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Comment Re:Good (Score 1) 319

2. Hypersonic travel becomes practical and you can fly anywhere in the world in ~5 hours.

To make hypersonic travel practical, they have to make passenger-mile per gallon-of-fuel close to present day passenger airliners.

That's why supersonic airliners like the Concorde really failed. The Concorde was never economical compared to its subsonic competition and had to rely on government subsidies. The crash of flight 4590 was just the straw that broke the camel's back.

Hypersonic engines either have to be more efficient than the supersonic engines on the Concorde and carry the same number of passengers (unlikely) or the airplane must carry more passengers than the Concorde to make up for its inefficiency (also unlikely).

Having said all that, there may be niche markets for small hypersonic business jets or small cargo planes (FedEx's new slogan, "When it absolutely, positively has to be halfway around the world... TODAY!").

Comment Re:My Investigation (Score 1) 92

I'm a developer who has wanted to break away from enterprise in this sort of game dev, I would throw money at this product to give it a chance had it not been for all the strange things about it.

You know you could just learn Android and Android game programming and not worry about the Ouya.

The developer's tools are free and there are tons of tutorials on the web and YouTube.

And it's not like there aren't a few hundred brands of Android smartphones, tablets and, yes, even media boxes.

Comment Re:Seems like a tremendous waste (Score 1) 197

The F1 was designed on blackboards and drafting tables. A "modern" F1 is only going to be similar in size - it'd have to be a clean sheet design, the facilities that built the F1 are long gone at this point. Why even study redesigning the F1? This seems like a tremendous waste. Of course it's going to be a clean sheet, computer drafted design.

Some designs stand the test of time.

The RL-10 is another Apollo era rocket engine that's still in production.

Comment Re:SpaceX will fly circles aroudn them (Score 1) 103

I'm surprised they overspec'd a NEO capsule like that. Unless the plan all along is its a deep space capsule.

Not really. The Dragon capsule (and heat shield) is designed to be reusable.

It's thicker and stronger so they only have to replace the heat shield every 5, 10, 20 or whatever number of flights.

Comment Re:SpaceX will fly circles aroudn them (Score 4, Informative) 103

There are also certain mission trajectory issues. One whacked out Apollo emergency return trajectory had the capsule entering pretty steep at damn near escape velocity which is an immensely higher thermal load than merely controlled descent from low earth orbit. You could baby the trajectory of a deep space capsule and just declare some "survivable with a massive shield" abort orbits to be unsurvivable. But generally a deep space heat shield is going to be much heavier and higher speed rated than a NEO heat shield.

One thing you don't have to worry about is the heat shield.

It's made of PICA-X, a highly-advanced abrative heat shield material developed by SpaceX based on PICA, a heat shield material developed by NASA in the '90s for the Stardust return capsule, "the fastest man-made object ever to reenter Earth's atmosphere (12.4 km/s or 28,000 mph at 135 km altitude)."

According to Elon Musk:

"It's actually the most powerful stuff known to man. Dragon is capable of re-entering from a lunar velocity, or even a Mars velocity with the heat shield that it has."

Comment Re:LOL (Score 1) 1165

Hey idiots...instead of making NEW laws for firearms, how about ENFORCING the current ones?

Politicians don't get elected by enforcing laws, they get elected by enacting laws and then crowing about them when reelection comes around.

Comment Re:So how do the airlines handle it? (Score 1) 169

LockMart and Boeing and the ULA make their money selling launches to private and government clients too. (McDonnell Douglas was bought out by Boeing nearly fifteen years ago.) So they also have every incentive to make their boosters as reliable as possible. SpaceX is no different than those companies.

Seriously?

LockMart and Boeing are huge, huge, bureaucratic companies with dozens of divisions and thousands of products and tens of thousands of customers.

SpaceX is a small, highly-focused and driven start-up company with two products; the Falcon booster and the Dragon capsule. Where the CEO, Elon Musk, probably knows all the engineers by their first names and probably walks the floor on a regular basis.

