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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."
They must not read /.
Helium Crisis Approaching, slashdot earlier this year.
A Helium Shortage?, Wired eight years ago.
Almost all the large airships that were built in the past crashed, Google can tell you that (I removed Hindenburg from the list because that was a fire, not a crash). As a matter of fact, I think they ALL crashed, except but one, that is I think I once read about a large airship that was retired due to old age, but I'm not sure.
Being fragile is an intrinsic condition of a structure that must be very large, yet very lightweight. Heavier-than-air craft are much sturdier, just because they are, well, they are heavier.
We certainly do. The one for aerostatically-suspended vehicles is "Fly in nice weather".
An airplane suspends itself entirely with aerodynamic force, which the pilot can manipulate to a high degree and on a very short time scale. Hit a downward bump, pull back a little on the stick, lift increases, flight path remains nearly constant.
An airship suspends itself principally with an aerostatic force which can't be modified very much, and maintains the desired flight path with relatively small aerodynamic forces which are manipulated in the same way as an airplane. The latter forces just don't have enough range to deal with serious turbulence.
Besides making maneuvering difficult or impossible, turbulence presents another threat: stress. While the aerodynamic forces the pilot can apply are small, the ones a thunderstorm can apply are not. Aerodynamic forces depend on the surface area of an object, and the surface area of an airship is huge. Big forces, big stresses on a necessarily lightweight structure.
rj
Mankind does Life Threating actions everyday; Flying Aircraft is but one dangerous occupation. And when the weather is rough, good pilots change flight plans. One benefit would be that Truck Jackings would go down, (a bad use of words here...). But what is the cost per ton by the Consignee? What is the average ground speed for cargo delivery. What are the Logistics of this Grand Design? I know this; "Point to Point Delivery" would open up our congested Freeways, that's cool.
Just a thought, but what about a "Sport Light Aircraft Blimp"? Just please don't call this Aircraft an "Icarus".
Your ideal newspaper would read "2020: The USA successfully set up their base mars yesterday after 12 years of work on the project"?
That actually sounds awesome. No more bs news flogging vaporware stories anymore...
Did you even RTFA? Helium is a byproduct of oil extraction. If the oil dries up, no more helium, either. Unless you think transmuting elements is something that can be economically done on a large scale.
Can you be Even More Awesome?!
Ironically, when the Hindenburg (which was among a tiny minority of airships that actually crashed) wrecked, a scant few people were killed, a couple injured, and the rest survived. When an airliner crashes... well, survival chances are... not quite as good. So lets get it right, if an airliner pilot wrecks the plane, you're fairly likely to DIE. If a zeppelin or something to that effect crashes, you've got a fairly good chance to tell a "wow look at me" story about your "shipwreck adventure" which is probably why the Hindenburg got such note...
Do your own research on the subject, but they actually were safer than airplanes (and significantly more economic). Either way, hopefully you'll dig up your own research on the subject.
" What luck for rulers that men do not think" - Adolf Hitler
How cool would it be to have a fusion-reactor-driven zeppelin that replenishes its own Helium?
OTOH, I'd imagine people would object to the possibility of a fusion reactor dropping on their house in case of an accident.
To be, or not to be: isn't that quite logical, Slashdot Beta?
this thing has a lift capacity of 40 tonnes.
to achieve that requires:
40 short tonnes is 36287389.6 grams
each gram of helium displaces about 29 grams of air, so this requires lift equaivalent to:
14.5 thousand kilograms of helium
Now imagine you fly this somewhere. If you unload the cargo, the tiedowns have to hold 40 tonnes of pull. So you can't just teather this ting like a balloon on one end like they used to do. The needle on the empire state building was an air ship dock and all the pictures show the airships teathered oriented horizontally not point up.
So how do they do this. You might think well they could cantaleaver an moveable weight to hold the back down. But then you have to strengthen the middle to support this tension without bending plus you have to drag the weight. Worse yet if the teather erer came loose you'd suddenly have 40 tonnes of lift shooting you towards the moon like a watermelon seed.
The best Idea I can think of is you could pump water onto it at the same time you remove the cargo to keep it all neutral.
But this means no dead heading. No matter where you go the cargo is always exactly 40 tonnes. otherwise you'd have to waste 14 thousand kilograms of helium on every trip.
by the way, for comparison the cargo capactiy of the biggest 747 is 53 tonnes. ( and a DC-10 has 50% more capacity)
It's not clear to me if the cargo volume of a 747 or a blimp is bigger. On the one hand the blimp has a lot of excess lift capacity. But still if the size of the cargo area gets bigger the weight does go up.
Some drink at the fountain of knowledge. Others just gargle.
Having taken classes from Prof. Breidenthal, I can tell you that, more than likely, his quotes are absurdly dry understatements. Also, I can tell you that he's right. It should be a rule of the internet: When Professor Breidenthal and a random internet commenter disagree, Professor Breidenthal is correct. Corollary 1: A belligerent noob will have no idea how badly he has been owned by Professor Breidenthal's absurdly dry understatements. Corollary 2: If Professor Breidenthal refrains from ownage, then the noob is open-minded and shows potential. That guy is smart, and his classes were hard. He always tried to craft tests so that the average score was 50%, to "maximize the dynamic range." (Separate the wheat from the chaff, I gathered.)
I think Stephenson created dirigibles built from nanotubes that "stored"(?) a vacuum. No hydrogen or helium needed.
It's all in the Young Lady's Illustrated Primer.
It is interesting to take a good long look at the news footage of the crash. If you do, you'd notice that all the hydrogen burned off in the first couple of seconds, and by the time the Hindenburg actually hit the ground, it had all gone.
The fire and most casualties were from the combustion of the diesel fuel and other combustible materials in the structure, not from the hydrogen itself.
I would like them to hold a Private Pilot's night at Six Flags -- to get on the roller coasters you have to show a pilot's certificate. I would like for just one time in my life ride the coasters with a bunch of people who appreciate the fine points of their design and won't yell, scream, raise their hands and go "woo" and just plain STFU and enjoy the ride.