Brin’s airship was originally intended to use hydrogen as a lifting gas. Hydrogen is much cheaper than helium and provides more than 10% more lift, but

Brin’s airship was originally intended to use hydrogen as a lifting gas. Hydrogen is much cheaper than helium and provides more than 10% more lift, but will forever be linked with the infamous Hindenburg disaster in New Jersey in 1937 that claimed 36 lives. First of all, the true cause of the airship fire is still debatable. According to retired NASA scientist Addison Bain's incendiary paint theory (IPT) proposed in 1996, the Hindenburg would have burned even if it were filled with helium. So by switching to Helium as the lifting gas for airships still may not make it 100% fire-safe even in the example that was given.[1] Second of all, Helium is a RARE natural & non-renewable resource (it cannot be artificially produced, at least not yet), albeit abundant on Earth. Most helium on Earth is a result of radioactive decay, which occurs for a long long time.[2] Hence, I think most Physicists would argue the usage as a lifting gas to commercial airship is a wasteful and eventually non-economical way to consume them due to the sheer amount and no practical recycling measures.[3][4] [1]: https://en.wikipedia.org/wiki/Hindenburg_disaster#Incendiary_paint_hypothesis https://en.wikipedia.org/wiki/Hindenburg_disaster#Incendiary... [2]: https://en.wikipedia.org/wiki/Helium#Natural_abundance https://en.wikipedia.org/wiki/Helium#Natural_abundance [3]: https://qz.com/718830/we-rely-on-helium-for-life-saving-care-and-were-swiftly-running-out/ https://qz.com/718830/we-rely-on-helium-for-life-saving-care... [4]: http://www.zmescience.com/science/chemistry/wasting-helium-recycle-052543/ http://www.zmescience.com/science/chemistry/wasting-helium-r...