Ryan Cooper on "The Return of Airships"

Ryan Cooper of The Week recently wrote about "The return of the airship," and it seemed like a good occasion on which to launch this... well, effort. For now, it's a blog. I hope it will turn out to be a lot more than a blog. It's an effort to catalyze the emergence of a giant airship industry, by getting first a critical mass of thought and brainpower together, then mobilizing a critical mass of money. I know something about airships, because years ago, I was part of a nascent airship company called Loft Aeronautics. See here a blog that spun off from that endeavor. But more on my goals and strategy later. Cooper's article is a good introduction to giant airships.

Cooper starts with carbon emissions.

Transportation is now the biggest single source of U.S. greenhouse gas emissions, having recently passed electricity generation. Worse, zero-carbon transportation technology is only in its early stages — especially for air travel and shipping, which accounts for large and growing share of emissions.

Steampunk fans and climate hawks alike want to know: what about airships? After investigating the subject for a time, I've come to a tentative conclusion that airships could indeed play an important role in a zero-carbon transportation infrastructure — but probably not in the form of romantic luxury travel. Big and weird cargo shipping might just be where the airship does best.

Now, reducing the carbon footprint of transportation is a fine reason to care about airships, but I worry that people will think of airships like recycling, and imagine a future where people in the future will fly on airships rather than airplanes the way people today sort out their plastic and cardboard trash for recycling, suffering the inconvenience because of conscience or because the government forces them to. From a variety of consultations and correspondences, I believe that giant airships, once they get over the initial R&D hump, will be quite competitive on cost alone with existing modes of transportation. Zero carbon is a nice perk but shouldn't be the main motive.

And while Cooper is right that romantic luxury airship cruises aren't particularly important for reducing greenhouse gas emissions, they're a plausible and fascinating potential market for giant airships.

Readers new to airships will appreciate this background info:

Airships are, of course, aircraft which use a large envelope of lighter-than-air gas, typically hydrogen or helium, to provide most or all of their lift. There are three basic types: non-rigid (a blimp), or semi-rigid (with a partial supporting structure), or rigid (with a complete supporting structure). There is also the hybrid airship, which is slightly heavier than air and uses traditional wings or rotors to provide lift and control.

Cooper then summarizes the advantages of giant airships, or to be more precise, the prospective advantages of giant airships that haven't been built yet but that technologists have plausibly imagined:

Airships have several important advantages. First is that with the envelope (that is, the ballon-like structure where the gas goes) providing lift, there is no need to expend fuel to maintain flight. Second is low-speed maneuverability, meaning they don't require as much infrastructure as airplanes — no runway for instance, or only a short one in the case of hybrids. Third is high potential lifting power — the largest new designs could theoretically carry 500 tons or more, in the same league as the largest cargo planes. Fourth is very high cargo volume — a heavy lift airship would have to be very large, and so would be able to accommodate a correspondingly huge cargo bay.

Yes. Let me unpack that a bit.

1. Most of the fuel that airplanes burn simply keeps the airplane in the air, rather than moving it forward. Airships don't need fuel for lift, only for propulsion, so they can be much more fuel efficient.

2. Rather than "low-speed maneuverability," I'd talk about "hover capabilities" and "vertical takeoff and landing." "Infrastructure independence" is a nice slogan, too, though taken literally, it applies to only some airship designs at best. A pure (as opposed to hybrid) airship can stand still in the air. Planes have to be in forward motion whenever they're in the air, because the flow of air over their wings gives them lift and makes them fly, so they can't hover and need runways to land. Airships don't. The name of this blog, "The Roadless Revolution," is about that feature, which I'll unpack in a future post.

3. As far as I know, the 500-ton limit isn't hard and fast. Loft was envisioning airships with a 1,000-ton payload. The main constraint is just how big you can build. The bigger the airship, the more lifting gas, and the larger the payload can be. But the proposed airship designs are very big.

4. Just to be clear, the cargo bay is much smaller than the airship. The vast majority of the airship's volume has to be filled with a lifting gas, hydrogen or helium. But the cargo bay can still be tens or hundreds of thousands of cubic feet, with all dimensions much larger than a highway lane.

