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Helium Hokum: Why Airships Will Never Be Part of Our Transportation Infrastructure

The views expressed are those of the author and are not necessarily those of Scientific American.


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We’ve all been fascinated by balloons. As children we used to get a balloon at the circus, and then suddenly, we’re magically mystified by the ability of a toy to do the non-obvious and seemingly impossible: Float in something that we ignore and pay no attention to until something floats "in" it.

Torricelli proved the existence of a vacuum by using a closed tube and some mercury, a device we now called a barometer. He recorded his observations thus: "Noi viviamo sommersi nel fondo d’un pelago d’aria"—we live submerged at the bottom of a sea of air.

Normal kids discover kites and leave toy balloons behind. They learn to make use of sticks, paper, string, and the moving air to make things go up, up, and away without the complexity of finding a circus—and without the inevitable disappointment of the toy balloon, which quickly looses its umph and eventually sits dead on the floor. Happily, kites provide a universal satisfaction, and they can even be made to fly when there is no wind, simply by running.

Unless of course you’re an oddball like me. I loved balloons long after it was "cool." Why? Because it was fun to put a paper cup on the string of my balloon and load the cup with paper clips and then individual staples until it would float just so in the middle of the family room. But not to worry; I did the balloon thing and kite thing at the same time: Balloons for the occasional fascination, and kites for dependable fun—both with an underlying eye to the science of their operation, and always asking, "Why?"

In the history of technology of Western civilization, the balloon was invented twice, in Paris, in the last six months of 1783. These events are usually, and unfortunately, relegated to footnotes, and enjoy an early chapter at best, of most aviation history books. Even the National Air and Space Museum in Washington, D.C., has eliminated the room dedicated to mankind’s first successful voyages into the air since these are apparently of little interest, in the museum’s opinion. Never mind that the events of those six months in Paris were, essentially, a miniature precursor of the "Space Race" of the 20th century.

Like most things in transportation technology, it began with what we would today call scale models. This quickly progressed to the first full-sized manned machines. And like the Space Race, there were two contenders: In one corner were the brothers Joseph-Michel and Jacques-Étienne Montgolfier (heirs to a more than lucrative family paper manufacturing enterprise), and in the other corner, Professor Jacques Alexandre César Charles of the Conservatoire National des Arts et Métiers.

The Montgolfier’s were well aware—like most of the human race for thousands or even tens of thousands of years before them—that smoke rises from a fire. They concluded, incorrectly, that there was a special gas in the smoke that caused it to rise. Without any experimental evidence of its existence, they proudly named it Montgolfier Gas, claiming it contained a special property which they called levité.

Subsequently they proceeded to contrive a means to contain it, using (of course) the product that they manufactured: paper. They applied their paper to the inside of a large bag made of cloth; and, in an additional effort to contain their trade-marked special secret gas, they also went to great lengths to ensure that the fires they used to fill their gas bags were dark and sooty—the better to coat the paper and keep their special secret gas contained.

Professor Charles, on the other hand, already knew that hydrogen was lighter than air, and he how to produce it. He’d studied the work of Robert Boyle, who had produced hydrogen in England more than a century before by combining metal and acid. Charles also knew that if he could find a way to make a fabric impermeable to hydrogen, he could make a balloon too. But where to find such a material, n’est-ce pas? Like all good research scientists—or so the story goes—he brought the problem to the attention of his colleagues. This included the brothers Anne-Jean and Marie-Noel Robert, builders of scientific instruments.

The Robert brothers quickly came up with a solution to Charles’ problem. In amazingly short order, they delivered an impermeable fabric coated with latex rubber—a process they had developed as part of their secret, high-tech, black market manufacture of condoms—then very much illegal in devout 18th-century Catholic France.

I suspect that, as a chemist, Charles probably knew that the Montgolfiers and their balloon were both full of hot air, figuratively and literally. As a chemist, he probably had a pretty good idea that there was no special gas with the property of "levity" emanating from a common fire. After all, Charles studied the effect of temperature on air, including that heated air tends to rise. Thus, the scientific principle describing how much a Montgolfier hot air balloon can lift is called Charles’ Law.

Thus, in a mere six months, the balloon went from concept to prototype; and, just slightly over a year later, the English Channel was crossed for the first time by air in a hydrogen filled balloon by Jean-Pierre Blanchard.

In that very same six-month period of 1783, a young Lieutenant in the French Army Corps. of Engineers—a chap named Jean Baptiste Marie Charles Meusnier de la Place—immediately recognized the obvious: Elongate the ballon (so named because it resembled the hand-blown glass retort used by chemists of the day) so that it’s resistance to motion would be reduced; put a small air bag, or ballonet, inside the balloon to help it keep its shape; add a rudder to make it dirigable (steerable); and add large diameter propellers (just like windmills, but in reverse) powered via a crankshaft turned the ballon’s crew.

Nice idea, but not practical. It took the watermelon-smashing comedian Gallagher, who enlisted Bill Watson and his colleagues to finally make the first human-powered blimp, the White Dwarf, two centuries later in 1984. It was an entertaining exercise for sure; but it was, as the Germans say, nur für Spaß—only for fun.

So Meusnier’s airship had to wait for a suitable engine to be developed.

In 1845, a certain chap by the name of Rufus Porter started a weekly magazine called Scientific American. Four years later, in 1849, he proposed the use of steam engines to power navigable balloons. This was a year after John Stringfellow built a working model of Henson’s proposed "aerial steam carriage," creating the first successful powered prototype airplane in history.

Three years on, Henri Giffard achieved Rufus Porter’s proposal. Of course, Giffard’s friends advised him against such folly. They knew the dangers hydrogen could present when combined with the sparks thrown up the smokestacks of steam engines devised by the likes of George Stephenson. After all, Pilâtre de Rozier had built a hybrid balloon combining fire-fed hot air with hydrogen his 1785 attempt to cross the English Channel, achieving the expected result: disaster and death. Undeterred, however, Giffard made a meritage of an elongated balloon, rudder and a propeller, driven by the steam engine that Meusnier longed for—achieving all of about three miles per hour, and barely managing to return from his launch point in a dead calm.

Fast forward to 1898. The Brazilian ex-pat Alberto Santos-Dumont, again in Paris, combined his love of motorcycle racing and ballooning to make a ballon dirigable of his own devising—the first successful aircraft to be propelled by an internal combustion engine. A mere year and a bit later, he won the Deutsch Prize for flying from the Paris Aero Club around the Eiffel Tower and back in less than 30 minutes. Parenthetically, because he was too busy with the controls of his machine to check his pocket watch, he did not know if he’d made it in time. He mentioned this to his friend Louis Cartier, and as a result, to this day Cartier SA still sell the "Santos" wrist watch—a mere $7,000 a copy, last time I checked. And for a score more years, if you wanted to get to somewhere far away and come back, the airship was the way to go.

But airships got left behind. Why? They have an Achilles’ heel. No, it’s not the weather, hydrogen, or the materials of the day—and it’s not some conspiracy or a crewman with a bomb on the Hindenburg ruining it for everybody. Like a lot of things, the facts are simple and scientific, and thus boring—unless you’re intrigued by simple scientific facts. Either way it’s this: airships are inefficient.

The purpose of transportation is to get a thing from one place to another. The measure of any vehicle’s efficiency—be it by land or by sea or even by air—is how much it carries vs. how hard you have to push it and how fast it goes. At the end of the day, we all want to get it there fast, and we all want to get it there cheap.

In 1950, Theodore von Kármán, one of the founding fathers of the science of aeronautical engineering, published a paper entitled What Price Speed? Specific Power Required for Propulsion of Vehicles. His work so timeless in its basics that it was recently updated by members of the Department of Mechanical Engineering of Imperial College London as What Price Speed—Revisited. In What Price Speed?, von Kármán showed that if you take a vehicle’s horsepower divided by it’s weight and speed you can see how efficient that vehicle is compared to other vehicles. Von Kármán used the total weight of the vehicles he considered because that information was readily available to him at the time. Today, we can more easily take this a step further, dividing the vehicle’s horsepower by the weight of the cargo it carries and its speed to gain even more insight.

The following graph does just that, and includes data from some key means of transportation. The original by von Kármán is plotted on a log-log scale and includes performance trends vs. speed. But let’s keep things simple, and what engineers and scientists call a "first order of magnitude" analysis, which is a fancy way of saying let’s check things out with some simple, rough, easy to calculate numbers. Back before computers were everywhere—when you had to do things by hand with pencil and paper and a slide rule—this is what people did: Get some rough numbers to see if one thing is better or worse than something else, and toss out the bad ideas without wasting valuable time crunching useless numbers—let alone actually build the thing.

So, using information you can readily get today via the Internet, I’ve plotted a few examples: A container ship, a train, a truck, a couple of airplanes, a couple of old-school airships, and a couple of "modern" airships of the type that keep getting some press every few years, again and again, over the last 40 years or so. These "new" airships are now called "hybrids" because they try to augment the lift of their gasbags with a bit of aerodynamic lift—in short, they try to be part balloon and part airplane at the same time. Never mind that Charles P. Burgess correctly argued from simple engineering principles in Chapter 10, "Common Airship Fallacies", of his 1927 book Airship Design, that this was, and remains, pure folly. But never mind what he said; how about we judge for ourselves?

