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The Age of the Airship Returns?
Popular in Victorian and Steampunk fantasies, airships and zeppelins evoke a certain elegance that most modern travelers don't associate with the airplane. Some companies are capitalizing on that idea, and a need to move cargo by air in an era of ever-increasing fuel costs, to re-re-introduce commercial zeppelins. Popular Mechanics notes four notable airship designs, all with specific design purposes. One craft in particular, the Aeroscraft ML866, is being funded by the US government's DARPA group. It looks to combine the best elements of the helicopter and the zeppelin. "The Aeroscraft ML866's potentially revolutionary Control of Static Heaviness system compresses and decompresses helium in the 210-ft.-long envelope, changing this proposed sky yacht's buoyancy during takeoff and landings, Aeros says. It hopes to end the program with a test flight demonstrating the system. "
http://en.wikipedia.org/wiki/Cargolifter_AG
he wants his world of tomorrow back.
--- Grow a pair, liberals... stop letting the Republicans bully you!
No, the Stargate program has control of that. Go talk to Captain Carter and see if she can give you a few pointers.
The higher the technology, the sharper that two-edged sword.
(sorry, had to be said)
Table-ized A.I.
Cool.
Also, good perspective. If this thing is anywhere near the size of the Hindenberg, SIGN ME UP.
http://www.ciderpresspottery.com/ZLA/greatzeps/german/Hindenburg.html
The R101 doesn't get nearly the historical attention of the Hindenberg, but it was just as bad:
http://www.currell.net/models/r101.htm
Airships have their issues, but I recall reading somewhere that a blimp large enough to carry massive amounts of cargo can do so for the fraction of the fuel spent on ship-based transportation. Ships have to keep expending energy to push through water, but an airship needs far less power to keep a course through the air.
I see a couple hurdles though.
The first is designable around -- damage to the hot air or helium part due to lightning, or tears due to other factors. Having multiple "balloons" might help this situation, so if one is ruptured, the airship still can stay up, or descend in a fairly graceful fashion.
The second is a bit harder, but sort of related to #1. There are people out there (in most areas of the globe) who wouldn't mind taking potshots at an airship. It could be a drunk hillbilly who is playing with his new 30/06, or someone who has a RPG and is hoping to knock the thing out of the air completely. Oddly enough (and I have little or no aerospace expertise), I wonder if, even with major damage from a missile hit, a well engineered airship still can land gracefully (assuming the gondola isn't what is damaged.) Could an airship fly high enough so the chance of getting hit by ground fire be minimized?
Lastly there is a third problem. There is a ton of air traffic already. I wonder how hard it would be to factor in large, slow vehicles into the aviation corridors without impacting takeoffs and landings of jets and prop based traffic.
The paint theory is not credible. Anyway, it's definitely true that a big bag of unpressurized hydrogen in a thin skin is a dangerous quantity. The Hindenburg was an inevitable tragedy. Hydrogen is a bad idea in a dirigible.
Hydrogen is much cheaper, and is pretty safe if done properly. Hydrogen zeppelins of the first half of last century had an excellent safety record.
The Hindenburg disaster wasn't that bad. It only killed a few dozen people. And it involved other shortcuts that shouldn't have been done. The only reason that the Hindenburg seems so bad in retrospect is because there were a buttload of reporters at the right place at the right time (they planned to report a successful zeppelin trip), and because zeppelins don't die quietly, but rather in a huge exploding fireball.
Write your own Choose Your Own Adventure. http://www.freegameengines.org/gamebook-engine/
You must have missed the memo, Carter was promoted to Colonel a few years ago, and recently got appointed head of the Atlantis Expedition, so she's not even in this galaxy ATM. Also, Area 51 is not part of the Stargate program, though they do work together. Finally, I don't believe they were working on anti-grav tech.
About every 10 years or so, someone proclaims the return of the airship. The problems with airships are the same they have always been - high susceptibility to winds and difficult ground handling. Those problems are essentially insoluble - it's *lighter than air*. The combination helicopter/blimp had been tried at least half a dozen times, all unsuccessfully.
