The long-touted idea of using airships to replace cargo aircraft is in the news again, courtesy of former head government boffin Professor Sir David King, who says "this is something I believe is going to happen". The 'Aeroscraft' concept 'Fresh fruit, vegetables, flowers and other foreign luxuries' will arrive like this. …
In ten years time
The airships will all be shot down by the Skynet controlled self-refuelling, self-rearming fighter drones anyway (from Lewis' story earlier today). So there's no point even thinking about spending any R&D cash.
All research must urgently be concentrated on the BSOD gun - which fires a combination of corrupted WiFi packets and viruses on all frequencies to cause the robot death machines to reboot - giving poor fleshies time to run away or permanently disable them.
And reusability vs. construction energy costs?
I'd guess a giant floppy airship takes less resources to build than a rigid highspeed airliner (or not?), but conversely the airliner can keep flying with just a regular wash plus maintenance of all moving parts, while the airship will need its fabric replaced every once in a while.
Any stab at these figures? My point is that replacing all (working) airliners with (newbuilt) airships would be a further CO2 & resources cost --- how does it weigh up to replacing them with more airliners?
So, I read a paper that says vapour trails left by aircraft reflect sunlight and so increase the Earth's albedo (have a cooling effect) and on the other hand that the release of CO2 by aircraft increases the Earth's temperature. Presumably one pretty much cancels out the other, so let's not talk about CO2. CO2 is the word that gets your research funded in the first place, that's all.
I imagine it would cheaper and slower to send goods in an air-ship (compared to an airliner), although we already have a cheap and slow method of sending goods called a Freighter. Otherwise, we could always use, say, Rail.
Can someone point out the business case for airships again?
Can we have the footnotes on the same page as the content that refers to them? Please?
Can somebody remind me about the avaiability of helium and it renewable status? I thought it was basically use it then lose it...
Correct. Helium is a very finite resource (as a monatomic gas with an atomic weight of 4 it easily escapes into space, unlike the heavier inert gases such as argon).
The Earth's helium supply comes from isotope decay in the crust, over millions of years. Certain geological strata can trap the gas.
Current helium reserves are expected to last 30-50 years, which is a big problem if you rely on superconducting magnets for i.e. NMR spectrometers or MRI scanners.
Helium is extracted from gases from oil wells (US great plains?), where it's actually quite abundant. The US govt. used to mandate its collection and storage. But some years ago they decided they had enough, and stopped collecting. So, while you're correct there are limited reserves, there's still quite a lot underground.
All we have to do is extract it, and not piss it away in floating balloons for kids or making silly voices...
Use Hydrogen in new airships, not helium.
Hydrogen is by far the best gas to use in airships, yes it can catch fire and burn, but it's half the density of helium, and MUCH cheaper.
It's perfectly reasonable for a safe hydrogen airship to be built with modern technology. Yeah it could go bang if someone deliberately shot something into it, but if you're looking for something to transport cargo primarily rather than people then it wouldn't be too hard to design some kind of crew escape module (assuming that these things would need a crew at all).
Not bang, but whooof, surely
IIRC, most of those who died in the Hindenburg accident did so because they jumped, and died on impact. Those who rode the ship down (then ran like hell) survived. That was, at least in part, because burning pure hydrogen goes up, not bang.
So yes, a safe hydrogen airship sounds OK to me. If they could get it up to maybe 150MPH it would even make a reasonable cruise liner, since the limit would be weight, not space.
Surely the real market for these things is as freighters which can bring us the essentials of life (Spanish strawberries and Shanghai iPhones) much more quietly than a 747?
According to a not-very-reliable source (something like a Horizon programme), the Hindenberg probably caught fire because of the paint used on it, rather than the hydrogen. Though the hydrogen probably made a difference once it got going.
Drawing further on my collection of half-remembered factoids, I believe it's not that easy to set an airship alight by shooting things at it, because they tend to go right through and just end up making it a bit more leaky.
