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Comment Re:Just delete it (Score 2, Insightful) 192 192

This. Links in email are dead to me. I don't follow them, my mail client doesn't follow them, it's just so many wasted bytes. And that includes e-cards from friends/relatives. You want to send me something, send it to me, don't ask a third-party to.

(Sure, I make an exception for links I'm expecting (have asked for) but even then I'll copy them to my browser. HTML in my email is turned off.)

Comment Re:Would have saved itself (Score 2) 220 220

Actually, it would have been super cool if the first successful recovery of the first stage had been an emergency abort!

Something like this actually happened on the fourth or fifth flight of the DC-X test vehicle. It had made several successful launches, hovers, and vertical landings and the test profile had it going to higher and higher altitudes and doing some interesting maneuvers. Anyway, on the nearly fatal flight, due to wind conditions in the launch area, hydrogen gas (it was LH2/LO2 fueled) collected near the base of the rocket and ignited in a mild explosion at launch, with the shockwave blowing off some of the DC-X's airshell. The rocket continued climb-out, shedding more pieces as it went, as the observers watched. Pete Conrad (the astronaut, who as part of the DC-X team was controlling the flight from the ground) calmly clicked the "abort" sequence on the control computer. The DC-X stopped its ascent, hovered to burn off fuel (to lighten the load on the landing gear) and then landed safely.

Try that with any other rocket. (The DC-X's engines were modified RL-10s, much more deeply throttleable than Falcon's Merlin engines.)

Comment Re:Holy Jebus (Score 4, Informative) 220 220

And the depressing thing is that every one of them is there to prevent recurrence of a dishonesty that actually took place in the past.

And sometimes it's not even dishonesty, just stupidity. This was probably more true in the earlier days of aerospace. In a book about the design and construction of the Lunar Module (I think it's Chariots for Apollo, but could be wrong) there's a section on how many of the subcontractors had to be taught clean-room and quality techniques. There's one episode where one of the Grumman managers goes out to some paint pigment company who happened to get the contract for the silver-zinc LM batteries (because they had supplies of the right materials) and sees the batteries being assembled -- in a dirty shed by people who are smoking cigarettes while doing the assembly. (They threw out the entire batch, trained everyone how to do things the aerospace way, and set up a clean room, and AFAIK there was never a problem with the LM batteries.)

On the other hand the ladies sewing space suit pressure garments at the Playtex Girdle factory knew the astronauts' lives depended on what they were doing, and did it right the first time.

Comment Re:Potholes? (Score 1) 183 183

Having to heat the road itself completely negates that, as there's a LOT of road out there.

Actually heating the road is easy, with a little creativity. I was going to suggest adding plutonium to the road mix, but the same end could likely be achieved more cheaply by just using nuclear waste. Solves the waste problem at the same time.

Of course, there may be some undesirable side effects....

Comment Re:MUMPS criticism (Score 1) 166 166

but it was invented in the 1970s, before the concept of OOP had even been invented.

If it really was the 1970s, then it came some years after SIMULA-67, aka "ALGOL with objects". (I.e., SIMULA-67 was to ALGOL more or less as early C++ was to C.)

Everything in CS is (probably) older than you think. Including many of its practitioners ;-)

Comment Re:Probably an overreaction, but... (Score 2) 431 431

In Canada, a teen couldn't just go into a store and buy it, and even getting hold of large quantities of potassium nitrate was challenging.

Don't know how old you are, but when I was a kid in Toronto in the mid-1960s we could (and did) go down to the local drug store and buy potassium nitrate in 1-pound containers. Ditto sulphur, so long as you weren't stupid enough to try to buy both at the same time. (At least we never tried that, we just assumed that the cashier would be at least as knowledgeable as us and figure it out. Maybe not.)

Our sixth grade teacher did admonish us (not directly, but the class as a whole) about the dangers of such homebrew, with a few anecdotes of kids who had lost various body parts through doing stupid things like using metal implements to mix the stuff (sparks!), or treating it a bit too cavalierly.

Comment Re:Paranoia (Score 3, Informative) 431 431

Don't you know that most explosives work via a reaction with oxygen in the air?

Actually no, most don't, unless you're talking about fuel-air explosions (which can be bloody huge!). Most solid or liquid explosives use an oxidizer that's part of the mix -- or don't use an oxidizer as such at all, but rather their rather unstable molecular configuration degenerates to a lower energy state with much release of energy and component parts (most high explosives).

Comment Re:Microsoft loves Unix (Score 1) 265 265

"They ported the Unix for a Radio Shack system"

FTFY

Xenix was based on a source license from AT&T (the original, not the renamed Southern Bell) of Bell Labs' Version 7 Unix. Microsoft also made Xenix ports available for a number of other systems.

