Re:Challenger cause NOT unknown, and admin's fault
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Latest Columbia News
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· Score: 1
While I am not discounting political influence, another (admitted) factor was costs and publicity. The Challenger launch had been postponed several times already and it was costing huge amounts of money everyday it was delayed. Add to that the fact that there was a lot of publicity on that mission (First teacher in space) and it only ups the pressure to get it off the ground.
Also, speaking of the engineers involved, there were (as I recall) at least two engineers who resigned because they wouldn't endorse the safety of the O-rings for the launch. But, I believe they worked for Norton Thiokol the (then) subcontractor for the solid-fuel rocket boosters (SRB's), not NASA. As we now know, the problem of "SRB O-ring erosion" was known and burn-through of the primary seal had occurred on earlier flights. There was also evidence to support that the erosion was inversely proportional to temperature. However, in those cases, the secondary seal held. So, in the case of the Challenger, the management essentially forced the engineers to say that the secondary would hold and therefore it was safe to launch.
(FYI: The Challenger "mishap" resulted in the addition of a tertiary seal a new "tongue in groove" design of the joints (between segments of the SRB's) that provided longer, less direct path between the burning propellant and the outside.)
Actually, the shuttle has parachutes. (Watch a landing sometime and you'll see 'em. And a little public interest would probably loosen the Congressional purse strings...) In fact, it uses parachutes for the exact same purpose that all earlier systems (Mercury, Gemini, Apollo and Soyuz) used: to assist in slowing the vehicle to a gentle stop at the very end.
I'm sure both Linux and Unix are used (and rightly so) for development, planning, ground computers, and maybe even experiments. But it is not running the flight systems. Even if you could find a compelling reason to do so, would have to do some serious shoehorning to get a Linux kernel to fit, much less have enough room left to do anything. Not to mention, Linux and Unix (in their native forms) are NOT real-time systems.
And since when does old = broken? Unix is "old" but it gets the job done and it has changed a lot over the years. Windows on the other hand, is pressing 20 years old itself and it still is only questionably reliable. (Someone can argue that if they like, but ask yourself if you would want to travel Mach 20+ at more than 40 miles up in something run by ANY version of Windows.)
In short, "if it ain't broke, don't fix it."
(Note: Don't interpret this to mean I am anti-Windows. I feel that it absolutely has its place. I just don't think that place is in anything super critical.)
At the risk of echoing most everyone else, NASA isn't Triple-A. A crew in orbit can't pull over to the curb, whip out the cell phone and expect Mission Control to answer and say, "Sure, no sweat. We'll have a tow truck out to you in half an hour."
While I do agree that the amount of funding allocated to NASA needs to be seriously reconsidered, I have to fault you on the military takeover suggestion.
I work for the military, the Air Force in fact, and I have news for you. Just because it is under military jurisdiction doesn't mean the purse strings break and money pours out. In fact, it is quite the opposite. Given the "who needs the military" attitude of recent years, funding is tighter than ever, especially for established, proven (a.k.a. "old") systems.
As for all the comments about those pesky "old" computers, I work on the avionics for one of the current front-line weapon systems and the computers are at least as old as those of the shuttle (maybe older in some cases). Are the designs old chronologically? Absolutely. Are they antiquated and out of date for what they do. Absolutely NOT.
Let's face it, aircrews aren't up there to play UT2K3 or type letters to Mom in Word. These computers do what they were designed to do and they do it well. (And are practically flawless compared to the F-22, at this point.) They were designed to be bullet proof (in some ways, literally as well as figuratively...). They do it with one less level of redundancy than the shuttle AND we are only a CMM level 3 organization. (Though we will soon be going for level 4.)
So, can you imagine just how freaking reliable and effective the "old" flight systems of the shuttle are? I think it is safe to say they likely never see a "Blue Screen of Death" during flight.
I also agree that today's Aviation Week article is probably the most reliable account of the FACTS so far. I believe that when it is all said and done and whether it was preventable or not, it will come down to a catastrophic structural failure. And even the newest, fastest computer in the world can't compensate for a wing that isn't there.
It seems to me that, of the U.S. population as a whole, the subset that makes up the/. crowd is probably the one most easily convinced to convert. (We are the ones most likely to at least be somewhat accustomed to using SI units.)As for the general population, most people would probably fall in the sheep category. They may gripe, but if you don't really give them a choice, they will eventually just adjust.
If you want to lobby to someone, start with the moron politicians. They're the ones that keep fouling up our attempts to convert. Of course, we've tried twice so far, so good luck doing any better. Hell, we can't even pick a freaking national language for fear of offending one group or another.
