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writing:airships [2025/11/13 16:10] – JacobCoffinWriteswriting:airships [2025/11/13 16:43] (current) – JacobCoffinWrites
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 For many of us, airships occupy a sort of odd speculative space left open where materials science, aviation, engineering, computerization, and air traffic control have all improved massively while airships themselves have seen comparatively little use. That leaves a lot of room for argument and a handful of startups that promise that everything is fixed now and they can slot neatly into this low carbon, slower than planes, faster than ships, with fewer transfers, cargo or passenger niche.  For many of us, airships occupy a sort of odd speculative space left open where materials science, aviation, engineering, computerization, and air traffic control have all improved massively while airships themselves have seen comparatively little use. That leaves a lot of room for argument and a handful of startups that promise that everything is fixed now and they can slot neatly into this low carbon, slower than planes, faster than ships, with fewer transfers, cargo or passenger niche. 
  
-The interesting thing is that airships didn't actually vanish with the Hindenburg, though there are certainly fewer examples in operation, and many of those that remained were military. Still, these airships give us some solid evidence backing up the kind of improvements we expect from massively more powerful motors, better materials, etc.+The interesting thing is that airships didn't actually vanish with the Hindenburg. Airships in various forms have been operating in military, research, and development/prototype roles right up to the present day, and industry and the public sector have continued to evaluate their performance and relevant technological developments. These airships give us some solid evidence to use when evaluating claims from startups, and in planning how we depict modern airships in fiction.
  
  
 ==== Misconceptions ==== ==== Misconceptions ====
 +
 +There are a number of misconceptions we should address up front, most of which come from the poor performance of historical airships from the dawn of aviation when compared to modern aircraft, or from pop culture:
  
 === Airships are unsafe === === Airships are unsafe ===
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 even hydrogen airship accidents (which are far more lethal than helium airship accidents) were about half as lethal as airplane crashes of the same time period.  even hydrogen airship accidents (which are far more lethal than helium airship accidents) were about half as lethal as airplane crashes of the same time period. 
 Considering this was the 1900s-1930s, that’s a really low bar—aviation didn’t become even remotely safe until about the 1970s—but it’s worth noting that Zeppelin’s been flying its NT model airships for nearly 30 years without a single fatal accident.  Considering this was the 1900s-1930s, that’s a really low bar—aviation didn’t become even remotely safe until about the 1970s—but it’s worth noting that Zeppelin’s been flying its NT model airships for nearly 30 years without a single fatal accident. 
 +
 +
 +
 +**Hydrogen and Modern Airships**
 +From the data ranging from 1900-1945, we can see that hydrogen airships started off being about 10 times safer than airplanes (engines were horrendously unreliable back then, and an airship reverting to being a balloon, even a flammable balloon, during engine failure was preferable to becoming a plummeting brick), until gradually airplanes became safer at an even faster rate than hydrogen airships were improving, catching up to them in safety around the mid-1930s. Then the Hindenburg disaster happened in 1937, and hydrogen ceased being used shortly thereafter. As helium blimps were being used in Word War II in large numbers, the data show they were about four times safer than hydrogen airships, and also general aviation of the same time period. Even today, though airships are quite rare, they remain considerably safer than the average aircraft of their same general mass and regulatory category.
 +
 +No airships have ever been engineered to the unbelievably exacting and expensive degree that a modern commercial airliner is, though, and those are like night and day compared to general aviation safety—in other words, airships tend to be safer than private planes, but of a similar cost and complexity, and neither hold a candle to the astounding safety record of commercial airliners.
 +
 +The potential for airships to be designed as safe as commercial airliners exists, I believe. If airplanes could overcome their early deficiencies to achieve the absurd safety of commercial airliners, and likewise submarines could be engineered from an absolute deathtrap far more unsafe than even hydrogen-filled World War One airships to the exceedingly sound military vessels they are today (with the U.S. Navy’s last fatal submarine loss being in 1968), then I don’t see why not.
 +
 +That being said, it would take a huge amount of testing to make sure that a hydrogen airship was fireproof under all edge cases and conceivable flight conditions. It would require active fire suppression systems (alarms, hydrogen and oxygen detectors, fire extinguishers, etc.) and even more extensive passive measures (proper electrical conductivity, fireproof materials, a double hull of inert gas like helium or nitrogen and/or a direct gaseous mixture to alter the hydrogen’s explosive and ignition range even when exposed to air, etc.) to achieve a sufficient level of safety. Such things are possible—airliners and fuel tankers now explode far less often, thanks to inerting the fuel vapors in their tanks with nitrogen or carbon dioxide. 
  
