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Comment: Re:Drone It (Score 1) 701 701

The B-52 requires complete air superiority in the area that it operates because it can't hide from radar except by jamming, so just building a new version wouldn't really work. The B-1 has speed on its side (thought not as much as the original specs) and the B-2 has stealth. The tentatively named B-3 is supposed to replace all of the heavy bombers, though the B-2 will probably stick around for a few decades. That's a reasonable goal, unlike that of the F-35.

It's supposed to use mostly existing technologies instead of planning for advances as happened with (and expanded the cost and schedule of) the B-2, F-22, and F-35. Whether they can actually do that is a giant question mark, but the Air Force is allegedly targeting $500 million to $600 million per plane as the final cost.

Comment: Re:Drone It (Score 1) 701 701

The Harrier can't meaningfully hover with a full weapons load, either, and it really only takes off vertically at air shows. STOVL is short for "short takeoff, vertical landing". They've been planning ramped takeoffs and vertical landings at sea from the beginning, just like the Harrier uses.

I'm not fond of the F-35, but don't ascribe features to its (at least as problematic) predecessor that aren't there.

Comment: Re:Drone It (Score 1) 701 701

No, because the F-16 was designed as a multi-role fighter and it did extremely well. When it was announced that both the Air Force and Navy would use it, there was concern because of memories of the F-4 (a good plane for its time, but certainly not without its problems) and the compromises it had. When it was announced that it would also replace the Harrier and was planned to become the most common plane in the military, that's when people started fearing the worst.

Comment: Re:Drone It (Score 4, Interesting) 701 701

The main problem is the Marines wanting a replacement for the Harrier, something that can do STOL/STOVL operations, and that is completely under their control. The JSF was already under development, and the contractors said they could figure out how to make it fit the Marine requirements. What we got was a fighter that can't dogfight, a strike aircraft with a pitifully small payload, and the political impossibility of starting over from scratch.

One of the lessons that came out of this and the Zumwalt-class destroyer programs is that the military should stop trying to cram every feature into a program. While the proliferation of designs led to unwieldy logistics in the 60s, 70s, and 80s, the attempts to simplify everything have resulted in a reduced overall capability and the need to extend the lifetimes of planes the new projects were meant to replace. The F-15 and F-16 will still be around for decades, and may form a larger part of the tactical strike platforms than the USAF would like to admit. The same will probably be the case with the F/A-18E against the Navy's F-35C.

Dedicated designs are the most efficient. Some of them turn out to be spectacular at other jobs. The F-15 was designed with the adage "not a pound for air-to-ground" and yet from it was developed the F-15E Strike Eagle, an extremely effective air-to-ground platform. Hopefully the military is listening when it goes trying to build its next platform, a replacement for the B-1, B-2, and B-52 expected to come online between 2035 and 2045.

Comment: Re:It's called Rocket Science for a reason ... (Score 1) 307 307

I'm neither a kid nor have I forgotten the space race and the political squabbling that accompanied it. I want SpaceX to succeed, but I also want Orbital Sciences and Blue Origin to succeed, and anyone else that can reshape the space launch industry.

But there are people who desperately want to see Elon Musk fail. For that to happen, Tesla and/or SpaceX must fail. These people will hunt for any little indicator that Musk has bitten off more than he could chew and gleefully let everyone know about it.

I'm well aware that there are those who wanted (and still want) NASA to fail. They see NASA as the embodiment of government bureaucracy, slow and inefficient especially when compared to companies like SpaceX, and so they want to get rid of it. NASA is that, but mostly because the missions that they work on tend to be those difficult to replace: some extremely expensive satellites, interplanetary probes, and manned missions. A telecomm satellite lost on launch will be replaced by insurance and the contracted company will build another one. A failed satellite or probe may never be rebuilt (had New Horizons been lost, the atmosphere would have frozen and precipitated out before another probe could reach it). A failed manned mission may result in loss of life. Mission success therefore has higher priority than are the case with most commercial missions.

Comment: Re:no we can't (Score 2) 75 75

I find this an interesting statement. Running the numbers, I find that you'd have to be using a rocket burning something rather better than H2/O2 (we're talking Isp >500 just to reach escape speed, much less to reach the target rock) to allow two launches of a delta-IV heavy.


The fact that a Delta-IV Heavy has a LEO payload of over 27 tonnes is a fact. You don't need to "run the numbers". As for the kick stage, I didn't specify a propulsion system - for all we care (since we haven't established a timeframe), it could be an ion drive and not even take a rocket so large as a Delta IV-Heavy.

Meanwhile, the Falcon Heavy is to make its first launch this year, with double the payload of a Delta IV-Heavy. And as was mentioned, the Tsar Bomba was not optimized to be as lightweight as possible.

And this entirely ignores that noone actually has a Tsar Bomba sized nuke available to be detonated.

Oh, and you didn't allow for a backup

It's almost as if I didn't add "with enough advance warning" for that scenario and leave what "enough advance warning" is unspecified. But if there's another rock the size of the Chicxulub impactor out there and we don't see it until the last second, we deserve to get hit - we're no longer talking about a 50 meter spec (Tunguska-sized), rather a rock with a cross section 30% bigger than the island of Manhattan. We're talking about an impact of a scale that happens once every hundred million years or so.

