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Comment Re:Of course it is. (Score 5, Informative) 286

I did my own checks to see how many US military missiles were used for space launch.

Two Mercury launches (the suborbital ones) occurred atop PGM-11 Redstone missiles, which were operated by the US Army. The remaining four used SM-65 Atlas missiles, which were operated by the US Air Force. They technically had a new designation, but the modifications were mostly additional safety measures, so the actual launch system was essentially Atlas.

All twelve Gemini launches used Titan II missiles, used by the US Air Force. Again, they had a separate designation, but adding abort systems and backup navigation systems doesn't really make it "not a missile".

Apollo, as you stated, used only Saturn I, IB and V rockets, which were never used for military purposes. However, the Saturn I/IB's first stage was derived from PGM-11 Redstone. Only Saturn V was completely free of military history. The same is true of ASTP and Skylab, since they reused Apollo launchers. This definitely doesn't fall under "atop US Army boosters", but you can't deny that there was some history there - mostly because the design of Saturn started before NASA or even NACA existed.

The Space Shuttle did not directly use any military components, but the design was informed by the capabilities of the military-industrial complex. Solid rockets had, by that point, become the obvious choice for nuclear missiles, so much of the American rocket industry retooled around solid rockets, and so the Shuttle used solid boosters for much of its power. And the US Air Force did plan to operate their own Shuttles, even building a launch site for them (Challenger convinced them to go with expendable launchers instead). But it can't reasonably be claimed the Shuttle itself was a military product.

Comment Re:after trying so many times, Romero realized.. (Score 2) 86

I'm not sure what relevance that has, because John Romero hasn't been involved with id since 1996. You are (likely accidentally) correct that Romero's gone back to nostalgia games, but that involves mobile sequels to the Dangerous Dave series, not Doom or Quake. Mostly because Zenimax owns id Software, which owns the trademarks to Doom, Quake and Wolfenstein.

Actually, none of the original id gang was involved with the Doom Reboot. Romero is off doing his thing, Carmack is at Oculus doing VR coding, Tom Hall is failing to get Kickstarted on new games, and Adrian is apparently running a resort, of all things.

Comment Re:What's the point? (Score 5, Insightful) 86

Doom is actually pretty different than modern shooters. Everyone right now is doing near-future sci-fi military conflicts. Doom may still be sci-fi, but it's got a different aesthetic - borrowing from Christian demonology and pseudo-medieval fantasy for the art, and heavy metal for the audio. I can actually think of very few other things that do that sort of mix, definitely very few games.

As for the gameplay, both the DooM 1/DooM ][ sort of shooter, and the Doom 3 sort of shooter, are pretty different from the modern standard. Classic DooMs were extremely fast, but had slow-moving projectiles that could be dodged, and had extremely nonlinear maps. Doom 3 was slower and more methodical, and much more linear, but made a decent attempt at making a good horror shooter (it didn't fully succeed, but it was at least a novel attempt. Some lessons could be taken from FEAR, which had the same goal but different methods, which brought it more success). Both of those are different from the modern ultra-linear, setpiece-focused level design, and the twitchy, aim-focused shooters that are practically just reaction tests.

The Doom Reboot seems to be going for the more classic style, which (if true, and if done competently) would make it significantly different from all the other shooters out there.

Comment Re:How is this newsworthy? (Score 1) 295

I did a check of firearms law in Canada. There are very, very few guns that are wholly illegal there:
Machine guns or any other fully-automatic firearm
Pistols with a barrel under four inches
Long guns with a modified barrel under 18 inches, or under 26 inches length overall
Handguns in .25 or .32 caliber
Various other weapons specifically prohibited

#1 is completely sensible. There is no practical use for automatic weapons outside of the military. Even police do not have an actual need for them. Now, the American model of civilian machine-gun ownership (register, inspect and tax the crap out of) seems to be working just fine, and I could even get behind a repeal of the Hughes Amendment, but on the whole, a blanket ban on automatic guns is not a problem.

#2 and #3 are debatable. The purpose is obvious - to prohibit guns that are used chiefly for criminal activity, which requires that they be readily concealable. Their limit on pistol sizes seems rather low - even some 1911s would not meet this, and those are pretty beefy handguns. And they did seem to recognize that carbines have practical use, so they sensibly banned only modified short-barreled rifles/shotguns. There's room to argue over the specific definitions, but this is at least a sensible law in pursuit of a sensible goal.

