Loon's longest flight spent 312 days in the stratosphere

Some may remember the Project Loon balloons from years past. It's been a while since we've talked about the project, and recently a Loon balloon set a new flight duration record, spending 312 days in the stratosphere. HBAL703 launch from Puerto Rico in May 2019, where it navigated to Peru and provided test service for three months in the country. The team running the project notes that many of their flight systems become devoted to science at certain points.The science in this case, is the goal of learning the secret of healthy balloons. After its primary mission was over, the flight system was sent south to circumnavigate the globe and eventually ended up over the deep Pacific Ocean, floating on the winds for seven months. Eventually, the Loon ended up in Baja, Mexico, where the recovery team collected the flight system for more analysis in March 2020.

Researchers on the project say that the duration record isn't important simply because it flew for 312 days. The bigger success that it's a visible indicator of efforts to make flight systems last longer. The Loon balloons themselves have been improved over the years with alternative materials, changing how the material is sewn together, and by exploring different designs.

Interestingly, some of the strange designs have resulted in at least one of the prototypes being mistaken for a UFO. The current flight systems look more like a traditional high-altitude platform than a conventional stratospheric balloon. This is in part due to the need for Kaplan to have navigation requirements. The teams typically fly millions of simulated flights before they get started on new flight hardware to see the full range of performance the system will offer.

Over the years, the team has determined the correct process for building, shipping, and handling balloons. That is a critical process as even a millimeter-sized hole in the thousands of square yards of plastic used to construct the balloon could be the difference between a long flight and a short failed one. The team is also perfected the launch process using automated launch systems that shield the balloon from wind and fill it quickly.