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Comment: Re:And if I am ridding in the car? (Score 1) 364

by cmdahler (#47873163) Attached to: Text While Driving In Long Island and Have Your Phone Disabled

If my wife is driving and I am riding then what?

Who cares? You're missing the point of the whole punishment aspect of a law like this. If you're dumb enough to think you can safely text while driving, then I for one wouldn't have much sympathy for you bitching later on that you can't text while you're a passenger. You deserve what you got. This sort of law and punishment would be sort of like making it illegal to be stupid. I suppose the problem is that stupid people, by definition, are too stupid to understand that they're being punished for being stupid, but at least it would keep you from texting while you're driving and turning your stupidity into an active menace to society.

Comment: Re:Distance and Radiation make it a moot point.... (Score 1) 112

by cmdahler (#46869711) Attached to: Proposed Indicator of Life On Alien Worlds May Be Bogus
That reminds me of an old SF book called Dragon's Egg, about life that developed on the surface of a neutron star. The molecular structure of this life was based on particles interacting via the strong force rather than the electromagnetic force, and because of that their chemical processes ran about a million times faster than ours. The main bulk of the story took place over a couple of months of our time, in which a spacecraft of ours was orbiting this neutron star. In that two-month timeframe, the beings on the star evolved from primitive savages to a highly advanced civilization, far more technologically advanced than ours. We were able to communicate with them, but from their standpoint it would take nearly a whole lifetime for just a few messages to be exchanged back and forth. Interesting story.

Comment: You want you 15 minutes with that? (Score 3, Insightful) 176

by cmdahler (#41396135) Attached to: Man Pays For Cross-Country Trip Using Bacon As Currency
Of course, the fact that he's being followed around by a film crew has nothing to do with his success at bartering his bacon. That's a pretty ridiculous stunt. He might as well just go up to all these people and say, "Hey, if you'll give me decent seats to this game, I'll let my film crew here get a clip of you handing me the tickets and you might wind up on national TV!"

Comment: Re:Umm, no... (Score 1) 449

by cmdahler (#36273236) Attached to: Flight 447 'Black Box' Decoded

That's because Airbus actually trained pilots to react this way since, according to them, stalling an Airbus was impossible. To recover from an "almost stall" (which they thought was the worst that could happen), you just pull back on the stick and slam the throttles forward, and the plane would automatically maintain the maximum angle of attack without stalling. Oops, Airbus got it wrong again.

That's only in normal law - you need to research your details before you start bashing something you have no experience with. Stall protections are lost in alternate law, and recovering from a stall in alternate law is part of standard Airbus training.

Comment: Re:Actually, you're right. (Score 5, Informative) 449

by cmdahler (#36270148) Attached to: Flight 447 'Black Box' Decoded

What's most interesting in this case is that the systems warned the pilots of an impending stall, but then once they were in a stall, there was no warning at all, as if they had recovered from the stall. That's really unfortunate.

That's because once the airspeed drops below 60 knots, the input from the angle of attack vane is ignored by the flight computer. The computed angle of attack is how the flight computer determines the airplane is approaching a stall, so without a valid input from the AOA vane, the computer can't sound the stall warning. The AOA vane is just a triangle-shaped piece of metal sticking off the side of the airplane on a little lever, so the airflow naturally positions it, just like a weather vane. As the angle of attack changes, the vane moves, providing an input to the computer. Below about 60 knots, though, there isn't enough airflow to move the AOA vane to a reliable, steady position, so the information is discarded by the computer.

In this case, you're right, it was unfortunate because it provided a confusing result to the crew. They had pulled the airplane's nose up into a stall, and when the airspeed dropped below 60 knots, the stall warning stopped. At one point, the crew did lower the nose of the airplane, which caused an increase of airspeed, which is of course precisely what they needed, but as the airspeed increased beyond 60 knots, the stall warning suddenly started back up. That made them think that what they were doing was making the situation worse, not better, when in fact they were doing the right thing. They pulled the nose back up and then never got it back down until they hit the water. Even when valid, the AOA vane never indicated an angle of attack of less than 35 degrees - generally speaking, almost any general or commercial aviation wing will be well into a stall by about 15 or 16 degrees AOA.