#4 seems very peculiar to me. Those are very weak pistol cartridges, not something I would use for self-defense. At the same time, I don't expect they would be very popular with criminals - although, perhaps their low power makes them easier to produce for cheap, and criminals tend to favor cheap guns. If you don't have to actually shoot someone (eg. a mugging), it doesn't matter how lethal it actually is. So I'm not going to judge this one either way until I can find out what the rationale behind it it.

#5 is eminently sensible. Whenever you have laws like this, covering technical aspects, you need to be able to both cover the cases you couldn't think of (like taser-dart projectiles), and hold back the law where it would overreach (US laws allow weapons to be exempted from NFA Title II restrictions, not sure if Canada has similar means). A quick glance at the list of guns banned by name did reveal some surprises (all Kalashnikov-pattern rifles?), but many of them were sensible (Barrett M82).

Also noteworthy are some guns that were specifically placed on the "Restricted" list instead of the "Prohibited" list. Namely, any semi-automatic variant of the AR-15 - which means, with a license that seems easier to obtain than a passport, you can own several guns that were banned in the United States, at least until the AWB expired.

There's also the Non-Restricted class, which contains most long guns, and AFAICT requires no license. Considering a shotgun is by far the best weapon for home defense, this seems like a pretty easy way to defend yourself legally with almost no hassle.

So in other words, it seems the government of Canada does indeed respect your right to bear arms. I actually found more to be concerned with in their laws on melee weapons, many of which were pointless or mystifying.

PS: With the rampant availability of guns just south of the border, I have a very hard time believing that criminals will have substantially better access once 3D printing becomes commonplace. I'm sure any serious crook who wants a gun has made a trip down south to buy one, then smuggled it in. And with the quality of current printed guns, by making 3D-printed guns plentiful you would probably take more stupid crooks off the street (and into the hospital) than you would enable to commit crimes.

Comment Re:How is this newsworthy? (Score 3, Interesting) 295

Well, which parts are "important"?

For someone trying to make an all-3d-printed gun (perhaps to prove or improve the technology), it's the barrel, chamber, firing pin, and so on, the functional bits that are placed under the most stress. For them, using metal, particularly finely-machined metal parts, quite defeats the purpose. The only parts they might even consider making out of metal would be the ones plastic is literally unable to do, like the firing pin or springs - and even then, they'd try to make it out of some simple, readily-available part you can find at Home Depot.

For someone trying to bypass firearms laws, the important part is whichever one is legally deemed the "firearm", usually the receiver. You can buy barrels, recoil springs, magazines, grips, sights, and all sorts of other fiddly bits as spare parts, which are legally no different than a spare tire for your car. If you designed a 3d-printed receiver that worked with existing spare parts, you've worked around those pesky laws. (I personally find that law, at least, to be quite reasonable, but some people seem to want to work around it as a matter of principle).

And of course, to the person who's actually interested in shooting guns, rather than writing angry comments about them on the internet, the important part is whatever breaks most readily on your particular gun and needs replacement. I expect historical firearms shooters would be quite interested in being able to print parts once considered disposable, or which frequently are damaged, like clips. Or better yet, print brass casings for all those guns whose cartridges are no longer produced. There are many, many guns in collections that can't be fired not because they are old or damaged, but because the ammunition is so scarce. (There are many more problems than just forming the brass, obviously, and I don't think 3D-printing is a particularly good solution for it, but maybe I'm wrong and 3D printing will eventually help).

Comment How can FTDI not figure out how to do it? (Score 1) 268

Seriously, if FTDI wants to use their drivers to push out counterfeits, there's ways to do that without pissing off your customers or doing something possibly illegal.

How about, if your driver detects it's not actual hardware, you just refuse to work? Pop up a message saying "This is not FTDI hardware. This driver is not compatible with this hardware." If you want to be nice, give them a click-through that says "we have no idea what this hardware actually does. We cannot guarantee that using this driver will not cause catastrophic problems, and by continuing you agree to hold FTDI blameless for any damages caused by this hardware" - and then treat it exactly the same way as your actual hardware.

