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.
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.
Blimps are far worse than airships; the fundamental advantage of airships is that they scale up well (doubling the size nets you 8x the volume), which blimps just don’t. And blimps are far less safe, due to their gas bags needing to be pressurized where airships’ gas bags can be unpressurized. More specifically, if you puncture a pressurized gasbag, then its contents spray out due to the pressure, which in the context of hydrogen would mean it rapidly mixes itself into large amounts of hydroxygen just begging to explode, whereas unpressurized gasbags will just slowly diffuse hydrogen like piss in water. Still potentially dangerous, but far less so.
Weirdly, when it comes to cargo airshipping, airships are actually faster than cargo freight (not to be confused with parcel freight, which is what post (e.g. Amazon packages) uses). Cargo freight takes 4-5 days, which airships can easily beat via shipping point-to-point.
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.
Blimps are far worse than airships; the fundamental advantage of airships is that they scale up well (doubling the size nets you 8x the volume), which blimps just don’t. And blimps are far less safe, due to their gas bags needing to be pressurized where airships’ gas bags can be unpressurized. More specifically, if you puncture a pressurized gasbag, then its contents spray out due to the pressure, which in the context of hydrogen would mean it rapidly mixes itself into large amounts of hydroxygen just begging to explode, whereas unpressurized gasbags will just slowly diffuse hydrogen like piss in water. Still potentially dangerous, but far less so.
Weirdly, when it comes to cargo airshipping, airships are actually faster than cargo freight (not to be confused with parcel freight, which is what post (e.g. Amazon packages) uses). Cargo freight takes 4-5 days, which airships can easily beat via shipping point-to-point.
Ah, sorry, I was careless with terminology.
Throughout my post, I was thinking of rigid-envelope airships, but at some point, referred to them as blimps. Apologies.
About the only role I would give to a non-rigid airship is “a tethered observation post”. :)