However, airships have large downsides as well. The biggest one by far is drag — with an envelope many times larger than even the biggest planes, and drag increasing with the square of velocity, the amount of power required to move an airship will quickly eat into its efficiency advantage from floating — even at highway speeds (Germany's famous Graf Zeppelin had a top speed of 128 mph, but generally cruised at about 70 when it traversed the globe in the 1920s and '30s). Size itself is a problem as well. Airships need to be big to be useful, and wrangling lots of them in an airport or port will be tricky.

When I was at Loft Aeronautics, we talked a lot about optimum speed. Initially, other teammates wanted to fly the airship at 70 mph or less, for the sake of fuel efficiency. I crunched the numbers and ended up thinking that, on cargo routes, you'd always want to fly top speed, because the extra fuel consumption was less important than economizing the time of an expensive piece of capital. But of course, it's nice that you can always gain fuel efficiency by slowing down. Slower speeds might get more economical if capital costs come down or fuel costs rise.

As for "wrangling lots of [airships] into an airport or port"-- well, sort of. But, going back to the point infrastructure independence point above, you don't really need an airport or port, at any rate not on the scale we're accustomed to today. The advent of giant airships would herald an age of comparatively decentralized travel. Also, airships' ability to hover would be helpful in managing traffic through some sort of transshipment facility.

As big, relatively fragile objects, they are also more vulnerable to weather than airplanes — though that should be less of an issue with modern weather prediction.

Yes. Airships have regularly been destroyed by weather events, such as sudden strong winds, since the days of Count Zeppelin. This is a big challenge for the technologists to overcome before airships can gain a foothold in global logistics.

He notes in passing the hydrogen vs. helium issue, and sides with hydrogen:

The choice of gas is a particularly thorny question. As a technical matter helium is objectively superior, providing almost as much lift as hydrogen while being non-flammable. However, helium is much, much more expensive than hydrogen, and as a non-renewable resource arguably ought to be reserved for scientific research. (You need a lot of helium to fill up a big airship.)...

Hydrogen is the riskier but cheaper choice, but ultimately it should almost certainly be possible to develop airship technology to the point where it posed no real threat. If airplanes can fly around carrying tens of thousands of gallons of highly flammable fuel, then we ought to be able to work out how to fly hydrogen airships.

Safety is a huge challenge, yet not as much as it might be perceived, and it shouldn't be insurmountable:

The spectacular destruction of the Hindenburg (whose hydrogen envelope caught fire) basically ended civilian airship travel at a stroke. However, this was more about saturation coverage and mass media than it was about objective danger. The eye-popping newsreels, photographs, and heart-rending live radio broadcast obscured the fact that airplane travel was also quite dangerous at the time (not to mention the fact that most of the Hindenburg passengers actually survived). There were at the time, and would continue to be, mass casualty disasters from civilian airplane flights, often due to fuel catching fire and burning everyone alive after a crash. But they weren't covered in the same way, and so did not create an impression of extreme danger. Meanwhile, as government regulators, airplane manufacturers, and airlines got extremely good at flying, the rate of crashes was brought down to nearly zero, and the public came to correctly believe that the risk of flying was small.

Hydrogen burns up, passengers are down, so an airship explosion can be horrifyingly spectacular and yet non-fatal.

Since a lot of prospective airship applications are weird/speculative or small-scale, I like it that Cooper focuses on the huge market that I think will really make airship investments pay off:

At any rate, all this points to a particular use case for the airship: moving heavy and/or bulky cargo directly from point to point, at a speed faster than cargo ships but slower than planes, using sustainable biofuels, fuel cells, or electric motors (perhaps even substantially solar-powered in the latter case — if they ever figure out how to produce painted solar panels, a big envelope could generate a lot of power).

Airships can't go nearly as fast as airplanes; they could never carry truly time-sensitive cargo or compete with passenger flights. They are probably best at about 30-70 miles per hour, to keep drag down. But that's a lot faster than container ships — indeed, shipping companies have themselves taken to slowing their big ships down to 12-14 miles per hour to save on fuel. They would be particularly useful for medium-urgent goods that need to be shipped across the ocean and then flown to their final destination, since they could skip the port bottleneck...

Quite a considerable portion of some shipping routes could theoretically be taken up in this manner. A study of shipping between Hong Kong and the U.S. and Europe found they could replace up to half of the "dedicated cargo aircraft" capacity. And since cargo planes are generally the oldest and least efficient models in the sky, replacing them with zero-carbon airships would be a particular benefit.