If you look up how much power each vehicle has, and divide that by what it can carry and how fast it goes, and put those points on a graph, you can learn a lot. You can see, for instance, that a train is roughly as efficient as a container ship—but it goes much faster.

For example, all that’s left on the northern leg of the Wabash & Erie Canal—built in the early 1800s and, at 460 miles long, is the longest canal ever built in North America—is now just a over-sized ditch along highway US 24 in Indiana and Ohio. A very short part of that canal, with a working lock and a canal boat has been reconstructed as a museum, next to the Ludwig Mill in Grand Rapids, Ohio. The museum is very interesting. However, when there is land to lay tracks on, ditches full of water are dumb—especially when sides of the canal erode just from towing the canal boats through. This is why we don’t use canals; we use roads and railroads.

Along US 24 the old Wabash & Erie Canal towpath is now a road. This is a point of personal interest because my aunt and uncle, Ila and Dale Dick, owned and operated a semi which was equipped with a heavy truck axle designed by my dad Wes and his team—Dana Corporation’s first—in the 1970s. Their truck is plotted too. You can see it takes about four times as much power to haul cargo by road at roughly the same speed as a train. Therefore it takes that much more energy to get the cargo from here to there compared to trains and boats. But trucks are more flexible than trains, since you can send them everywhere that roads go; and that’s why we use trucks to get it there: It may cost more per mile, but we can get it there by a more direct route.

Then of course there are cargo airplanes. They aren’t cheap; you’ll need roughly 2.5 to 5 times the energy to get it there compared to a truck, and roughly 10 to 20 times the energy if you used a container ship or train; but you can get it there about 10 times faster than trucks and trains and over 20 times faster than a container ship. So if it’s a really important last-minute package or if you want something like a fresh pineapple from Hawaii, it can be worth it.

Finally we have airships. There are classical airships like the Hindenburg and it’s little brothers that came before it; and there are the "new" so-called "hybrid airships". Both types aren’t much faster than trucks or trains; and both are dreadfully slow compared to the usual way of getting it there by air, traveling at roughly a fifth the speed of a cargo jet. And in terms of energy cost, large classical airships like the ones that flew in the 1930s are just barely cheaper than the most efficient cargo planes; meanwhile very large "hybrid" airships—using performance numbers published by their proponents, mind you—aren’t any cheaper than a 747, let alone as cheap as the old-school airships. And again, in terms of energy, trains, trucks, and cargo ships are a whole lot cheaper.

At the risk of pointing out what you may already have noticed, isn’t it fascinating that the proposed (yet never yet built, let alone put into service) high-tech, "hybrid" airships aren’t much faster than real airships that flew in the 1920s and 1930s? And isn’t it strange that the old-style airships are also a much cheaper way to get it there compared to these new-fangled contraptions?

But they aren’t new-fangled at all as it turns out. The 1977 World Book Encyclopedia Science Year Annual, on pages 190 through 199, proudly announced "Airships Make a Comeback". Among the ideas touted then and years before as part of our then soon-to-be then future—and mind you, this is going on forty years ago—were such things as these: The "Helium Horse" cargo transport airship. "Deltoid" and flying saucer shaped airships. Airships with four helicopters slung underneath (which ended in the Piasecki Helistat disaster). Airships for transporting gaseous natural gas (can you say Hindenburg?). Airships powered by three megawatt nuclear reactors (now can you say Hindenburg?). And even a "hybrid in an ellipsoidal shape, which is like a slightly elongated football with rounded ends," proclaimed as the latest and greatest from Boeing—a poor description at best of doing what is yet again being re-hashed all over again today.

Of course, there are also the usual arguments put forth by the proponents of airships for transportation: "This would eliminate building roads" or "you can’t build roads to there." Sure, there are places where roads are impassable part of the year; so we do our hauling during the seasons when they are. And roads can be built just about anywhere, despite it being said that they would be too hard to build; hence, the Al-Can Highway.

During my lifetime I’ve seen, "up close and personal," roughly five billion in today’s dollars spent chasing airships for transportation. Five billion dollars can build a lot of road and lay a lot of track; meanwhile, the only tangible evidence of these airship projects is a vast mountain of useless paperwork—most of which ended up in local landfills, only to be recycled in the figurative sense of the word.

The "airship renaissance" has always been just around the corner ever since the end of World War II. There has always been an impending "helium overcast", with a sky so crowded with blimps that it would blot out the sun. But the only real product—if one can call it that—has been employment: employment of a bunch of engineers that just don’t get the simple, basic, and straight-forward engineering science so eloquently put forth by von Kármán in What Price Speed?

Theodore von Kármán was the first to note that there is an effective realistic limit to how fast you can go for how cheap you want to get it there, by applying rational thought and analysis any and all forms of transport—hence the von Kármán-Gabrielli limit that is, in practice, only exceeded by the efficiency of hard steel wheels rolling on hard steel rails. What would von Kármán think of his eloquent and insightful message falling on the deaf minds of today?

At the circus, the best acts get the center ring. Those who are in the know understand that airships as part of our transportation infrastructure are an old act, relegated to the side show for very good reasons.

Therefore I feel sorry for investors and shareholders that are enticed away from the center ring, spending it all on the hucksters; but only as sorry as one feel for one who’s been duped and swindled.

As the Romans used to say, "Caveat Emptor."

Joseph DickAbout the author: Joseph A. Dick is an independent design and systems engineering consultant and an aerospace and automotive systems expert for Robson Forensic, Inc. (http://www.robsonforensic.com/)

The views expressed are those of the author and are not necessarily those of Scientific American.






Comments 52 Comments

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  1. 1. J. A. Dick 6:30 pm 05/30/2011

    jbay, in metric, as I mentioned much earlier, you have to use weight, not mass. with metric units you have to also divide by g (9.81 m/s^2). The "What Price Speed – Revisited" article I provided a link for shows this in the units of the vertical axis: kW/(tonne x g x m/s)

    So 2x2796kW/(12.7tonne x 9.81m/s^2 x 88m/s) = 0.51

    Large helicopters are very inefficient, which is why we use all-wheel-drive trucks, like the WWII "deuce and a half" and its descendants, to get aid to people in remote areas using the same roads they do; if they require 100 tonnes of aid, they usually have roads.

    Link to this
  2. 2. J. A. Dick 6:33 pm 05/30/2011

    Well, HowardB, you are of course entitled to your opinion. Many readers have, however, contacted me privately to thank me for taking the time to explain things thoroughly.

    Link to this
  3. 3. J. A. Dick 6:34 pm 05/30/2011

    jbay, I see you got the 9.81 – as you can see I’m doing some catching up… : )

    Link to this
  4. 4. J. A. Dick 7:22 pm 05/30/2011

    I used Jane’s, which is corroborated by internal Goodyear-Zeppelin data. I’m curious what your source is.

    A lesser-known fact about the NT is that it was the NT-07, and was supposed to haul 12 passengers. Zeppelin was overly optimistic on the weight savings offered by their "new technology"; as a result, they had to add a cylindrical section to the original design. They quickly dropped the -07 part of the designation, since they didn’t want that bit known. Based on the original designation scheme, it would now be known as the NT-08.255. Hence the ugly shape.

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  5. 5. davblo 8:29 pm 05/30/2011

    "…your arguments are an incoherent jumble…"

    Actually I thought they were very simple. I merely questioned the use of Speed on both axes and commented on the effect of such a graph and later gave a clear example.

    I apologise if I come across as rude, but that was born of frustration from lack of direct answers.

    After a days further thought I think I can answer my own questions.

    Concerning transport of goods from A to B, the values on the vertical axis of the graph are Power/(Payload * Speed).

    Now Power is the "rate of use" of energy so tells us nothing of the overall energy cost of the journey. The total energy cost for the journey will be the Power * Time.

    Time is of course Distance/Speed, so total energy cost is Power * (Distance/Speed).

    If we are interested in total Energy cost per unit Distance, then that will be just Power/Speed.

    Furthermore, if we are interested in Energy cost per unit Distance per unit Payload, then that will be Power/(Speed*Payload); which is just what is plotted on the vertical axis.

    (With payload in Kg I find the above to have units of m/s^2; so I guess you throw in a "g" factor turning Payload from mass to a force to get a dimensionless result; but that doesn’t have much affect since "g" is a constant).

    Anyway, the vertical axis is none other than Energy cost to transport unit Payload over unit Distance.

    On that axis, ships, trains and trucks use much less Energy (per unit Payload per unit Distance) than aeroplanes and airships.

    So for low cost – use ships, trains and trucks.

    The horizontal axis is actually purely arbitrary, and in this case relates to an interest in Speed of transportation. One could equally well plot any other parameter of interest, "X", here with a view to seeing – all other things being equal (Energy cost per unit Payload per unit Distance)which option gives me best(or worst) value for "X".