Not a good theory
The theory is that the aluminium powder in the doped cover (which was there to reflect heat) reacted with an iron oxide primer. As good old-fashioned chemistry practicals taught us aluminium + iron oxide + heat -> aluminium oxide + iron + mind boggling amounts of heat. This is the thermite reaction.
The theory falls apart because the concentrations of iron oxide in the primer would not have been enough to start the reaction.
It also conflicts with evidence from the ground that report seeing a glow deep inside the airship before the fire became visible on the skin; and that the ship was reportedly stern heavy on her final approach, both of which suggest a hydrogen leak deep inside the craft.
At the end of the day, hydrogen doomed the ship; the Germans had just been incredibly lucky that they hadn't lost a civilian ship before then.
It was Mythbusters, the only show daft enough to actually try to replicate an exploding airship!!
All the descriptions of the fire stated that it was orange (didn't really come out in the black and white pictures), had it been a hydrogen fire then it would have been blue.
Either way if the Zep had been built today regardless of whether it used Hydrogen or Helium it wouldn't have had the same design problems.
Hydrogen does not easily go bang
even if you shoot at it. The small holes caused by bullets of WW-I fighters often failed to have an impact. Even phosphorous-coated tracers had difficulty bringing the zeppelins down, because oxygen mixed with the hydrogen neither quick enough or in large enough quantities.
You need a fairly powerful incendiary to make these things explode.
not understood : do you mean that, though there was a fire of the whole thing, hydrogen did not burn ?
Is constantly released from radioactive decay, largely from shale oil deposits. We've heard this airship crap since the 1930s. I'll believe it when I see it.
By your methodology oil, coal and natural gas are renewable fuels.
Helium is being created constantly at a rate of about 3000 tonnes per year across the Earth. Unfortunately we're using ten times that much every year.
Ya but that's 3000 tonnes of helium, how much does it really weigh??
I believe that we are using several billion times more natural gas, coal and oil than is being produced. So your analogy doesn't bear examination, most industrial helium is derived from distillation of natural gas. the 3000 tonnes you refer to is that liberated from the earths rocks etc naturally.
Quite a few assumptions there.
A "floppy" airship might need fabric renewing due to UV damage, like balloons, parachutes and paragliders do. But for a rigid airship, there's unlikely to be much degradation of the airbags over time. It'd be covered with a lightweight metal skin, which would be unstressed and wouldn't need any maintenance at all (except the regular wash).
Airlines need vast amounts of TLC though. Not just maintenance of all moving parts, although this is clearly the major element - jet engines aren't cheap to build in the first place, nor to rebuild after their rated flying hours, plus maintenance on all control surfaces. But also there's the vibration on wings and tail ("vertical stabiliser" for the initiated) which needs to have a close eye kept on it (look out of the plane in flight and see how much the wings wiggle - I guarantee it'll worry you).
And as far as renewal goes, airlines regularly renew their fleets anyway. When you've got aircraft flying umty-tum thousand miles a day for a few years, getting aircraft with lower fuel consumption is a very big deal indeed. Planes today are generally slower than they used to be 30ish years back, but they take so much less fuel that more hours' pay for staff isn't a big deal.
Re the article though, it makes the assumption that airships would be powered by avgas. Understandable - but not necessarily right. If you're flying above the clouds and you've got an airship with a few thousand square feet of surface area, PV panels and electric motors are a natural choice. Bit of a bummer at night, sure, but you're neutrally buoyant in the air so you don't need power to stay up - a bank of batteries will store excess leccy during the day and you're laughing. Suddenly the carbon budget looks a whole lot different.
It's not so much the wings wiggling
When I last looked out of the window of a 747 it wasn't so much the way the wings were flapping as much as it was the way the engines were bobbling around on their mountings that worried me...
Wobbly wings; and solar power
An anecdote that did the rounds a good few years ago: A passenger looks out of the window during turbulence, sees the wings flexing, and grips the seat in front of him, knuckles white with fear. The woman in the next seat notices this, and says kindly: "Don't worry, they're meant to do that; I'm an off-duty air hostess and I know about these things." The man replies "And I'm an off-duty engineer from Boeing, and they're not meant to go *that* far on this model."
