>>jnord+(OP)
QRPLabs sell even lighter trackers https://www.qrp-labs.com/u4b.html

and AFAIK are the goto supplier for HAB (High Altitude Ballooning) enthusiasts.

>>jnord+(OP)
Very cool! Brings this to mind: https://www.theguardian.com/us-news/2023/feb/17/object-us-mi...

>>bambax+sDa
If you are wanting to send images, there are already some cool ways to do that: either SSTV (https://en.wikipedia.org/wiki/Slow-scan_television) or Wenet, which sends them at a much higher speed: https://github.com/projecthorus/wenet.

>>jnord+(OP)
If you're interested in high altitude ballooning, there's an active community around it.

https://arhab.org/

https://www.superlaunch.org/

>>jnord+(OP)
Tracking site: https://amateur.sondehub.org

>>jnord+(OP)
I wish the regulations around HAB were not so lighter-than-air gas centric. Hot air balloons are much more accessible, especially solar heated hot air balllons. But they have much less lift per volume and so the FAA FAR 101 rules basically say they all have to be treated as the type where you inform the FAA beforehand and then every hour about their position among other things.

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-F...

>any balloon that is moored to the surface of the earth or an object thereon and that has a diameter of more than 6 feet or a gas capacity of more than 115 cubic feet.

And the regulations on tethered balloons end up being even stricter than letting them go.

>>jnord+(OP)
I wonder what your liability would be in the event your balloon were to be struck by a commercial aircraft and cause injury to the flight crew or passengers?

https://komonews.com/news/local/weather-balloon-launched-in-...

>>NoiseB+HMb
FAA explicitly requires birds used in strike tests NOT be frozen, because frozen birds do not realistically simulate real bird strikes.

https://en.wikipedia.org/wiki/Chicken_gun

>>jnord+(OP)
I’ve been working on a hobby project to send a Raspberry Pi into the stratosphere (nothing really novel) but with all custom software. The entire process, hardware, and stack is documented on the GitHub [1]. Essentially all the software and major components are purchased. I’m just waiting for the spring and then start some tests with balloons, helium mixtures, and iron out any regulatory issues. If this interest you or you have any experience would love help or contributions. The launch will happen in Tennessee.

[1] https://github.com/stratopi-org/stratopi

>>NoiseB+HMb
Well first, the linked article was regarding a weather balloon that impacted the windscreen, not the engine, and it did cause an injury to the flight crew. Here are pictures of the bloody, glass-shard filled flight deck. https://www.facebook.com/aviation247/posts/n17327-united-air... So the hazard is real.

Now back to your uninformed comment. I do certification testing of jet engines, and we most certainly DO NOT test jet engines against the ingestion of airborne electronics.

I have personally loaded and fired the five barrel bird gun at General Electric’s Peebles Test operation many times over the years. We use a range of birds and bird simulators, but none of them are ever chickens, and none of them are frozen.

There is not any requirement for zero engine damage. Little sparrows will do no damage. Ducks and geese cause extensive damage every single time. Extensive engine damage is permitted so long that the engine shuts down without causing catastrophic damage to the airframe. The specific damage that must be prevented, per 14 cfr 33.75, is below. Any other damage is acceptable.

(i) Non-containment of high-energy debris;

(ii) Concentration of toxic products in the engine bleed air intended for the cabin sufficient to incapacitate crew or passengers;

(iii) Significant thrust in the opposite direction to that commanded by the pilot;

(iv) Uncontrolled fire;

(v) Failure of the engine mount system leading to inadvertent engine separation;

(vi) Release of the propeller by the engine, if applicable; and

(vii) Complete inability to shut the engine down.

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-C...

>>nodeso+3Yb
Very cool project!

I saw you were looking for help sourcing things like balloons and gas. https://groups.io/g/GPSL/ worried be a great place to go and ask for help with that, if you haven't already.