Would passenger dirigibles be feasible?

[TriPolar]

Originally Posted by CalMeacham

TriPolar, you didn't express yourself well, and it seems as if your objections are to just about any sort of lighter-than-air craft. (By the way, I don't think you're using "dirigible: correctly. The term means "directable", and applies to any propelled lighter-than air craft, not only rigid or semirigid craft).

In any event, there have been developments -- modern processor-assisted controls and algorithms give immediate feedback on attitude and control. Before we had them, flying wings and other innovative designs weren't practical because of instabilities . Now control of such shapes is matter-of-course. Also a greater range odf construction materials and much greater design experience (not only in computer simulation but also in wind tunnels. I knew a guy who did such design work on semi-rigid craft in wind tunnels, building models and trying them out) goes a long way in improving the safety of such craft. Certainly plenty of people feel that way -- there are societies pushing for lighter-than-air travel. And, as my link above notes, there are modern zeppelins flying i California and in Europe. It's a novelty thing, not a real transportation alternative, but that may change.

I see where we run into disagreement here. I've been using the traditional definition of dirigible to mean a rigid airship. Now looking at several references the term is being defined as you say. Maybe the recent rise of semi-rigid airships has made the term more flexible, because rigid and non-rigid aren't the only choices. Semi-rigids are like blimps, with no rigid super-structure, but use rigid stiffening members to maintain the shape of the envelope, allowing them to be larger or less pressurized than blimps. And lightweight materials have certainly made that more feasible and practical. Yes, all lighter than air craft have these problems, but semi-rigid and non-rigid craft cost much less. This lower cost reduces the problems of financing a large ship that can only be flown under limited conditions. And these ships come in under the size where a rigid ship is required, also reducing the cost of hangaring them. As non-rigid ships get larger, the envelope has to be pressurized more to hold shape, requiring a heavier bag, and increasing the density of the gas and reducing lift. The semi-rigid compromise allows a larger non-rigid craft without a complete super-structure. The zeppelins flying today are all semi-rigid craft, and much smaller than the old rigid dirigibles. And through the use of light-weight materials, can carry a heavier payload for a given volume of gas. This one, is a particularly interesting semi-rigid, and a hot-air (thermal) airship to boot. It uses umbrella type ribs to hold the shape, and a lightweight engine mounted on the tail which can be swiveled for directional control.

[BMalion]

If they had a smoking lounge, for me and my cigars, and a bar, I'd pay thousands to fly to the west coast and back.

[TriPolar]

Originally Posted by CalMeacham

TriPolar, you didn't express yourself well, and it seems as if your objections are to just about any sort of lighter-than-air craft. (By the way, I don't think you're using "dirigible: correctly. The term means "directable", and applies to any propelled lighter-than air craft, not only rigid or semirigid craft).

Looking around the web I see varied usage of the word dirigible that would imply rigid craft, but the official definitions make it synomous with airship, or a directable craft as you said. I've been an aircraft nut since I was around 5 years old and wanted to know what made a helicopter fly, and there was a time that airships were just called blimps or dirigibles (with zeppelins defined as a dirigible). Using the term dirigible for blimp would get the same kind of response as calling a whale a fish. I'll stop that now though. And I'm thinking of changing my user name to NotExpressingMyselfVeryWell. It always seems to be a hit or miss kind of thing with me. Ever since reading your brain out of body article I've wanted to ask you how you do it so well.

But seriously, you didn't pick up 'inflammable' That hit me right in the eye when I reread my original post.

[CalMeacham]

But seriously, you didn't pick up 'inflammable' That hit me right in the eye when I reread my original post.

It wasn't relevant to the point of discussion, and your meanings were clear.


My personal feeling is that "inflammable' should go away, in the interests of safety, and we should only use "flammable". Safety is more important than satisfying the nitpicking consistency sense of grammar mavens.

[TriPolar]

Originally Posted by CalMeacham

It wasn't relevant to the point of discussion, and your meanings were clear.


My personal feeling is that "inflammable' should go away, in the interests of safety, and we should only use "flammable". Safety is more important than satisfying the nitpicking consistency sense of grammar mavens.

