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descent was made by Garnerin in Paris. But the balloon had a major limitation in that its
journey was dictated by the direction of the prevailing winds. Directional control

required both a different form of propulsion (the air screw, or propeller) and a
longitudinal shape.

Many decades elapsed before Henri Gifford in 1852 made the first successful flight in
an elongated airship driven by a steam-powered airscrew. Flights driven by steam and

electric engines followed in 1872 and 1882, respectively. In virtually all of these
innovations Frenchmen were the leading exponents. In 1901 Santos-Dumont made the

first circuit in a semi-rigid airship from St. Cloud to the Eiffel Tower and back, and the
period 1903 – 09 was one of great advance in the operation and perfection of semi-rigid

airships in France. However, by 1910 the rigid airship, pioneered since 1898 in

Germany by Count von Zeppelin, had overtaken the semi-rigid dirigible as the reliable
form of airship. So successful was he that his passenger carrying company transported

nearly 35,000 passengers between 1910 – 14. But airship development was ultimately to

be superseded by the development of the aeroplane.

The heavier-than-air principle

The aeroplane came about through the combination of knowledge accumulated over a
period of about 100 years, the experience of flying in gliders, and the invention of the

internal combustion engine. The scientific foundations of mechanical flight were laid by

th
Sir George Cayley, the “Father of Aeronautics”, during the first half of the 19 century.
He experimented with “flying tops” – a primitive form of air screw comprising spinning

vanes that rose to considerable heights – and with model gliders launched from hilltops.

Through these means he recognised the forces of “lift” that air provides to an inclined
concave plane, as well as “drag” or friction which slows the plane down. Theoretically

he also solved the problem of control through the introduction of vertical (rudder) and

horizontal (dihedral) surfaces capable of universal movement. In 1842, using the
knowledge available, Henson designed, but did not fly, a steam-powered glider which

was patented as the “Aerial Steam Carriage”, many features of which were incorporated