    So plotting Speed on the horizontal axis shows that if you are willing to pay higher cost (Energy per unit Payload per unit Distance), then you can get an airship but it won’t give you much extra Speed; whereas for the same extra cost you can use an aeroplane and get a lot more (more than 5 times) Speed.

    So it wasn’t that hard. It didn’t need an complicated Physics; just a clear explanation.

    I don’t know whether you can follow my explanation; but I now agree with your conclusions.

    /davblo

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  6. 6. davblo 8:48 pm 05/30/2011

    One ought to really make a list of other possible factors of interest, "X", and possibly plot them on the horizontal axis to see – for equivalent Energy cost per unit Payload per unit Distance, which option gives me best "X"?

    I haven’t had time to think much on this, but off the top of my head..

    1. For passenger travel – comfort and space; compare sitting packed like sardine to being able to get up and walk around.

    2. For freight – reliability and continuity of continuous supply, pipeline style; items always departing and always arriving; time of transit irrelevant.

    3. Cost of infrastructure

    4. Environmental protection vs. damage

    5… (any more suggestions?)

    /davblo

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  7. 7. jbay 8:51 pm 05/30/2011

    I agree that helicopters are inefficient. But, they still have a role in today’s transportation infrastructure. Nobody uses them for long-range shipping of course (if they can avoid it), because it’s not their niche. But they’re nonetheless still used – such as I pointed out earlier, to reach places inaccessible by roads like the arctic. If Concordes are not used anymore despite their high score, and helicopters are used so frequently today, despite their appalling inefficiency (both by Von Karman’s measure and by the measure of J/kg-m), then it stands to reason that airships might have a future. That’s basically my thesis, and all I really mean to point out.

    I appreciate the fast replies, by the way. =) By the end of the week you’ll probably have had to write more words answering our squabbles than for the original article!

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  8. 8. rogerdodger 4:55 am 05/31/2011

    Joseph – phew! You seem to have stirred a lot of controversy on what I would have thought was an innocent subject that could be addressed in a rational and temperate way. I enjoyed your article and thank you for it.

    I am a non-scientist (geographer by training – many years ago) and would like to raise an issue none of your many correspondents seem to have touched on. I remember being told by a much-respected geography professor that "the most efficient form of transport is a flow". He never addressed the science of that in the terms you have but in my youthful innocence it seemed to make sense. You feed something into a pipeline (literal or metaphorical) and with the aid of some energy (unless the flow is entirely downhill) you move it continuously to its destination without any interruption. That avoids the cost of something you understandably don’t deal with (it’s an economic argument rather than scientific) – "break of bulk". Every time you stop the efficient flow to transfer the goods or people it adds avoidable cost. That’s why shipping pre-containerisation was so much less efficient than with containers. Getting as close as possible to a flow in any mode of transport maximises efficiency.

    I’d be interested in your comments from scientific viewpoint. Thanks.

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  9. 9. J. A. Dick 6:33 am 05/31/2011

    jbay, you are the only person "here" – oh yes, there are many listeners, I can assure you… :) – to ponder, calculate, question, and then figure out what I apparently so ineffectively said.

    So, I’ve waited for this bit: I was hoping PGracy would look the numbers up for the NT on Wikipedia – apologies to HowardB if that seems rude (and apparently even mentioning that is not PC; but guess what, Science is about facts and not about being "nice", so get over it if your not a member of the "facts rule" club) – have you run the numbers and put them on the von Karman graph for the Zeppelin NT?

    It turns out thus: 3x150kW/(1.129tonne x 9.81m/s^2 x 31m/s) = 1.3

    Yes, it’s a small airship. Yes, there are scale factors involved. I leave it you you to make the comparison based on von Karman’s measure of what is efficient, and what is not.

    As a very good friend commented, "Just ask them to show you where you’re wrong." That’s a great suggestion; but I actually have to pass the buck, because I can’t – despite my lifelong love of airships and balloons – prove von Karman wrong.

    If you can, I would be ever so grateful.

    Meanwhile, don’t shoot the messenger: The message comes from the laws of physics, the rules of mathematics, the tenants of economics, and so on.

    Link to this
  10. 10. J. A. Dick 7:05 am 05/31/2011

    Welcome, davblo.

    All good things to think about.

    When I was studying under Prof. F. J. Marshall at Purdue, he had a marvellously complex computer program that managed to capture the design of a jet transport in 27 computational variables. If you think its hard to walk around in your own home when the lights go out, think about being in unfamiliar territory without the lights ever being on!

    Fortunately, Prof. Marshall started out "easy" – in ‘his’ opinion, according to his students. Just two of the 27 variables: Wing span vs. wing chord; how do you optimise that? After playing blindly in computer space (mind you, this was in the days of typing things onto Hollerith cards, standing in line, and after they were run standing in line at the line printer for results), only then did Prof. Marshall point to data available in books on tests and theory and research that would have eliminated the much-less-optimum solutions.

    Then he upped the ante: Can the wing hold the weight? Back to the trial and error, or the calculations, or the research… Then he threw in stability, compressibility, and a raft of other factors… Before anyone knew it, there were 27 variables to consider!

    At the risk of sounding self-important – and mind you, I wouldn’t have thought of it if you hadn’t responded with good questions – I was the rat bastard that did the Kobayashi Maru bit by seeing if Prof. Marshall’s solution validation program might be useful in refining a solution.

    Lo and behold, it was. When asked, "How are you getting such fantastic results?", I openly and honestly responded that I guessed that the validation program might be based on the same algorithms contained in CADAC ("Computer Aided Design of Air Craft), and that I had indeed made a gradual transition from using CADAC to the program we used to validate our computations.

    Again, I would remind you, that this was all in the days of Hollerith cards, and that a significant amount of extra effort (and expense, given that I had to pay for some of the extra computational runs) was required to achieve this.

    Link to this
  11. 11. J. A. Dick 7:14 am 05/31/2011

    My point in relating all this is that we all have to dig deep and check, check, and recheck the computations.

    At the same time, von Karman loved to tell the tale of the professor, while transcribing his notes to the chalkboard, said, "I don’t know if this symbol is a 2 or a Z, but the equation is correct."

    This Q&A aspect of the Guest Blog is of course aimed at, of Q&A. As a fan of Christopher Hitchens, who is a fan in turn of Thomas Jefferson, I hereby quote Jefferson thus:

    "Fix reason firmly in her seat, and call to her tribunal every fact, every opinion. Question with boldness even the existence of a God; because, if there is one, he must more approve of the homage of reason, than that of blindfolded fear."

    I, for one, have invested a lifetime in understanding the engineering and technologies required to build and operate airships.

    As a result, I am unafraid of the questions, and I am unafraid of the answers.

    Where do you stand?

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  12. 12. J. A. Dick 7:59 am 05/31/2011

    rogerdodger,

    Whew, indeed. I was just trying to pass on a few ideas for discussion, and all the sudden, "Whoomp! There it is!" – which rode in on the coattails of Kano in the same way that Kid Rock put "All Summer Long" on top of Warren Zevon’s "Werewolves of London"; but I digress, and show off at the same time.

    To that end, I must say, if one isn’t going to blow one’s own horn, who will? And if I was all about modesty, I wouldn’t have bothered to offer what I’ve learned for the consideration of others to contemplate.

    I appreciate your comments, especially since the point of Scientific American is to bring "The World’s Progress" to its readership.

    I too had teachers that impressed upon me that communities happen near arteries (interesting multiple use of the word, that); and that the size of communities is organic, depending on such factors that they surround two rivers that join, that they are where a river joins a lake, and so on.

    In terms of your request for my "comments from a scientific viewpoint" on the subject of flow, I suggest reading Eliahu Goldratt’s "The Goal" (http://en.wikipedia.org/wiki/The_Goal_%28novel%29), in which he eloquently points out some aspects of flow which may interest you.

    Additionally, the work of Genich Taguchi might also interest you. He addresses the concept of quality in terms of "loss to the customer" as opposed to doing a thing in the way that suits the manufacturer. (My favourite example from Taguchi is the concept of shirts, and their collar sizes and sleeve lengths; a company may offer dress shirts made of fine cloth assembled with impeccable stitching, but if their collar sizes and sleeve lengths don’t include your intermediate needs, then they don’t produce a product with the qualities you need, and hence they don’t produce a _quality_ product.)

    So, rogerdodger, to be scientific about your request for my scientific "point of view":

    Science is about independently verifiable facts; thus viewpoints need not apply. Science is a method through which we discern, to the best of our ability with the tools at our disposal, what is measurable; and, per Galileo, we should always, "Measure that which can be measured, and make measurable that which we cannot."

