Airships were the first aircraft capable of controlled powered flight and were thought to be the future of travel for some years in the early 20th century.
- However, fundamental technological shortcomings and the rapid development of aeroplanes killed the idea of airship transport.
- They see limited use today as advertising platforms, for aerial observation by scientists and militaries, and in the tourism industry.
- Airships are lighter-than-air aircraft that are lifted by gas with a density lower than atmospheric gases. This principle also operates in helium balloons.
- Early airships used hydrogen as the lifting gas since it was cheap, easy to produce, and the lightest existing gas. But hydrogen was also extremely flammable.
- Most modern airships use helium, which is non-combustible. However, it is scarce on Earth, and thus very expensive.
- While aeroplanes easily beat airships on speed, airships could in theory be ideal freight vehicles because of their exceptional “lift-to-drag ratio” — which means they expend far less fuel to move the same mass of material.
- Airships are significantly less polluting than aeroplanes as they do not burn fossil fuels to achieve lift.
