In order for Project Loon to be successful in bringing Internet connectivity to places where it is normally unavailable, the balloons that carry the equipment to make that possible need to survive up in the air for weeks, months even. That itself is already a challenge, but trying to craft a balloon down here on earth that will survive way up there is almost next to impossible. That is, without trying to pluck a piece of heaven in order to test the extreme conditions that balloons will experience in Earth’s stratosphere.
Testing a balloon that will traverse the stratosphere for months is certainly a curious puzzle. Balloons are produced down here on earth, usually at room temperature, but they are exposed to extreme temperatures as low as 60 degrees Celsius. On the other hand, one can test a patch of the balloon’s material and subject it to such stress tests. But a single piece will behave differently compared to the whole shebang. It would seem that the best test of a whole balloon would be to actually set it flying to the stratosphere, but that is expensive, impractical, and slow. Good thing then, that Google has found a way to do the reserve and actually bring a portion of the stratosphere down to earth to test an inflated balloon under such harsh conditions.
Of course, Google isn’t literally taking a piece of the stratosphere, as if that were possible. Instead, they have enlisted the help of McKinley Climatic Laboratories in Florida, who specializes in doing just that. It has a ginormous hangar that can reproduce extreme cold temperature right here on the ground. The lab has employed by the US Air Force to test its own planes under those conditions and now Google is doing the same for more peaceful and humanitarian purposes.
Google is interested in two things. The first is how the shifting of temperature, between the sun heating up and expanding the balloon by day and the cold of night, would affect the balloon. The second is just how much inflation balloons can take before bursting and where the bursting first occurs. Data harvested from these tests have helped Google refine not just its materials but also its manufacturing process. Now a balloon can be made with just two people manning the process, a huge efficiency boost over their previous system.
In the end, all of these are being done in order to increase the survivability of the balloons in the sky, so that they can bring a bit of Internet heaven back down to earth.
SOURCE: +Project Loon