    In short – though it will require 50 or so minutes of your time if you only watch it once – my scientific viewpoint is that of Jacob Bronowski, in the 11th episode of "The Ascent of Man":"Knowledge and Certainty": http://video.google.com/videoplay?docid=-8703061764104921754#

    Thanks ever so much for your interest,

    J.A.Dick

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  13. 13. npewaa 1:02 pm 05/31/2011

    For jbay
    In today’s “financial based” industrial formula the costs of all aspects of operation are important. That includes the number of airships required to replace existing carriage methods. What weather conditions can I fly in or other limitations do weather or winds impart on airships? What flight ways would be necessary to address weather issues? Where would the loading and unloading facilities be located?
    A rail engineer would have to address fuel burn issues but I believe for cross continental transport the pound / dollar cost is the best.
    Here’s an example that I believe is simple and straight forward.
    If I have freight train with 500 loaded cars with each freight container at 40K pounds.
    An airship the size of the Hindenberg (800 ft long) might be able to carry 160K (weight of a M-1 Abrams) which would mean you would need 125 airships each carrying four containers to replace that train.
    Since today’s economies are “just in time” the delivery of the freight is time critical, even given the similar speeds, the established transportation industry gives the tilt to rail. Even with the flexibility an airship would have from deviating or straight-lining its course to a destination a new infrastructure would be necessary to support the airship.
    A 800 ft long floating / minimally powered airfoil would have fun maneuvering in a wind. Since most winds travel west to east the efficiency would favor west to east transport.
    Whether it is with recycling Helium for internal carriage or on-ground replenishment there is a significant infrastructure issue.
    Container ships now carry 8K containers on a single delivery with over 50% of them a long distance from its final destination. You would need 1,000 airships per boat.
    With today’s corporate leadership any airship program attempted by the defense establishments would end up being cost prohibitive and very late in delivery. Look how Lockheed screwed up the F-22 and its successor the F-35. Or even their airship attempts have eaten budgets and slipped schedules.
    Look at Boeing with the 787 and more use of the Jack Welch mantra. 3+ years late and cost is 2+ times the original estimate.
    What would power the airships used in freight transport?
    So where is the efficiency? Who on Wall Street would support this type of one direction product flow (west to east)?
    Where would you find a small company with the capabilities to pull off this type of effort?

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  14. 14. andrewf 4:13 pm 05/31/2011

    Please plot helicopters on your nifty chart there. I imagine they’ll be in the same vicinity as airships. Then kindly explain why helicopters are used extensively, but it would be absurd for airships to find any role in transportation.

    Airships are for niche markets, especially for lifting heavy loads to isolated areas, like building a mine. An airship can carry huge pieces of mining equipment that could not be carried on a truck. In urban areas, they could conceivably be used to move large loads that do not fit on streets (amid lightposts and power lines). In Toronto recently, it took a team of dozens of people several days to move beer vats from a port to a commercial brewery on truck, causing considerable disruption.

    I don’t think anyone expects them to form a backbone of cargo transport like trains, trucks or container ships, but to write them off completely when they are competing with things like heavy lift helicopters is rather short-sighted.

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  15. 15. PGracey 4:52 pm 05/31/2011

    I did not have access to Janes so as you surmise I used Wikipedia and followed links to a Navy site for a bit of confirmation. One though about the nature if this discussion so far is that it is mostly about bulk cargo efficiency and is in most cases directed to point A to point B travel.
    I agree that the NT is too small to make much of a difference to the aims of the old giants. It even has to be carried across oceans rather than flown the distance, and yet it can do the trip from San Jose to Long Beach in about eight hours using one engine. My Prius just did the same trip in about the same amount of time counting convenience stops and abysmal traffic. Using the SI units you used for maximum speed and power yields a number of 1.3 but for one engine at cruise speed 20M/s I get a number around 0.67, though if the engine at cruise can be set to 75% power that number goes to .5.

    For passenger service it is quite marginal, but I note that its economics as an advertising medium seem to allow for this added duty.

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  16. 16. J. A. Dick 9:10 pm 05/31/2011

    The values typical of helicopters were discussed above, so you can add them to the plot if you wish. Also, there is a link in my article to "What Price Speed – Revisited" from the Royal Academy of Engineering.

    Helicopters are used extensively because they are small, take off vertically, can be operated by one person, and when you’re done with them, you park them. Conversely, airships are very large, can take off vertically but are lumbering in doing so, need a ground crew to launch and land, and need constant attention to monitor and maintain their pressurization systems and their buoyancy at a mast or even while in a hangar.

    Contrary to your statement regarding mines, airships cannot lift huge pieces of equipment. A Hindenburg-sized airship built with current materials would have a payload of about 70 tons. That’s less than the weight of a fully loaded semi. So, between building and operating an expensive airship over 240 meters long with a large specialized expensive flight crew, or a relatively inexpensive truck with a single driver over a road that you’ll need anyway, the choice is made for us by economics and practicality.

    I can write them off completely because the numbers just don’t make sense to pursue them in the first place. Even the "beer vat" example you give can’t be justified in terms of cost; and no way in Hades do I want something like that flying over my house! Too much can go wrong. Ever see the Piaseki helistat crash? Not over my house, no way.

    That’s why we use roads to get to remote areas, and run trucks on them. That’s why we move over-sized things by road and move a few phone lines and traffic lights if it’s the odd huge thing. Economics, economics, economics, period.

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  17. 17. J. A. Dick 9:39 pm 05/31/2011

    That’s why the NT is a complete failure, and was always destined to be. By complete failure, I mean that they have failed as business proposition.

    To date the Zeppelin NT has been pursued for over 20 years. In that time I think it is safe to say that well over $100 million has been spent. It was reported that it took $34 million to get the first NT designed, built, and certified, and the three NT being purchased by Goodyear are reported to be for $21 million each. (That alone is $97 million.)

    Give the choice of doing that, or buying and operating a couple of 737s, I’d go the 737s every time. Or even better, a fleet of trucks. Either can and does make a profit; Zeppelin NT, ummm, not so much.

    So, after 20 years and huge investment, the NT arrives at its inglorious end: Hauling a banner and a billboard around.

    This is something that American Blimp did immediately by comparison, getting busy doing banner-for-hire back in 1990; they did it for far, far less money, and have been busy doing that and much more during the same 20 years.

    Meanwhile, regarding your trip from San Jose to Long Beach, not only 12, but 15 passengers can fit into a van, and one of them can drive – no need for a specialized pilot. The van costs much less to build, and much less to operate. It only needs a parking spot at the end of the trip, which can be tar, gravel, or even dirt; no three man crew or expensive mooring mast required.

    Therefore your scenario, while quaint, just won’t fly economically, and that’s why we rent a van and drive it ourselves instead of chartering an NT with one engine running.

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  18. 18. andrewf 11:03 pm 05/31/2011

    A fully loaded truck weighs 40 tonnes. Payload is less.

    And for a road to carry that load, it has to be built to a relatively high standard ($$$). Many mines in isolated areas do not have that level of infrastructure in place. Even if they intend to build it (in order to haul out the ore), that takes years, which can delay the development of the mine. I think you might be underestimating the utility of heavy lift VTOL vehicles in remote areas, but then, I imagine you are not an expert in the mining industry, despite your dismissive tone. Beyond that, your claim that $5 billion builds a lot of roads/rails sounds laughably naive. Do we build 100 km of rail through virgin forest at a cost of billions of dollars just to deliver a few loads to a remote location? Global infrastructure spend is in the trillions. $5 billion is a drop in the bucket.

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  19. 19. Dr. Strangelove 6:33 am 06/1/2011

    Airships are ideal for hauling heavy loads to inaccessible places where there are no good roads, no rail, no airport and landlocked. Airships will compete with cargo helicopters. Which is more efficient?

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  20. 20. J. A. Dick 8:14 am 06/1/2011

    Another post from the author…

    Well, I see that things have gone rather quiet. To me, that is a good sign. There is nothing I’d rather see than just a few proper zeppelins in the sky; but I cannot support, and I must decry efforts to do so, when such effort is an utter waste of time and valuable resources.

    Hugo Eckener concluded his 1938 book, "My Zeppelins" (as translated by Douglas Robinson) thus:

    "Let us continue our self-contemplation and find therein the resolution and courage to acknowledge freely and openly our belief in such ideals and to demonstrate them practically by our actions in both domestic and foreign policy. Let us live by example in a world devoid of ideals and beliefs which seems to recognise only the policy of naked power."

    Eckener believed that the zeppelin would only arise again when the world was at peace. Therefore wouldn’t it be a better tribute to the wonderment he helped to create if we all spent our time in solving the great problems of our age, instead of ignoring physics and trying to justify the impossible when there are greater problems to be solved in the world?

    J. A. Dick

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  21. 21. J. A. Dick 8:45 pm 06/1/2011

    Airships cannot haul heavy loads unless there is significant infrastructure in place at the destination; at the very least, a very large open space is required set down, and provision is made to re-ballast the airship when the cargo is off loaded.

    Airships are literally a part of the air; what’s more, if you try to move one from side-to-side, you not only have to accelerate the mass of the vehicle, but you also have to accelerate the air surrounding the vehicle. The physics of this is referred to as "apparent mass", and an airship can behave as if it is up to two times as "heavy" as its own mass.

    Conversely, if the air begins to move, it just takes the airship with it, almost as if the airship weighs nothing. While proposals to use engines to keep and airship in place without a mooring mast are interesting exercises in calculation, in practice you’d pretty much need a near dead calm for hours on end in order to offload any significant quantity of cargo – so you still need a mooring mast in practice.