  
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 The LCA60T — an airship currently under development as a flying crane, that has the same operating wind limits as a helicopter or conventional crane. It can do its hovering cargo operations 250-320 days out of the year, depending on the location.  The LCA60T — an airship currently under development as a flying crane, that has the same operating wind limits as a helicopter or conventional crane. It can do its hovering cargo operations 250-320 days out of the year, depending on the location. 
  
 +
 +They’re proportionally more affected by the wind because they’re slower than airplanes, but that doesn’t mean an airship has to be as fast or powerful as a plane to be able to operate in similar wind conditions. In fact, the Navy’s radar airships during the Cold War were able to fly in 60-knot blizzards and thunderstorms that grounded all other military and civilian planes, with an astounding inclement weather availability rate of 88%. They were able to operate like that because they didn’t fear crosswinds or stalls while landing, and could wait for days if necessary without running out of fuel, and thus could afford to take it slow. 
  
  
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 Modern airships address changes in weight in several ways, probably the simplest of which (aside from releasing the lift gas, or heating it during flight and letting it cool on the ground) being to just fly the ship heavier than air by the weight of the payload. With the structure still buoyed by helium, it remains quite efficient even while supporting the cargo with aerodynamic lift and/or vectored thrust, and then you can simply offload the payload at the destination, assuming it’s not able to take on any return cargo or extra fuel or water ballast or anything of the kind — sort of a “deliver your max payload to the middle of nowhere and come back” solution, which should hopefully not be needed too much in practice.  Modern airships address changes in weight in several ways, probably the simplest of which (aside from releasing the lift gas, or heating it during flight and letting it cool on the ground) being to just fly the ship heavier than air by the weight of the payload. With the structure still buoyed by helium, it remains quite efficient even while supporting the cargo with aerodynamic lift and/or vectored thrust, and then you can simply offload the payload at the destination, assuming it’s not able to take on any return cargo or extra fuel or water ballast or anything of the kind — sort of a “deliver your max payload to the middle of nowhere and come back” solution, which should hopefully not be needed too much in practice. 
  
 +=== Airships aren't fuel efficient ===
  
 +In terms of transport coefficient, a helicopter has a value of about 1, an airplane has a value of 4, and even airships from over 100 years ago could have values over 16. They are very fuel efficient, nearly as much as a ship. For a 200-ton gross weight airship like the one pictured above, it only takes about 600 horsepower to go 40 mph, 4,300 horsepower to go 80 mph, and 23,000 horsepower to go 140 mph—and a cargo plane like the Atlas A400M has 44,000 horsepower. It’s got a top speed of 513 mph, sure, but it also carries only a little over half as much cargo as the Flying Whales airship, 37 tons vs. 66 tons. So not only does it burn a lot more fuel, but it also has to take multiple trips to carry the same amount, and that's against an airship designed as a precision flying crane rather than for cargo transportation.
  
  
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 Much in the same way we know that it is possible to build reliable, profitable high-speed rail, even if the concept of such a thing seems wildly out of reach to people in places where it doesn’t exist.  Much in the same way we know that it is possible to build reliable, profitable high-speed rail, even if the concept of such a thing seems wildly out of reach to people in places where it doesn’t exist. 
 +
 +=== Airships can't compete with other forms of transportation ===
 +
 +This has some overlap with the Airship Niche section below, but 
 +
  
  
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 This section gathers broad categories of design and intended use This section gathers broad categories of design and intended use
 +
 +
 +=== Flying Cranes: ===
 +
 +**The LCA60T and Flying Whales**
 +
 +This particular airship is highly specialized for maneuverability and aircrane operations at the expense of speed and range. It has the same operating wind limits as a normal crane or helicopter. 75% of its 32 electric motors and propellers are fixed in place exclusively for thrust vectoring purposes, only 25% are fixed for forward propulsion (and even those can use differential thrust for steering). Turning quickly isn’t really an issue in this case, as compared to classical Zeppelins that had only their rudders to turn with.
 +
 +Similarly, large ships used to be cripplingly dependent on tugboats to maneuver, and were incredibly slow to turn, before the invention of things like azimuth propulsors and bow thrusters that now allow a cruise ship to pivot 360° within its own length. 
 +
 +this particular ship is highly specialized for air crane operations over short distances, not efficient transport from A to B. It’s quite slow, even for an airship, with a top speed of about 60 mph. An actual dedicated cargo transport airship would be bigger, sleeker, and more powerful, with an optimal cruising speed anywhere between 70 and 170 miles per hour depending on the route length, and a payload in the hundreds of tons. 
 +
 +designed for maneuverability and transporting oversized loads, and is not suitable for long-distance rapid or heavy freight transport
 +
 +
 +**Kelluu**
 +The Finnish company Kelluu has a small fleet of autonomous hydrogen-lifted and hydrogen-powered survey airships. They are much safer to use hydrogen with, as unlike other airships, they are designed to have no internal areas where oxygen and hydrogen could mix and become flammable.
  