That would be a good idea. Do you recall iMflammable used sometimes in the old days? Someone asked about that. We had an old can of turpentine in our basement marked that way when I was a kid, and something else I can't remember. It flustered my mother to explain both forms and the inconsistent use of in- as a prefix. She was the type who considered the world governed by inviolate rules. I just looked it up, and only found reference to excerpts of text where it could have just been typos.

[Lukeinva]

The US Navy had five dirigibles, they are in order: Shenandoah, Los Angeles, Akron, Macon and a fifth that was never named. The first four crashed and burned, and lives were lost. The fifth burned in the hangar before it ever got off the ground, and that's when the Navy abandoned the dirigble concept.

However, you might have a good idea if it were just for pleasure sailing ... say a two hour cruise over Manhattan. That could be a profitable business. You will need a rather large parcel of land to build a hangar and dock, etc.

[CalMeacham]

However, you might have a good idea if it were just for pleasure sailing ... say a two hour cruise over Manhattan. That could be a profitable business. You will need a rather large parcel of land to build a hangar and dock, etc.

Look up in the cites -- there already are such ventures with 45 minute-2 hour dirigible flights operating out of the San Francisco area and in Europe.

[Polycarp]

Originally Posted by lukeinva

The US Navy had five dirigibles, they are in order: Shenandoah, Los Angeles, Akron, Macon and a fifth that was never named. The first four crashed and burned, and lives were lost. The fifth burned in the hangar before it ever got off the ground, and that's when the Navy abandoned the dirigble concept.

However, you might have a good idea if it were just for pleasure sailing ... say a two hour cruise over Manhattan. That could be a profitable business. You will need a rather large parcel of land to build a hangar and dock, etc.

Well ... no, actually.

The first American ship was the US-built Shenandoah, ZR-1, which broke up when caught in a line squall over Ohio. The second was the British-built R-38, which was to have become the ZR-2. That was the one that never even got named, and it broke up during a test flight over the Humber estuary. The ZR-3, the Los Angeles, was built by the Zeppelin Co. for the U.S. in 1923-24 and flew uneventfully (except for the 'nosestand incident') for over eight years before being decommissioned in 1932. It was maintained "in mothballs" until 1939, when it was dismantled.

The LZ-4 "Akron" wrecked when flown out to sea into a storm front which drove its tail down into the ocean, which ripped off the lower fin and caused structural failure. The Macon, ZR-5, was stupidly flown int another storm with part of its frame damaged (from dealing with a storm while traversing a high pass in the Rockies), resulting in loss of its upper tailfin and damage to a few gas cells. Operator error resulted in the dropping of ballast and taking the ship above its maximum safe height.

[Lukeinva]

Originally Posted by Polycarp

Well ... no, actually.

The first American ship was the US-built Shenandoah, ZR-1, which broke up when caught in a line squall over Ohio. The second was the British-built R-38, which was to have become the ZR-2. That was the one that never even got named, and it broke up during a test flight over the Humber estuary. The ZR-3, the Los Angeles, was built by the Zeppelin Co. for the U.S. in 1923-24 and flew uneventfully (except for the 'nosestand incident') for over eight years before being decommissioned in 1932. It was maintained "in mothballs" until 1939, when it was dismantled.

The LZ-4 "Akron" wrecked when flown out to sea into a storm front which drove its tail down into the ocean, which ripped off the lower fin and caused structural failure. The Macon, ZR-5, was stupidly flown int another storm with part of its frame damaged (from dealing with a storm while traversing a high pass in the Rockies), resulting in loss of its upper tailfin and damage to a few gas cells. Operator error resulted in the dropping of ballast and taking the ship above its maximum safe height.

Thanks for doing all that research...my facts were indeed mixed up.

[WilliamWilsonsDoppelgaenger]

Originally Posted by Polycarp

There's one other, specialty niche for airships -- heavy-lift vehicles. Suppose, for example, you want to place a three-ton turbogenerator in a power plant adjacent to and old but intact dam, access to which is across a nature preserve, or you want to transport some large heavy object to a mountainside or mountaintop structure. Rather than building a road that could handle the three-ton load plus a vehicle that could haul it through the middle of the preserve, or up the slopes of said mountain, you use a LTA craft with adequate lift to bring the heavy object in -- and they can handle much heavier loads than helicopters.