The hydrogen/helium thing not an issue. It's not going to use hydrogen. Whether that's what got the Hindenberg, or not, flying around with tens of thousands of cubic feet of exceptionally flammable gas, with a HUGE range of fuel/air ratios at which it can sustain ignition, isn't going to happen. It's a *bad idea* and wouldn't pass the laugh test for FAA certification.
Brett
It's in the ice cave just west of Crescent Lake. (But first, you'll need the Canoe from Lukahn.)
*ducks*
But seriously, wasn't it almost exactly 100 years ago that humanity learned an important lesson about mixing helium and airships?
Doesn't helium have the unfortunate property of being, oh I don't know... extremely flammable?
That's no airship, it's Thunderbird 2!
you are thinking of hydrogen.
= Hindendicer: explodes and chops all in one step
Table-ized A.I.
The trouble with blimps is that they don't compete with aircraft, since they are too slow. They compete with trains and trucks, but don't have the carrying capacity to do that, while they do have the maintenance cost of aircraft. So altogether they don't make economic sense and they likely never will.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
It was only about 40 years or so I read about this system. Of course, this was the Mad Scientists Club in Boy's Life magazine that competed in a balloon race and handled the buoyancy problem in this advanced manner. Maybe some of those Boy Scouts grew up to fly like Eagles and design airships.
(P.S. I also read Arthur Clarke's original short story Sunjammer in BL, before he had to go and change the title to the far less elegant The Wind From The Sun title, after some other author also used the same original title in another story that same year.)
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
But since love is irrational, then only a float is going to be at all useful.
I have been reading about the return of the Zeppelin (mostly for cargo carrying) in the science magazines ever since I was a small child. Popular Science or Popular Mechanics have seemed to have an article on the subject just about every year... for many, many years. So pardon me if I am skeptical! I will pay attention when I actually see a commercial version fly overhead.
And it lifts better too!
Of course vacuum would provide the best lift of all in the atmosphere. So why is it that my beautiful 21" crt monitor, which is little more than a big cube of vacuum, is so damn heavy?
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
helium is mainly obtained from natural gas fields [heloium apparently collects in these deposits] which means helium will probably be reasonably accessible for a while. now assuming we did run out of cheap Helium, we should be able to build airships that *ahem* use hydrogen or another light gas to replace Helium. the big limitation of course is the danger of fire although a series of gas bags situated toward the outside filled with Nitrogen or some other reasonably obtainable relatively inert gas should give a decent buffer zone to absorb impacts and lessen the dangers of fire.
Sigs are too short to say anything truly profound so read the above post instead.
I've driven past Moffet Field, in California, which NASA uses part of, and seen several airship hangers. The ships I saw were not advertising or such, but appeared to be actual "workhorse" ships, whether for cargo or research, I don't know, but it seems airships have been around and doing useful work with almost no attention, so it is hardly surprising to me that more uses are being considered.
A very interesting use is being worked on by a company called JP Aerospace (http://jpaerospace.com/). Their idea is to build an airship-to-orbit system. Not in one go. It would involve transferring from a ground capable airship to an extreme high altitude airship.
Don't try to out wierd me, three-eyes. I get stranger things than you, free with my breakfast cereal. --Zaphod Beeblebr
If I remember correctly, they used aluminized layers alternating with iron oxide layers. aluminum can react with iron oxide in a thermite reaction. Iron oxide is the oxidizer and aluminum is the reducing agent, because of the violence of the reaction it is used in some cases to dispose of computer hardware to reduce/eliminate the risk of data recovery by unintended parties. That being true, it is certainly possible that the paint increased the risk of fire but the fact that the gas inside the balloon was very flammable didn't help anything. would the ship have caught fire if the outer coating wasn't flammable? probably eventually, all it takes is a tear in the skin of that ship to expose hydrogen to air and really at that point, it is only a matter of time before something causes ignition of the gas. OTOH, had the gas been helium, the only fire hazard would be the paint which if comprimised would be bad but likely a lot better than the whole ship catching fire.
