Lindstrand builds airships, or blimps as they are commonly referred to, for a specific end use. Since the design and manufacture is carried out in house, airships of almost any sizes can be built to the client’s requirements. Airships are always free flying and can use either lifting gas (such as helium or hydrogen) or heating the air like a hot air balloon. Airships are more weather sensitive than aerostats or balloons, but are equally at home in the tropics as in the artic. Since airships are large they create a lot of drag and are only used when speed is not of importance. Airships are excellent surveillance vehicle for the police and the military. They are also widely used for scientific research such as earth mapping, diamond hunting and mine detecting.
The main types of airship are non rigid (blimps), semi-rigid and rigid. Non rigid airships use a pressure level in excess of the surrounding air pressure to retain their shape during flight. Unlike the rigid design, the non-rigid airship’s gas envelope has no compartmentation. At sea level, the ballonets (internal flexible cells) are filled with air. As altitude is increased, the lifting gas expands and air from the ballonets is expelled through air valves to maintain the same hull shape. To return to sea level, the process is reversed. Air is forced back into the ballonets using auxiliary blowers. An airship can be steered and propelled through the air using rudders and propellers or other thrust mechanisms. Airships can be flown either by a pilot, by remote control or via a pre-programmed flight path.
The Flying Carrot
The Lindstrand HS-110 Thermal Airship, ‘the Flying Carrot’, takes flight over Oswestry, United Kingdom, alongside a Lindstrand 120A hot air balloon used as the camera platform. On this day the flying conditions were ideal and visibility was excellent – if you look very closely, you can see the Lindstrand factory in the background!