Lesson 8: A History of Aerodynamics – Part II
In this session, we will continue to learn about some of the great contributors to the field of aerodynamics tracing from Leonardo da Vinci, Issac Newton, George Cayley, and the Wright Brothers, and other great flyers and inventors.
Section 1 – On the Wings of the Prophets
GEORGE CAYLEY
The greatest boost to the science of heavier-than-air flight came with the contributions of Sir George Cayley, the “Father of British Aeronautics” who is also considered to be the father of modern aviation.
As a credit to Sir George Cayley, Theordore von Karman, a leading modern aerodynamicist said in 1954, “The principle as we know it now, that of the rigid airplane, was first announced by Cayley.”
Cayley was born in 1773 of an aristocratic family at Scarborough, Yorkshire, England. He began as the sixth Baronet, following the death of his father in 1797. Following his initial schooling, he studied science with tutors and built his own laboratory in a barn near the manor house at Brompton Hall.
In addition to the field of aviation, Cayley contributed much to several branches of science and engineering. His technical work was also interspersed with activities as a member of Parliament.
His efforts covered nearly all branches of aerodynamics including an amazing variety of theories, designs, and experiments. He also tested airfoils, which we known as sections of airplane wings, with a whirling arm.
Cayley’s ideas touched upon ideas on bird propulsion, aerodynamically stabilized projectiles, a gunpowder engine, studies of airfoil geometry, a hot-air engine, ornithopters, beam construction, streamlined shapes of minimum air drag, kites, control surfaces, and other aspects of aeronautics.
Cayley made the world’s first scientific experiments with gliders, generating interest in an aeronautical society. He remained an inspiring figure in aerial navigation for more than half a century.
Cayley was only nine years old when the French Montgolfier brothers made their first balloon flight and had an early interest in the science of flight.
He experimented with an aerial top when he was twenty-three, and began investigating the properties of air and power necessary for flight. He was also the first to point out that it would be impossible to fly unless by way of a sufficiently light engine. Although it did not exist at the time, he forecast the internal combustion engine.
In this realm, Cayley was clearly ahead of his time, and in 1810, he stated publicly that he could construct a balloon “that could carry twenty passengers at twenty miles an hour”. He attempted to form a national aeronautical society in 1837, but was unsuccessful.
Cayley’s first writings on mechanical flight were made known in 1810, and his last in 1854. He designed a model glider as early as 1804. But interestingly enough, he devoted most of his efforts toward the construction of a dirigible.
He could be, in fact, considered the real pioneer of the rigid airship. Cayley was the first man to suggest the division of the airship frame into separate compartments, and the need of bracing the structure to maintain its shape. However, most of the early credit for the airship was granted to Count Ferdinand von Zepellin.
In further examining Cayley’s efforts in mechanical flight, it should be noted that he also made careful calculations of the lift and motor power required, the weight of the fabric to be used, and the possible methods of propelling any airship.
Cayley was the first man to study the problems from the scientific and engineering points of view. His notebooks were full of diagrams and calculations of bird flight, notes of experiments in aerodynamics with a whirling arm to find the resistance and lift of a flat plane which were the first known test of that kind.
He studied streamlined forms, made notes on the first attempt to investigate the law of the center of pressure, and many other knotty problems bearing on flight.
Cayley should be credited with the development of the first heavier-than-air flying machine. This design was published in “Mechanics’ Magazine” in April 1843. This machine only required suitable power to produce the necessary lift and forward propulsion which has since been proven by tests made with a model based on Cayley’s original plans.
JOHN STRINGFELLOW
John Stringfellow first produced a model airplane, powered with an engine, that would fly. Stringfellow began as apprentice to the lace trade in Nottingham, England, showing rare mechanical ability in his early years.
Born in 1799, he left his original master in 1830 and opened his own lace factory at Chard in Gloucestershire. Once his project was operational and running, he turned his attention to mechanical flight, joining with W.S. Henson who was interested in power-driven models.
Henson gave up in despair, but by 1848 Stringfellow had produced his large engine-driven model that was the first machine of its kind to fly under engine power. His one-half horsepower steam engine, including water and fuel, weighed a total of 16 ½ lbs.
In a later model, raised to one horsepower, able to sustain a pressure of 500 lbs to the square inch. He perfected his quest for power by designing a one-horsepower steam engine weighing less than 14 pounds.
He died December 13, 1883 after realizing steam as a means of propulsion, nearly twenty years to the day before the Wright brothers made their historic flight at Kitty Hawk.
