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Boeing-Skyhook Airship Faces Technical Challenges
waderoush writes "Since the Hindenburg disaster, dreams of giant airships capable of lifting heavy cargo have been restricted mainly to Popular Science covers
(with the notable exception of the Cargolifter AG failure) — until Boeing and a Canadian company called Skyhook announced on July 8 that they're building a 300-foot-long, helium-filled craft that will lift loads of up to 40 tons and carry them 200 miles. But an aeronautical engineer at the University of Washington cautions that there are still some big problems to be worked out with mega-airships, including their stability in turbulent weather."
Unless we run out of helium.
http://www.wired.com/wired/archive/8.08/helium.html
"At our current rate of consumption, Cliffside will likely be empty in 10 to 25 years, and the Earth will be virtually helium-free by the end of the 21st century."
I think they ALL crashed, except but one
As a child I watched airships sail over the pacific ocean and Tillamook Bay during the summer months. They would launch from the old military blimp hangers, only one would survive and it would go on to become the Tillamook Air Museum
And in high school they payed us to roll the bastards up for storage as they were no longer to be taken to the skies... So I can tell you sir, with the utmost confidence that all the airships did not, in fact, crash.
On the Oregon Cost born and raised, On the beach is where I spent most of my days
You mis-understand me. "people are trying to build an airship" is news-worthy even if they were built every day. But that's not this article's focus. This article focuses on how some other people (not the airship builders) mention problems with airship design. This article is about raining on someone else's parade.
What makes it particularly stupid is that these people who are predicting the builders' failure are doing so in an industry where virtually nothing has been done for decades. So essentially they are using antiquated data to argue against current endeavours. That's not only mean, it's retarded -- in the correct sense of the word.
Blimps are relatively small craft, made of rubberized fabric, they are in a different class from the larger airships with metal structures.
What am I missing?
That blimps have crappy aerodynamics, unlike a plane, and (especially when fully loaded) are going to get crap MPG.
In fact, a blimp with a 20knot maximum speed will get 0MPG in a 20knot headwind.
But, you're right, an SUV gets a 200mile range no problem. I too am underwhelmed.
My favorite quote doesn't fit into 120 characters. Now no one will like me.
The one method that you can trust to make sure you have not altered the past or diverted to an alternate world, is the relative absence of blimps.
At a rest stop in ohio, I noticed a sign about the crash of the shenandoah, an earlier version of these. Still, high time they came back. Skyhook is a brilliant name for it.
They should give Randall Munroe a free ride.
http://www.roadsideamerica.com/story/10432
America had four zeppelins of its own in the 1920s and 1930s. One -- the Los Angeles -- was built by the Germans, flew successfully for a decade, and retired with dignity. The other three -- the Shenandoah, Akron, and Macon -- were built by Americans, and each crashed less than two years after its first flight.
The first, and the only one to crash on land (and thus be suitable as a tourist attraction) was the Shenandoah. In September 1925 it was ordered to conduct an ill-advised publicity tour of midwestern state fairs. Less than 24 hours into its flight "the strongest airship in the world" was caught in a thunderstorm, torn to pieces, and scattered across the rolling hills of Noble County in southeastern Ohio. Amazingly, 29 of its crew of 43 survived.
Well a plane crash-landing from 100 ft. is usually going a couple of hundred miles per hour, getting to zero from that speed usually involves quite a bit of force.
A blimp crashing from 100 ft. while be going at much slower speeds and thus your chance of survival will be greatly enhanced.
Actually, chances of surviving a fire on the ground in an aircraft are quite low. Most of the fatalities in air crashes come from people who burn to death shortly after impact, rather than the impact itself.
I'm also reminded of numerous crashes which happen quite close to the ground which result in massive casualties--Tenerife, in particular, comes to mind. The greatest loss of life in aviation history came about because of a collision on the ground.
One of the things that makes airline accidents so deadly isn't necessarily the altitude, but the speed and the fact that these things are carrying so much damn fuel. I wonder which has more energy, the envelope of the Hindenburg or your average passenger jet fuel tank...