Sigs are too short to say anything truly profound so read the above post instead.
That means it's not too long 'till the Golden Age of Colonic Irrigation!
Brett
don't worry, the fact that JET FUEL is just as explosive seems to be lost on everyone else....
If you mod me down, I will become more powerful than you can imagine....
Oh, please stop the FUD. From wikipedia:
"Despite the violent fire, most of the crew and passengers survived. Of the 36 passengers and 61 crew, 13 passengers and 22 crew died. Also killed was one member of the ground crew, Navy Linesman Allen Hagaman. The two dogs on board the ship also died. Most deaths were not caused directly by the fire but were from jumping from the burning ship. Those passengers who rode the ship on its descent to the ground survived. Some deaths of crew members occurred because they wanted to save people on board the ship. In comparison, almost twice as many perished when the helium-filled USS Akron crashed."
And you saying its not credible makes it un-credible because you are credible? Please back up your claim.
Over half of the people survived the crash. How many survive 747 crashes? Perhaps the 100+ tons of JET fuel in the wings and under the floor is not safer than hydrogen after all?
If information wants to be free, why does my internet connection cost so much?
Shouldn't all comments referring to the Hindenburg be modded "Flaimbait"?
I know what you did last summer. Just kidding, I don't work at the NSA.
Think how crushingly heavy it would be if you broke the vacuum!
Deleted
People also seem to forget that 2/3s of the passengers of the Hindenburg survived, and it was the only notable airship disaster, whereas most airplane crashes that involve fatalities seem to kill a good majority (if not all) of the passengers, and seem to happen at least once or twice a year lately.
Hunt your preferred prey at Aliens vs Predator MUD. Join the war at avpmud.com port 4000
There are around 43,000 traffic fatalities per year in the US. If we posit that a mere 60,000,000 people (only 1/5th of the US population) get in a car or cross the street on foot every year, that's a total death rate of about 0.00072%.
There have been 439 astronauts. 19 of them have died in flight. That's 4.5%, meaning you are, given the above incredibly pessimistic estimate, more than 6000 times as likely to die in a spaceship than in the rolling deathtrap called a car. And by the way, 14 of those 19 deaths have happened in the Space Shuttle, the most advanced manned spacecraft to currently fly on a regular basis.
You'll therefore excuse me if I find your risk assessment lacking.
But seriously, wasn't it almost exactly 100 years ago that humanity learned an important lesson about mixing helium and airships?
Doesn't helium have the unfortunate property of being, oh I don't know... extremely flammable?
Ladies and gentlemen, I give you the American public-school education.
And according to this link (no myminicity, I swear!), Helium is in danger of being in short supply due to among other things that it's not captured and recycled after use and while being available in big supply in the universe, the Earth supply is actually a bit limited.
According to the article it is an issue the next generations of scientist are going to have to struggle with. So maybe a Helium-based airship is not that good an idea, although I don't have to background to propose a different scheme.
You can make it from hydrogen. It's a bit tricky, though.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
If the skin burns, the ship goes down whether or not the gas inside is flammable, as the gas quickly escapes. I very much doubt whether the gas inside burns would make much difference. Especially as a lot of the fatalities with Hindenburg were people getting hit by falling debris (burning hydrogen would be escaping upwards - what they were hit with were either the skin or from the gondola) or jumping in desperation to avoid the fire.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
Talk to an engineer rather than a chemist!
What about a vacuum in a cleverly engineered light weight container? Or hot air? Buckminster Fuller had an idea of mile diameter geodesic domes that would levitate from waste heat. They only need to be 1 degree hotter than their environment -
http://en.wikipedia.org/wiki/Cloud_nine_(Tensegrity_sphere)
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
There is a Mythbusters episode that investigates this. They called it a bust. The paint did burn readily but it was nothing compared to tthe hydrogen exploding.
Article, episode itself.
A thistle is a fat salad for an ass's mouth...
