õhulaevu

Õhulaevu, often translated as airships or dirigibles, are lighter-than-air aircraft that can be propelled through the air. Unlike balloons, which drift with the wind, õhulaevu are steerable and can maintain a controlled direction. Their lifting force is generated by a gas that is less dense than the surrounding air, traditionally hydrogen or helium, contained within large envelopes.

The development of õhulaevu began in the late 19th century and reached its peak in the early 20th century. Early designs were often rigid, with a metal framework supporting the gasbags, while others were semi-rigid or non-rigid (blimps). These vehicles played a significant role in early aviation, used for reconnaissance, transport, and even as passenger carriers. Famous examples include the German Zeppelin airships, which achieved remarkable feats of long-distance travel.

However, the era of large-scale õhulaevu transport was relatively short-lived. Accidents, such as the Hindenburg disaster in 1937, highlighted the dangers of using flammable hydrogen. The rise of faster and more reliable heavier-than-air aircraft, like airplanes, also contributed to their decline. Despite this, there is ongoing interest in õhulaevu technology for specific applications, such as cargo transport to remote areas, surveillance, and tourism, owing to their efficiency and quiet operation. Modern designs often utilize non-flammable helium and advanced materials.