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Comment Re:The technical problems with this are immense. (Score 4, Interesting) 346

To every upvoted point, there has to be a counterpoint.

Sure jet fuel has a higher energy density, but that isn't the end all to the problem. You also have energy efficiency, which to my knowledge is pretty terrible on jet or turbo prop engines. I've been flying LiPo/Brushless RC aircraft for a while now, and in the right conditions your power efficiency comes right on par there with gas (minus any of the issues with ICE engines) In even better conditions, an electric plane can "recharge" batteries on descent.

There's a brand of starter electric planes called "Parkzone" One model (F-27 Stryker Brushed) was a particular favorite of mine. I went to a Gforce Lan event at Fort Mason, and on a lull between matches I flew it out in the heavy winds of the big green lawn. I kept that thing up there for 3 hours on a NiCd battery (usually only went for 15 minutes) I just sort of hovered it, more like "sailed" it and the motor just kept recharging the battery.

You can't really put jet fuel back in the tank like that. All sorts of crazy tricks you can do with electric though.

Comment Re:Remember the NASA Wind Turbines? (Score 1) 189

Current blades are trucked in one piece (per blade) which is impressive to see. Three of them were parked on I-5 outside of Patterson, California a few months ago. There are a lot of net videos and photos which convey the scale.

Even at the current size they can't get through many highway interchanges and local intersections. The larger ones won't be able to ship in one piece at all.

Comment Remember the NASA Wind Turbines? (Score 4, Interesting) 189

NASA Wind Turbines approached this scale in the '80's. Unfortunately, this was a previously-unexplored area of aerodynamics for NASA, and they had mechanical stress and noise problems (including subsonics) and were all demolished. I think there was one near Vallejo, CA being taken down when I got to Pixar in '87, and one in Boone, NC, which famously rattled windows and doors.

The art has since improved. I took a ride to the top of the turbine at Grouse Mountain, that was fun! That's the only one I have heard of where you can actually get to see it from the top.

Comment Starting out with the wrong assumptions (Score 2) 165

This is starting out with the wrong assumptions.

Design a brick system that can be produced with 3-D printers, and will hold together when fabricated within the tolerances of an SLA printer. Forget FDM, it's too low precision and SLA is already achieving an equal or lower cost of manufacture compared with FDM.

LEGO is manufactured to astonishingly high precision, but I am not convinced that this is the only way to make a brick system.

Comment Re:Side Effects (Score 3, Informative) 46

I have a friend with Friedrich's Ataxia, and CRISPR is one of the silver bullets she's praying for. FA cripples then kills you: wheel chair by 25, dead by 40 is often the case (it hardens the heart so it can't pump). While CRISPR has some unknowns and risks, having FA is a certainty. FA affects a single gene pair, so if you can replace either side of that gene, you have solved the problem, the mitochondria will start producing frataxin again, and the nerves will stop being slowly destroyed.

There are no treatments and since it is so rare (1 in 50,000 have it in the US, 1 in 30k in Europe, almost no one in Africa or Asia), few are investing in finding a cure or treatment. FA isn't the only orphan disorder like this. So yes, I'm quite happy to see CRISPR move forward.

Comment Re:No (Score 2) 270

You forgot margin. They have incredible margin on their products. Their concern is total profit, not units sold. They could easily drop their prices in other markets to keep market share, but the net profit to them might be lower. It isn't like iPhones prices are anything relative to their cost. Their price is based on what people will pay.

Comment Re:No comparison (Score 1) 132

Blue Origin will eventually have a two-stage rocket that can reach orbit (although they are planning on a much smaller payload than SpaceX for their first iteration). When the booster of that rocket lands without damage, they will duplicate what SpaceX has recently done, although in smaller scale.

Blue Origin to SpaceX at present is a sort of bicycle-to-automobile comparison if you account for the tremendous difference in energy and the application. So, I think there really is an intrinsic difference between the two of them.

If you want to say there's no intrinsic difference, then we need to look at Orbital's Stargazer and Pegasus, which have been carrying small payloads to orbit for years, and there's only been one Stargazer all of that time so there is no question that it's reusable. The only difference is that Stargazer lands horizontally.

We can then look at the B-52 and X-15 combination, in which both stages were reusable, a human was the payload, and we're going back to the late 1950's.

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