That's pretty much what the idea of the Cargo Lifter company in Germany was. They were developing a semi-rigid airship as a heavy-lift transport, especially for regions with minimal infrastructure. It was financed to a large part by small investors and Zeppelin enthusiasts. They got as far as building a huge hangar and some smaller LTA crafts, before they went bankrupt rather spectacularly.

http://en.wikipedia.org/wiki/CargoLifter
http://www.aerospace-technology.com/...s/cargolifter/

Now the hangar is used for an artificial tropical islands holiday resort.

[alphaboi867]

Originally Posted by BMalion

If they had a smoking lounge, for me and my cigars, and a bar, I'd pay thousands to fly to the west coast and back.

Ironically that's the once feature that real, hydrogen filled, passenger airships had that's least likely to appear on a modern helium filled one. Both the Hindenburg and the Graf Zepplin II had one, and IIRC both the R100 and the R101 had plans for them. I don't think Goodyear put any designated smoking lounges in any of the passenger ship plans they came up with, but that's probally because any American vessel would've used helium thus allowing passengers to smoke everywhere (as was the custom at the time).

Originally Posted by Elendil's Heir

Just came in to say that the FX spy-comedy series Archer did a funny show, "Skytanic," on a modern passenger dirigible. You can see it on Hulu, I think.

I've gotta hand it to the writers of that episode. They addressed everything about how a modern rigid airship would operate and the economic challenges ("Who the hell want's a two-day blimp ride to London, which is our only route?"). I loved the contrast between the luxury suite (which was an actual hotel suite) and the standard cabins (basically a windowless train sleeping compartment, but still better than anything on an airliner).

[Xema]

Originally Posted by alphaboi867

... the standard cabins (basically a windowless train sleeping compartment, but still better than anything on an airliner).

It would, of course, be easy to have such a thing on an airliner if the economics of it made any sense.

[A. Gwilliam]

Originally Posted by TriPolar

Do you recall iMflammable used sometimes in the old days? Someone asked about that. We had an old can of turpentine in our basement marked that way when I was a kid, and something else I can't remember. It flustered my mother to explain both forms and the inconsistent use of in- as a prefix. She was the type who considered the world governed by inviolate rules. I just looked it up, and only found reference to excerpts of text where it could have just been typos.

Now that you've said this, I can definitely recall encountering "imflammable" being said to have this meaning. I can't remember if I've actually seen the word in the wild, though!

Assuming that you're not "MSL", here's a third person (scroll down to "Posting 6"):
http://www.bbc.co.uk/dna/h2g2/alabas...5?thread=98575

My guess is that from time to time the odd person with more logic than sense has tried to introduce "imflammable" as an unambiguous replacement for "inflammable". I don't think we need ponder too deeply as to why it's never caught on!

[Lightnin']

Originally Posted by Xema

True for giant airships of the past, but no currently existing airship can handle a payload as large as current helicopters.

...

The density of air and its drag on large objects is much the same today as in 1936. Without some as yet undreamed-of advance, airships are going to burn a lot of fuel to travel even at normal train speeds.

As I understand it, the larger the dirigible/blimp is the more efficient it is, at least in lifting power. And a larger surface area makes solar power (and thermal heating of the bag) more efficient, as well.

This sounds like a job for graphene sheets... assuming we'll eventually get the technology to mass produce them cheaply.

[Koxinga]

Still curious if there's any reason why a dirigible couldn't fly above the cloud cover and thus avoid bad weather. Assuming a pressurized cabin, of course.

Seems to me if you could get your dirigible up high enough and catch the jet stream, you could go reasonably fast.

ETA: In fact, if it were solar powered, it might be able to stay up there for very long periods and not even need to come down except for repairs. I'm picturing a super-sized dirigible made of future tech materials floating up there indefinitely, perhaps with smaller dirigibles going up and down as a shuttle service. It seems like a great science fiction idea, at least -- has it ever been explored?

[alphaboi867]

Originally Posted by Xema

It would, of course, be easy to have such a thing on an airliner if the economics of it made any sense.

True, and some of the First Class suites some airlines have put on the Airbus A380 are starting to resemble this (well, except for being all single occupancy). And of course the richest of the rich can just charter a private jet.

[Elendil's Heir]

Here are some images of the Hindenburg's smoking room. IIRC, passengers were forbidden to have matches or lighters; only the smoking room steward had them: http://www.google.com/images?hl=en&s...&aqi=&aql=&oq=

Some other pics that may be of interest: http://obviousmag.org/en/archives/20...indenburg.html

[billfish678]

Originally Posted by Koxinga

Still curious if there's any reason why a dirigible couldn't fly above the cloud cover and thus avoid bad weather. Assuming a pressurized cabin, of course.?