  
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 With ships, they can compete sometimes (fresh food, high-value manufactured goods, etc), with freight trains, definitely not, but trucks? The largest airships can compete with trucks in terms of cargo cost per ton/mile, and are considerably faster, in addition to their capability to carry things too bulky and/or too heavy for a truck. That won’t detract from trucks’ ability to transport things last-mile, of course, but there’s certainly some useful applications.  With ships, they can compete sometimes (fresh food, high-value manufactured goods, etc), with freight trains, definitely not, but trucks? The largest airships can compete with trucks in terms of cargo cost per ton/mile, and are considerably faster, in addition to their capability to carry things too bulky and/or too heavy for a truck. That won’t detract from trucks’ ability to transport things last-mile, of course, but there’s certainly some useful applications. 
 +
 +
 +when it comes to comparing transport capacities to trains or ships, the real question is what you’re transporting.
 +
 +Ships and trains are unbeatable when it comes to transporting cargo that is both extremely cheap and extremely heavy, such as crude oil and raw mineral ore. But that’s not all or even most of what they’re tasked with carrying. More expensive cargoes like finished manufactured goods and fresh food are often limited by volume, not weight, and vehicles carrying human passengers are always limited by volume, not weight. The average Amtrak passenger train and average ferry both carry around 300 passengers, with outliers carrying 1,000 and 5,200 people, respectively.
 +
 +If we are to assume the practical economic limit for an airship’s size to be around that of the Hindenburg, past which it would be more practical to just use two airships rather than an ultra-huge one, then the limits of an airship’s capabilities would be ably demonstrated by Lockheed-Martin’s slightly smaller hybrid rigid airship concept from 1999. It would have a range of 4,000 nautical miles, a cruise speed of 150 knots/180 miles per hour, a cargo capacity of 500 tons, and a cargo area of 65,000 square feet. That would put it just shy of the largest ferries in terms of passenger capacity, with space per passenger more similar to a train than a plane. However, it would be ten times faster than the ferry, and four times faster than Amtrak. 
  
  
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 ==== Lift Gas Types, Sources, and Storage Requirements ==== ==== Lift Gas Types, Sources, and Storage Requirements ====
  
 +=== Helium ===
  
 +Cheap, abundant helium won’t run out until natural gas does, or possibly even after—since helium is often found in otherwise completely economically useless pockets of underground nitrogen, not just natural gas. In other words, nothing to worry about for hundreds of years. The shortages we currently face are an infrastructure problem, not a supply problem. Even once that’s gone, you can still get helium from the atmosphere, but presumably by that point we’d have implemented fireproofing methods to safely contain hydrogen. There are already two main methods to do so, it’s just a matter of properly engineering, testing, and certifying them. 
  
 +Helium makes up a relatively constant portion of the atmospheric gas mixture, and has for hundreds of millions of years, due to its constant production via radioactive decay in the earth’s core. The atmosphere is like a full bucket underneath a dripping spigot—it’s constantly losing water over the edge, yes, but it’s also not being emptied either.
 +
 +The problem is that we waste literally 99% of the helium present in natural gas, simply because we don’t have the infrastructure installed to extract it before use. You could also distill helium from the air itself, but that takes about 3-5 times more energy due to the lower concentration, and with our current atmospheric fractional distillation capacity we’d only be able to meet about 1% of global helium demand (coincidentally about the portion that airships use). 
 +
 +People are actually drilling helium wells now, it is non-refundable but quite abundant.. Other deposits exist in Alberta and Wyoming, just within north America. 
 +https://www.minnpost.com/other-nonprofit-media/2024/07/what-to-know-about-minnesotas-richest-in-the-world-helium-deposit/
 +
 +=== Hydrogen ===
 +
 +Oh the humanity! 
  
 The astronomical improvements in aviation safety would more than make up for the difference in safety between hydrogen and helium, such that a properly designed modern hydrogen airship would be incomparably safer than a historical helium one, but that doesn’t change the fact that hydrogen is always going to be more dangerous.  The astronomical improvements in aviation safety would more than make up for the difference in safety between hydrogen and helium, such that a properly designed modern hydrogen airship would be incomparably safer than a historical helium one, but that doesn’t change the fact that hydrogen is always going to be more dangerous. 
  
 +
 +
 +The other downside is that while hydrogen is not a greenhouse gas in itself but it competes for hydroxyl ions in the atmosphere with methane, a powerful greenhouse gas. Basically, every hydrogen molecule in the atmosphere extends the lifespan of one methane molecule. [[https://en.wikipedia.org/wiki/Hydroxyl_radical|The hydroxyl radical is often referred to as the "detergent" of the troposphere because it reacts with many pollutants, often acting as the first step to their removal.]]