Dynafilter!

January 5, 2006 8:42 AM

Dynalifter! In a cornfield in Ohio, a pair of IT men live the dream as their 150-foot prototype dirigible (which combines airfoil lifting surfaces with a lighter-than-air central hull) readied for a test flight to come this spring.
posted by mwhybark (27 comments total)

Weren't they afraid of the children of the corn?

Otherwise, this is pretty cool. I always like it when people just decide to build crazy shit.
posted by Astro Zombie at 8:58 AM on January 5, 2006

Think I first read "The Deltoid Pumpkin Seed" in the late 70s. I followed with interest (and a bit of investment...) several attempted resurgences of the airship in the late '90s.

I wish them luck, it's a great concept and a cool project- but I think the time of the airship is past. However, if they made a large one a luxury transport I'd love to ride in it...
posted by JB71 at 9:13 AM on January 5, 2006

I dunno. I suspect these two may just be full of hot air...





*ba dum bump*
posted by stenseng at 9:15 AM on January 5, 2006

Airships are doomed (if they are doomed) more for reasons of PR than anything else. Hydrogen can be used safely, but the public still thinks that's what destroyed the Hindenburg.

Re. Hindenburg, it's now widely believed that the explosion was caused by ignition of the aluminum-based doping compound on the airship's skin. Experiments with apporximations of the Zeppelin forumula have shown that it's dramatically flammable. The Zeppelins were actually very well designed for Hydrogen safety, and a ship like this could be, too.
posted by lodurr at 9:19 AM on January 5, 2006

Oh the Huge Manatee?
posted by blue_beetle at 9:22 AM on January 5, 2006

Blimps are a potentially very interesting cargo market. In terms of kg-cost per kilometer, they fit nicely between air and rail, in the same area as trucking. Combined with the fact that they get more economically feasable as they get bigger, it's possible that rail-sized cargo volumes could go economically by air.
posted by bonehead at 9:23 AM on January 5, 2006

... and then there's the potential market for aerostats as satellite replacements.
posted by lodurr at 9:25 AM on January 5, 2006

Oh the humanity!
posted by HTuttle at 9:34 AM on January 5, 2006

I don't think the hindenburg is really that big of a deal PR wise anymore. It was almost 80 years ago. Nobody remembers, and people understand that technology today is diffrent then it was in the 1930s.
posted by delmoi at 9:55 AM on January 5, 2006

Also, this one is filled with helium anyway.
posted by delmoi at 9:55 AM on January 5, 2006

Hmm, I looked up the Hindenburg entry on wikipedia and found this:

Further, the recent technical papers [1] point out that even if the ship had been coated with typical rocket fuel (as is often stated in the press), it would have taken many hours to burn — not the 34 seconds that it actually took.

So it appears, at least on wikipedia that it's nowhere from resolved that the ship burned because of the paint.
posted by delmoi at 10:05 AM on January 5, 2006

The same freight lifting thing is being tried out by a vowel-challenged German company, Zeppelin Luftschifftechnik. There's also JP Airspace, which is attempting to use helium vehicles to get into space safely. Zepplins are extremely appealing to engineers when you consider that everything else has to expend massive amounts of energy just to stay airborne- they are as close as we can get to anti-gravity. Still, the idea is an old one and commercial viability has always been just out of reach...

lodurr: Germany used hydrogen in its Hindenberg era zepplins because the U.S. would not give them helium, and helium resources are almost exclusively concentrated in the United States. For the dynalifter concept and all dirigibles now adays, Helium (an inert gas) is used.
posted by efbrazil at 10:14 AM on January 5, 2006

Oops- I goofed the German company link- they're the historical zepplin company. Here's details of the ill fated cargolifter project that I was thinking of in Germany.
posted by efbrazil at 10:22 AM on January 5, 2006

There is a good article in Scientific America (Nov. 1999) if you can get your hands on it.


Airships


Also, go to LOC and type airship into the search and there are some panorams from airships and of airships.
posted by fluffycreature at 10:37 AM on January 5, 2006

Helium (an inert gas) is used.