If only love were rational then a float would be useful. But love, being irrational, is greater than all things - even long doubles.
Is written about in detail on my blog:
http://blog.myspace.com/khanz
Most of societies problems would probably be solved by mass production of Zeppelin houses. This may not seem realistic or reasonable to non-visionaries or cynics, but I really believe it, and have plenty of rational observation to back up this claim. Since the entire skin of the zeppelin would be cheap solar panels, the electricity used in the zeppelin (including lighting, heating, transportation, television) would mostly be environmentally friendly (and free!), and since the very nature of a vehicle by design is to be mobile, everyone would be effectively living "off the grid" which would translate into other environmental benefits, and better and more reliable power in the case of emergencies. Speaking of emergencies, Zeppelins are pretty much earth quake proof, tsunami proof, and brush fire proof, and with a reasonably good weather report, you could probably avoid most tornadoes and hurricanes by simply flying somewhere else for a while. In addition, zeppelins are slow, and, do not carry much momentum, so "traffic" accidents would probably be very rarely fatal for anyone involved, and with the wifi/gps/radar navigation system I have in mind would probably be extremely uncommon anyway. By removing cars and housing and the entire electrical grid out of the equation we have essentially solved global warming, traffic fatalities, homelessness, and maybe eventually even poverty altogether.
Now the biggest benefit though of living in a TRULY mobile home (and a home that was FREE to move, and could move over water, land, ice, and mountains!), is that in the event of a war, you could easily just fly somewhere else. In fact, at some point this evolutionary step from living in huts on land to yachts in the sky could prove to be the end of war completely. What's the use in fighting over land, when you live in the sky? The only thing to bother with of value on the land is going to be fruit, meat, vegetables, and water, and I think that those can be had fairly cheaply still, and will probably become even cheaper if our society chooses to make this transcendental step forward.
Myself personally I've been a fan of many places on the planet, and would love to be able to flit hither and thither with the comfort of my own bed, computer, closet, shower, and toilet immediately with me. I'd most especially like to do so while not paying rent, paying for hotels, and while having my own kitchen and fresh produce. I also would like to surf the internet, lounge in the hot tub, take a nap, play violin, or play mario kart while my home travels between Hawaii, Oregon, New York, Alaska, San Diego, and Ireland on the free power of natural sun light, and automatically by GPS auto pilot, and radar and wifi collision avoidance. Further, I'd like to enjoy the sunset and sunrise at all of these locations from a spot in the air, and maybe even on the top of my zeppelin on the sun deck that I have planned there, amongst the clouds and fresh perfect air free from the pollutants that rule our current carbon based economy.
The most frustrating part about this whole zeppelin utopia that I've created and have already been living in in my own mind, is that it's entirely feasible. Not just feasible, but almost childishly simple. It's a simple matter of running some numbers, running some computer simulations, and building/buying a factory and changing everybody's world, for the better. No more commutes, no more traffic, no more pollution, no more housing bubbles, no more traffic accidents, no more corporate slavery, no more censorship, no more war, no more poverty, no more stress, and probably eventually no more misery or suicide or prescription drugs like oxycontin (sp?). Just 6 billion happy people living with their families in luxury liners in the sky, with free electricity, internet, and water, drifting along in the sunshine from organic fruit stand to organic steak house to Irish pub for a night of
I hold very few opinions. I hold information based on observation and fact. If you wish to disagree, please use facts.
>>The Hindenburg disaster wasn't that bad. It only killed a few dozen people.
>Was the second sentence meant to support the first? Because I don't really think it does.
I think he's saying that the Hindenburg disaster didn't lead to a scarcity in the supply of people. The person supply being as plentiful as it is, we shouldn't be so afraid of spending it once in a while.