You gotta get pretty darn high to avoid the weather. And up high the pressure/density of the atmosphere is much lower than near sea level. Which means much less lift from your hydrogen/helium. Which means if you want to go very high, your airship needs to be way oversized for working down low. Or you carry lots of ballast and or you dump a a bunch of gas when you are up high to come back down again. Either way cuts significantly into you efficiency/operating costs.

[Polycarp]

Originally Posted by billfish678

You gotta get pretty darn high to avoid the weather. And up high the pressure/density of the atmosphere is much lower than near sea level. Which means much less lift from your hydrogen/helium. Which means if you want to go very high, your airship needs to be way oversized for working down low. Or you carry lots of ballast and or you dump a a bunch of gas when you are up high to come back down again. Either way cuts significantly into you efficiency/operating costs.

From my research on the Macon disaster: There is a maximum height at which a helium-filled LTA craft may fly under its own buoyancy, because of the extremely tiny size of the monatomic helium 'molecule'. For the technology of the time, this was around 3600 feet (~1100 meters). Above this, pressure in the cells must be reduced or helium will begin escaping into the thinner atmosphere. (Modern materials may improve helium retention and make for a higher ceiling.) It is possible to take an airship above this height by reducing 'static' lift (buoyancy) and flying the ship at cruising speed, which gives it a slight airfoil property, or by running the risk of rupturing cells. Hydrogen, being a diatomic molecule, does not have this stringent limitation, though I'd be inclined to think there is a somewhat higher ceiling on hydrogen lift. And, of course, hydrogen valved into the air is flammable (hydrogen not in contact with oxygen is of course not).

[scr4]

Originally Posted by Polycarp

From my research on the Macon disaster: There is a maximum height at which a helim-filled LTA craft may fly under its own buoyancy, because of the extremely tiny size of the monatomic helium 'molecule'. For the technology of the time, this was around 3600 feet (~1100 meters). Above this, pressure in the cells must be reduced or helium will begin escaping into the thinner atmosphere. It is possible to take an airship above this height by reducing 'static' lift (buoyancy) and flying the ship at cruising speed, which gives it a slight airfoil property, or by running the risk of rupturing cells. Hydrogen, being a diatomic molecule, does not have this stingent limitation, though I'd be inclined to think there is a somewhat higher ceiling on hydrogen lift. And, of course, hydrogen valved into the air is flammable (hydrogen not in contact with oxygen is of course not).

I'm not sure what this has to do with helium being monatomic.

Of course a balloon (or an airship gas cell) tries to expand as it goes up, and the outside air pressure goes down. High-altitude research balloons are only partially filled on the ground, so it has plenty of room to expand as it goes up. A rigid airship has gas cells inside the frame, so the same can be done (i.e. gas cells are partially inflated on the ground, and allowed to expand during ascent). Blimps need to be fully inflated to hold their shape, but they are equipped with ballonets; by removing air from the ballonet, you allow the helium to expand.

[Agnostic Pagan]

Originally Posted by billfish678

True enough. But the selling point has to be the experience and the view. Flying low and slow over somewhere pretty while you sit in a comfortable chair enjoying the view and having some decent drinks and food served to you would be an interesting and pleasant experience.

Days at a time where its the stuff INSIDE the ship thats supposed to entertain you? Yeah probably not.

Day trips or two days with a night would probably be what would fly demand/price wise. And at best it would probably be a very small niche market.

That is what I would be willing to pay for. I always thought a good niche for dirigibles would be floating restaurants. A short 4 hour cruise over Lake Michigan or Puget Sound while being served four course gourmet meal with views better than the John Hancock or the Space Needle. It would be a seasonal business which is where I have the hardest time making the numbers work though.

Plus the Hindenburg is stuck in the public consciousness even though the Goodyear Blimp has operated safely for a long time, and hot air balloon rides are still popular (no worse than sky diving and other 'air tourism'.)

Someday.

I also want to see someone build a true steampunk airship like in Stardust. (Though the balloon to ship ratio would have to be larger.) Bonus points if the captain is a closet cross-dresser.