Helium is not inflammable, is what you probably meant. It is not an inert gas, as it will react with certain compounds under the right conditions.
posted by nlindstrom at 11:01 AM on January 5, 2006

I rode in a blimp once! It was the Fuji blimp (the only one at the time; maybe now there are more), and I was in it because I was writing a newspaper article about the blimp management company.
We took a short trip from Westchester County Airport in NY to the sky over Mahwah, NJ, to hover over a third-tier women's tennis tournament. (There was a TV camera and a cameraman named Len on board. He gave me a sandwich.)
It was totally cool. I hung my head out the window and snapped photos (which didn't come out). The crew was laid-back and seemed sort of amused at the whole thing.
posted by Dr. Wu at 11:21 AM on January 5, 2006

delmoi: Hmm, I looked up the Hindenburg entry on wikipedia and found this:

Further, the recent technical papers [1] point out that even if the ship had been coated with typical rocket fuel (as is often stated in the press), it would have taken many hours to burn — not the 34 seconds that it actually took.

So it appears, at least on wikipedia that it's nowhere from resolved that the ship burned because of the paint.

That's an interesting take. I watched a "Secrets of the Dead" episode where they extrapolated something quite different based on experiements done with an approximation of the actual doping materials. I don't have a link to a video (the annoying flash-based site for the show is here), but it was quite impressive as I recall.

I think the chemical reaction argument is a red herring. As I recall most of the "flammable fabric" stuff that I've seen or read, the argument is that ignition was due to a static spark, not a chemical reaction, and that rapid propagation was exacerbated by heat and the orientation of the fabric.

Another point made by the "flammable fabric" krew is notably not addressed in the Wikipedia article: That hydrogen won't combust in the absence of oxygen. So there had to be something that was causing the fire to propagate within the structure. At the same time, the fire propagation within the structure had to happen in such a way as to be non-explosive. (The fire clearly propagates over the intact outer skin of the craft at a very rapid rate. Presumably its rate of spread could be exacerbated by burning hydrogen.)

Another interesting point: As I read the paper cited in the Wikipedia article, I note that they tested propagation by lighting the fabric on a horizontal surface. I flash back to a film I saw years ago that compared flammability of materials when burned horizontally and vertically. Imaging lighting a match and holding it with the head horizontally; then, imagine holding it with the head pointed downward. Which way will it burn faster?

What's obvious to me is that there isn't a single cause. The ship would not have failed catastrophically in that way if all factors hadn't been present.

As for why I would defent hydrogen as opposed to helium, just consider the lifting capability of one versus the other. Then consider that one is readily available, and the other is expensive and has to be mined. (Fortunately, I've been told, we have most of the world's helium reserves...)
posted by lodurr at 11:47 AM on January 5, 2006

Looks like a cool little thing, but I'd be concerned about handling in rough weather. It presents such a big, light profile...
posted by BlackLeotardFront at 11:55 AM on January 5, 2006

Pretty cool.
posted by Smedleyman at 12:05 PM on January 5, 2006

Zeppelins and such are pretty cool, but I recently decided that what would be cooler are nuclear-powered aircraft, and airbases like the British one in Sky Captain and the World of Tomorrow. Using the power of the atom, they could stay up for years at a time.
posted by TheOnlyCoolTim at 1:21 PM on January 5, 2006

Sounds to me like lighter-than-air craft work great (as long as the wind doesn't blow).
posted by squalor at 2:12 PM on January 5, 2006

Ha! I'd like to see two guys do this in a cramped apartment in Midtown Manhattan. Take that, city dwellers!

The science nerd in me has his fingers crossed.
posted by Eideteker at 2:36 PM on January 5, 2006

What would be the benefit of nuclear powered flying cities, aside from the cool factor?

It's not like the flying city could travel around the world like an ocean liner. Imagine an influx of 500,000 tourists in a single day...
posted by parallax7d at 4:15 PM on January 5, 2006

I believe the cool factor is sufficient. Or, once we've filled up all the space on the ground with regular cities, there's really no place else to go.

But my initial suggestion was actually airbases of a couple thouseand people max, basically flying aircraft carriers, not aircities.

I remember the concept was also explored in Disney's TaleSpin, by a monkey of some sort with a flying gas station.
posted by TheOnlyCoolTim at 5:49 PM on January 5, 2006

The discovery that here in Kansas the natural gas contained helium makes for a good story.
posted by sp dinsmoor at 6:16 PM on January 5, 2006

Heck, we can't even get floating cities produced - I have no hope for flying ones. :(
posted by JB71 at 6:34 AM on January 6, 2006

The cargolifter hangar was converted into the "Tropical Iceland Resort" after the project collapsed. Not quite a city, but still pretty cool.
posted by efbrazil at 11:59 AM on January 6, 2006