UNITED24 - Make a charitable donation in support of Ukraine!

Military


French Airships / Dirigeable - Early Developments

The balloon was first used in war, and by the French, at the battle of Fleurus, June 26, 1794. This balloon, a captive one named the Entreprenant, was mounted by Charles Coutelle, and was of material benefit to the French General Jourdan by informing him as to the movements of the enemy. This same balloon was later used in the defense of Maubeuge, and in the sieges of Charleroi and Mayence, 1796.

Since the development of the dirigible and the invention of the aeroplane spherical ballooning, whether free or captive, has diminished in interest and value. This is, however, not to say that it has become obsolete. For example, the French army in 1914 made use of auxiliary balloons (320 cubic meters) for colonial expeditions; of the so-called normal balloons (560 cubic meters), captive, for field service; of siege balloons (750 cubic meters) equipped with a ballonet; and of ballons de place (fortress balloons) 980 and 1600 cubic meters respectively, for free ascensions.

The development of the dirigible balloon dates from the year 1852, when Eugene Giffard appeared on the scene. In 1851 he succeeded in making a small steam engine of 5 h.p., which only weighed 100 lbs., and thought it might be useful in connection with balloon work. With the help of two of his friends, he built an airship, which was somewhat of the shape of a cigar with pointed ends. It was 144 ft. long, 40 ft. in diameter at the thickest part, and its capacity was 88,000 cubic feet. The envelope was covered with a net, and a heavy pole, 66 ft. long, was carried below, being suspended in a horizontal position by means of ropes which connected it to the net. Giffard himself saw this, but calculated that he would be able to attain a speed of 6 or 8 ft. a second. On one occasion this result was actually produced.

In 1855 Giffard produced a second balloon, which he had made narrower and longer with a view of diminishing the air-resistance. It was 33 ft. in diameter at the middle, and 230 ft. long, having a capacity of 113,000 cubic feet. Giffard planned a third balloon, which was to be 1,970 ft. long, and 98 ft. in diameter at the middle. Its capacity was to be 7,800,000 cubic feet; the motor was to weigh 30 tons, and the speed to be 66 ft. per second. The immense cost of this scheme prevented it from being carried into execution. In 1868 he made a captive balloon for the exhibition in London ; its capacity was 424,000 cubic feet, and its cost nearly 30,000. A similar one was made in Paris in 1878, having a capacity of 883,000 cubic feet. In addition to all this, a dirigible balloon was designed, holding 1,750,000 cubic feet, which was to be fitted with two boilers, and to cost 40,000. This scheme was thoroughly worked out in every detail, but was never carried into execution. Giffard subsequently became blind, and died in 1882.

Nothing further was done till the siege of Paris. The French Government then commissioned Dupuy de Lome to build a dirigible balloon, which, however, was only tested after the war in 1872. It is curious to find that this man, who was a marine engineer and therefore professionally acquainted with problems of this kind, proposed to employ a crew of eight men in driving the propeller. His method of construction was ingenious, and he succeeded in reaching a speed of 9 ft. a second, which was about the same as Giffard had done. His balloon had a cigar-shaped body; its length was 118 ft., its greatest diameter was 49 ft., and its capacity 122,000 cubic feet.

During the Franco-Prussian war, Gaston Tissandier made many unsuccessful attempts to enter Paris by means of a balloon while it was in a state of siege. A model was shown during the Exhibition of 1881, and they were encouraged to proceed on a larger scale. The body was shaped, after Giffard's model, somewhat like a cigar. It was 92 ft. long, 30 ft. in diameter at the middle, and had a capacity of 37,500 cubic feet. It was made of varnished cambric. The car was in the form of a cage, constructed of bamboo rods, and contained a Siemens dynamo, together with 24 bichromate cells, each weighing 17 lbs. At full speed the dynamo made 180 revolutions per minute and the pull was 26 lbs. When the tests were undertaken it was found that a speed of 9 or 10 ft. per second was attained. It cost 2,000, but there was nothing remarkable about the construction.

So little success had attended the construction of dirigible balloons that it was gradually being regarded as likely to be impossible. Great astonishment was therefore caused in 1884 by the announcement that two French officers, named Renard and Krebs, had described a figure of 8 in a balloon, and had returned to the point from which they had started.

The modern dirigible balloon owes its origin to the efforts of two French officers, Renard and Krebs, of the Engineer Corps. Charles Renard had been studying the problem since 1878 with the assistance of one of his friends, named La Haye, and had hoped with the help of Colonel Laussedat, who commanded the Engineers, to obtain the necessary funds from the Minister of War. It was then pointed out that large sums of money had been wasted on similar projects in 1870, and their request was consequently refused. They therefore had recourse to Gambetta, who was much interested, and promised a sum of 8,000. In the meantime, La Haye had been succeeded by Captain Krebs, and with the help of the latter Renard proceeded with the work.

In 1884 and 1885 they constructed an airship, La France, of the shape of a torpedo, and was slightly larger in diameter at the front than at the back. It was 165 ft. long, and rather more than 27 ft. in diameter at the biggest part, and had a capacity of 66,000 feet. Driven by a propeller actuated by an electric motor, it attained a speed of 6.5 meters per second, and under favorable conditions of wind and weather this balloon made trips, modest to be sure, but significant of greater progress.

The inventors waited nearly two months in perfectly calm weather, but at last, at 4 o'clock in the afternoon of August 9th, Benard and Krebs mounted the balloon, which they called "La France," and made an ascent. As soon as they had risen above the level of the trees in the neighbourhood of Chalais, they set the propellers in motion. Immediately they noticed that the speed was increasing, and as a further encouraging symptom it was seen that small changes of direction could be effected by means of the rudder. The journey was therefore continued from north to south till they crossed the road from Choisy to Versailles, after which they turned to the west. It had not been intended to sail directly against the wind, which however only amounted to a gentle breeze. But their confidence increased, and at a distance of 2i miles from Chalais they turned round, and the balloon was safely landed, after having covered rather less than 5 miles in 23 minutes.

A second expedition was less successful. The wind was rather stronger, and drove the balloon before it. The arrangements connected with the motor were injured, and a descent had to be made at a distance of 3 miles from the starting point. Out of seven attempts it was possible to bring the balloon back to the starting point on five occasions. It was therefore clearly demonstrated to all unbelievers that the dirigible balloon was now within the range of practical possibilities. In spite of its successes, the French had not adopted this type, partly because its speed was insufficient, and partly because it could only undertake a short journey. Renard made further attempts to construct one on a bigger scale, but they were unsuccessful.

Attention to engineering details and construction, especially in making the envelope gas-tight and using, pure gas, brought additional success to the 1904 and 1905 Le Baudy airships, and the latter, which proved most useful in military aeronautical work, was turned over to the French Army, and similar balloons were ordered by the War Ministry. The success of French dirigible balloons led to the construction of an airship for the Wellman Polar Expedition, in which a dash could be made for the North Pole from Spitsbergen. Unsuccessful attempts were made both in 1906 and 1907.




NEWSLETTER
Join the GlobalSecurity.org mailing list



 
Page last modified: 07-07-2012 19:26:35 ZULU