By David Hambling
Up, up and away! High-altitude balloons called Stratollites might soon be giving the US military and NASA permanent and relatively low-cost eyes in the sky wherever they want.
Developed by US firm World View, Stratollites are uncrewed, hydrogen-filled balloons that tour the stratosphere at heights of between 10 and 46 kilometres. As the stratosphere is layered with winds blowing in different directions, a Stratollite’s path The balloons are controlled remotely from the ground.
World View has used dozens of flights to refine the computer models and algorithms used to navigate the balloons. Along the way, the company claims to have carried out the biggest controlled altitude-change manoeuvre ever by a balloon, switching nearly 8 kilometres in one sweep.
“Multiple times we’ve demonstrated the ability to stay within a very tight radial area – under 50-kilometre radius for over 24 hours,” says Andrew Antonio,