As for the counterfeiters... is writing your own driver really that difficult? Hell, hack FTDI's driver to call it something else and use different device IDs, if you want to be lazy. I've read up on these counterfeits, they're actually more complex hardware than FTDI. They clearly don't lack for capability.

Comment Re:Mars Colonial Transporter (Score 1) 101

Huh? Sea level and vacuum performances are directly proportional, within only a small variation between propellants. Do you even understand why there's a difference between sea level and vacuum performance?

In theory, yes, they're directly proportional. In practice, almost all LH2 engines have nozzle geometry optimized for high-altitude/vacuum operation, even on the first stage. That's not intrinsic to the rocket chemistry but you can see how I remembered it as so.

In any case, point conceded. CH4 is closer to RP1 than LH2 in specific impulse. And I agree with your statements about LH2 for upper stages - the tankage mass there doesn't matter quite so much. But SpaceX is looking at a fuel for all stages, and LH2 tankage in a first stage, combined with the other weaknesses of LH2 for their specific mission, is just a bad idea.

No we could not do something that would be difficult on Earth "relatively easily" on Mars. We're not going to be sending freaking natural gas drilling rigs to Mars (Mars being a highly natural gas poor planet), nor are we even going to have the sort of detailed geological survey data we'd need to be able to do that for many decades. We consider it challenging to build a bloody shelter on Mars, and you want to set up a petrochemical industry?

Compared to the challenges of getting to Mars, and constructing suitable long-term shelter, yes, setting up a petrochemical industry is easy. I did say "relatively", and when you're talking about anything outside Earth, the difficulty you're measuring relative to goes way up.

And if there *are* deposits of light hydrocarbons on Mars, wouldn't that be easier to tap into than trying to synthesize it from water and CO2?

Comment Re:Mars Colonial Transporter (Score 1) 101

False. But don't just take my word for it, take CEA2's. Parameters: all chamber pressures set to identical 204.08, pi/pe set to give a constant 100:1 expansion ratio, mdot=2223.8 (same as the SSME). All fuels burned with LOX at a stoichiometric ratio. All chemicals at their boiling point except the RP1, which is set to 300K. RP1 simulated by dodecane.

Seriously, have you never looked at an ISP table before?

I have, in fact, looked at ISP tables, but I was going off memory. Apparently I remember it being a lot more efficient than it is - I think I was remembering sea-level efficiencies rather than vacuum.

Nope. As is typical, it made up about 7% of the shuttle ET's mass. Nowhere near comparable to such an ISP difference.

7% is not an insubstantial amount, particularly when Falcon's figures for "all non-propellant, non-payload mass" are down to 3-5%. (It might also be worthwhile to point out that the Shuttle ET insulation was not without its flaws, which were perhaps caused by overzealous trimming of mass.)

Nope, CH4 freezes solid at 90,7K (versus LOX boiling at 90,2K). And it becomes way too viscous as it approaches its freezing point. That doesn't mean that they can't share a common bulkhead, but it does complicate it for long-term storage (aka, Mars missions)

Fair point, but it does simplify things more than LH2+LOX would be, or even RP1+LOX if you found a way to synthesize kerosene on Mars.

This is pure fantasy. Mars's atmospheric concentration is 10ppb - in an atmosphere that's only 0,7% the pressure of Earth's to begin with. Earth's is 1700 ppb at two orders of magnitude higher pressure, and the concept of condensing methane out of the atmosphere at "rich spots" is ridiculous even here - where we have extremely detailed global surface-level data on where "rich spots" are. Lastly, as much as I'd love a detailed surface-level whole-planet geological resource survey of Mars, that's just not going to happen anytime remotely soon - if in our lifetimes at all.

I wasn't expecting to pull it out of the atmosphere. Many of the theories for where the methane is coming from imply the existence of stores of methane somewhere on Mars. If, for example, it were trapped in underground deposits, we could tap into it relatively easily.

Comment Re:Mars Colonial Transporter (Score 2) 101

CH4 has a specific impulse much closer to LH2 than RP1. CH4 is 1 carbon per 4 hydrogen atoms, RP1 is about 1 carbon per 2 hydrogen atoms.