Comment: OMG - matti makkonen .fi sms pioneer dead (Score 0) 31 31

A more appopriate version of the BBC's article:

OMG - matti makkonen .fi sms pioneer dead!!!
WTF - mm just died @63! #txtpioneerdeath was father of sms & dvlped idea of txt msg with phones. @2012 msged BBC that txt would be here "4EVR".
shoutout 2 Nokia for spreading sms w/Nokia 2010. thought txt good 4 language. was btw mng. director of Finnet ltd and "grand old man" & rly obsessed with tech.
OMFG people!

Comment: Re:no we can't (Score 2) 75 75

It is not only possible, but the easiest option, to "blow them up Armageddon style" (minus the drilling and the like). There's a lot of simulation work going on right now and the results have been consistently encouraging that even a small nuclear weapon could obliterate quite a large asteroid into little fragments that won't re-coalesce, while simultaneously kicking them out of their current orbit. A few years ago they were just doing 2d calcs, now they've gotten full 3d runs.

Think for a second about what nuclear weapons can do on Earth. Here's the crater of a 100kt nuclear weapon test. It's 100 meters deep and 320 meters wide. You could nearly fit a sizeable asteroid like Itokawa inside the hole. And that thing had Earth's intense gravity field working against it and was only 1/10th the size of weapons being considered here. In space you don't need to "blast out" debris with great force like on Earth, you merely need to give it a fractional meter-per-second kick and it's no longer gravitationally bound. And the ability of a nuclear shockwave to shatter rock is almost unthinkably powerful - just ignoring that many if not most asteroids are rubble piles and thus come already pre-shattered. Look at the "rubble chimneys" kicked up by even small nuclear blasts several kilometers underground (in rock compressed by Earth's gravity). Or the size of the underground cavity created by the wimpy 3kT Gnome blast - 28000 cubic meters. Just ignoring that it had to do that, again, working against Earth's compression deep underground, if you scale that up to a 1MT warhead the cavity would be the size of Itokawa itself.

You of course don't have to destroy an asteroid if you don't want to - nuclear weapons can also gently kick them off their path. Again, you're depositing energy in the form of X-rays into the surface of the asteroid on one side. If it's a tremendous amount of energy, you create a powerful shattering shockwave moving throughout the body of the asteroid. If it's lesser, however, you're simply creating a broad planar gas/plasma/dust jet across the asteroid, turning that whole side into one gigantic thruster that will keep pushing and kicking off matter until it cools down.

The last detail is that nuclear weapons are just so simple of a solution. There's no elaborate spacecraft design and testing program needed - you have an already extant, already-built device which is designed to endure launch G-forces / vibrations and tolerate the vacuum of space, and you simply need to get it "near" your target - the sort of navigation that pretty much every space mission we've launched in the past several decades has managed. In terms of mission design simplicity, pretty much nothing except kinetic impactors (which are far less powerful) comes close, and even then it's a tossup. Assuming roughly linear scaling with the simulations done thusfar, with enough advance warning, even a Chicxulub-scale impactor could be deflected / destroyed with a Tsar Bomba-sized device with a uranium tamper. Even though it was not designed to be light for space operations, its 27-tonne weight could be launched to LEO by a single Delta-IV Heavy and hauled off to intercept by a second launch vehicle.

Comment: Re:Not surprised (Score 5, Insightful) 312 312

Uber drivers are subsidized by everybody else. Taxi drivers have to pay high insurance rates because the act of driving a long distance every day for a ton of strangers is a job that inherently leads to a much higher statistical rate of payouts. If they're driving as a taxi on regular car insurance, it's you that's paying the bill for their swindle of the insurance system.

Comment: External influences (Score 4, Interesting) 111 111

When I was young, I played games from SJG, TSR, Palladium, R. Talsorian, ICE, FASA, and a bunch of one-off studios I can't remember now. Some of the systems worked really well, some required some tweaking, and others were essentially unplayable. But it was easy to see links between systems. Despite the occasional legal threats, there seemed to be a lot of borrowing each other's ideas. Palladium clearly was influenced by TSR (and I think they've admitted that the first version of their rules was essentially heavily modified D&D rules), and R. Talsorian's old D10/D6-based system seemed to have some influences from FASA.

When you're designing a game, what external influences help shape the game? How far can you adopt someone else's ideas before you have to start worrying about lawyers getting involved, and has that changed as the pen & paper RPG has waned in popularity?

Comment: Re:Because job outfit only look for links in googl (Score 1) 141 141

It wasn't that long ago that celebrities were blamed for making the sex tapes in the first place. That seems to be changing now, and for the better.

This will expand as people look around and see that we have foibles. Some people are still going to be jerks about it by not hiring someone because there's a picture of them from 20 years ago holding a joint or by hiring someone because they found the nudies posted a couple of years back and want the chance at seeing it for themselves. But past drug use isn't going to be nearly as much of a deal-killer as it is now, and even current drug use (at least for marijuana) is probably going to subside as a major concern as long as someone isn't high while on the job.

There will still be reasons people don't get hired for things that end up online. Posing while hanging out with the local Klansmen, for example, is going to make someone wary about hiring them for fear of having to deal with racism in the workplace. But being caught toking, flashing a nipple, or even engaging in sexual activities isn't going to be as important.

A commune is where people join together to share their lack of wealth. -- R. Stallman