I, Dan Bowen of the White Star Project, recently gave a presentation on the frontier of amateur science ballooning, a type of balloon called the 'superpressure'. At this I introduce a tool we're working on to help amateurs solve the problems of these balloons. The event was the United Kingdom High Altitude Society first annual Amateur Balloon Conference on October 15, 2011, in London, England. I was unable to travel there, so I combined Skype live video with a pre-recorded presentation.
Now, background info to get you up to speed on the state of amateur superpressure:
This type of balloon has the potential to stay in the air for extremely long times, much longer than the 3 days flight estimated for the White Star's trans-atlantic 'zero-pressure' balloons.
Superpressure is merely the condition where the gas inside the balloon is pressurized higher than the air pressure outside of the balloon. This can only happen with a balloon that doesn't swell up like rubber nor can it be allowed to burst. Practically, you need a super strong plastic bubble.
Mylar is very strong, so Mylar foil (polyester) balloons from parties have been tried many times. Much math has gone into trying to calculate just the right lift and weight are needed to make the balloons pressurize and achieve level flight. Unlike the success in making and using 'zero-pressure' balloons, amateurs have had little, if any success making and using superpressures. The goal is a level float that lasts day and night, without needing to drop ballast.
Most flights seem to rise and simply burst, or more rarely, achieve float, but sink to the ground at sunset. I've taken the time to begin researching publicly available science research papers from the wonderfully open, various US meteorological journals. What follows in the presentation, is a summary of the things I've found that might explain why it isn't working, and how we can make it work.