>>1479328They would need to have adapt to night or cloudy days too. Like only releasing hydrogen if the pressure gets too high (so the density lowers and the lift increases).
It was common to release it because the rest of the airship gets lighter as you spend fuel and it's a way to compensate.
You need a blowout valve for safety anyway (and many other accessories like a ballistic parachute).
The passenger cabin could be even lighter by using fabric like this plane did.