    If the land is flat enough and clear enough to permit landing, it’s probably flat enough to drive over in an M35 or an M939 6×6 truck. After a few trips, you end up with a path. If you make enough trips, you maybe bring in some gravel, then tar, and pretty soon there’s a small town at the end of that road doing whatever it was that you were going there for; so the road gets bigger, and the town gets bigger, and so on.

    Finally, it isn’t which is more efficient, it’s which is more _economical_ between airships and helicopters. Economics is the ultimate measure of efficiency, since money is essentially energy made exchangeable.

    Helicopters are cheaper, smaller, don’t need big ground crews to land, can land just about anywhere, and you can just park them and forget them when you’re not using them. That’s why we use ‘em.

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  22. 22. J. A. Dick 9:11 pm 06/1/2011

    You take my $5 billion builds a lot of road out of context to argue your point; my point was and remains that $5 billion builds a lot of road that can serve a real purpose, whereas $5 billion spent on airship follies and paper studies is a complete waste. Apparently that point was entirely lost on you, or you choose not to get it in order to try to skewer your "opponent" – which I assure you isn’t me; I’m just the messenger, so don’t shoot!

    Semis can and do drive on no road at all and work perfectly fine without the "$$$" and "built to a high standard" pseudo-requirements you posit. Semis regularly drive down dirt and other unimproved roads, delivering and retrieving cargo in areas remote from pavement and highways. And of course, you certainly must have heard of ice roads.

    If there is something out in the "virgin forest" worth going to get, you can afford to build a rail line. This has been done time and time again throughout history; consider all the narrow-gauge rail lines here in the US that now serve as tourist attractions, which were built to take equipment into and natural resources out of remote areas.

    Now, if you had read any of the posts preceding yours, you wouldn’t make me repeat myself – but fortunately I don’t have to on part of it: Please go to posts 81 and 86 and consider the points made by their authors.

    I’m sorry to be the bearer of what you consider to be "bad news", but airships for cargo in any form will never happen – and it would have already if it was workable, since there really isn’t anything new under the sun; it’s all been done before, been measured, and found wanting.

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  23. 23. Dr. Strangelove 10:24 pm 06/1/2011

    I guess the original appeal of airships in the 1930s is as a luxury airliner, pretty much like the luxury cruise ships. Can you build a big airship that’s like a flying hotel? There’s an appeal to flying at low speed, low altitude, with fantastic view.

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  24. 24. Daniel35 12:11 am 06/2/2011

    But then there’s also Hydrogen. How about covering at least one side of the balloon with some modern light kind of solar cells, to make H2 from water vapor to replace what leaks and to power a solar/H2 hybrid engine to run the prop? There might be a small problem of condensing the water first.

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  25. 25. J. A. Dick 2:01 am 06/2/2011

    You certainly could. Most often the only problem is that everyone wants to reinvent the wheel instead of doing what’s known to work.

    The best thing to do would be to start small, copying the LZ-120 "Bodensee" and use it for dinner cruises; then with that experience, move on to larger airships capable of weekend or week-long cruises.

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  26. 26. J. A. Dick 2:10 am 06/2/2011

    Hydrogen is terribly, terribly dangerous stuff. And it’s illegal to use in airships for that reason.

    Solar panels don’t make enough energy to replace themselves and make an additional copy before they wear out; otherwise, solar panel manufacturers would take themselves off the grid and use their own product to power production. Therefore they’re not cost effective except in extreme applications like powering satellites, or running parking meters where the cost of digging up the sidewalk and running power to them would cost more.

    Sure, the military has been working on autonomous airships with solar panels and batteries for long endurance surveillance; but a the end of the day, simple airplane-type drones can do the same thing and aren’t, as Jay Leno joked, "It’s good to know we’re spending this much on security that can be brought down with a bow and arrow." Yes, it’s not quite that simple of course, but it’s much harder to hit a tiny drone than to rupture a huge flimsy gasbag.

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  27. 27. kebil 5:25 pm 06/4/2011

    Davblo

    The difference between your two examples is invalid. The relationship between payload and power is linear. Generally, doubling the payload, all other factors being equal, requires twice the power. The relationship between speed and friction is squared, doubling the speed quadruples the friction, meaning that four times as much power, nothing else being changed, is needed. So if you can increase the efficiency so that twice the payload can be carried with the same power, you have doubled efficiency. But if you have doubled the speed without needing more power, you have quadrupled your efficiency, hence, doubling the speed should appear more attractive.

    Your welcome for explaining the obvious.

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  28. 28. J. A. Dick 12:46 am 06/5/2011

    kebil,

    Thanks for taking the time to address those points.

    As a point of general interest, readers may find this interesting: http://www.nap.edu/html/biomems/tvonkarman.pdf

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  29. 29. skyship007 8:26 am 06/6/2011

    Hi All,
    Joe is correct that 5 billion has been wasted since the US Navy stopped using blimps in the 60′s. Serious airship development is indeed a waste of time, which is why the US Army and DoD are now funding the LEMV program, which will see the first of three HAV 304′s flying later this year. The HAV stands for hybrid air vehicle and they are designed and built by Hybrid Air Vehicles Ltd from Cranfield in Blighty. Northrop Grumman are providing the surveillance and remote control systems as the 304 is an RPV when on station and only uses a flight crew for transit flights. That makes the 6 week duration mission at 20,000 ft more practical.
    The real interesting part about the LEMV is that it is very similar to the HAV 266 which will follow on as a very fuel efficient long range point to point cargo or passenger aircraft, in addition to medium range heavy lift capabilities.
    The experts in the US DoD as well as the team at Northrop Grumman & Hybrid Air Vehicles all know developing airships is a waste of time, but the HAV is only partly based on blimp technology, as it has a very different lifting body shape, vectored thrust from the 4 diesel engines and twin hoverskirts for off airport operations. It does not even need a mast at the landing site.
    I think the nay sayers are in for a big surprise later this year, just like when they first saw Concord, the Harrier jump jet or a large hovercraft. When it comes to new ideas in aviation Roger Munks design team at HAV with their nealy 30 years designing useful blimps have finally produced a real fuel efficient game changer, even if I admit the diesels are German and the envelope is from the USA.
    Regards JB (Airship & Blimp Consultant http://www.hybridairship.net)

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  30. 30. Hochstetlerr 2:08 pm 06/6/2011

    My good friend Joe, you make excellent observations about the drag issue that the hybrids and then use these facts (specific to hybrids) to dump ALL airship concepts of the past or possible future into the dustbin of history. Your article stumbles into the fallacy of comparing transport airships (hybrid or conventional) with all other transport systems, without factoring in the hidden but exorbitant costs of the extensive ground infrastructure that enable each of those legacy transport systems to function. Maybe you’re unaware of the inordinate efforts necessary to transport any appreciable amount of equipment or supplies by ground vehicle or conventional aircraft in those areas north of the 40th parallel. Those of us who have been to the Canadian North West Territories know just how growth constrained the Canadian economy is simply because the quantity of fuel and materials needed to effectively extract their oil, gas, and mineral riches can’t all be supplied during the short seasons when the ice roads are passable. You mention the Al-Can Highway as a prime example of the “just build a road” solution, but did you know its construction actually cost over $1,825,000,000 (in 2010 dollars). Those 1,422 miles of road cost more than $1,283,000 (2010 dollars) per mile. As to expanding the conventional jet aviation infrastructure, except for countries where the government can bulldoze new airports into existence, the average time it takes simply to add a new runway at a large airport is greater than the time it took to build the great pyramid of Cheops. The rational for the cargo airship in the 21st Century is not to compete with the existing transport infrastructure which, by any measure, (legal, economic, or environmental) is essentially locked in to its current "mature" status in all the developed nations. It’s only the transport airship that is able to provide the yet to be developed places of the world with an affordable transportation system that is not dependant on extensive, expensive, and vulnerable ground infrastructures.  Aviation history is filled with examples where some of the visionaries gave up too soon. The light went out for them, and they became bitter apostates of what they once believed in so heartily. Don’t let that light go out for you Joe.

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  31. 31. skyship007 11:35 am 06/7/2011

    Hi All,
    The big error in this article is to try and compare a normal cargo aircraft with a hybrid air vehicle, the normal fixed wing aircraft needs airports at both ends of the route, but the new HAV’s do not as they use hoverskirts for undercart. The comparison should be with a heavy lift helicopter like the Mil 26 which is powered by two 12,000 shp turbines and has the same 20 tonne payload as the HAV 266. The HAV has four 600 hp diesels and it uses a fraction of the fuel of any heavy lift helicopter. At present the new generation of hybrid air vehicles are only intended for long endurance surveillance, heavy lift and long range point to point cargo or passengers and they are way ahead in fuel economy terms, not that there is another way of doing long range off airport operations anyway, which is why the US military are funding the LEMV program.
    Regards JB (Airship & Blimp Consultant)

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  32. 32. J. A. Dick 12:03 pm 06/7/2011

    With all due respect, R, the laws of physics are the ultimate arbiter of what can be done; and when combined with economics, which are ultimately the level playing field of energy being made exchangeable, airships are, as Director Colman at Zeppelin said, "ein Sackgasse am Himmel" – a cul-du-sac in heaven.

