Lawrence Hargrave was a truly remarkable man. When he modestly linked four of his cellular box kites together and added a sling seat, he not only propelled himself 16 feet off the ground in front of a sceptical public, but wrote himself into the history books forever. For on that day, the 12th of November 1894 near Sydney, in a wind speed of 21 mph, Hargrave became Australia’s founding father of modern flight and opened the doors to countless other inventors and pioneers.
Hargrave emigrated to Australia from England in 1865. In 1867 he began an engineering apprenticeship in Sydney and between the years of 1872 and 1883 Hargrave practiced as an engineer, explorer, and astronomer.
Yet from an early age, Hargrave had been interested in experiments of all kinds, particularly those with aircraft. When his father died in 1885 and Hargrave came into his inheritance, he resigned as an astronomer to dedicate his life to full-time research.
Hargrave chose to live and experiment with his flying machines in Stanwell Park, a place which offers excellent wind and soaring conditions and nowadays is the most famous hang gliding and paragliding venue in Australia.
In 1892, during the course of his experiments, Hargrave discovered that a curved wing surface appeared to give greater lift than a flat supporting surface. This ground-breaking discovery is considered to be the founding step in the development of all modern aircraft. Hargrave turned his attention to the behaviour of various types of kites and next discovered that a kite with two separated “cells” or double planes, had the greatest stability and soaring power..
Generously, Hargrave never applied for a patent on his discovery, or any others to follow. Rather he was a passionate believer in scientific communication as a key to furthering progress.
Thus, the Hargrave-designed box kite, with its improved lift-to-drag ratio, was to provide the theoretical wing model that allowed the development of the first generation of European (and American) aircraft.
The weather bureau of the United States was the first to adopt a modification of Hargrave’s invention and the use of box-kites for meteorological observations became widespread. The principle was then applied to gliders and in October 1906 a box-kite aeroplane made the first officially recorded flight. Three years on, the box-kite aeroplane was the usual type in Europe.
Hargrave did not confine himself solely to the problem of constructing a heavier than air machine that would fly. Indeed, he gave much time to the means of propulsion. As a result, in 1889 Hargrave revolutionised engine technology by inventing the radial rotary engine driven by compressed air. However, his development of the rotary engine was frustrated by the weight of materials and quality of machining available at the time and he was unable to get sufficient lift from his engines to build an independent flying machine.
Hargrave never did solve the power-to-weight ratio problem. Yet his 1902 design was put to the test 100 years later when students at the University of Sydney rebuilt his aircraft from the original blueprint, replacing Hargrave’s power plant with a modern one… It flew.
To read more about Lawrence Hargrave and his inventions, see: