Comment by firesteelrain 13 hours ago
It was connected to an Orbs 32” PicoBalloon
https://balloons.online/orbs-32-clear/
I used 36 awg wire and fishing line. The lower half of the dipole is also 36 awg wire.
No flight clearances are required
If any aircraft were to hit it, then it would be obliterated. This includes Cessna’s as well
As a bugsmasher pilot, I’d be most worried about 40k ft of fishing line wrapping itself around the spinny bits on the front. What’s the tensile strength on that stuff?
Doubt it’d cause an immediate issue, but doesn’t sound very fun to remove.
3-6 newtons or about 0.7-1.3 pounds-force
Also it’s not 40k ft of wire. Altitude is 40k ft
The wire is about 16 ft for one leg of the dipole. That is the taught part. The other just floats in mid air underneath the payload
The community is very small and doubtful the sky will be filled with them
The balloons follow the jetstream from where they are launched. I have seen them fly over the Artic Circle, for example
These and other high-altitude balloons are almost never tethered nor recovered - they're not a kite, that would be completely impractical.
You're nearing the altitudes at which the tensile strength of even supermaterials like Dyneema fibers are unable to lift the weight of their own tail, much less hold up against the tension of the jet stream. You'd need some kind of reverse rocket equation pyramid, where the topmost thousand meters have to lift the entire line, and are therefore made from line 0.6mm in diameter, and the next thousand meters are made of a slightly thinner, slightly less strong, slightly lighter fiber (because they don't have to lift the top thousand meters of line), and so on for the next 50-100km, depending on how much sag you expect the line to have.
"Oops, the balloon popped, excuse me while I do an ultramarathon across town spooling up my thousand-dollar tether from everyone's backyards...please don't cut it or trip over it or drive over it..."
No, it merely trails a 5 meter length of wire that acts as an antenna. You can receive the signals from hundreds of amateur receivers set up across the globe, often receiving transmissions at very long ranges. When the balloon eventually falls, yes, it's litter, but it's only a couple grams - go to your local park and pick up some trash, you can atone for a lifetime of HAB hobby sins with a single black bag full of alcohol bottles, fast food wrappers, and cigarette buts.
Yes, it is not tethered to the ground. The balloon is at the top, then 36awg wire, then solar panels and raspberry pi, then wire hanging down for lower half of dipole
Both top and lower part of dipoles are soldered to Raspberry Pi
It uses WSPR. Some of them use APRS but it is less common
if you're not familiar, 36AWG wire is thin. very thin. according to [0], it is 0.1270mm. seems to me that it might melt free from friction thin.
[0] https://size-charts.com/topics/house-size-chart/wire-size-ch...
I’m familiar; I thought this was tethered to the ground. But it’s self contained within a few meters at 40k ft - not a problem.
I do suspect if you encountered small gauge fishing line being used as a tether, you’d find at least some of it wrapped tightly around your spinner on the ground. Probably not much friction at play.
14 CFR Part 101, Subpart D – Unmanned Free Balloons excludes PicoBalloons due to their size and form
That would explain the difference in experiences. My balloon was 8' diameter at launch and expanded to ~40' when it burst at ~90k'. Mine needed the radar reflector and blinky lights. They were supposed to blink at a certain rate, but we cheated and had lights blinking faster as that's all we could find for our budget/schedule.
I would love to launch a HAB. I learned how to do PicoBalloons from a local group.
It’s not required at all. These are so small that they are not covered by like FAA type regulations
https://www.zachtek.com/product-page/wspr-tx-pico-transmitte...
Solar cells are polycrystalline. You can buy them on AliExpress (very brittle - takes practice soldering them)
I didn’t use the Traquito Solar truss. Too hard to solder. I used a foam dinner plate and solar tabbing wire
What happens if there are heavy winds?