TLDR: Airships are big balloons that can fly in the sky. They were used for transportation and military purposes, but their popularity declined after airplanes became more advanced.
Airships, also known as dirigible balloons, are a type of aircraft that can fly through the air using a gas that is lighter than the surrounding air. In the early days, airships used hydrogen gas because it was readily available and had a high lifting capacity. However, hydrogen is highly flammable, so later airships switched to using helium, which is not flammable but is more expensive and less readily available.
Airships come in different types: non-rigid, semi-rigid, and rigid. Non-rigid airships, also known as blimps, rely on internal pressure to maintain their shape. Semi-rigid airships have a supporting structure, such as a fixed keel, to help maintain their shape. Rigid airships have an outer framework that carries the structural loads, while the lifting gas is contained inside. Rigid airships are often called zeppelins, named after the German company that built many of them.
Airships were the first aircraft capable of controlled powered flight and were used for various purposes, including transportation and military operations. However, their popularity declined after the development of airplanes, which were faster and more maneuverable. Additionally, airships were prone to accidents, including high-profile disasters like the Hindenburg disaster in 1937.
Today, airships are still used for certain purposes where their ability to hover for long periods outweighs the need for speed and maneuverability. These include advertising, tourism, camera platforms, geological surveys, and aerial observation.
In summary, airships are large balloons that can fly in the sky. They were used for transportation and military purposes but became less popular with the advancement of airplanes. Airships are still used today for specific applications where their unique capabilities are advantageous.