Comment: Re:Umm, no... (Score 1) 449

by cmdahler (#36270046) Attached to: Flight 447 'Black Box' Decoded

Color me ignorant (I don't know much about 'planes... just enough to avoid them), but wouldn't an independently powered GPS tell which way is up? Like, uh, constantly?

No. A GPS does not provide attitude information. It merely gives you your three-dimensional position (lat/long/altitude). In any case, on a commercial airplane such as the A330, the GPS data is not generally presented directly to the crew - you can find it, but it's buried in some menus on the computer. In fact, unless you look through the menus on those computers, you have no direct indication that GPS is even installed on the airplane or not.

Comment: Re:Memory Part? (Score 4, Informative) 205

by cmdahler (#35980670) Attached to: Mystery Air Crash Black Box Found Sans Memory Part

From the article, it sounds like the flight data recorder has basically been smashed to pieces. This is usually what happens to them; they're really only useful in relatively low-speed accidents.

That's not the case at all. FDRs commonly survive catastrophic high speed accidents. For example, USAir 427 in 1994 crashed in a near vertical nose-down attitude, and pretty much all that was left of that accident was small bits and pieces. The FDR was recovered and was usable. They rolled and went nose down from 6,000 feet, and the last data on the recorder indicated an airspeed of 261 knots (300 mph, or about 135 meters per second), at a 80 nose-down attitude, virtually straight into the ground. If an FDR can survive that, it can survive damn near anything.

Comment: Re:I'm using the 105Mbit service. The datacap is r (Score 1) 372

by cmdahler (#35839482) Attached to: Comcast's 105MBit Service Comes With Data Cap
Whatever happened to sending the kids outside to play soccer or some make-believe game? No wonder this nation is so overweight and no one knows how to socialize when people whine about not having enough bandwidth to consume this level of TV watching. I let my kids watch about an hour of TV a day, tops. Then the damn thing gets turned off. If they complain about being bored I tell them I'll happily put a puzzle together with them or get the chess board out or put on the baseball glove. If anyone is consuming 250GB a month on a regular basis with gaming and media, you need to seriously take a hard look at your life and get out the door every now and then. The ISPs in this country would do the healthcare system a serious favor if they would all put a 10GB/month cap on everyone's internet usage. (This is hilarious: I'm turning into my dad!)

Comment: Re:No. (Score 1) 1486

by cmdahler (#35746734) Attached to: Is Science Just a Matter of Faith?

However, science encourages you to disagree, debate, and question things for yourself.

Well, that pretty much rules out anyone on Slashdot as being a true scientist, then. It also rules out the vast majority of scientists themselves. There are very few people, especially in science, who take well to disagreement and debate. In fact, the general public, being far removed from a deep, intricate understanding of science, is probably far more tolerant of scientific debate and disagreement than the scientists themselves. Science, in my experience, pays a lot of lip service to encouraging debate and disagreement; the reality is generally far removed from the theory. I see no practical difference between the modern scientist and the priest.

Comment: Re:...as opposed to what? (Score 1) 148

by cmdahler (#35711550) Attached to: Robots Find Wreckage of AF447
Painting results in a smooth surface, so long as it's kept clean. Thus, the fuel savings from the reduced drag offset the cost of hauling around that extra weight in paint. For airlines like American, which go with an unpainted fuselage, they have to polish that aluminum at frequent intervals to keep it smooth, which adds up to a lot of expense and wear on the skin. I've read studies in the past saying it's basically a toss-up as to which methodology costs/saves more.

What this country needs is a dime that will buy a good five-cent bagel.

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