Plenty of other companies also made licensed ports of V7, which they couldn't call Unix (or UNIX) because AT&T wouldn't license the trademark. For example, Amdahl made UTS which ran on their IBM 370 clones (as well as on IBM hardware).

Comment Re:Why do I get the funny feeling that (Score 2) 265 265

It probably comes from reading the licenses, which you should try sometime. Note also the word forked.

You take some BSD-licensed code, make changes to it (creating a derivative version), then GPL-license the derivative. Anyone is still free to find the original BSD sources and make their own derivative, but they can't do anything with the GPL-licensed fork without following the GPL -- which includes GPL'ing any work derived from that.

Of course unless the changes introduced by the fork are particularly compelling, nobody is going to care. But it's still a possibility. The BSD licence allows it, just as it allows someone to make totally proprietary derivatives.

Comment Re:take from the aircraft/drone world (Score 1) 195 195

Even if you're just changing focus rather than the direction your eyes are pointing, you're looking away. There's very little information while driving which is so essential you can't flick your gaze away for a fraction of a second (you'd better be doing that anyway to check your mirrors). If traffic is that tight, you don't need to be looking at your speed, just stay with the flow. Your fuel gauge isn't going to suddenly leap from half-full to empty (if it does, you have other problems).

That said, a blinky light on the side mirror as a blind spot warning can't hurt, and maybe an unobtrusive but visible "master caution and warning" light could light up at the bottom of the windshield if some other instrument needs attention.

That said, for a fighter (or other high-performance aircraft) pilot who has to track multiple things simultaneously (where's the enemy? which weapons are armed, do they have a lock? what's my attitude after all this dogfighting?), a HUD is invaluable -- and said pilots are carefully selected and undergo a hell of lot of flight training and then a hell of a lot of training in using the HUD (and there's also an auditory component to that).

Comment Re:Reminds me of hands-free cell phones (Score 1) 195 195

I used to think that a hands-free phone should be fine when driving, since I was used to a fair bit of radio chatter while flying a plane.

But there are significant differences: radio chatter while flying is about the flying -- you're giving or getting info about your flight from ATC, if you're in formation you're discussing with the other aircraft where everyone is relative to each other and what your about to do, etc. You're not having a discussion about Junior's day in school or what John and Mary are up to or the latest server crash at work. One keeps your attention focussed on flying, the other distracts you from proper driving: where's your head at?

The other thing is that driving in typical traffic you should be paying as close attention to what the other vehicles are doing as if you're flying in close formation with a bunch of other planes. The latter is unlikely except for a very few pilots under special circumstances, most of the time in a plane you're at least many seconds (or minutes) away from other aircraft or obstacles (except landing or takeoff -- and you're generally not talking to anyone outside the cockpit at that point unless they're feeding you info about it.)

The latter is why we've had autopilots on aircraft for decades but nothing much better than cruise control (about equivalent to a wing leveller in terms of percentage control) on cars -- most of the time planes are in a much simpler environment.

Comment Re:Look outside, not inside (Score 1) 195 195

If you're driving a car under IFR rules there's something seriously wrong with you.

Sure, every pilot with some instrument training knows to trust the instruments when he can't see anything out the windows -- he also knows he's got ATC tracking him, helping him navigate and warning of other traffic or potential trouble (like t-storms).

If you're driving a car when you can't see out the windows you're a fucking loony, and a danger to everyone else out there. If you're relying on looking at the instruments (and hey, a GPS will work just fine in thick fog) instead of out the window, well, I just hope you run off the road quickly (oops, map was out of date) before you hit somebody else.

Comment Re:Look outside, not inside (Score 1) 195 195

Original poster wasn't talking about IFR -- obviously there's no point looking out the window in that case (if you're in cloud, you couldn't even see the wingtip).

But you're not going to get a new pilot flying IFR, because it takes a while to get the training and experience needed for that rating. Thing is, because a new pilot doesn't have the experience to know what attitudes look like (where's the horizon on the window? which way is it tilted? what sound is the engine making? etc), he's tempted to keep checking the instruments ... except that he hasn't figured out (at an intuitive level) all the interrelationships yet. He's looking at the attitude indicator to figure out if he's going up or down -- when he should be paying attention to the airspeed. He's focusing on "stepping on the ball" to coordinate his turns instead of looking out the window for that traffic he might be turning into and what the horizon is doing relative to the bug smear on the windshield.

Sure, you should be checking the panel periodically -- just like you should be checking the instrument panel periodically while driving -- but if you're VFR (and all driving is VFR, although with different minimums) you should be focussed on what the vehicle (and the others around it) is doing now (and about to do), not what the instruments are telling you it did a little while ago.

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