(Incidentally, airships can crash land from quite high altitudes with minimal ill effects. Because they're lighter than air, and contain so much lifting gas, even sizable holes leak quite slowly in comparison to the envelope volume, and the airship drops slowly. Fatal airship crashes have usually involved loss of control, rather than a sudden loss of lift; even the Hindenburg, with the entire envelope aflame, crashed rather gently.)
My problem with this aircraft is that for the complexity and cost of 4 heavy lift helicopters plus a giant airship all you get is twice the lifting power of a helicopter that was designed 30 years ago!? WTF? You can rent a Mi-26 today. This project doesn't make any sense.
Nice comment. Except for the part where you make the assumption that the ship is neutral with it's cargo. The article is talking about a ship that is neutral without it's cargo. Then it as rotors, just like an helicopter, for lifting the cargo. The rotors are compensating for the weight of the cargo. To go down, just slow the rotors. When you unload, the ship just stay there.
Try to read the article next time ;-)
"The ship will be filled with helium to make it neutrally buoyant-that keeps the vehicle and its fuel in the air-while the rotors provide lift and thrust to support whatever itâ(TM)s transporting"
2nd paragraph dumb ass.
One of the things that makes airline accidents so deadly isn't necessarily the altitude, but the speed and the fact that these things are carrying so much damn fuel. I wonder which has more energy, the envelope of the Hindenburg or your average passenger jet fuel tank...
Interesting question. I did some quick googling and math. I wasn't particularly careful, so corrections are welcome.
The Hindenburg had a gas volume of 200,000 m^3, at 0.089 kg/m^3 standard density of hydrogen gas, that is a total hydrogen load of 17,800 kg. Hydrogen has a high energy density of 143 MJ/kg.
A fairly heavily loaded 747 will be carrying 136,000 kg of Jet-A at 43 MJ/kg.
So, the 747 has more than twice the energy onboard, although smaller jets would be rougly equal, all depending on the fuel load. I also did not include the diesel onboard the Hindenburg (or its rather flammable aluminum paint).
One significant difference between hydrogen and Jet-A burning is that the hydrogen is going to rise once the gas bags rupture and not hang around on the ground like Jet-A.
Worst...sig...ever!
Heavy lift aircraft cannot lift 400 tonnes. The current world record is held by the An-225 carrying 250 tonnes. Most other heavy lift aircraft top out around 150 tons or so. Helicopters tend to top out around 20-25 tonnes (including fuel).
http://www.theregister.co.uk/2008/07/11/skyhook_jhl_40_boeing/ for a fuller story.
I thought most of the casualties were from people jumping -- the people who stayed with the wreckage as it settled to the ground were mostly ok.
-b.
True, airship crashes rarely involved the speeds or energy that are associated with airline crashes. In many airship accidents there are survivors (and more of them).
However, dying in an airship crash is not the only means of dying related to airship transportation. Line men (the guys that guided the airships to the mooring masts) would pull the airship into place (for the fine positioning work). They were accustomed to pulling the airship down and occasionally would be lifted off the ground (think big hops). Normally the added weight would pull the ship back down (assuming there were sufficient linemen)
In a few airship related deaths, linemen held to the line for too long (thinking it was going back down) when a sudden change in air pressure would literally pull them hundreds of feet into the air. Under such circumstances, the line men would have to hold onto the line or plummet to near-certain death. If the airship could not respond quickly enough, the line man would tire and drop to his death.
I'm not saying that this makes airship travel less safe than airplane travel, in fact it's much safer. Still different modes of transportation have their own associated risks. Comparing strict apples-to-apples isn't possible. I mean, how many people get kicked and die from their cars (as opposed to horses)?
Airships really don't work well in inclement weather, and many crashes were at least in part caused by unexpected bad weather (even the Hindenburg). The thing that makes revisiting airships in the modern era potentially interesting is that we now have very good Doppler radar, weather satellites, etc. So, it shouldn't be that hard to fly around bad weather in many places.
Thats the one of the rubs of airships. They can't go all that high compared to a jetliner without sacrificing huge chunks of lift capacity or using a aerodynamic lifting . So your stuck "below" the weather as it were. Also even at 40,000 feet theres plenty of turbulence as some frequent fliers will tell you.
If information wants to be free, why does my internet connection cost so much?