Original URL: https://www.theregister.com/2010/07/02/airship_king_thing/
'Huge airships to carry freight starting 10 years from now'
Ex UK.gov top boffin's amazing claim
Posted in Science, 2nd July 2010 13:07 GMT
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".
'Fresh fruit, vegetables, flowers and other foreign luxuries' will arrive like this.
King's remarks were reported by the Guardian this week. The former UK chief scientific adviser, nowadays turned big cheese at Oxford uni, was addressing a green biz forum there.
Small blimps used primarily for advertising are still in operation around the world, and a few "Neue Technologie" (NT) zeppelins with semi-rigid structures are used for joyrides. But big heavy-lift airships have not been built since before World War II; the era of the mighty rigids was ended by the disasters which befell the British R101, America's flying aircraft carriers Akron and Macon and then - most famously of all - the fiery demise of the Hindenburg.
According to the Graun, however, Sir David believes that the "US defence department has recently made a large grant to help develop" airship technology.
Presumably Professor King is referring to the recent award of the US Army's $517m Long Endurance Multi-Intelligence Vehicle (LEMV) deal. Much of the LEMV cash will go on developing surveillance systems, but it will also put one or more large "hybrid" airships - based on British technology in this case - into the sky. Sadly the LEMV will be optimised for endurance and height rather than payload, so it won't easily be turned into a cargo hauler.
There is another big-money US military airship project underway, the $400m ISIS strato-spy demonstrator project, but the solar powered radar-envelope ISIS ships will be even less suited to moving freight.
Nonetheless King reportedly considers that air cargo will begin to shift from its present carriers - generally cargo versions of passenger airliners - to airships as soon as ten years from now. This would happen because of the need to reduce carbon emissions, rather than any particular change in the economics of airships versus aeroplanes.
'Zeppelin explodes in New Jersey: Not many dead'
Oh, the uncertain amount of humanity
In classic Grauniad style, Observer environment editor Juliette Jowit writes:
Massive helium balloons – or blimps1 – would replace aircraft ... helium-powered2 ships could be carrying freight – and even passengers – in as little as a decade's time ... with a 90% reduction in greenhouse gas emissions ...In 1929 a graf zeppelin3 circumnavigated the planet in just over 21 days. The [pre-WWII] craze for blimps came to an abrupt halt after the death of many people when the Hindenburg caught fire4 in New Jersey, US.
Reading so many errors in such a short piece is painful, but even so we here on the Reg airship desk love the idea of a comeback by big proper aerial vessels. And hey, actual real boffins are saying it's on the cards!
Even better, Sir David and a couple of his colleagues at Oxford's Smith School of Enterprise and the Environment have done a study into the matter, which can theoretically be read in pdf here. We found the Smith School download a bit troublesome, so you may want to read it courtesy of Google Docs like this.
Unfortunately the Smith School report is short on hard analysis and long on misty speculation. It does admit that most of today's airline passengers, accustomed to moving about the world at close to the speed of sound, are unlikely to settle for typical airship speeds of 70 or 80 mph. Then in the case of cargo, rather more than half of all air freight today is carried aboard passenger flights - there would be little point shifting this to other platforms.
So we're down to say 40 per cent of air freight as our maximum possible scope. Air freight is thought to be responsible for maybe 20-25 per cent of aviation's carbon emissions. We might get rid, though, of 90 per cent of that by using airships instead of planes.
Whoa there - that figure of 90 per cent comes from would-be airship maker SkyCat. In a test case examining a notional shipment of Spanish strawberries to the UK, they admit that the actual fuel burn saving of using an airship would only be 40 per cent. The airshipheads go on to say, however, that because an airship flies at much lower altitudes than a modern jet its emissions cause less global warming - so the CO2 equivalence is down by 90 per cent.
Carbon emissions in an airship-cargo future would be ... 99.9% of what they are now. Woo!
That's debatable ground. Some analysts believe that an airliner's carbon is no worse, kilogram for kilogram, than carbon emitted down on the ground. Recent research says that the warming effect at height is enhanced by a factor of no more than 1.2 or 1.9. Even the reliably alarmist IPCC hasn't gone higher than a range of 2 to 4. (Full details with references on page 3 of this pdf.)
The SkyCat airship men seem to have calculated that a jet burning a given amount of fuel is no less than six times as damaging as an airship burning the same amount, in order to obtain their 90 per cent greenhouse effect reduction. Let's be a bit more reasonable and say 50 per cent - that's still great news for the planet, isn't it?
Not really. The whole of aviation accounts for only three per cent of emissions, and we're talking here about 40 per cent of air freight (which in turn is at most 25 per cent of aviation). So bringing in airships to replace all dedicated cargo planes would drop carbon emissions to ... approximately 99.9 per cent of what they were before.
If you want you could bump up aviation to 10 per cent of emissions - anti-flying people often like to, though this is based on some fairly wild assumptions. That might change the airship-freight-future carbon figure to 99.5 per cent of current: but then in reality an awful lot of air cargo can't usefully be shipped at 75 mph. So actually, no: you're talking about a minuscule impact no matter how you slice things up.
The environmental benefit here is basically nil. And the environmental benefit argument is the only new thing here, the only additional factor which might motivate big business towards airships and away from jets. The rest of Professor King's report is little more than a not-very-detailed rehash of airship ideas in recent times - and not always a completely accurate one, either. The prof and his colleagues, for instance, believe that the Lockheed P-791 prototype ship, built to contend for the DARPA "Walrus" project, is "undergoing flight tests".
Sadly it isn't. Walrus was cancelled in 2006, and the P-791 has been sitting idle in mothballs at Lockheed's "Skunk Works" for years. The active, funded airship projects at the moment - LEMV and ISIS - aren't Walrus type heavy lift low-altitude ships at all, and aren't really relevant here.
Much as it pains us to say it, there's nothing to see here. Airship lovers will probably be waiting a lot more than ten years to see the great sky-vessels return, it would seem. ®
Bootnote
Just to clear up a few points:
1A blimp is the term for a dirigible airship (not a free-floating or tethered balloon) whose fabric envelope maintains its shape by being inflated at a slightly higher pressure than the air around it. Blimps above a certain size become very difficult to make, and thus blimps could probably never be serious cargo haulers. In the grand old days, large airships were either semi-rigids - perhaps a blimp with a stiffening keel - or more commonly proper rigids. These latter enclosed a series of gas bags inside a vast, lightweight structure of girders and wires.
2Airships are not "powered" by helium, its buoyancy is merely used to support all or some of their weight. They still need ordinary motive power to move about.
3There is no such thing as "a graf zeppelin". Zeppelin is an alternative term for "airship", especially one manufactured by Graf [Count] von Zeppelin's original German venture - or its modern successor company. One such ship, the vessel which circumnavigated the globe in 1929, was named Graf Zeppelin in the old Count's honour. "A zeppelin" or "the Graf Zeppelin" would have been fine. Aargh!
4The Hindenburg was not a blimp and nor did she put an end to any "craze" for blimps. Her demise (in which 35 of the 97 people on board died) brought to an end the era of the rigid airship. Blimps continued in use and were employed in large numbers by the US Navy through World War II and beyond.