No it isn't. That is movie physics. One can make an explosive out of anything combustible, by mixing it with a suitable amount of oxidizer, so it is true that jet fuel is explosive in a sense. However it is not nearly as explosive as hydrogen. Hydrogen has a very wide explosive range. Therefore hydrogen can explode when it is mixed with some air, even if the amount air in the mixture is very low or very high. Hydrogen is also very flammable. So once mixed with air, any spark can initiate explosion. Hydrogen-oxygen reaction is also very fast, so its blast is powerful. And finally hydrogen oxygen reaction releases a lot of energy, on a mass or molar basis, so its blast carries more energy and is hotter than hydrocarbons of a similar mass or molar amount. OTOH to explode jet fuel, you have to mix it very carefully with the just right amount of air and initiate burning with a sufficient energy source. Exploding jet fuel is almost impossible in context of accidents, exploding hydrogen gas is the major mode of hydrogen related accidents. And even if you manage to explode jet fuel, it doesn't react as fast nor with as high exotherm, therefore explosions are milder. So, no, jet fuel isn't just as explosive as hydrogen, not by a stretch.
Gentlemen, you can't fight in here, this is the War Room!
I recall reading something about what amounted to a flying aircraft carrier. A zeppeline-like airship that launched biplanes.
The USS Akron (ZRS-4) based in Lakehurst, NJ and the USS Macon (ZRS-5) based in Sunnyvale, CA were helium filled rigid airships developed by the Goodyear-Zepplin Company (a joint venture of the Zepplin Company of Germany and the Goodyear Tire and Rubber Company) for the United States Navy. The airships were designed for coastal patrol and had the ability to carry and launch five small biplanes.
More info here
I work for the Department of Redundancy Department.
Because it is too small to have much lift. Depending on how it was built, you might need weights to keep a 21 meter monitor from drifting off.
You can't see ANYTHING from a car, You've got to get out of the goddamned contraption and walk...Edward Abbey
- The US is far and away the largest, if not the only, producer of helium; and
- we'll probably be out of Helium within 10 years.
As Helium is used, it must be recovered. If it simply left to evaporate, being lighter than air it will rise to the highest level of our atmosphere and there be stripped of by the solar wind. So once it's gone, it's gone--and there appears to be a finite supply, as we have only been able to extract it from natural gas deposits that have had the further advantage of being proximate to a radiation source.There are different estimates about how much more of it we have, and the Moon is a possible supply. But I sure wouldn't want to attempt to build an airship industry around it. By the time airships became feasible again, we may well be out of Helium by then (or in enough cheap abundance to make it the lift medium infeasible).
--
$tar -xvf
I'm the "this guy" mentioned above. I guess I should clarify what I wrote in my blog post. The ban on selling helium to the Nazis WAS based on military priorities. The presence of the swastika had nothing to do with the ban (other than making sure there wouldn't be an exception made). Eckner admired the Americans and was less-than-thrilled by the Nazis (although he accepted their funding). The economic realities of the day meant he had to place the swastika on his airships, thereby "dissing" those he admired. Sorry for any confusion.
In the 1980s, my dad worked on a project for the Piasecki Aircraft Corporation. It was called the PA-97 Helistat. There are some pictures and info about it on the Piasecki Aircraft website. It was designed to lift heavy objects using a derigible and a few helicopters. Unfortunately, the helicopters motor frequency became resonant with the flimsy frame structure and it fell apart, killing one pilot. One thing that has always intrigued me is that the German version of wikipedia has a lot more info about the Helistat than can be found anywhere else: link.
The Right Reverend K. Reid Wightman,
I hear the sun's been doing it for years. Maybe we should ask it for advice.
Doesn't helium have the unfortunate property of being, oh I don't know... extremely flammable?
Ladies and gentlemen, I give you the American public-school education.
I noticed his handle is "MisterLawyer", which ought to explain the ignorance. He's probably been hitting his head on the ass end of too many ambulances.
You're using her as bait, Master!
I think we need to forgive MisterLawyer. He is after all not trained to think, but to see possible opening for a liability case.
