Having not watched the video, obviously hydrogen is a bad idea, but I’d also say no to helium airships until it becomes a replenishable resource through nuclear fusion.
Kerosene in airplanes is actually significantly more dangerous. Airships with hydrogen are the only realistic option and the safety of it is only a minor engineering problem today.
Hydrogen is a nuisance of a gas, though - it has a very wide combustible range of mixtures.
But an airship envelope containing multiple lifting units of hydrogen could be passivated by filling the envelope with a non-combustible gas like helium.
So, there’s a big sausage providing structure and that’s full of helium (or nitrogen, or CO2, or anything else which doesn’t react with hydrogen in normal conditions)… and it contains balloons full of hydrogen. If one of them springs a leak, the leak won’t be going into an environment that supports fire. And if the leak then proceeds into surrounding air, the hydrogen is hopefully diluted beyond its combustible range.
Considerably less expensive than using helium only. But considerably safer than using hydrogen among air.
Technology and materials sciences have come a long way since the 1940s. For example, we can probably skip sealing the gasbag with solid rocket fuel. Hydrogen gets better lift than helium, it’s not a limited resource with higher-priority medical uses, and doesn’t require petroleum-style drilling. It’s flammable, as we saw in the past, but with modern engineering, modern materials, non-conductive pressure vessels, emergency release valves, no ignition sources or sparks in proximity, it seems like it can be done pretty safely.
Until recently, I think, modern aviation had been admirably safety-focussed, in everything from engineering to operation. I’m not a fan of the airline industry and especially Boeing’s recent shortcuts, but I think solarpunk is very much about picking and choosing which parts of our society to keep and which to reexamine to see if they can be done better. Aviation safety is one of those things our society does know how to do well, and that seems very much worth keeping to me. Overall I trust aviation engineers to find ways to do hydrogen airships safely.
Part of the safety focus is from sticking so many people in the same fuselage - which, being big, has no individual rescue equipment and cannot be brought down by parachute either - so nothing critical is allowed to fail.
Side note: that’s not the only possible model, however - one can also design heavier than air craft that are smaller, almost passively safe (falling controllably without power, at somewhat above parachute speed), and design small aircraft that have rescue systems (parachutes which can land the whole aircraft).
Size itself is then a function of economic realities (air travel has undergone explosive growth).
Blimps would have to somehow fit in. Having considerable air resistance, blimps cannot travel as fast. Being unable to travel as fast, they would fall behind at moving X people per hour - while a blimp makes one roundtrip, a jet aircraft would make multiple roundtrips.
If however a jet aircraft is deemed environmentally unsustainable on account of fuel use - then the milestone to compare a blimp against will be a propeller-electric aircraft. Which is more limited in speed, requires charging time, is more limited in range - and therefore makes less roundtrips in an unit of time.
From one viewpoint then, the success of airships thus depends on whether fast aircraft can reduce their environmental footprint. If they can, blimps will not be widespread. If they cannot, blimps might become widespread.
Overall, a fast airplane is effective at getting results (transporting people) but not necessarily efficient at doing that. There is perhaps only one aspect where a high-powered aircraft is more efficient… use of space. But space is not a scarce resource in the atmosphere. Only on the runway.
Out of the previous considerations, I come to the conclusion: blimps probably won’t replace airplanes. Especially for longer trips, having to wait less is what makes people prefer speedier travel. Blimps cannot provide that. However, airships might carve out a niche for servicing shorter routes and local traffic.
Do you have any idea how much fusion you’d have to do to have it be a significant source of helium?
*edit:
I was curious but had to guess ranges to do the maths. To fill a single Flying Whale airship, a 2 GW fusion plant needs to run between 90 and 850 years.
Having not watched the video, obviously hydrogen is a bad idea, but I’d also say no to helium airships until it becomes a replenishable resource through nuclear fusion.
Kerosene in airplanes is actually significantly more dangerous. Airships with hydrogen are the only realistic option and the safety of it is only a minor engineering problem today.
Hydrogen is a nuisance of a gas, though - it has a very wide combustible range of mixtures.
But an airship envelope containing multiple lifting units of hydrogen could be passivated by filling the envelope with a non-combustible gas like helium.
So, there’s a big sausage providing structure and that’s full of helium (or nitrogen, or CO2, or anything else which doesn’t react with hydrogen in normal conditions)… and it contains balloons full of hydrogen. If one of them springs a leak, the leak won’t be going into an environment that supports fire. And if the leak then proceeds into surrounding air, the hydrogen is hopefully diluted beyond its combustible range.
Considerably less expensive than using helium only. But considerably safer than using hydrogen among air.
SK plane crash had all deaths from fire, not impact.
Technology and materials sciences have come a long way since the 1940s. For example, we can probably skip sealing the gasbag with solid rocket fuel. Hydrogen gets better lift than helium, it’s not a limited resource with higher-priority medical uses, and doesn’t require petroleum-style drilling. It’s flammable, as we saw in the past, but with modern engineering, modern materials, non-conductive pressure vessels, emergency release valves, no ignition sources or sparks in proximity, it seems like it can be done pretty safely.
Until recently, I think, modern aviation had been admirably safety-focussed, in everything from engineering to operation. I’m not a fan of the airline industry and especially Boeing’s recent shortcuts, but I think solarpunk is very much about picking and choosing which parts of our society to keep and which to reexamine to see if they can be done better. Aviation safety is one of those things our society does know how to do well, and that seems very much worth keeping to me. Overall I trust aviation engineers to find ways to do hydrogen airships safely.
Part of the safety focus is from sticking so many people in the same fuselage - which, being big, has no individual rescue equipment and cannot be brought down by parachute either - so nothing critical is allowed to fail.
Side note: that’s not the only possible model, however - one can also design heavier than air craft that are smaller, almost passively safe (falling controllably without power, at somewhat above parachute speed), and design small aircraft that have rescue systems (parachutes which can land the whole aircraft).
Size itself is then a function of economic realities (air travel has undergone explosive growth).
Blimps would have to somehow fit in. Having considerable air resistance, blimps cannot travel as fast. Being unable to travel as fast, they would fall behind at moving X people per hour - while a blimp makes one roundtrip, a jet aircraft would make multiple roundtrips.
If however a jet aircraft is deemed environmentally unsustainable on account of fuel use - then the milestone to compare a blimp against will be a propeller-electric aircraft. Which is more limited in speed, requires charging time, is more limited in range - and therefore makes less roundtrips in an unit of time.
From one viewpoint then, the success of airships thus depends on whether fast aircraft can reduce their environmental footprint. If they can, blimps will not be widespread. If they cannot, blimps might become widespread.
Overall, a fast airplane is effective at getting results (transporting people) but not necessarily efficient at doing that. There is perhaps only one aspect where a high-powered aircraft is more efficient… use of space. But space is not a scarce resource in the atmosphere. Only on the runway.
Out of the previous considerations, I come to the conclusion: blimps probably won’t replace airplanes. Especially for longer trips, having to wait less is what makes people prefer speedier travel. Blimps cannot provide that. However, airships might carve out a niche for servicing shorter routes and local traffic.
Do you have any idea how much fusion you’d have to do to have it be a significant source of helium?
*edit: I was curious but had to guess ranges to do the maths. To fill a single Flying Whale airship, a 2 GW fusion plant needs to run between 90 and 850 years.
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