Airborne: make it fly! Group A
Created on December 29, 2019
GROUP AAirborne: make it fly!
Leonardo Da Vinc'sDreamof Flying
For thousands of years, man dreamt of flying, and one of the biggest dreamers was Leonardo da Vinci. Five hundred years ago he studied and dissected birds, trying to find the secret of flight. He made notes, and initial drawings, but that is as far as he went.Leonardo da Vinci drew sketches of airplanes, gliders, helicopters, and even a parachute.
Helical Air Screw
Mechanical Wing Devices
Flying Machine with Operator
Design of a Glider
What kinds of flying machines did da Vinci come up with?
A page from a 1505 notebook created by Leonardo da Vinci, in which he explored the mechanics of flight.Leonardo intensive study of birds in flight is realised in this articulated wing, an attempt to replicate the structure of a birds wing in mechanical form.
A model of Leonardo's parachute based on a sketch of a parachute from c. 1483 that was found in a notebook margin.
In this flying machine wings are arranged in pairs. The pilot is in a vertical position at the center of a complex system for the transmission of the movement. This machine not only uses the force of arms and legs but also that given by the head. The stairs are retractable and equipped with dampers. Flying machine. ca. 1487 from Manuscript B in the Institut de France.
Da Vinci's glider. Image from the British Library.Leonardo observed the flight of large birds and came to the conclusion that, in the absence of a mechanism driven by human force, the most technologically viable option for flight was gliding “without flapping wings”.
In 1489 he presented what we may recognise today as a machine designed to perform like a helicopter. Da Vinci’s helicopter measured 2 meters in diameter and was made from reed, linen and wire. It was to be powered by four men standing on a central platform turning cranks to rotate the shaft. With enough rotation, da Vinci believed the invention would lift off the ground. Unfortunately, due to weight constrictions, modern scientists do not believe da Vinci’s invention would have been able to take flight. Da Vinci scrawled next to his sketches of the screw-like machine the following description: "If this instrument made with a screw be well made – that is to say, made of linen of which the pores are stopped up with starch and be turned swiftly, the said screw will make its spiral in the air and it will rise high."
Mechanical Wing Device - ca. 1485The design in this diagram is reminiscent of a bird's wing, drawing a parallel to Leonardo da Vinci's elaborate studies of the flight of birds. He made elaborate observations regarding the balance, control and weight displacement of bats and birds. Leonardo da Vinci also recognised the importance of lightweight material in aeronautical creation. He also hinted at a force later defined by Newton as gravity. In the diagrams, all sketches have a primary focus on the framework of a wing, which replicate the complex bone structure of the wing of a bird or bat.
'Ornithopter' comes from the Greek 'ornithos' (bird) and 'pteron' (wing). It describes a machine that's able to achieve flight by flapping wing-like structures.About 1485 he drew detailed plans for a human-powered ornithopter (a wing-flapping device intended to fly). There is no evidence that he actually attempted to build such a device, although the image he presented was a powerful one. The notion of a human-powered mechanical flight device, patterned after birds or bats, recurred again and again over the next four centuries.Central Framework Of Leonardo's Human-Powered Ornithopter - ca. 1485He realised that humans are too heavy to fly by means of wings attached to their arms. The aviator lies prone on the platform of the machine and operates two large membranous wings by means of cords and levers so that they move through the air.
Leonardo observed flying birds in the hills near Fiesole outside of Florence. His sketches of flying birds are located in several notebooks, where he carefully described their flight patterns.Leonardoexamined and analysed the relationship between the shape and movement of creatures born with the ability to fly, and aerodynamics. He made elaborate observations regarding the balance, control and weight displacement of bats and birds. Leonardo da Vinci also recognised the importance of lightweight material in aeronautical creation. He also hinted at a force later defined by Newton as gravity.
How did Leonardo da Vinci explore flight?
Leonardo da Vinci was the first to document flight manoeuvres now called dynamic soaring.
Leonardo's plan view sketch illustrating downwind dynamic soaring flight from right to left.
Leonardo's plan view sketch illustrating northward across-wind dynamic soaring (from right to left) of a flock of four birds along an undulating flight path.
Codex on the Flight of Birds
Take-off & landing
What is a codex?
Lift and drag
Flight of Birds
Leonardo recorded his forward-looking ideas in thousands of notebook pages, known as codices.He produced one codex entirely on flight in 1505-1506, theCodex on the Flight of Birds. The codex analyses bird flight based on the studies made by Leonardo upon his return to Florence relating to gravity and the science of weights as part of a project for the ‘flying machine’.He was particularly interested in understanding how birds soar without flapping their wings. Leonardo sketched numerous birds, added comments about patterns flight and carefully studied. In addition to his studies on flight, the manuscript contains notes on mechanics and botany, architectural projects and hydraulic studies for the fountain spurts and water games in the gardens at the country villa of Charles d’Amboise.