If I ever win the lottery, I am calling some engineers and make it happen myself.

(This world has a severe shortage of the truly eccentric rich - I could tolerate them a bit more if they showed some more whimsy. I miss Fossett. )

[billfish678]

Originally Posted by scr4

Of course a balloon (or an airship gas cell) tries to expand as it goes up, and the outside air pressure goes down. High-altitude research balloons are only partially filled on the ground, so it has plenty of room to expand as it goes up. A rigid airship has gas cells inside the frame, so the same can be done (i.e. gas cells are partially inflated on the ground, and allowed to expand during ascent). Blimps need to be fully inflated to hold their shape, but they are equipped with ballonets; by removing air from the ballonet, you allow the helium to expand.

Yes, but take an airship that is designed to go between 0 and say 5000 feet high. Now take one that tries to get "above the weather", something like 25 to 40 thousand feet depending on your definition.

The second one is going to going to be significant bigger, or have significantly less performance, or be more costly to operate, and possibly all three at once. Probably something like a factor of 2 to 4 is my WAG. Given that even ground huggers aren't and probably never will be particularly cheap, thats a real penalty right there.

Oh yeah, if make a high flyer you gotta have the compartment pressurized for the passengers, which means a much smaller compartment (now its more like a cramped airliner) and that comparment will likely be heavier, reducing your allowable passenger payload (raising the cost even more).

[BMalion]

Originally Posted by Koxinga

Still curious if there's any reason why a dirigible couldn't fly above the cloud cover and thus avoid bad weather. Assuming a pressurized cabin, of course.

Seems to me if you could get your dirigible up high enough and catch the jet stream, you could go reasonably fast.

ETA: In fact, if it were solar powered, it might be able to stay up there for very long periods and not even need to come down except for repairs. I'm picturing a super-sized dirigible made of future tech materials floating up there indefinitely, perhaps with smaller dirigibles going up and down as a shuttle service. It seems like a great science fiction idea, at least -- has it ever been explored?

Sounds like an aerostat, see Orion Shall Rise by Poul anderson, great read.

[Gedd]

Originally Posted by Agnostic Pagan

That is what I would be willing to pay for. I always thought a good niche for dirigibles would be floating restaurants. A short 4 hour cruise over Lake Michigan or Puget Sound while being served four course gourmet meal with views better than the John Hancock or the Space Needle.

Maybe (when I win the lottery and can be one of your eccentric rich) I'll start here. There are other places where you wouldn't have to just be seasonal. You could also expanded to be like Hard Rock Cafe where you have them only in the most touristy places. Soft Air Cafe?

[Gray Ghost]

Originally Posted by BMalion

Sounds like an aerostat, see Orion Shall Rise by Poul anderson, great read.

Dean Ing's also played around with the concept; see "The Big Lifters," and some of his essays on future air vehicles.

[Agnostic Pagan]

Originally Posted by Gedd

Maybe (when I win the lottery and can be one of your eccentric rich) I'll start here. There are other places where you wouldn't have to just be seasonal. You could also expanded to be like Hard Rock Cafe where you have them only in the most touristy places. Soft Air Cafe?

That is true, I just like Seattle and Chicago, but it could be mostly year round in the south, or the Caribbean or the Med. Day trips among the Greek isles would be very cool.

Here's to hoping one of us gets a winning ticket soon!

Question: how does insurance work for hot-air balloon rides? Or airlines? Are they required to sign a waiver or is the operator liable? Or could I sell those airplane policies that used to be common?

Part of the business model is to get every safety certification possible, but I wonder about the insurance aspects.

[Polycarp]

Originally Posted by scr4

I'm not sure what this has to do with helium being monatomic.

Helium's inertness is important for two reasons: its non-combustibility, of course, but also the fact that it reacts with nothing whatsoever. (Except, of course, for getting caught in clathrates.) The helium 'molecule' is the helium atom, which is the nucleus and the innermost, K shell of electrons. It is miniscule compared to almost anything else at the molecular level. Over a certain pressure differential, it begins treating even the best natural elastomers like they were chicken wire.

[Xema]

Originally Posted by Lightnin'

As I understand it, the larger the dirigible/blimp is the more efficient it is, at least in lifting power.