More seriously: would it be possible, and cheaper than PV, to concentrate the sunlight through a transparent upper part of the hull, onto steam tubes, and drive turbines from that?
You could perhaps use an air-cooled stirling engine with that design.
No need to boil water then!
Not sure about the weight levels, but given the surface area and the need for
a skin anyway, could solar tip the energy balance?
During the day of course....
Actual boffin's actual speculation
If these airships come to pass and reduce jetliner traffic significantly, it might have a significant impact on global warming, but not in a good way. In the days after the 911 attacks when air traffic over the US was stopped, ground temperatures rose due to the lack of contrails increasing the Earth's albedo. I can't imagine an airship producing a contrail.
Do something new instead of redoing the 1920s
Us hydrogen(*). Use fuel cells to turn some of it into electricity for the propellers. Coat the top of the thing with PV cells so that coasting downwind above the clouds it can refuel itself. Aim for a smaller vehicle which can displace road/rail feight as well as airfreight. Make then automatic to save the cost of a human pilot. Control bouyancy by pumping gas into/out of high-pressure tanks. Say goodbye to the ecconomic restriction that any useful enterprise has to be on a decent road/railway/near a port/near an airport.
(*) Yes, I know it's combustible but then so is aviation fueel, which has a higher energy density and a sits around in puddles waiting to burn rather than dispersing.
Just burn the hydrogen
they wanted to do it for the R100 and R101 but it was easier to use petrol and diesel engines
You get helium from liquifying air and separating out the relevant bit. There's limited supplies of helium in the atmosphere, but if/when it escapes from your balloon, it just goes back into the atmosphere. Given vast amounts of time and low enough gravity, it would all eventually escape, but Earth's gravity is enough that it mostly doesn't. "Renewable status" would mostly depend on the power used to do the air-liquifying.
Oh no it doesn't
The Earth is unable to hold on to helium because helium tends to migrate to the upper part of the atmosphere where the thermal velocity of helium atoms exceeds escape velocity. Some is also lost by ionisation through the Solar Wind.
There is no primordial helium on Earth which is easy to prove since He3 is practically non-existent down here whereas its plentiful on Jupiter which is big enough to hold on to its original helium.
From gas fields..
It's found in natural gas, in varying quantities:-
The economics and timeliness should also be compared to marine transportation for certain goods, which would potentially expand the available freight market for the airships. Faster than water based ships, potentially larger and more efficient than road freight and more direct than rail freight with lower infrastructure costs than all of these. Airships would probably be useful in lowering costs for quicker than shipping, but slower than flying freight.
Even better than blimps
Ekranoplans - much more fuel efficient than a plane and much faster than a ship. For those of us that grew up on Gerry Anderson TV they also have the added advantage of looking seriously awesome:
(yes those are ALL engines!)
Remember that airships and other airliners can also fly over land too, including mountains. I don't see an ekranoplan managing that very well.
Anyway, how can something with *that* many engines be efficient? :)
They work, it's just a slightly harder landing when they break
How well they cope depends on what type of Ekranoplan it is
Q : Anyway, how can something with *that* many engines be efficient? :)
A : By not using all of them
>'Fresh fruit, vegetables, flowers and other foreign luxuries' will arrive like this. …<
Whoever wrote this line doesn't check the country of origin on the labels of the fruit and veg in the supermarket. For example, peas and runner beans - from Kenya or Ecuador - by airship? Not only won't it be fresh, but it is likely to be covered with hairy mould by the time it gets here.
The Year of the Airship
I'm with Efros on this. It's been the Year of the Airship every other year throughout the decades, and it's never happened, for simple economic reasons - nobody can get the business numbers to work. The economic value of getting cargo to its destination quickly far outweighs the saving from cheap transportation. Which is why there's so many bloody container trucks on the roads, so little cargo on the canals, and so few airships in the skies.
To a point, Lord Copper
"Which is why there's so many bloody container trucks on the roads, so little cargo on the canals, and so few airships in the skies."
Doesn't explain why there's so many gigantic cargo ships floating about in the Pacific, though, does it?
If the cargo can travel so slow...