    Argue as you might, and wish as you will, it would have an ongoing enterprise if there was money in it.

    I wouldn’t have poked my head back into the silly useless efforts of those who have been breathing too much helium – thus depriving themselves oxygen figuratively, if not literally – had I not been asked by a client to review the work of a hybrid airship "manufacturer" associated with a major military industrial supplier. I stated what physics allow, and what in 1927 Charles P. Burgess recognised as absolute, independently verifiable truth in Chapter X (see link in my article): Below a certain speed, putting wings on a blimp makes no sense; and conversely, putting a gasbag on an airplane is equally nonsensical.

    For my non-conpensated expert opinion on behalf of a client who simply wanted to know my opinion on the matter, I was confronted with promotional opinions and a veritable shouting-down for espousing a "flat-earth" opinion – quite literally.

    I brought to the attention of the promoting "experts" that water recovery actually worked so well that condensers were removed from the Macon, and that the "flat-earth" metaphor used to denounce Burgess and his "Jewish physics" in what was supposedly a professional engineering discussion, was in fact a myth created by Washington Irving to make his "biography" of Columbus saleable – hence the ancient "hull up/hull down" of ancient mariners in describing the effect of the curvature of the Earth as a ship departed port, let alone Eratosthenes damned accurate measure of the circumference of the Earth in 276 BC…

    Well, the end result was that my client was contacted angrily with what could easily be construed as an attempt to get me fired; and while I have been repeatedly assured that this event in no way affected my business relationship with my client – and I even have this in writing – said client chose to employ another individual pursuant to programming equipment for quality assurance test data acquisition – despite my almost four year relationship with that client, and my experience over the last 30 years in laboratory and vehicle instrumentation and test.

    Funny how corporate initiative and ill-conceived passion can impact one’s own simple efforts to stay employed!

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  33. 33. J. A. Dick 12:37 pm 06/7/2011

    Oh, for heaven’s sake! There is nothing but cargo transport. Treat it as a black box, and look at the economics. Have you ever heard of a double-blind experiment? Such is required when the Heisenberg-aspects of psychology are involved. Go to a drive-off of vehicles with any manufacturer – be it Ford, Toyota, Mercedes – and the minions always tell the big cheese what he wants to hear.

    Michael Crichton, an MD I unfortunately feel the need to point out, pointed out in his novel "State of Fear" that the double-blind must be a requisite for research when emotion can come into play. Physics and engineering are supposed to be above that sort of malarkey.

    Therefore, JB, just as I said to davblo: If you have something to say, get busy and write a scholarly article which refutes the work of Theodor von Karman and Gabrielli in their American Society of Mechanical Engineer’s article in 1950, along with refuting the findings of Yong, Smith, Hatano and Hillmansen as published by the Royal Academy of Engineering.

    But physics is physics, and, per John Adams, facts are stubborn things. I wonder if John Adams would back me up on my hypothesis that the world would be a better place given the following: Criminal intent and criminal negligence are punishable under the law; meanwhile fraud is only classified as an "intentional" crime. What if there were such a thing as fraud by neglect? If so, could one bring suit based on ignoring the laws of physics? Or should we simply rely on "Caveat Emptor" as our basis for protecting the rights of the investor? A well-educated proletariat is the foundation of any free-thinking and free-speaking society, and the opponent of the intellectual-bourgeoisie; therefore I leave it to the individual reader to decide for themselves: Do any of your arguments hold water?

    Airships are huge, haul very little for their size, and require tracts of land far larger than their size just to park while unattended; airplanes haul a lot and can be parked like cars in a parking lot.

    Comparing airships to helicopters is a "straw man" – a purposeful misrepresentation of my position, by definition: Helicopters are not currently part of our transportation infrastructure, and they never will be – just like airships are not, and never will be part of our future infrastructure.

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  34. 34. J. A. Dick 12:47 pm 06/7/2011

    By the way, JB, if you agree that my ever-so-rough estimate of US$5billion as applicable to reality, I can’t for the life of me see how you can reconcile that my estimate includes all the current wasteful government expenditures chasing this antique and useless technology.

    If you want persistent observation over some territorial boundary, why not send up a fixed-wing UAV; and then another just before you need to recall the first one for refuelling, and so on.

    As Jay Leno pointed out, why use something for military purposes than can be, in effect, brought down with a bow and arrow? Save the zeppelins for the antique car shows. Maybe Jay might want one just to show off; but other than that, please! Give the helium hokum a rest!

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  35. 35. Philbr 10:20 pm 06/7/2011

    I found your article a very interesting read. I however do have a question on the premise of your findings and on the idea that airships will never be a viable option for tranportation.

    As far as I understand it your measurements are based on feasibly of technologies running on fossil fuel. I am currently unaware of any method of effectively producing jet fuel artifically in a cost effective manner.

    So my question is if peak oil does hit us in the near future what do you forsee as our air transport options?

    There arent really any valid options to replace jet engines if the fuel becomes too expensive and Eletric options dont scale well I understand. As a result wouldnt current alternative engine technology apply better to Airships?

    How does the transportation methods your comparing hold up to a change in power source?

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  36. 36. J. A. Dick 11:31 pm 06/7/2011

    Interesting questions and comments, Philbr. For one, I’m not sure I even buy into the whole "peak oil" thing – and let me qualify that by saying I certainly don’t buy into the scaremongering sort of non-think that seems to perceive that we’ll just suddenly run out of the stuff someone just turned off the valve. After all, shale oil is a perfectly viable source from which liquid fuels can be made – and please don’t go into the environmental tangent; that’s a separate discussion.

    There are other ways of making liquid fuels as well, and I’m sure we’ll continue to find resources of energy that will take the form of liquids and be usable in engines of all sorts.

    To date, there are no viable "alternative" power sources for aircraft. Solar panels in general don’t create enough power to make copies of themselves, which is why solar panel manufacturers still not off the grid; anyway, that’s not really a viable way to power an aircraft meant to transport anything. There are all manner of unworkable proposals out there, which I’d be more than happy to comment on at length and probably will do so in another article in the near future.

    But short story long, as I like to say, the paradigm is not fossil fuels, but liquid fuels; and that paradigm is very unlikely to change.

    Here’s a thing to think on: Hydrogen is often touted as the energy source of the future; yet there is no "source" of hydrogen, we have to make it using other energy sources, and hydrogen in its pure form is bloody dangerous and difficult to contain. Meanwhile, consider this: We’re already using hydrogen as fuel, by using long carbon chains as tiny "containers" that mass together in the form of a liquid. Pretty neat way of looking at the world, eh? At least I think so.

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  37. 37. Philbr 12:28 am 06/8/2011

    Thankyou for your reply.

    Although I cant make a judgement on when available and easily accessable oil as a fuel source would run out, it seems likely that in the future it will as resources like it are in the end of a finite quantity. As I understand the peak oil arguement it is not so much an issue of running out of oil as the production of oil as a feul source growing in expense to the point where it becomes unviable economicly. While it may be a while before this happens it seems likely to be an enevitable situation eventually.

    I bring this up in relation to your statement about airships never being a feasible option for future freight. As I understand it an airship can use current Electric engine technology to provide propulsion and this capacity is quite scalable since life is provided by the lifting gas. However the same technology cannot be easily applied to large cargo sized plane.

    Now taking into account biofuels and such, Jet engines still require quite high energy dense fuel sources to run. My understanding of it is manufacturing such fuels is more difficult, energy intense and costly.

    I guess my argument is that it seems likely that while an Airship would be less efficent purely on a energy use level, it may become economicly viable as a transportation method because it can be powered using cheaper, more available fuel sources.

    On hydrogen, I have always really only seen it as a energy storage system rather than a source.

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  38. 38. J. A. Dick 7:26 am 06/8/2011

    Mr. Hochstetlerr,

    I find it difficult to understand that you permit yourself to address me as "my good friend", except in the context of why I wrote my article. You don’t know me. Yes, you met me once or thrice; but the only reason I address you here, in this venue, only underlines how sad the state of education remains with regard to basic scientific principles that any high school student should readily apprehend.

    I have never wavered in my love of antiques. For instance, Duesenbergs are fantastic pieces of machinery: They were the first SUVs – albeit only two wheel drive – in an era when the Indianpolis 500 was all about getting a car to actually go 500 miles all in one go, and when roads were all but non-existent.

    The Indianapolis 500 continued to work its magic until Andy Granatelli raced his turbine-powered all-wheel-drive car in 1968, foiled by the failure of a single tooth of one gear in the transmission, well in the lead, and only ten laps short of finishing. If any one event heralded the death of automotive engineering in the US, it was the subsequent "outlawing" of all-wheel drive and turbine engines by the race commission at Indy.

    Few people know that Indiana had no less than 80 automobile manufacturing companies – let alone that the first Indy 500 was won by the "Marmon Wasp", raced alone by its driver, Ray Harroun, making 500 miles in 6 hours, 42 minutes, and 8 seconds, and without a "mechanic" with because the Marmon Wasp had – wait for it… – a rear view mirror. What a transition from 1911 to 1968, when a race dedicated to the advancement of automobile technology could suffer such de-evolution? From creating the single most life-saving appliance known to the motoring public, to denying further development technology.

