April 2nd, 2022: We learned a lot on this flight. First the bad news, we believe KK9H/2 has stopped reporting not having woken up this morning. We believe that our short flight has to do with the balloon, but we don’t believe it burst during the flight. We actually have a theory that the balloon was not adequately sealed at the valve. We knew that we were going to have difficulty once we received our balloon order. This balloon had a short neck and didn’t heat seal as our other balloons. Our Technical team decided to use Kapton tape which is used on the NASA shuttle to plug a hole in space. If it’s good enough for NASA… anyway, that’s what we tried. Below is a slideshow on the process of sealing
There is a lot of practice needed to get the free lift just right. We want the balloon to have a nice steady ascent, but not meet any obstacles along the way. We started off with a package that weighed around 18 grams. When you think about it, 18 grams isn’t a lot of weight, if you’re mailing a first class #10 envelope through the US Mail. One ounce of weight or 28 grams for one stamp. But on a Pico Balloon, one ounce is a lot of weight. If we want to get our desired altitude to fly above the clouds and weather, we need either a lighter package or a bigger balloon or a combination of both. We got the bigger balloon. Now we need to figure out how much additional grams of gas we’ll need for a successful launch. More gas for free lift means less altitude at peak. So we started out with an additional 6 or so grams, I asked Michael to give us a little more. After our last 2 launches that landed in a tree, I was a little nervous and wanted just a little more gas. We went a little higher to just over 7 grams, added the tape to seal and weighed again. Is it possible the tape weighed almost a gram? Below is before and after sealing. it was a beautiful launch, we had some wind, but a nice steady ascent above the trees, Phew what a relief.
We had achieved successful flights with the 36″ Chinese made balloons, one having flown 19 days and the other 10 days making it almost around the globe. The balloon that went for 19 days was a single balloon getting an average altitude of 24,000 feet. We were heading for our “Around the World” tour when our balloon left the Jet Stream and toured the Marshall Islands for about 8 days. For the 10 day balloon flight we used 2-36″ balloons and reached an average altitude of 28,000 feet. We lost that balloon arriving back in North America and losing a signal around Canada. For that flight, we went farther and higher than we’ve ever gone before.
What we were hoping for was to find a balloon that would accept more volume and reach the 40,000 foot level. We were very close, reaching 35,000 feet, 3 hours into the flight. Since the balloon did not wake up the next morning, we were unable to find out if it did reach the higher altitude.
Where we are now:
We have 8 more Yokohama balloons, one more to test, how to make a good seal. Our Technical Team is suggesting to fill the balloon completely, sealing and placing the valve in water to check for bubbles. We’ll be able to weigh for total grams of lift after many days. It also has been recommended to have a flight with a battery on board in addition to solar panels. That way we can continue to get flight data at night. We’re not expecting to have batteries on all our flights, we just need good data at night, sending a signal once every few hours will give us many nights of data.
We also have on order for other Sphere balloons from different sources. We are after all, after the Science of Pico Ballooning. With every launch is a learning experience.
One thought on “13th Flight: the Good, the Bad and the Better”
Improvement and innovation is part of science.
The battery idea for the dark periods sounds like a good idea. Finding a light enough battery may take some effort, but should be possible. Or a little more gas…
After all the tiny balloon is up against the forces of Mother Nature . Not a small task. And along with planning and development, luck is important too in this case.
Always fun tracking the tiny craft across the globe