Yes, though Cooper sells the potential of airship passenger flights a little short here. It's true that airships could never compete with passenger airplanes on speed. They probably could compete on price, but plane tickets are really pretty cheap anyway, e.g., New York to Chicago for under $200. But airships could compete on comfort, or offer "flying hotel" services-- board in New York, get a nice night's sleep in a comfy cabin, and wake up in Chicago. They could compete for the business of families and seniors. They might compete with planes in developing countries where plane ticket prices seem more burdensome. And, requiring less infrastructure, they could open up new destinations where there isn't an airport. You could also bring more luggage: airship-motorcycle intermodality is an exciting possibility.

He then brings up what at Loft we used to call the "outsize cargo" market:

They would probably be best of all at taking very large or awkward cargoes directly from the place of manufacture to their destinations, especially for remote locations. For instance, logging and mining companies that use very large pieces of equipment typically have to disassemble the machine after testing at the factory, ship the (still big) individual pieces part of the way on trains and giant trucks, and then put it all back together out in the field. The expense, time, labor, and resources required are immense. But a heavy lift airship could pick up the assembled item, drop it off directly where needed, and then pick it up again when it's done. Imagine also taking a big bundle of wind turbine blades directly to the wind farm construction site, instead of having to carefully manhandle them down the interstate one by one.

Lockheed Martin is developing a line of hybrid airships and selling them on exactly these grounds, and has reportedly secured a $480 million letter of intent to sell 12 of them.

When I was research airship markets, I found that it was much harder to research the size of the outsize cargo market than the trans-oceanic shipping (TOS) market. Routine trans-oceanic shipping is a huge market already, fairly well served by ships and planes, but with a big hole in the middle of the transport options menu for the middle-cost, middle-speed transport options represented by trucking and rail when moving goods over land. If airships can capture that, as it seems they should be able to do, that could well be enough to make it a trillion dollar industry by market cap, if not by revenue. For outsize cargo, by contrast, airships can offer to do things that you can't do at all with current transport technology, or that can be done only with extreme difficulty and inconvenience. And yet if airships open up a new era of gigantic manufacturing, that could be very important.

Cooper leaves his readers by projecting tentatively what it will take to make it happen.

On paper, this all sounds pretty good. But it will require sustained investment and policy attention. New technologies always have to climb the development and implementation ladder, meaning lots of mistakes and setbacks as best practices are ironed out and supply chains built. We were once quite a ways up that ladder — witness the Graf Zeppelin, which traveled over a million miles, including an around-the-world trip, before being scrapped — but much progress has been lost since then. At a minimum, that will mean lots of government R&D grants to spin up the new industry. But if that happens, the results could be a very big, very quiet success.

I diagree that "at a minimum, that will mean lots of government R&D grants to spin up the new industry." I know enough about the scale of the airship challenge and the capacity of private sector philanthropy and capitalism to be confident that the private sector can do this alone. Government R&D grants would probably be helpful, and might be well-advised. Certainly, for those who contemplate a Green New Deal (which I find catastrophically overambitious), investment in airship R&D is likely to be more impactful for the money spent (or the GDP sacrificed) than a lot of other things government can do for the climate. But airship champions-- such as I'm trying to be-- shouldn't despair if taxpayers don't come to our aid, and probably have better things to do than ask.

Yet I do think we need badly to publicize the airship future for other reasons. One is the conservatism of finance. The advent of the new age of giant airships-- the Roadless Revolution-- will require, above all, significant engagement by very rich people and/or corporations. And I believe there's a certain inherent conservatism in people with money, because they face the winner's curse problem, the temptation to spend their money on things that happen to sound good to them and usually aren't because of a subtle kind of adverse selection, every day. Public opinion enthusiasm for the Roadless Revolution will enable people with big money, when opportunities to invest in giant airships come along, to follow public opinion rather than trust their own judgment. Also, while I don't think government subsidies to R&D are necessary, mistrustful governments could stop the Roadless Revolution in a thousand ways, intentionally or unintentionally. At the end of the day, the giant airship industry will put things in the sky that people could choose to regard as an eyesore or a menace, and demand that legislators ban. So it's important to prepare people to welcome them when they arrive.

I plan to write a lot of posts here over the next few months expounding all facets of the vision. And I also want to persuade through other channels. So please feel free to connect. Comments are welcome, or you can call me at two-o-seven, five-five-seven, zero-zero-seven-seven, or e-mail me at lancelotfinn -- at -- gmail -- dot -- com.