.....wouldn't it be better going by sea on a container ship?
Isn't the whole point of air freight the high speed\short delivery time.....
Cheaper and better than ships?
I suspect that a sea going ship uses much more fuel per kilogram of freight than an airship. It also is slower and easier to hijack. It can only call at a port, whereas an airship can be loaded/unloaded inland.
But I think you're right - the airships will compete with maritime transport rather than with the airplanes.
About 5000 tonne/miles per tonne of fuel, roundabout. Much more efficient than you'd suppose.
Even better if you use the wind to power some of the journey...
It will not hit aircraft cargo, it will hit ferries
The main candidates for an airship replacement will not be airplane shipments. This will be all those lorries that get loaded at Bilbao, Hook of Holland and other similar places onto the small boat to bring some cucumbers and water melons to the supermarket shelf.
There is also a case for cutting down delivery times (and risks for high value goods) on some of the ship routes from the far East to Europe and the USA.
It will be interesting to see some numbers for these.
The Advantage of Airships
FIrst, they can scale up to infinite weight capacity. So the US Military has a few ideas about transporting whole battalions on mega-sized airships. Most importantly, barring winds that would also knock helicopters out of the air they can land anywhere.
So if you're a military commander fighting an insurgency the advantages become clear right away. Do you try to secure and hold an airport with its easily vandalized runways, roads leading to and from that can be mined or lined with snipers, and deal with all the trucking and escorts? Or do you just drop several hundred tons of stuff wherever you want?
Likewise, if you're Walmart which approach do you prefer? Do you deal with cargo ships and containers, and trains, and trucks, and all the steps involved in moving dozens of containers from factory, to train, to ship, to train, to truck, to distribution center, to truck again? Or do you park a great whopping airship over the factories, winch up a mega-ton of stuff, and then coast over to the regional distribution hubs and drop them right there? You can't do fresh produce that way, but it makes sense for most other things. Well, given the time consumed moving stuff from one form of transport to the other it might be faster...
Foreign aid agencies are also mad for this idea. Using airships they can bypass bottlenecks like airports and sea ports that are often controlled by corrupt governments and airdrop stuff directly to those people who need the stuff.
"Using airships they can bypass bottlenecks like airports and sea ports that are often controlled by corrupt governments and airdrop stuff directly to those people who need the stuff."
Always assuming that said corrupt government doesn't have something that passes for an air force or, failing that, a couple of lads with shoulder launched AA missiles (or even el cheapo RPGs - airships are big and don't move fast) to piss on their picnic. In other words, exactly what stops them doing this sort of thing now with helicopters....
Infinite weight capacity LOL
Well, the size of the planet sort of imposes a practical cap to that. And while an airship the size of the continental US would look most impressive from a sci-fi movie buff's point of view, the cost of construction, maintenance, loading, moving and unloading it, not to mention the delightful effect it would have on the climate, means that we'll probably have to settle for floating cities as our theoretical maximum...
Seems like a good Idea to me - why not expand it?
We should also consider the huge amounts of shipping traffic that slurps around the world. These would surely be faster and, if big enough, be able to carry vast weights.
Also, wasn't the US going to vent its reserves of helium (http://www.theregister.co.uk/2010/02/05/helium_dome_forever/)
Seems a bit of a wasted opportunity there.
The blimp is derisible,
because to get to above a certain size, it needs stiffening to become more rigid.
If you ask me...
...this is all just a bunch of hot air.
I see. His conjectures, as reported, would pivot on the air-freight carriers' concerns about carbon emissions? Does the eminent boffin really believe as if the companies were really that concerned about carbon emissions? as if the whole carbon emissions game was not just a PR show, after all?
If I was running an air freight carrier, I think reason would serve to dictate that I'd be concerned about safety, foremost - which a well-maintained, well-piloted, effectoively unhijackable air-freight vehicle would be no great concern about , for safety again - and then, timeliness of transport. I don't believe the "carbon footprint" of the operation would ever enter onto the blotter.
Next-day air-by-blimp delivery? Sounds novel, it definitely sounds novel.