> zeppelins like the Hindenburg were literally just filled with Hydrogen As I understand it this is inaccurate -- there is an aircraft frame (made of aluminum)

> zeppelins like the Hindenburg were literally just filled with Hydrogen As I understand it this is inaccurate -- there is an aircraft frame (made of aluminum) with canvas stretched around it. Then inside that frame there are gas bladders filled with hydrogen. Short of a very intense electrical discharge that would jump the gap, there is no electrical connectivity between the outer skin/frame and the inner bladders. And the bladders in turn were designed to vent upwards in the event of an emergency to prevent exactly this situation, since hydrogen is not an explosive gas unless it is sufficiently mixed with oxygen, which is hard since it will disperse rapidly in air. One thing often overlooked about the Hindenburg and its reputation as being a dangerous bomb with people hanging below it is that there were a substantial number of survivors -- out of 97 passengers/crew, 62 survived. I think the GP is probably correct that had not development stopped, we would likely have very safe storage for hydrogen at that scale; like the hybrid helium/hydrogen mechanisms originally intended for the Hindenburg class.