When your balloon needs to lift 15 kg to 5 km, it suddenly becomes significantly expensive. According to the internet™, you need 14 cubic meters of helium, which alone would be like $700. You will also expect to lose half of them to random winds, so you need to launch at least 20.

Also, 15 kg drone is not that much destructive, it only carries 5 kg of payload, while Shahed typically carries 50 kg.

[–] CanadaPlus@lemmy.sdf.org 5 points 1 week ago (1 children)

For this application hydrogen makes more sense.

[–] pelya@lemmy.world 2 points 1 week ago (1 children)

Yeah I thought the same thing, but no. People who actually launch weather balloons swear off hydrogen like a plague, because apparently it explodes while you are filling the balloon.

[–] CanadaPlus@lemmy.sdf.org 4 points 1 week ago* (last edited 1 week ago)

That makes sense, although in wartime it would matter less. You can also generate it fairly portably with ferrosilicon and acid.

It's worth mentioning a football field or whatever of Mylar won't be free. Big balloons retail for hundreds on their own according to a quick search.

[–] RamenJunkie@midwest.social 1 points 1 week ago* (last edited 1 week ago) (1 children)

Your math seems off. A generic search says it costs like $500 to run a hot ait baloon on helium, which would be carrying significantly more weight eith 4-5 humans.

I get its not 1:1, but $700 for 15kg seems high.

[–] CanadaPlus@lemmy.sdf.org 3 points 1 week ago* (last edited 1 week ago)

700/14 gives a price of $50/m^3^ or so, and 14 m^3^ makes sense because air weighs around 1kg/m^3^ at sea level (where the helium is measured for trade). Unfortunately, some fucker named a cryptocurrency "Helium" so it's hard to find, but I did turn up this. Due to the situation in the Middle East it could even be multiple times that right now.