Throughout history, mankind has sought to conquer the sky, but the level of technology and knowledge necessary for this appeared comparatively recently. A special page in the history of aviation are undoubtedly airships, which at first quickly gained immense popularity, then just as dramatically lost it, but today seems to gradually experience its second birth.
Airships are an example of the category of transport “lighter than air”. And in fact it is one of only two types of floating aircraft of this type – in addition to the airship itself, this group also includes balloons. By the way, it is the spherical balloon that is considered to be the official precursor of airships. Such a flying machine was successfully launched for the first time by the Montgolfier brothers back in 1783.
But today these two machines have a key difference regarding its controllability: while a balloon is a non-motorized craft capable of rising above the ground but having no opportunity to adjust its course horizontally, an airship is a controlled ship that can rise and simultaneously maneuver in any direction, including against the wind, and passengers are located in a gondola suspended under the balloon.
Structurally, airships are divided into three types. The first is the rigid models, which have an internal metal frame to maintain the shape of the shell. The second type is the semi-rigid models which have a partial skeleton running the length of the airframe: in this way, the skeleton itself supports the shape of the airframe and the airframe itself is the basis for the construction. The third type is the soft airship where the shape of the airframe is supported by the internal pressure of the lifting gas, most often helium (sometimes hydrogen).
The principle of operation of the airship is based on the fact that in the inner part of the bubble there are one or more air cells (balloons), which are called balloons. They are filled with air (while the rest of the bubble, as previously mentioned, is filled with helium) and then attached to the sides or bottom of the airship. The balloons have the ability to expand and contract to compensate for changes in helium volume as the temperature or altitude of the flight changes. In fact, the pilot directly controls the cylinders with special air valves.
Another structural detail of the airship worth mentioning that is definitely of interest is the nose cone. It performs two tasks at once: providing a point of support attachment when mooring and adding stiffness to the nose, which faces the maximum dynamic pressure loads during flight during operation. On the ground, the inflatable airship is attached to a fixed pole called a mooring mast. By the way, the airship fixed in this way moves freely around the mast in case of changes in the wind direction.
Airship, as the first aircraft with propulsion and steering systems, appeared through the efforts of the French engineer Henri Giffar, who in 1852, attaching a small steam engine to a huge propeller, flew through the air seventeen miles with a maximum speed of about 9 km / hr. However, only after the invention of the gasoline engine in 1896 to build a more familiar prototype airship. The pioneer in this business in 1898 was the Brazilian Alberto Santos-Dumont, who experimented in Paris.
On the other side of the planet, in the summer of 1908, the American army conducted the first tests of the airship Baldwin, named after Thomas Baldwin, who was appointed by the United States government to lead the construction of all airships. He himself had previously invented a 53-foot blimp called the California Arrow, which he used to win a one-mile race at the October 1904 World’s Fair in St. Louis.
Still, the most famous variations of airships in those days were undoubtedly the zeppelins, which featured an internal airframe. They were invented by Count Ferdinand von Zeppelin in 1900, while remaining a career German military officer. His rigid frame airship, which became known by its surname – Zeppelin – flew for the first time on July 2, 1900 near Lake Constance in Germany. It was covered with a cloth that was stretched over an aluminum structure, and lifted into the sky using seventeen hydrogen cells and two 15-horsepower Daimler internal combustion engines.
Eight years later, Ferdinand Zeppelin founded the Friedrichshafen Foundation (The Zeppelin Foundation), dedicated to the development of aeronautics and airship production. A little later, Germany successfully used Zeppelins in military reconnaissance missions, and the British Royal Navy picked up the idea, creating its own airships. That, and also based on the desire not to copy the design of the German rigid airship, soft modifications of these aircraft appeared, which were used to successfully detect German submarines and were classified as “British Class B” airships.
The years between the world wars saw a real boom in the history of airships. Great Britain, Germany, and the United States were mostly involved in the development of large, rigid passenger airships. It is true that the USA distinguished itself by using helium rather than hydrogen to lift its airships because, unlike the latter, it was not as flammable, although it was not cheap. But there were few helium deposits around the world, and the United States banned exports to other countries, so Germany and Great Britain continued to use the more volatile hydrogen gas. As a result, several passenger airships that used hydrogen instead of helium crashed.
However, the real point in the popularity of airships was set by one particular tragedy that happened on May 3, 1937 with the airship “Hindenburg”. Built over 5 years in the Third Reich giant, which was then considered the largest on the planet – according to Novate.ru, it reached nearly 250 meters in length and no less than 40 meters in diameter – that day tried to moor in Lakehurst, but suddenly broke out, quickly fell to Earth, and in a few moments burnt out completely. Not only that, but the tragedy, the victims of which were 36 people, was filmed. The system of passenger transportation after this disaster the airships were quickly abandoned because there was no demand for them. As a result, none of the earlier rigid airships survived the years of the Second World War.
After the tragedy, by the way, the airships were not forgotten at all, but focused only on the soft versions and used as a scientific or military transport. They were also used as early warning radar stations, and there is still a place for them in scientific monitoring and experiments today. However, time and scientific and technological progress does not stand still, so the idea of using airships in civil aviation as a transport is gradually returning – after all, the safety indicators today will in any case be higher. And although the airship still requires a large team, including on the ground, and pilots undergo additional special training, this large-scale type of aircraft will not go completely into oblivion anytime soon.