheet of paper to your mouth, and blow across it. Notice how the paper lifts as you continue to blow across the top. That is the principle of lift. On the lower surface of the wing the air moves slower, and the pressure is higher. Those two pressures insure the lift of the aircraft.
DRAG: As the opposite force of thrust, drag acts to slow the aircraft down. The friction of the aircraft structure is what the thrust of the engines must overcome. To minimize aircraft drag, all rivets, fasteners, and external accessories are as flushed to the aircraft surface, or aerodynamically configured as possible. Ultimately, drag can never be completely eliminated.
WEIGHT: The gravitational pull of the earth, weight, is the opposite of lift. Nothing can be done to counteract gravity. Drag can be reduced; more thrust can be applied; and a better wing may one day be engineered, but in the end, weight and gravity will be king.
So as the these principles of flight are applied, I wish you Happy Flying.