Definitely true. But your giant airship is going to need a giant & expensive hangar, and be vulnerable to bad weather when outside it. It will not be able to carry even a significant fraction of the payload of a small train, and will be seriously energy-hungry at much above normal train speeds.

For lift capacity at very low speeds, it could be worthwhile. For transport, not so much.

[Martini Enfield]

I think that airships are in much the same category as flying boats- everyone agrees they're Very Cool, but the people who would most likely want to take trips on them (like me) also couldn't afford to pay whatever outrageous sum the fare would invariably cost due to the economics of it all.

[Xema]

Originally Posted by Martini Enfield

I think that airships are in much the same category as flying boats- everyone agrees they're Very Cool, but the people who would most likely want to take trips on them (like me) also couldn't afford to pay whatever outrageous sum the fare would invariably cost due to the economics of it all.

I think this says it fairly well.

I also believe there's a common misconception that airships should have an efficiency advantage since they do not have to expend energy to generate lift. Sounds good, but this falls foul of two facts:
1. Airships are necessarily huge, and thus always have lots of non-lift-related drag.
2. At cruising speeds, normal aircraft expend very little energy to produce lift (because drag due to lift is proportional to the inverse square of the airspeed).

The result is an inescapable efficiency disadvantage for airships. In a time of rising fuel costs, this is more or less fatal.

[N9IWP]

Originally Posted by Martini Enfield

I think that airships are in much the same category as flying boats- everyone agrees they're Very Cool, but the people who would most likely want to take trips on them (like me) also couldn't afford to pay whatever outrageous sum the fare would invariably cost due to the economics of it all.

When Chaulks was flying Mallards, I think thier prices were reasonable (not the cheapest, but not extreme either). But I could be misremembering.

Brian

[Martini Enfield]

Originally Posted by N9IWP

When Chaulks was flying Mallards, I think thier prices were reasonable (not the cheapest, but not extreme either). But I could be misremembering.

When I say "Flying Boats", I'm talking British Empire Airways and Pan Am Clipper style flying boats operating long distance, multi-stop routes between the far corners of the world with stopovers in exotic places where one can either wear a pith helmet or swim in a coral blue sea.

I would love- love- to fly from Australia to London aboard a Short Solent flying boat, stopping off in places like Singapore, Bombay, Cairo, and Marseilles on the way. But even then, the cost of a flight was something insane like $10,000 in modern currency and it took a week and a half at least. It's the sort of thing you'd do once for the experience, but seeing as neither British Airways nor Air France were able to keep a plane that could cross the Atlantic in three hours commercially viable, how many people- realistically- would regularly pay $10,000 plus for a one-way flight to London or Sydney that's going to take over a week? Not many, sadly.

[Elendil's Heir]

This might be the next best thing to actually taking a zeppelin trip: http://www.clevelandfilm.org/festiva.../2011/farewell

[Elendil's Heir]

The Atlantic magazine on the 75th anniversary of the Hindenburg's loss - some great pics: http://www.theatlantic.com/infocus/2...saster/100292/

[BMalion]

Originally Posted by Elendil's Heir

The Atlantic magazine on the 75th anniversary of the Hindenburg's loss - some great pics: http://www.theatlantic.com/infocus/2...saster/100292/

Thanks!

[Sailboat]

Originally Posted by Xema

The density of air and its drag on large objects is much the same today as in 1936. Without some as yet undreamed-of advance, airships are going to burn a lot of fuel to travel even at normal train speeds.

Yeah, but they'll hover much more fuel-efficiently than helicopters or Harriers. So all we need to do to justify them is to think of "hover-intensive applications."

[Daylate]

As an item of interest, I have a book on rigid dirigibles that contains the information that the Hindenberg could cross the Atlantic on $37 worth of fuel. If challenged on this, I'll see if I can look up the reference tonight.

Also the Germans during WWI developed a series of "high-flying" airships that could cruise at 20,000 to 27,000 feet (or thereabouts). I understand that this was not too pleasant for the crew.

[FeAudrey]

Originally Posted by Lukeinva

... The US Navy had five dirigibles ... (some information) ... the Navy abandoned the dirigble concept ...

Originally Posted by Polycarp

... (some clarifications) ...

After World War II, the Navy continued messing around with airships, running blimps out of Lakehurst (N.J.) Naval Air Station (the dirigible base, and site of the Hindenburg crash):

http://www.naval-airships.org/Defaul...?pageId=993560

I can remember these babies flying over the Jersey shore -- the crews in the gondolas would wave to us kids.