At vehicle scale, CH4 might be even more efficient than LH2. LH2 is a deep cryogenic fuel - boiling point at 20K. The mass of insulation needed it pretty severe, particularly when you account for its low density. CH4 boils at a much, much more reasonable 110K, making it just barely thermally compatible with LOX at 90K - this is significant for interplanetary flights, where the temperatures of the fuel and oxidizer will eventually equalize without intervention. That's one reason most interplanetary probes use hydrazine for maneuvering once past Earth orbit - they can just regulate the entire spacecraft to one temperature, not worry about boiling their fuel. MCT will have to cool its propellant but at least it's not too cold, nor do they need to insulate one propellant from the other.

Also, natural methane has been detected on Mars. If we can determine the source, it may be possible to use it simply by condensing it, which will be even easier than producing LH2. Other planets/moons may be even easier.

Comment Known for a while (Score 4, Insightful) 174

SYSMark has been known to be not particularly representative of actual performance for quite some time. In particular, they seem weirdly sensitive to memory latency, way beyond its actual impact, yet they deliberately evade caching even in benchmarks measuring something where caching is normally useful. And they do seem to unreasonably penalize AMD chips, although I'm not sure if that's malice or simple incompetence.

The review sites I frequent tend to use PCMark for the general-overview synthetic benchmarks, along with some actual-program benchmarks (usually compression, crypto, and video encode). I of course prefer the latter - nobody runs synthetic benchmarks in production, it's always some actual application. The closer you can get to benchmarking that actual app, the better.

Comment Re:Ship landing? (Score 4, Informative) 115

Shuttle SRBs were never reflown as the same unit, but they were disassembled for parts to use on later boosters - which were a combination of new and refurbished parts from various flights. Several booster components (structural/aerodynamic parts, mainly) from STS-1 were still being flown on STS-135, the final mission.

I can't speak for the actual economics of the practice, but on paper it looks like it has several obvious advantages, particularly when, as a solid rocket, the largest and most complex component is consumed during flight.

Comment Re:Microsoft need to just get it (Score 1) 165

It's not the detachable per se that's the problem - it's the limited ability to customize and upgrade which I would want in a full-size laptop, and that is at odds with the need for compactness that a tablet needs. Oh, and also the simple physical size - a productivity laptop ought to be in the 15"-17" range, not 13", if only for the keyboard.

The Surface Book seems like a good convertible ultrabook. The sacrifices they made to make it good at certain things made it less suitable for other things. Nothing wrong with being a specialized product - in fact, what I'm interested in is also a specialized product.

Comment Re:Microsoft need to just get it (Score 2, Interesting) 165

I'm actually getting a Surface. (A used Surface Pro 2, but still specifically a Surface - I found a use case where Windows compatibility in a super-portable machine with a touchscreen is actually quite useful).

Microsoft is blatantly trying to be Apple, but they actually seem to be doing a better job of it than the modern Apple is. All their devices are reportedly solidly-built and well-specced (either high-end overall, or good specs for the price... yes, their high-end stuff is expensive, but at least it's actually high-end). The Surface Pros are quite popular with artists because they have really good pen digitizers, and work with full-bore art software. They make reasonable compromises - the battery life is as long as it can be while keeping a reasonable size, the performance is as good as it can be while keeping battery life usable. Even the Xbox One is okay. I'm never going to buy one, but I can see that it's good at what it's trying to be, and about half of what it's trying to be is good for some users.

Meanwhile, Apple is making phones too thin for the battery to last a full day, then making an ugly, misshapen battery case to fix it. Making pens that charge off a fixed port, and snap with a harsh enough glance. Making screen sizes that don't evenly scale from their old ones, while having no good way for applications to scale to unexpected sizes. Introducing a variety of models with no clear hierarchy of performance or size or cost. Pointless cosmetic customization, but one-size-fits-all capabilities.

I actually would like to see a straight-up laptop from Microsoft. Not a convertible, not an ultrabook, a laptop - because the other competitors in that market are doing a pretty pitiful job of it. Something like the old Macbook Pros (before they got anorexia-obsessed) mixed with the old ThinkPads - a solidly-built machine, easy to maintain and upgrade, with usable base specs and plenty of customization so you can get what you actually need. (I wouldn't automatically buy such a thing, but I *do* think Microsoft would probably do better than any company currently doing so).

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