Don't be too surprised that high-altitude balloons would look alike. It's like airliners. In technology, it's called "convergent evolution." Systems begin to look alike because the solutions to problems are often the same, no matter who is working the problem.
The so called "spy balloon" is tagged Aerostar?
Edit: Ah I see it's another balloon. Raven Aerostar. This is getting weird though.
Don't be too surprised that high-altitude balloons would look alike. It's like airliners. In technology, it's called "convergent evolution." Systems begin to look alike because the solutions to problems are often the same, no matter who is working the problem.