    Wheels can do one thing besides roll; they can provide friction. That friction can be delivered front-to-back (as in accelerating or braking), or, of equal importance, they can provide the side-to-side ability of traction that keeps a car on the road while cornering.

    When a wheel is driven or is braking in combination with cornering, there is a limit called the "traction circle". (This is just Stevinus’ (1548-1620) law of vector addition.) The point is that if you use a wheel to drive and corner at the same time, you can only do so much of each.

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  39. 39. J. A. Dick 7:52 am 06/8/2011

    Granatelli knew this, and fielded his all wheel drive cars, lapping the competition – and subsequently got "outlawed" under the pretence of unfair competition.

    But what was the point of the Indy 500? To develop cars that could perform – ostensibly for the betterment of the motoring public.

    If you have a rear wheel drive car, the wheels that slip by driving the vehicle aren’t the ones you steer with; the rear wheels slip, and one’s natural tendency is to back off the throttle while using the steering wheels at the front to continue controlling the vehicle.

    If you have a front wheel drive car, the wheels that slip by driving the vehicle are the same ones you steer with; and when that slip happens, all control is lost. A savvy driver (as if any savvy driver would buy, let alone rent a front wheel drive vehicle) will kick the clutch pedal to the floor or put an automatic transmission in neutral in the vague hope that the steering wheels will re-track and allow the driver to regain control of the vehicle.

    Granatelli in 1968 was smart enough to employ all the wheels for driving – just as Zachow and Besserlich had done in 1906: "Who ever heard of a mule walking on two legs?" was their motto.

    By driving all four wheels, less of the traction circle of each tire was consumed by driving, and more was available for cornering; and were it not for the "commission" in charge of Indy, all cars would be safer, and no car would employ the ridiculously unsafe practice of front-wheel-drive.

    How many lives have been lost because of this specific bit of stupidity? How many front-wheel-drive cars have flown off the road because traction was lost, and with it steering, resulting in untold deaths, maiming, and life-changing injury?

    Oh yes, where is that opportunist Ralph Nader on all this? Yes, he properly decried the Chevrolet "Corvair" rear-engined car for "jacking"; but he totally ignored the Volkswagen "Beetle" and the Citroen "Deux Chevaux" for having the self-same flaw. Thanks, Ralph; you think you did good, but all you did was make a market for even more dangerous imports, initiating the death of the automotive industry in the US.

    Yes, if you own a front wheel drive car, beware; it’s a death trap compared to any properly engineered car. But that’s what you bought, and as the Romans used to say, "Caveat Emptor."

    So, short story long Ron, I’ve never advocated the use of airships for transporting cargo, just as I’ve always pointed out that front-wheel-drive cars are dangerous as hell.

    Link to this
  40. 40. J. A. Dick 7:58 am 06/8/2011

    The only "green" use of airship technology is the same one I’ve always promoted, and continue to promote; the use of airships as near-earth "satellites" – awareness platforms, so to speak. Take a cruise over the rain forest, the desert, or any other of Nature’s wonders, in a Teddy Roosevelt way: Preserve and enjoy.

    Link to this
  41. 41. skyship007 5:06 pm 06/8/2011

    Hi Folks,
    The more I read this article the more I think it must have been sponsored either by the helicopter industry or the tilt rotor fan club. No one associated with the serious hybrid companies like Hybrid Air Vehicles from Cranfield has suggested that the initial use of HAV’s will be to compete with normal air frieght, as that would require a very large HAV which is more efficient and an increase in fuel price. The initial uses are long range point to point cargo, fuel efficient heavy lift and ultra long endurance surveillance. The US military that is funding programs like the LEMV one, are not idiots and they have done a lot of reasearch. The new generation of HAV’s have no competition in those sectors and there is a very big demand from the military and civil companies operating in remote areas with no airports or alternative means of transport.

    Link to this
  42. 42. J. A. Dick 6:53 am 06/9/2011

    Wow, skyship007!

    What an accusation!

    Are you prepared to back that up with any facts?

    My efforts are sponsored only by physics and a relentless pursuit of measurable facts. No one associated with any properly accredited engineering school would promote anything less; therefore I do believe that Cranfield University might take exception to your bandying about the the good name of "Cranfield" as if Hybrid Air Vehicles is in any way associated with that esteemed institution of learning.

    I did this article pro-bono, solely for the educational benefit of my fellow man. That you would accuse me of doing otherwise is a complete insult, and, quite frankly, constitutes a veiled attempt in the very least on your part, if not an outright prosecutable act of libel, sir.

    You have not refuted any of the physics I presented, arrived at by von Karman, peer-reviewed by the American Society of Mechanical Engineers, and affirmed by scholarly studies of members the Department of Mechanical Engineering of the Imperial College of London and peer-reviewed by members of the Royal Academy of Engineering.

    Therefore, I suggest that you apologise forthwith for your completely unfounded accusation that my effort is in any way "sponsored".

    The form of your response, sir, is typical of those who don’t have a leg to stand on in terms of independently verifiable fact; meanwhile, the erudite among the readership of this guest blog will no doubt see that you, as an "Airship & Blimp Consultant http://www.hybridairship.net", clearly and demonstrably stand to benefit financially from what you promote.

    The fact that you would use this venue to make false claims about my motivation in writing this guest blog is reprehensible – just in case I didn’t get my point across in the preceding paragraphs.

    I would strongly suggest that rather than make such accusations it would be the better part of valour to write your own article and get it published.

    If you can show how von Karman and the laws of physics and economics applied in my article are in any way incorrect – which is the proper way of Science – then please do so. Otherwise, do yourself and the world a favour by not making foolish accusations for all the world to see.
    :) <–= Yes, that’s me smiling and inimitably content, because again, "Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passion, they cannot alter the state of facts and evidence." -John Adams ‘Argument in Defense of the Soldiers in the Boston Massacre Trials’, December 1770.

    Cheers,

    J. A. Dick

    Link to this
  43. 43. J. A. Dick 7:06 am 06/9/2011

    Now, on less of a rant, do look at the link to "What Price Speed – Revisited". The authors didn’t include hybrid airships because they simply don’t exist commercially, period; but you can plot the points for data published by SkyCat on that graph; and lo and behold, they drop right in next to helicopters, which are significantly less efficient by almost a factor of three as compared to commercial airplanes, and fly about a sixth the speed.

    To repeat myself from previous responses, helicopters are not part of our transportation infrastructure, and never will be; they simply aren’t competitive. That’s why we don’t use them to transport cargo; and given that the numbers presented by hybrid airship manufacturers are similarly less efficient than competitive forms of transport, they too will never be part of our transportation infrastructure.

    I suggest next time you read me in full before intimating that "on the take" or "partial" to helicopters and tilt-rotors.

    Cheers,

    J. A. Dick

    Link to this
  44. 44. J. A. Dick 7:18 am 06/9/2011

    Smiles, everyone! Smiles! : )

    J. A. Dick

    Link to this
  45. 45. Johnny Onenote 12:31 pm 06/9/2011

    This is very interesting in light of the Sci Am article in early May that talks about dirigibles being a low carbon alternative to cargo planes (both authors seem to have a fascination with shipping pineapples). Unfortunately, the Hindenberg and the R-101 sealed the fate of these beautiful aircraft in popular consciousness.Here’s an interesting little podcast about the R-100 in Canada, which was doomed after the tragedy of the R-101 ~ http://bit.ly/jUB2Ei

    Link to this
  46. 46. skyship007 12:47 pm 06/9/2011

    http://www.hybridairvehicles.com/environmentalimpact.aspx
    Hi Folks,
    This article seems to have based its figures on the wrong type of airship engines and did not have the correct figures for modern hybrid air vehicles, like the HAV 304 or 266 that are now in the final assembly stage. The link above gives the true graphs for the HAV series, which show they are far better than a heavy lift helicopter in fuel consumption terms. They would not be if they used turbines but modern diesels are far better at lower altitudes. The US DoD set up a panel of experts who confirmed the graphs are correct and recent results from both minor aerodynamic and engine gearbox changes have been proven on the test bed at Cranfield to beat the projected figures.
    Regards JB

    Link to this
  47. 47. J. A. Dick 6:36 am 06/10/2011

    I find it interesting "skyship007", that you continue to argue with words when the numbers you publish on your website support von Karman and my article.

    You are correct in that piston-engine compression-ignition engines get roughly twice the efficiency in terms of consuming roughly half the pounds-per-horsepower-hour as turbines; this is why I advised CargoLifter that they were completely on the wrong track by proposing turboshaft engines: CargoLifter’s engineers "forgot" (by not doing due-diligence on the laws of physics) that the measure of a propulsion system’s efficiency is not the weight of the engines divided by the horsepower produced, but rather that it’s the weight of the propulsion system as a whole: Engines, propellers, gearboxes, fuel, and all the other ancillary items required to make a vehicle go from here to there.