The CEOs of LockMart and Boeing are probably lucky to know the names of all their division managers without a cheatsheet.

And you see no difference between them.

Again, SpaceX is no different from the others - their boosters don't need to be any more reliable than their contract requirements require either.

Except the Falcon booster was designed from the beginning to be reusable, which means it was designed to be extra reliable. Unlike a disposable booster like the Atlas.

(I.E. you can damn well bet their launch contracts do not accept full responsibility for anything but "attempting" a launch. They'd be fools otherwise.)

SpaceX has an "Indefinite Delivery/Indefinite Quantity" (IDIQ) contract with NASA. My understanding (and I could be wrong) is that that calls for deliveries, not attempts, not launches per se. Of course each delivery is a launch so the difference is partly semantic.

They're all pretty much ignorant of how little experience we actually have designing boosters and how much it costs to add each decimal place of reliability.

That's the NASA mentality, just build it "good enough" and then inspect, inspect, inspect for reliability.

SpaceX is approaching the problem from the design perspective, like the airlines. Design for reliability, like an airliner, and then perform regular, scheduled maintenance.

I understand the concept is foreign to traditionalists.

Comment Re:So how do the airlines handle it? (Score 2) 169

That, and failure rate for civil aviation is several orders of magnitude lower.

Now, yes.

But what about, for example, SpaceX Falcon boosters which are designed from the beginning for reliability and reuse? Instead of boosters which are designed merely "good enough" because they're only used once.

SpaceX has a much different mindset than Lockheed Martin or McDonnell Douglas. They plan on making money selling launches to private and government clients. They have a strong incentive to make their boosters as reliable as possible, and from everything I've heard, that's exactly what they're doing. Elon Musk's reputation is on the line with every launch.

Unlike Lockheed Martin, McDonnell Douglas, et al who only need to design and build their boosters "good enough" to meet their contract requirements. Who's personal reputation is on the line if an Atlas booster fails?

I don't see any reason why, with proper design, boosters shouldn't be as reliable, or almost as reliable, as airliners.

Comment So how do the airlines handle it? (Score 2) 169

Clearly the airlines fly many, many more flights over much more populated areas than commercial space companies plan to over the next decade or longer and they are still in operation. So what is their insurance coverage strategy?

I'm guessing that the biggest difference is that the actuary statistics are well established for the airline industry, while they're limited for the commercial space industry.

Perhaps in that case it would be reasonable for the government to continue to indemify the commercial space industry until there is sufficient data for commercial insurance companies to feel comfortable selling coverage.

Comment Contracting through a Canadian or American agency (Score 1) 402

Quite a while ago I read the answer to a simliar question about finding work in Europe.

Most Europian countries have strict laws about hiring non-citizens for most jobs. He got around that by finding contract work through an American contracting agency.

The benefits are that since contract work is inherently temporary there were no problems with non-citizen status. The contract agency would bill the company directly and deposit his paycheck in an American bank so he usually didn't even have to pay local taxes. And the IRS has (had?) generous tax deductions for Americans who spend over some large number of days out of the country.

The downside is that he moved around quite a bit, whether by choice or job requirements I couldn't say.

I also don't know if there are any agencies in Canada or America that contract with companies in China.

Comment Re:Border crossing (Score 1) 298

Before going back across the border, save any work back to your remote server and delete the SCP client, browser, Truecrypt, and the encrypted file. If you're really paranoid, reinstall the OS from the rescue partition.

Remember, deleting files or even reinstalling the OS doesn't remove the actual data from the disk. Use a utility that overwrites the unused fisk surface with at least random data or preferably to DoD data destruction standards (and run it from a thumb drive if you want to be extra safe).

Overwriting with two or three passes of random data is probably enough. Recovering overwritten data is possible but becomes increasing difficult and overwritting to DoD standards takes a long time, but reasonable people may differ.

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