Leonardo studied bird flight and he was the first to document flight manoeuvres now called dynamic soaring. Birds use these manoeuvres to extract energy from the gradient of wind velocity (wind shear) for sustained flight. In his Manuscript E (ca1513–1515) Leonardo described land birds performing flight manoeuvres that match those of albatrosses and other seabirds when they are engaged in dynamic soaring over the ocean.His description pre-dates by almost 400 years the first generally accepted explanation of the physics of this soaring technique by Lord Rayleigh in 1883. Leonardo's early description of dynamic soaring is one of his major aerodynamic discoveries.
The fundamentals of bird flight are similar to those of aircraft, in which the aerodynamic forces sustaining flight are lift and drag. Lift force is produced by the action of air flow on the wing, which is an airfoil. The airfoil is shaped such that the air provides a net upward force on the wing, while the movement of air is directed downward.
The bird's forelimbs(the wings) are the key to flight. Each wing has a central vane to hit the wind, composed of three limb bones, the humerus, ulma and radius. The hand, or manus, which ancestrally was composed of five digits, is reduced to three digits (digit II, III and IV or I, II, III depending on the scheme followed), which serves as an anchor for the primaries, one of two groups offlight feathers responsible for the wing's airfoil shape..
Take-off is one of the most energetically demanding aspects of flight, as the bird must generate enough airflow across the wing to create lift. Small birds do this with a simple upward jump. That doesn't work for larger birds, which must take a run up to generate sufficient airflow. Large birds take off by facing into the wind, or, if they can, by perching on a branch or cliff so they can just drop off into the air.Landing is also a problem for large birds with high wing loads. This problem is dealt with in some species by aiming for a point below the intended landing area (such as a nest on a cliff) then pulling up beforehand. If timed correctly, the airspeed once the target is reached is virtually nil.
Getting the air to move over and under the wing also requires the wing to be moving. This is calledthrust.
Birds use their strong breast muscles to flap their wings and give them the thrust to move through the air and fly.
The shape of the wing and the ability to move it through the air are the two things needed for bird.
The wing of both birds and planes are shaped so that air passing over the top has to travel a longer distance and so it has to speed up as it goes over the top of the wing.
The flying of birds
Birds' bodies are usually lighter in weight than other animals. This is a necessary adaptation that helps them fly. Gravity is an invisible force that pulls heavier objects down toward Earth more than lighter objects. Therefore, the light weight of birds makes it easier for them to move up into the air since less gravity is working against them.
Many bird bones are also hollow or empty, on the inside, which causes less weight. This makes them very lightweight. Some bird bones have thin braces inside them. This makes them very strong. Most of the bones are pneumatic and filled with air sacs instead of bone marrow.
Adaptation for flight
All birds have a special system of airways throughout their skeletons and a four-chambered heart. These organ systems provide the flight muscles with a steady supply of oxygen-rich blood that prevents their wings from becoming exhausted while the bird is in the air.
Instead of weighty jawbones and teeth, birds evolved a light and serviceable beak made of keratin.
Adaptation for flight
How do things fly?
The first force -lift, pushes up on things that fly: airplanes, birds, helicopters and rockets. The shape of the wings of an airplane and the whirling blades of a helicopter create lift as they move through the air. The second force is weight: the force of two masses being attracted to each other.
What makes an airplane fly?
A plane's engines are designed to move it forward at high speed. That makes air flow rapidly over the wings, which throw the air down toward the ground, generating an upward force called lift that overcomes the plane's weight and holds it in the sky.The wings force the air downward and that pushes the plane upward.
How does the Bernoulli Principle relate to airplane flight?
Bernoulli's principle helps explain that an aircraft can achieve lift because of the shape of its wings. They are shaped so that that air flows faster over the top of the wing and slower underneath. Fast moving air equals low air pressure while slow moving air equals high air pressure.
What are the 4 principles of flight?
The 4 principles of flight are drag, lift, thrust and weight.
Rezistenta la inaintare
It is the study of the properties of moving air and the interaction between the air and solid bodies moving through it.
Is the rate of change of velocity per unit of time.
Is the raise to a higher position or level.
To pull (someone or something) along forcefully, roughly, or with difficulty.
To push suddenly or violently in a specified direction.
A body's relative mass or the quantity of matter contained by it, giving rise to a downward force; the heaviness of a person or thing.
Is a strength or energy as an attribute of physical action or movement.
Members of the group