Gold sure is toxic. Occasionally lethal. Causes heavy metal poisoning, severe kidney and liver damage, the usual stuff. Treated by chelation just like lead and mercury and arsenic poisoning. But its elemental form is quite harmless due to the fact that it'll just sit there and not react, since its in a non-soluble, non-ionic form, and doesn't react with anything typically found in a human body. Lead is bad for you because even in its elemental form, there are a number of things in your body that can react with it and form soluble compounds, though I heard somewhere that this isn't much of a danger for say, a bullet lodged somewhere, mostly just a danger of ingestion (though this is not true for lead salts like those used in paints and glazes, which are already in a soluble form). Swallowing a gold ring, on the other hand, isn't dangerous, since it won't react in your stomach and will remain just a chunk of gold. Gold salts (which is what they call soluble gold compounds even if they aren't technically a salt) are used in electroplating stuff, as an anesthetic agent, and for treating arthritis, and these are the danger. Since gold won't become soluble in your body, having a soluable form of gold enter your body is a bad thing, but its the ONLY way to get gold poisoning. I seem to recall an episode of House where a woman was poisoning her husband with whichever gold compound is used to treat arthritis. House might not always be a good source, but gold poisoning from overdosing on this medication is a very real danger. It's also a very real danger for those whose job it is to electroplate things with gold, and there have been a few rare deaths from lethal gold poisoning as the result of workplace accidents.
ASCII stupid question, get a stupid ANSI
It's in EVERY OTHER issue of PopSci or PopMech.
:-(
There are always beautiful artists renderings. They will be logging the Yukon, or carrying water-purification to South Asia.
I was a mad fanatic of Oswald Bastable, and Moorcock's Warlords of the Air. I wish the Chilean wizard, O'Bean, were as real as the next chap. But I fear 'tisn't so.
I wanted to start my own dirigible run from Africa to India: "Trans-Imperial Air Safari". Instead, a few intel agencies will use this for eavesdropping and sub-orbital comms stations.
"Flyin' in just a sweet place,
Never been known to fail..."
is that it's getting incredibly expensive as well.
Yup. I'm failing to see how the Hindenburg tragedy was "inevitable", given that it was, let's see, the 129th or 130th airship built by the Zeppelin Company, and none of the others met such a spectacular end.
It's also a fact that we regularly deal with much more dangerous materials in our technology. The solution is to engineer to minimize the danger. Accidents still happen. Planes have crashed, killing everyone onboard (unlike the Hindenburg, where most of the people onboard got off in time and survived, since a burning hydrogen filled airship is still a lot safer than a burning 747, merely containing hydrogen instead of the much more dangerous jet-fuel), but we engineer better and minimize the risks. All evidence points to a hydrogen-filled airship, even using yestercentury's technology, being safer in a crash/fire than a passenger jet. Today, we could do even better.
"Convictions are more dangerous enemies of truth than lies."
The 30-06 is still one of the best general purpose rifles around. In hunting, it easily handles powder and bullet combinations from a 150 grain deer round to a 220 grain round suitable for moose and large bears. There are now sabot bullets in the 95 grain region that make the 30-06 a good varmint rifle. It is a favored hunting rifle for reloaders because the cartridges can be fire-formed to custom fit the rifle's chamber, the brass is thick enough that they can be re-used multiple times, and the wide selection of powders and bullets allows custom tailoring of rounds.
In my experience, rural rednecks who know enough to acquire a 30-06 rifle are very unlikely to have it in hand when they are drinking. The redneck rule in southern Oregon is: no beer or other alcohol until the day's hunting is over; no handling of any of the guns after the drinking has begun. Break the rule and you find that none of the good old boys will hunt with you any more. My impression is that this is universal throughout rural USA and Canada, and probably world-wide. There would be fewer rednecks around if it wasn't for centuries-old customs like this one.
City-bred rednecks are another story: they do drink and shoot simultaneously. But they generally aren't savvy enough to buy a 30-06. They want something more macho like a .300 magnum to go with their huge fourwheeler that they don't know how to drive.
I seem recall hearing about an american air base which stored massive amounts of helium in the bedrock beneath the base. As memory goes there was an issue with closing the defunct base as selling the helium on open market would have crashed the helium market.