And! Just last year:

http://www.militarytimes.com/news/20...esumes-102711/

[Elendil's Heir]

Originally Posted by Daylate

...Also the Germans during WWI developed a series of "high-flying" airships that could cruise at 20,000 to 27,000 feet (or thereabouts). I understand that this was not too pleasant for the crew.

Too cold? Air too thin? Too much bucking up and down? Something else?

[Exapno Mapcase]

Originally Posted by Daylate

As an item of interest, I have a book on rigid dirigibles that contains the information that the Hindenberg could cross the Atlantic on $37 worth of fuel. If challenged on this, I'll see if I can look up the reference tonight.

I'd like to see that reference. The Hindenburg used 4 Daimler-Benz 16 cylinder DB 602 diesel engines. Even at the price of diesel in those days, you probably couldn't power those suckers up for $37, let alone fly across the Atlantic.

Airships.net claims that:

Hindenburg’s normal cruise setting produced 820 h.p. and consumed 130 kg/hr of diesel fuel. If needed, Hindenburg’s engines could be operated up to 1520 RPM for full power, which produced 1050 h.p. and consumed 180 kg/hr of fuel.

That's around 10,000 kg of fuel.

Elsewhere on the site a poster claims that it also consumed consumed 1305 kg of lube oil on a trans-Atlantic flight.

Answers.com gives a different set of numbers that are even higher, but I suspect Airships.net is more accurate.

Hindenburg was equipped with 4 x Daimpler-Benz 16-cylinder diesel engines. Together, they developed 4 x 850 (3,400) horsepower for continuous cruising. Approximately, they consumed 550 kg of crude oil per every hour of work. So, the Brake specific fuel consumption (BSFC) of each Hindenburg's engine was 0.16 kg/(HP h). Typically, Hindenburg was capable to complete an Atlantic crossing (from Frankfurt to New York) in 60 hours and consume only 32,640 kg of diesel fuel. On her last voyage, Hindenburg completed the Atlantic crossing in 77 hours due to the fact that headwind was very strong and burned 42 tonnes of crude oil.

[bengangmo]

Originally Posted by Martini Enfield

When I say "Flying Boats", I'm talking British Empire Airways and Pan Am Clipper style flying boats operating long distance, multi-stop routes between the far corners of the world with stopovers in exotic places where one can either wear a pith helmet or swim in a coral blue sea.

I would love- love- to fly from Australia to London aboard a Short Solent flying boat, stopping off in places like Singapore, Bombay, Cairo, and Marseilles on the way. But even then, the cost of a flight was something insane like $10,000 in modern currency and it took a week and a half at least. It's the sort of thing you'd do once for the experience, but seeing as neither British Airways nor Air France were able to keep a plane that could cross the Atlantic in three hours commercially viable, how many people- realistically- would regularly pay $10,000 plus for a one-way flight to London or Sydney that's going to take over a week? Not many, sadly.

You might want to read a book called "Syd's (or Sid's) Pirates"

He was one of the original pilots for Cathay Pacific, flying DC3s on the transatlantic route. Really lovely guy...and some great stories to be heard

[t-bonham@scc.net]

Originally Posted by Xema

Definitely true. But your giant airship is going to need a giant & expensive hangar

But they've already been built, and are currently sitting empty. At Lakehurst, New Jersey, Mountain View, California, and Akron, Ohio (this one is still used sometimes by Goodyear for their blimps). You could probably rent those for a cheap price.

[MarcusF]

Originally Posted by bengangmo

You might want to read a book called "Syd's (or Sid's) Pirates"

He was one of the original pilots for Cathay Pacific, flying DC3s on the transatlantic route. Really lovely guy...and some great stories to be heard

DC3s on the transatlantic route? When was that? I wouldn't have thought they had the range.

[Orionizer]

Just curious, but instead of using helium or hydrogen, would it be possible to use heated air like in a hot air balloon? That way, the cost would be much less if this were possible...

[Daylate]

Quote:
Originally Posted by Daylate
...Also the Germans during WWI developed a series of "high-flying" airships that could cruise at 20,000 to 27,000 feet (or thereabouts). I understand that this was not too pleasant for the crew.

Too cold? Air too thin? Too much bucking up and down? Something else?

