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Comment by gamblor956 | Hacker News Reader

It's not the same thing. Airliners are not filled with explosive gas, they're filled with breathable air. They have these specialized things called "fuel tanks" that are purpose-designed to safely hold combustible fuel.

On the other hand, zeppelins like the Hindenburg were literally just filled with Hydrogen. It was a fundamental part of the design; they hydrogen provided the buoyancy needed for the vessel to float. The vessel and the fuel tank were one and the same. Moreover, there isn't a way to design a hydrogen-based zeppelin that can both use hydrogen for buoyancy and hold it safely; even today containers for gas hydrogen are bulky and heavy. The solution is simply not using hydrogen.

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> 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.

> 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.

Hindenburg wasn't the deadliest airship disaster, it was just the final straw. It's the best known of the crashes because it was highly publicized and the last. The USS Akron crash killing 73 of 76 crewmen. There were no survivors from the 52 people on the Dixmude. 44 of 49 died in the R38 crash. 34 of 43 died in the Roma crash. 48 of 54 died in the R101 crash.

Airliners carry a lot of fuel. The wings are fuel tanks, and there are more in the belly. There's so much fuel they cannot even land after takeoff without dumping it.

> Moreover, there isn't a way to design a hydrogen-based zeppelin that can both use hydrogen for buoyancy and hold it safely; even today containers for gas hydrogen are bulky and heavy.

Of course there is a way. The Hindenburg's dialectric problem could have been solved. It's frankly incredible how good we have gotten at making airliners safe despite being pretty much a flying bomb. See the 9-11 films of what happens when two of them, loaded with jet fuel, hitting a skyscraper. Those fireballs weren't from materials in the buildings.

It depends on the plane but airliners can land with full fuel loads. Juan Browne does a great job explaining this on his YouTube channel: https://www.youtube.com/watch?v=4D2Kj0t4t9s.

The video explains that when they do land overweight, they have to be inspected for damage. They will require a much longer stopping distance, too, and the runway may not be long enough depending on weather conditions.

> There's so much fuel they cannot even land after takeoff without dumping it.

This is a false statement.

and the 911 planes were at best half full when they hit as they already had flown around half of their programmed flight distance.

To be fair, it would be more than half full when at half distance, because airliners carry a significant reserve in case they have to divert.

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