There's memory for you
lick the cancle button (at least thats what our Chinese QA says)
I've always had a soft spot for these things. A few thoughts:
Classic airships were terribly difficult to operate given the technology of the day. Landings were particularly difficult thanks to the strange concept of the mooring tower. Perhaps classic-era zeppelins could have been safer if they used a winch-down technology similar to helicopters on modern destroyers. In heavy seas, the helicopter cannot land conventionally. A cable is dropped to the deck where it is secured in a winch drum. The chopper pilot applies full throttle as he is slowly winched out of the sky. If the deck rises, he rises, and likewise falls when it falls. This prevents him from getting smacked into splinters by an unpredictable wave. For a zeppelin, a few mooring lines dropped from the air could leave it secured against errant wind gusts while it is winched down. Of course, we now have computer-aired control systems and could use rotating thruster pods like modern ships for three-dimensional maneuvering.
While hydrogen is probably still our best modern fuel, I'm curious as to what kind of unobtanium would be required to create vacuum airships, ones that don't just use a lighter than air gas but completely evacuated containers to create buoyancy.
Final thought: I hope they put more thought into this than the Germans who came up with Zeppelin NT. I'm still waiting for Titanic ME.
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
Christ, you people are as bad as the average Trekkie.
Besides I was just watching some Stargate reruns and got a little confused.
The higher the technology, the sharper that two-edged sword.
If the atmosphere would just behave itself and lie there docilely, or at least move all in the same direction at the same time, airships would make sense from an engineering point of view. But since the wind is not this cooperative, it is essential to build an airshipstrong enough to withstand the atmospheric equivalent of a rogue wave, and strength is the enemy of lightness. Size magnifies the effect of shearing forces. Also, travelling through the air faster than a stately drift causes vortexes and standing waves on the surface of the structure, a poorly understood phenomenon that is counteracted in "heavy" aircraft by just making the surfaces strong. Again, strong is the enemy of light. To make matters worse, the vortex patterns are speed dependent. In simple terms, a fast moving airship will tear itself apart. That is why blimps have a top speed of not very much, and rigid airships (the rigid part is about keeping the envelope from collapsing as speed increases) have a top speed of not very much more.
Maybe one day when fluid dynamics is better understood and strength to weight ratios have improved enough to get the safety margins into the right zone, the age of the airship will truly return. We are nowhere close to either of those at the moment. The concept art shown here for the Aeroscraft in particular is just stupid. Look at the massive concentration of weight right at the stern. There are good reasons why the most successful airship designs place the engines below the craft, in the middle. This contributes to stability and reduces stress on the structure, which otherwise would have to be heavier. Also the lozenge shape may look good on a magazine cover, but it reduces volume of the lifting gas in relation to surface area. Less gas is the same as more weight.
I have a lot of trouble believing that the designs shown have been subjected to any kind of serious engineering analysis. This is more about convincing gullible people to go take a flyer on a grand venture. See the pretty pictures and send your money here thanks.
To be sure, Zepellins really are back, at least a small number of them. They fly low and slow over Berlin. The design is very traditional, a stubby cigar shape with a nacelle underheath to which the engines are attached. These aircraft are not really good for much other than the spectacle, which in my opinion justifies the effort but this is a far cry from commercial viability as a mode of transportation.
Have you got your LWN subscription yet?
You bastard! Where's my +5 insightful?
Linux, you magnificent bastard, I read the fucking manual!
>"helium is twice (?) as heavy as hydrogen, so it has half the lifting power"
Nope.
Lifting power comes from the difference in density between the air and the gas in the balloon.
Air has a molecular weight around 15 so the difference between hydrogen and helium is the difference between 13 and 14, ie. not very much at all.
{nb. yes, it's a VERY simplified explanation}
No sig today...
and have decided to judge all Americans by the actions of those few [Congress]
Well, seeing as you lot are a democracy, that's kinda how it works.
Linux, you magnificent bastard, I read the fucking manual!