    The break-even point by using compression-ignition engines vs. turboshaft engines was far less than a day; that is to say, the weight of a propulsion _system_ based on turboshaft engines consumed so much fuel that the CL160 would be better off to used huge, heavy, off-the-shelf piston diesel engines past a certain number of hours – let alone the multiple-day endurance promulgated by CargoLifter to their investors and the press. Typical turboshaft engines consume in the neighbourhood of 0.5lbs per horsepower-hour, while piston engines typically consume about half that, at around 0.25 lbs per horsepower-hour – which is why CargoLifter got it so wrong by thinking engine weight instead of propulsion system weight.

    So, let’s go back to what your data from your website says on the matter.

    Your website lists "HAV 606" as being capable of transporting a payload of "200 tonnes" (200 metric tons) at a cruise speed of 75 knots (38.7 meters/second) with four engines operating at a maximum continuous cruise rating of 6,000 shaft-horsepower (4 x 4,476 kW). The last time I checked, (4x4476kw)/[(200 metric tons)x(9.81m/s^2)x(38.7m/s)] = 0.236 at 86.6mph.

    Your website does not list an "HAV 304"; however, it does list an "HAV 366", with a payload of 50 tonnes with four engines operating at a maximum continuous rating of 2000shp cruising at 104 knots: (4x1491kW)/[(50 metric tons)x(9.81m/s^2)x(53.5m/s)] = 0.227 at 119.7mph.

    Roger Monk promoted the "SkyCat 20" at [4x448kW]/[(20 metric tons)x(9.81m/s^2)x(40m/s)] = 0.228 at 89.5mph, and the "SkyCat 200" at (4x4476kW)/[(200 metric tons)x(9.81m/s^2)x(46.3m/s)] = 0.197 at 103.6mph – both plotted on my graph.

    Your numbers fall in the same inefficient realm.

    Link to this
  48. 48. J. A. Dick 6:53 am 06/10/2011

    Meanwhile, "skyship007", I think it is worthwhile to point out that, according to your website, your CV as listed on your own website states that you attended a grammar school, a college of further education, the University of Kent whilst studying "Computers and Cybernetics", whereupon you worked as a "Delivery pilot for the Pilots Country Club…" and "Also several summers from 76 to 79, driving a fork lift truck to pay for additional flight training."

    I mean nothing ill by this; you’ve obviously accomplished some meaningful things and worked hard to attain them; but you are not an engineer, nor have you trained as one, nor have you attained a degree in the engineering sciences, nor have you practised professionally as an engineer.

    Free speech is a wonderful thing; but for you to decry me by implication as, essentially, bought and paid for by the helicopter industry or tilt-rotor fan club – and then subsequently not apologise for those implications while trying yet again to say you know what’s what…

    To use the vernacular here in the US: Really? _Really_?

    Again, dear readers, as the Romans said, "Caveat Emptor"; but even better, in the ways of Science, go measure and verify for yourself. Don’t have faith, don’t believe; trust if you must, but verify when you can.

    J. A. Dick

    Link to this
  49. 49. J. A. Dick 8:27 am 06/15/2011

    What a shame that the A-60 didn’t have a readily-operable rip-panel; then there would have been no loss of life. The pilot could have set his machine down and deflated, saving everyone including himself; no need for sacrifice.

    Heroic effort on his part? Perhaps.

    Should he have needed to be? Absolutely not.

    Link to this
  50. 50. J. A. Dick 8:19 am 06/18/2011

    It seems that an attempt has been made to "take me to task" (for my American compatriots, taken to the woodshed for a spanking) by Peter Ward, Chairman of the Airship Association.

    While I appreciate his polite words regarding acknowledgement of my expertise in airship engineering, the fact of the matter remains that basis of my article has nothing to do with my expertise; rather, it has to do with the laws of physics, which can be disputed independent verification that von Karman’s peer-reviewed use of the laws of Physics is in any way flawed.

    Mr. Ward states in his association’s publication that, "The Airship Association believes there is a rightful place for cargo carrying airships, but, at the moment, we envisage that to be only in nice markets."

    Belief, according to the Oxford English Dictionary, is first and foremost defined as "Trust, confidence; faith…"

    As the English philosopher Colin McGinn pointed out in Jonathan Miller’s "Atheism: A Rough History of Disbelief", belief "really just means what you’re going to take for granted, what you’ll act on, what you’ll assent to, what you might gamble on; that means you’re committed to it’s being the case. Belief is just an umbrella term to capture all the varieties of assent; of takings-to-be-true."

    Engineering, like all it’s brother sciences, does not deal in belief; it deals in the independently verifiable measurements that can readily be made. Is a bolt tightened to a certain torque? How many miles per gallon does a car get? How much energy does it take to produce a thing? How much energy does it take to use that thing to get something from here to there?

    Nothing in the hard world of science – and in the world of its child, economics – should ever be based on belief, opinion, or emotion. It is self-evident then that "Our judgement therefore needs to be measured and accurate." As a result, no amount of prose will insubstantiate basic, measurable engineering and economic data.

    Despite the wishes of Peter Ward, airships are – and remain – a sideshow; one that "The American government" (to use his words) has squandered the better part of a billion dollars in the last decade – all for naught.

    There is no such thing as a "niche market" – especially in tranportation. For instance, ships are a long outmoded means of trans-oceanic passenger transport, but they’ve always been viable as pleasure craft. Long-term surveillance was correctly migrated AWACS and satellites decades ago.

    The Airship Association supports the dreams of its readership at the expense of truth.

    Link to this
  51. 51. Andrew Carr 8:06 am 10/17/2011

    Fascinating article, but considering that modern high bypass gas turbines are only now approaching the efficiency of 1950s propellor driven aircraft means there is still a potential niche for airships. A B747-400F will burn 17+ kg/km of fuel while a similar cargo can be transported by airship for about 5 kg/km. That cannot compete with trucking, but would save a lot of fuel on long distance trans-oceanic transport.

    Link to this
  52. 52. johannes.eissing 10:48 am 12/12/2011

    Joseph,

    having read your article, my first thought was yes, this is what I expected. Airships have shown remarkable range and endurance records, but transport efficiency? Being that slow? In the end, your writings encouraged me to do some math on this question.

    The von Karman plot is interesting, but speed alone on the abscissa leaves some open questions in terms of costs resulting from being slow.

    Without success I looked after the word “productivity” within your article and the replies. Productivity is the product of payload and speed, being some kind of mass flow: An operator wants an answer the question of how to get x tons of payload transported y miles within a certain time.

    The ordinate in the von Karman plot gives an idea about propulsive efficiency: e.g. a pipeline, transporting a mass flow of oil, would need a certain amount of power to overcome friction losses. An airplane would have to overcome friction drag and induced drag, an airship mainly friction drag. The less power needed per unit productivity, the less are energy costs. In the same time maintenance costs and even acquisition costs are reduced, since power plants are a lion’s share here.

    Speed, seen in the abscissa of the von Karman plot, is already seen in the productivity (Pr). If one aircraft is half as slow, you would need two of them to ensure the same productivity. Or it must be twice as “big”.

    Size or number of vehicles in terms of acquisition costs is expressible in operational empty weight (OWE). As a rule of thumb, one kilogram (transport-) aircraft costs as much as EUR1000,-. So having a number for how much OWE is needed per unit productivity, gives insight in acquisition costs.

    What I did now is getting me, as you did, a few numbers for airships (I only used historical Zeppelin airships here) and for propeller airplanes such as Do328, DC-54, Super Conny and the like. What I need is OWE and maximum Takeoff weight (MTOW). The difference is then more or less useful weight (MUL), comprising payload (MPL) and fuel weight (MFU). A number for payload alone is not that useful, since you loose the info on range then. Further I need data on shaft power (SHP) and speed (v).

    I then plotted numbers for
    OWE/(MUL*v) = OWE2Pr versus
    SHP/(MUL*v) = SHP2Pr.
    Note I didn’t use payload to compute productivity, but useful load to account for range. It turned out, that airplanes would need only about 50% of the OWE that is needed by airships for unit productivity. But they are consuming as much as 2.5 times the power to do so.

    Ok, this was for useful load, comprising both payload and fuel mass. A vehicle consuming more power per productivity would have to carry more fuel, and hence less payload. This can be dramatically seen in a payload range diagram.

    I simplified my range computations for airplanes. Instead of employing a fancy Breguet range formula, I hunted for comparable ballpark numbers. I computed range as a function of fuel to useful load ratio, brake horse power specific fuel consumption und shaft horse power to productivity ratio:

    R = MFU2MUL/(BSFC*SHP2Pr)

    Where MFU2MUL is the fuel mass to useful load ratio, BSFC is the brake horse power specific fuel consumption and SHP2Pr is the shaft power to productivity ratio.

    Plotting the payload to useful load fraction versus range reveals the potential benefit of airships: The range is about 3.5 times higher than the airplane range, given the same payload speed product, known as productivity.

    These are only simplified computations on quickly collected data, but they make airship at least look better than the von Karman plot does. You only need to build them big enough, and you must withstand the whish to reinvent the wheel. This is all based on proven technology.

    Best Regards, Johannes

    Link to this

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