[AngryData]

But hydrogen is also so easy to produce on demand that you can design your balloon to be at small positive pressure all the time and always leaks outwards into the open air. If oxygen is allowed to leaked in undetected, yeah that's a death trap. The same if hydrogen leaked into semi contained oxygen enclosures. But leaking through the skin of the balloon to open sky even with decent size holes and a bit of positive pressure doesn't ignite particularly well, despite hydrogen's wide range of ignition conditions.

It is not such a fool proof technology that everybody should have one, but to me building and operating a hydrogen balloon isn't dissimilar to running a steam locomotive. It can be dangerous if done badly or incorrectly, but it can also be done safely with pretty well known and understood technologies and methods and practices. And considering the massive efficiency of lighter-than-air transport I find it hard to dismiss its potential even so long after their heyday and previous problems.

[Joker_vD]

> And considering the massive efficiency of lighter-than-air transport

What efficiency? You still need to orient it and propel it in the desired direction, unless you don't mind to simply float around on the wind (in which case, yes, we have weather balloons precisely for that and nothing much else).

[AngryData]

Slow moving free floating objects are super easy to move around. You can push a 100 ton piece of equipment with your hands if it is floating. That is why cargo boats still beat out shipping efficiency of rail. There is almost no practical size or weight limits, your only real potential loss, and potential gain, is the movement of your floating fluid be it wind or water, which in the case of air is fairly predictable these days, on top of moving in different directions at different altitudes.