BALLOONS AND AIRSHIPS

Modern aircraft developed from the Wright brothers’ flimsy flying machine of 1903. But men were flying a long time before that, in balloons. Some of the first experiments were made by the French brothers Joseph and Etienne Montgolfier.

In June 1783, they released a huge cloth bag filled with hot air which rose several thousand feet. The first manned ascent took place in a Montgolfier hot-air balloon in October 1783. A month later, the first free flight took place in a balloon which had a brazier suspended under the air bag to keep the air hot.

At about the same time, the French scientist J. A. C. Charles was experimenting with balloons filled with the very light gas hydrogen. And in December 1783 he made a successful first flight.

Hydrogen balloons proved to be much better than hot-air ones, and Charles’ design was a model for later balloons. The passenger car, or gondola, was suspended from a net thrown over the balloon to distribute the weight evenly. There was a hand-operated valve in the balloon to let the gas out when passengers wanted to descend. Bags of stones were taken in the car to be used as ballast. They could be thrown out to make the balloon rise higher.

In 1794, the French used balloons for observation in their war against Austria. From then on, balloons were widely used for this purpose up until the First World War (1914-18). In the Second World War (1939-45) tethered barrage balloons were used against low flying aircraft.

Ballooning was a popular sport right up until the 1930’s, and even today there are many keen balloonists. But the greatest present-day uses of balloons are in weather forecasting and scientific research. Such balloons are called radiosondes, because they radio back information about the atmosphere. Most balloons used today contain helium, which is not inflammable like hydrogen.

The drawback with balloons is that they can only go where the wind blows them. So people began to consider ways of powering them. In 1852, a Frenchman, Henri Giffard, built a cigar-shaped balloon with propellers driven by a steam engine. This was the forerunner of the dirigible (steerable) balloon, or airship.

Many designs followed, and in the 1890’s gasoline engines provided them with a new, lightweight source of power. In 1897, an Austrian, David Schwarz, designed a rigid airship in which the outer, gas-tight skin was supported by a framework. It crashed.

One of the spectators was the German Count Ferdinand Zeppelin, who soon began to build his own rigid airships. In 1900, he launched the first one which was 420 feet long. Soon his airships were in regular use for carrying passengers and mail.

The Americans and the British built airships, too, mostly based on the design of the Zeppelins. The British R-34 made the first Atlantic crossing in 1919. In the 1930’s, a series of disasters showed how dangerous airships were, and airship development ceased.