3 ms·
And helium is getting expensive. I worked on an airship project in the early 2000's and it cost $100,000 to fill it. And there is always leakage from diffusion
by dmh2000 7y ago
And helium is getting expensive. I worked on an airship project in the early 2000's and it cost $100,000 to fill it. And there is always leakage from diffusion.