It seemed to be a combination of extreme cold and thin air - no pressurization.

[allyn]

These high flying airships were known as "Height Climbers".

Here are a couple of interesting links:

http://www.firstworldwar.com/airwar/..._zeppelins.htm

http://sped2work.tripod.com/zeppelins.html

[Daylate]

Quote:
Originally Posted by Daylate
As an item of interest, I have a book on rigid dirigibles that contains the information that the Hindenberg could cross the Atlantic on $37 worth of fuel. If challenged on this, I'll see if I can look up the reference tonight.

I'd like to see that reference. The Hindenburg used 4 Daimler-Benz 16 cylinder DB 602 diesel engines. Even at the price of diesel in those days, you probably couldn't power those suckers up for $37, let alone fly across the Atlantic.

The reference came from a book entitled "Ships in the Sky", copyright 1957, by the rather well-known author John Toland. I'll type out the relevant paragraph here (my $37 memory was off by a factor of 8). Toland was talking about some of the economics of dirigible travel.

"The season had also been a revelation to investors. The ship, twice the size of the Graf Zeppelin and more than three city blocks long, was as cheap to run as a Ford car. A scant 300 dollar's worth of crude oil was needed to carry a trip payload of seventy passengers at 400 dollars each, plus 26,000 pounds of freight at a dollar a pound. Air flight, reduced from the 2250 dollars charged per passenger by the Graf Zeppelin, was no longer for the rich alone but well within the budget of the average traveler."

The figure of 10,000 given earlier for fuel consumption on a typical Atlantic crossing works out to 22,050 pounds. Figuring 6.5 pounds per gallon, this comes out to3,392 gallons. So at $300 per crossing for fuel, we have a cost of 8.8 cents per gallon. I have no idea what oil cost back in the middle thirties, but this might be in the ballpark.

BTW, my inflation calculator says that $400 (the passenger fare) in 1937 would be $6,008 in 2010.

[t-bonham@scc.net]

Originally Posted by Orionizer

Just curious, but instead of using helium or hydrogen, would it be possible to use heated air like in a hot air balloon? That way, the cost would be much less if this were possible...

I can't see that being feasible, for something the size of the Hindenburg. Heated air provides much less lift than H or He, so you would need a much, much larger 'balloon'. Looking at hot air balloons, it seems like you need several times the volume of balloon vs. payload. Seems like it would take a really big balloon!

Then there is the cost of heating the air. Buoyant H or He stays buoyant; air must be kept hot to remain buoyant. That requires fairly frequent heating, possibly even continuous at higher altitudes. The cost of the natural gas (or other fuel) to keep the air heated would be pretty high. As well as the weight & space occupied by this fuel.

I don't see this as being cost effective.

[Elendil's Heir]

Originally Posted by Exapno Mapcase

I'd like to see that reference. The Hindenburg used 4 Daimler-Benz 16 cylinder DB 602 diesel engines. Even at the price of diesel in those days, you probably couldn't power those suckers up for $37, let alone fly across the Atlantic.

Airships.net claims that:

That's around 10,000 kg of fuel.

Elsewhere on the site a poster claims that it also consumed consumed 1305 kg of lube oil on a trans-Atlantic flight.

Answers.com gives a different set of numbers that are even higher, but I suspect Airships.net is more accurate.

What was the fuel capacity for the Hindenburg? How much fuel did they typically have left over when they reached their destination? Did they have a (required either by German law or company policy) safety reserve?

[Exapno Mapcase]

Originally Posted by Elendil's Heir

What was the fuel capacity for the Hindenburg? How much fuel did they typically have left over when they reached their destination? Did they have a (required either by German law or company policy) safety reserve?

Airships.net

Its length was about 803.8 feet; height, 147 feet; maximum diameter, 135 feet; fineness ratio (length over diameter), about 6; total gas volume, 7,063,000 cubic feet; normal volume, 6,710,000 cubic feet. Weight of ship with necessary equipment and fuel was 430,950 pounds; maximum fuel capacity, 143,650 pounds; total payload 41,990 pounds, and total lift (under standard conditions) was 472,940 pounds. Its rated cruising speed was about 75 statute m.p,h.; its maximum speed was slightly over 84 m.p.h. Passenger space was entirely within the hull.

That would indicate quite a reserve of fuel.