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http://www.johnmcphee.com/deltoid.htm

The Deltoid Pumpkin Seed tells the fascinating story of the dream of a completely new aircraft, a hybrid of the airplane and the rigid airship--huge, wingless, moving slowly through the lower sky. It flies aerodynamically. It floats aerostatically. It carries bridges, buildings, fleets of trucks. It is a flying warehouse. It eliminates the need for roads, railroads, prepared harbors. Or so goes the dream. With an arching back and a deep belly, it looks like a tremendous pumpkin seed.

If you're interested in weight-reduced (helium-filled) lifting bodies, you should read about the Aereon 26, as chronicled in John McPhee's excellent book The Deltoid Pumpkin Seed. A fair amount of research and money has gone into this general area of design, with mixed results. And, as you say, a lot of people who research UFO's say it's possible that these are what the US Government is using for very high altitude, long-time-on-station rec. I've heard people claim that these are being used at 100,000 feet or thereabouts on US borders, although I'm marking these stories as only slightly more reliable than alien contact stories.

I've been watching for something like this since the New Yorker carried a series about hybrid airships when I was in grad school. Seems it was finally published as a book (1973): The Deltoid Pumpkin Seed

I guess it says something about the time it takes for new technology to get off the ground, so to speak.

Everyone thinks of the Hindenburg, but as the New Yorker article pointed out, there weren't many passenger aircraft in those days, and this was the first such crash caught on video, so it had a huge impact. These days, we have 10 times as many lost in a passenger jet crash and even if on video it has much less impact on the public at large.

I also worry about the amount of rainfall that would be lost if Bill Gates plan actually works. Believe it or not there are some useful aspects to a hurricane and more importantly tropical storms.

Hugely useful. Here in central North Carolina (NC), the ends of our summers (August - October) are hot and often very dry. We get thunderstorms now and again but for a nice steady, soaking rain we rely on a tropical storm or hurricane running up the coast or moving north through the Gulf of Mexico, breaking up over land and then sweeping east over us as the remnants get caught up in normal weather patterns.

Have a look at the paths of the storms in 2007. Notice how few approach NC? That was also the year of the worst drought in over 100 years. We didn't get those late summer storms to mitigate an abnormally dry year.

Compare that to the 2006 map and the 2008 map. Lots more rainfall for us.

whatcouldpossiblygowrong indeed. Read John McPhee's Control of Nature for some examples. The story of the defense of the harbor on Iceland's Heimaey is inspiring. The story of redirecting mudslides near LA is a cautionary tale. Similarly, the story of how the US Army Corps of Engineers tool control ("permanent" control from humanity's point of view, "temporary" control from Nature's) of the flow between the Mississippi and Atchafalaya. Before that, the river rose and fell and people accepted it because they had no choice. Afterwards, people complained that the water was too high, or too low, and probably too wet as well.

Control a hurricane? Even if I had a magic wand with which to do it, I'd say no thanks. I would not want to catch that tiger by the tail.

Right, because piracy was non-existent until recently when CNN started covering it.

"Pirates are only one of the challenges facing the Stella Lykes." - http://www.johnmcphee.com/looking.htm

A great book about the merchant marines BTW.

John McPhee's book The Control of Nature has a large section on Icelanders' attempts to divert lava flows from a town and harbor. It's a heck of a good read if disaster science turns you on.

http://www.johnmcphee.com/controlofnature.htm

1973

http://www.johnmcphee.com/bookshelf.htm

Case closed.

The idea of hybrid lighter than air lifting and an aerodynamic hull has been around for a while. In his 1963 book The Deltoid Pumpkin Seed essayist and journalist John McPhee covers the story the the Aereon, which was an early avitar of the dynalifter. There was a brief resurgence of interest in this aircraft design during the oil crisis in the 1970s. It now seems to be back once again now that oil has risen in price.

One of the things that those pushing this design may not be mentioning is that increasinly helium is both scarse and a strategic resource. Helium is actually "mined" from underground domes where it has been trapped (I assume formed from radioactive decay). If fleets of airships were helilum based, the price of helium would seen rise to the point where the airships were no longer cost effective. The alternative is hydrogen, but as the Hindenburg demonstrated, hydrogen has its own problems. These issues could be the reason that after over three decades this idea has not caught on.

This sounds similar to the Deltoid Pumkin Seed, another airplane/blimp hybrid. It was more of a helium-filled flying wing that was tested in the seventies.

The Deltoid Pumpkin Seed tells the fascinating story of the dream of a completely new aircraft, a hybrid of the airplane and the rigid airship--huge, wingless, moving slowly through the lower sky. It flies aerodynamically. It floats aerostatically. It carries bridges, buildings, fleets of trucks. It is a flying warehouse. It eliminates the need for roads, railroads, prepared harbors. Or so goes the dream. With an arching back and a deep belly, it looks like a tremendous pumpkin seed.

You can also read about Project Orion in John McPhee's book The Curve of Binding Energy . This book is mostly a long conversation between McPhee and Ted Taylor, (more) a physicist and ex- nuclear weopons engineer. In the early 70's Taylor becomes worried about how easy it is to build a fission bomb. Taylor and McPhee drive around and survey the security of nuclear materials while Taylor talks bomb theory and practice. The title comes from the curve on this page.

What it the buoyancy effect is just used as a freebie, and the large wing area also contributes to the lift significanty

Ah, you're talking about something like the deltoid pumpkin seed. Yeah, that's a valid possibility that I overlooked. (Posting in the middle of the night, what can I say.) Modern materials technology might make that design more feasible (although they did eventually get the prototype working).