Didn’t the Japanese try something like this during WW2?
Maybe it’s another load of virus.
Yes........
Yes. They used balloons with a system that sensed when the balloon was gaining or losing altitude and would open a valve or drop a sand bag as needed to maintain the altitude range. Once the last sand bag was dropped, the next items would be an incendiary device and/or a bomb.
They were trying to take out our forest reserves in the Pacific Northwest and shift our personnel from the war effort by starting forest fires. A couple of them actually worked and made it here. One wound up killing a pastor's wife and five young teens on a church picnic in Oregon.
https://en.wikipedia.org/wiki/Fu-Go_balloon_bomb
Quite a sophisticated endeavor for the time.