Comment by dylan604

Comment by dylan604 13 hours ago

20 replies

> had one fly for over a year at 40k ft

inquiring minds want to know. was this tethered? what kind of clearance did you need and what kind of equipment was necessary for safety purposes?

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

  • rogerrogerr 13 hours ago

    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.

    • firesteelrain 12 hours ago

      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

      • timeinput 12 hours ago

        I think there was confusion about whether it was tethered / what the tensile strength of the tether was. Reads like it wasn't tethered.

        How did you communicate with it? Amateur bands? LoRa?

    • dylan604 11 hours ago

      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...

      • rogerrogerr 10 hours ago

        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.

  • bonyt 10 hours ago

    I think you can file a NOTAM for a weather balloon even if you don't need clearance. Might depend on the size and payload, though, like if it's closer to a party balloon than a real weather balloon, and how high it's going.

    • firesteelrain 9 hours ago

      14 CFR Part 101, Subpart D – Unmanned Free Balloons excludes PicoBalloons due to their size and form

      • dylan604 8 hours ago

        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.

        • firesteelrain 7 hours ago

          I would love to launch a HAB. I learned how to do PicoBalloons from a local group.

  • dylan604 11 hours ago

    No radar reflectors or blinking lights of any sort? The little flights up to 90k' with a parachute return required those for night flights. Maybe most people just ignore that??

    • firesteelrain 11 hours ago

      It’s not required at all. These are so small that they are not covered by like FAA type regulations

  • gtoubassi 7 hours ago

    If you have any details written up on your kit (in partic what solar you used) I'd appreciate a link. I'm looking to do similar