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Comment Re:Yes, it could (Score 1) 238

I read somewhere that flying NYC to LA on a corporate jet costs about $30,000 - not sure if that is total or per passenger. So that's something close to the cost target. If they can get you there in 1/2 the time, is it worth $60,000? These are the numbers they're probably working with. Note that Virgin Galactic has flights booked solid for seven years worth of flights at $200,000 each, and those flights are just up and down for entertainment.

Comment Re:Yes, it could (Score 1) 238

The major US air carriers have definitely gotten out of their repeating-bankruptcy spiral and are registering record profits these days. Through mergers and other tactics, they have eliminated almost all of the low cost alternatives, and at nearly all major airports the majority of the gates and flights are 'owned' by one or two airlines, eliminating effective competition. Note that they raised prices when fuel prices went up, and kept them their afterwards, and added baggage fees, etc. - soon they will be charging extra for the right to breathe actual air, I'm sure.

Comment Re:Concorde 2.0 (Score 1) 238

It's quite possible that Virgin Galactic, or some other entity working on suborbital flight systems, could make this whole idea moot. Rather than worry about sonic booms, get completely out of the atmosphere. Think of it as a two-stage passenger-carrying intermediate range ballistic missile, probably with horizontal take off and certainly horizontal landing. This system could provide 3000 mile / 5000 km flights at Mach 5, 10 or more, depending on where the economic sweet spot is, with near-zero concerns for sonic booms. I have heard that Virgin is considering this as a future service. Of course, if the Skylon project pans out, it's doable with one stage.

Comment Re:Concorde 2.0 (Score 1) 238

I get almost 28 MPG on long trips at 67 MPH, about 25 MPG at 75 MPH. That cubic drag coefficient really starts to hurt.

IIRC the reason golf balls have those little dimples is that they cause little 'air ball bearings', which both increase the distance and reduce turbulence, which reduces the wobble and increases accuracy.

Comment Re:Concorde 2.0 (Score 1) 238

Or just throw a wall of bullets in front of it. I've read that during the VietNam war, to avoid ground-to-air missiles the US fighters often flew low to the ground - they were so fast that by the time you saw one coming over the ridge it was too late to shoot at it from the ground. But the North Viets figured out that they could have spotters on radio or telephone or whatever, and when one was spotted in the next valley over, everyone in this valley would just start shooting into the air. Some of those bullets got in the way of the fighter, and they did bring some down that way. Or so I've heard.

In theory, it's quite possible. Supersonic planes are going at bullet speed, so a stationary object has the necessary relative velocity to act like a bullet.

Comment Re:Concorde 2.0 (Score 1) 238

IMHO the fundamental issue is the inexorably increasing cost of speed - doesn't drag increase as the cube of velocity, all other things being equal? You can make things more and more pointy, but that has decreasing returns.

Maybe (my idea recently) you could push very high pressure air out the tip of the plane to insulate against the heat build up (but pressurizing that air would also cause heating ...) Maybe with such an analogue of supercavitation you could reduce the drag by 'hiding' the vehicle behind the supersonic wedge created at the front?

Comment Re:Concorde 2.0 (Score 1) 238

That's mostly wrong. The US SST was well along when the issue of sonic booms was raised, not as an anti-EU competitive measure but because there was existing law already on the books that banned supersonic flight over the continental US, at _any_ elevation IIRC, except over certain (very large) military reservations. One of the reasons the SST was cancelled was because lobbying by Boeing et al failed to overturn that sanction, making it impossible to run SSTs from NYC to LA, which was the primary target market. Without overland flights there was no way for any supersonic airliner (or any airliner for that matter) to make money. The Concorde development was continued in the face of that for purely national pride and EU cooperation reasons - basically by then its completion and operation were a political necessity even though nobody thought it could make money. Politicians in UK and France would _both_ have to had the guts to put thousands of workers out of work, at a time when the unions basically ran both countries.

Comment Re:Drone It (Score 1) 843

It's possibly worth noting that according to some thing I read a year or two ago, biologists who knew such things believed that the reason bears died out in Africa lo these many years ago is that they are omnivores, and designed to do reasonably well at many things but are not optimized for any of them. But Africa gradually became populated by specialists who did _one thing_ very well, and the bears were gradually out-competed at everything.

Comment Re:Hm (Score 1) 385

That made me think - you could actually incorporate xCoin, so folks whose postings are popular would actually get paid a tiny amount, and everyone pays a tiny amount to post. I'm not sure of how this would exactly work, but it's certainly possible. Maybe it costs $1/month to join, you get 1000 up/down votes per month. So if someone's posting got 3000 votes (either up or down), their account would accrue $3 less whatever the website's overhead is ($.50 for purposes of argument), netting $2.50. It's not a zillion dollars, but could be fun. Maybe only get paid 1/2 for a down vote, but IMHO downvotes should get something, as it still represents traffic and interest. Maybe have a threshold - no pay for less than 10 votes.

Kinda like the 'ante' in poker? Such a site might be successful without advertising. This is a good enough idea that I'm proposing it to some friends.

Comment Re:Build colonies on Earth (Score 1) 256

Indeed, I was playing fast and loose with the definition of resource, but I think in this case it can be considered as such. ;) Too much sun can still be a bad thing, especially if it's evaporating all the water, and the energy absorbed and reflected by the solar panels will reduce the temperature underneath. So let's assume that the solar panels are 30 feet above ground and block 30%-70% of the light. (There is some percentage that optimizes the total system of electrical power + plant production, but I don't know what it is.) We put greenhouses underneath, mainly to contain the moisture - we're going to have to irrigate so a closed system (with a floor) would be best to prevent the water from disappearing into the ground as well. Most greenhouses have to have fans and shade systems to prevent overheating on even nominally warm days.

So we use some of the power to run a desalination plant to provide the water, and the rest of the energy we use in-country or export. Given a 100 square mile facility, underneath we've just added almost 100 square miles of quality agriculture in a country that has very limited resources, and we've begun to replace the oil-export economy with a real production economy that actually employs people. (I'll note that we also have to figure out what to do with the higher-salinity water - that's a potential eco problem.)

This system could be expanded gradually, even possibly to thousands of square miles. Solar power costs are already getting close to competitive with thermal power plants, and by synergizing the real estate this way it could make a real difference to the folks in North Africa, for instance. It also has a social benefit, as it employs workers.

Many of the breadbaskets are in higher latitudes - India and central Africa are the exceptions - and receive much less light. A Sahara growing facility has more sunlight than is really necessary for most plants.

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