Speaker Dr John Ackroyd delivered a fascinating talk on Thursday last to the members about the life and inventions of Sir John Cayley (1773 – 1857).
Born in Scarborough, he inherited the Brompton Hall and Wydale Hall estates on the death of his father when he was aged 19 and engaged in a wide variety of engineering projects. These included, the self righting lifeboat,tension spoke wheels (Used in Bicycles), railway crossing signals, caterpillar tractors, and an early version of the internal combustion engine using gunpowder.!
However, he is mainly remembered for his pioneering studies and experiments with flying machines.Images from his notebooks, indicate that Cayley modeled the principles of a lift generating inclined plane as early as 1792. To measure the drag on objects at different speeds he developed a "whirling arm apparatus" at the Brompton Hall Workshops.
These experiments led him to develop an efficient cambered airfoil and to identify four vector forces that influence an aircraft : thrust,lift,drag, and gravity. He also discovered the importance of the dihedral angle for lateral stability in flight, and deliberately set the centre of gravity of many of his models well below the wings for this reason.
The model glider successfully flown by Cayley in 1804 had the layout of a modern aircraft, with a kite shaped wing towards the front and an adjustable tailplane at the back with horizontal stabiliser and a vertical fin.
A thoroughly interesting talk about developments which took place some time before the Wright Brothers took their first flight.
Click on the Photographs to enlarge