Just for fun, let's ignore the fact that this type of activity is completely illegal. Now, let's assume that this all singing, all dancing, cross-platform bit of coding genius actually exists and works. (Which is a stretch to say the least...) And, let's assume that the little Wonder Worm really has managed to infect 95% of the hosts connected to P2P networks.
So, assuming all of that (which is a lot to assume), this would leave the RIAA with a Library of Congress-caliber database of computers and the media files they contain. Great, good for them. Now what do they do with it?
Well, first they need to sort all of out according to which lists contain pirated material. Great, no problem. All, they have to do is search all the descriptions and filenames for stuff that "belongs" to them. That should be no problem for their in-house Super Code Monkeys; all they have to do is write intelligent sorting algorithms that can handle total lack of naming convention and total disregard for proper spelling or correct titles. Hmmmm...Maybe that isn't quite so easy.
But, difficult isn't impossible, so lets say they invested the time and effort to perfect their sorting algorithms and they have a nice list of the "bad" guys from the database. Now, all they have to do is tie the file list to actual people. No problem, just use their P2P usernames 'cause only one person on one computer uses a particular username, right? They can go after "kazaaliteuser" first; that guy has terabytes of stuff...
Ok, wait that won't work.... Ah, they can use IP addresses because everyone always has the same IP address and no one is behind a firewall and no one ever spoofs an IP address. Hmmm...ok, that won't work either...
Ahh, wait, they can use MAC addresses because everyone knows that is impossible to spoof and out of all the thousands of computers worldwide, there has never been a duplicate MAC address....
Oh, wait, that's not true either....
Ah, I have the solution! Patch for the Wonder Worm! Now, it has the ability to activate your webcam (regardless of type or even if you actually have one), snap your picture (I don't even want to think about what they will get that way....) and bind it to your file list. Then, they can wander around the world asking people if they recognize any of the people this little moving van full of photos.
Then, all they have to do is prove that: 1.) you don't own any of the CD's that contain music on your list, and 2.)Prove that you intentionally shared it on the P2P network (And that the installation program didn't automatically share your media folders for you.)
Wow, I'm scared now. I think I had better go delete all the illegal MP3's (all 10 or so of them) off of my hard drives so the all-seeing Evil Eye of the RIAA doesn't get me. Then I can go hide in a closet so they sky doesn't fall on me.
This is so terrible. What could possibly happen next? Wait, what if the porn industry cracks down on pirated porn? What if the form the PIAA? What will I do then??? Oh, the humanity!!!!!!!
I would say reliability is a huge issue and while American cars may sometimes suffer in some areas, there are a whole lot American V8's that have taken millions of miles of abuse and are still ticking. (Trust me, I've seen them.)
I really have to wonder what kind of shape your heavily modified WRX would be in after 250,000 miles. And here again, how driveable would it be in day to day, stop and go traffic? Sounds like it would probably be very peaky. (Considering you have spent $22K to turn it into a race car.) Not to mention, what would the value of the car be...
But, I do agree on the Hayabusa. They pretty well kick ass....;-)
Smaller displacement engines were starting to make inroads into American open wheel racing (CART and Indy) before those rules were changed to reduce boost as well.
Exactly the point all along. A bigger engine at the same boost pressure will make more power than the smaller one. Period. In order to run with the larger N/A engines, the smaller ones had to run higher bost pressures and when that was limited, they got there legs cut out from under them.
Dragsters? We both know that when it's all about acceleration and nothing else, it has to be a supercharger.
Actually, if you will notice, fast dragsters run in excess of 300mph. I would say that speed might be a factor here.
Also, a turbocharger is technically a supercharger, it is just a special subset of devices (superchargers) used to artificially increase intake charge density that happens to use wasted exhaust heat to drive the compressor. The automotive world simply uses the generic term supercharger to refer to crank driver compressors due to popular recognition.
Oh and, turbochargers are allowed in some classes of NHRA drag racing.
More cylinders reduce torsional vibration, but fundamental internal harmonics of the typical eight cylinder engine aren't that great. The best engines, based on internal harmonic vibrations, are Inline (Straight) 6s and 90 degree V16s. That's why almost all large commercial duty diesels are I6 turbocharged, not V8s of any kind. (It's also why the latest GMC truck engine is an I6.)
You are absolutely correct here, as I admitted when someone else pointed it out earlier. I worded it poorly and omitted some important caveats. (Read the rest of the thread.)
This is also wrong. Any given displacement is Bore x Stroke, not just bore. Large bore, short stroke engines are responsible for most of the high revvers, NOT small bore, long stroke. Dragsters, for example, use large bore, short stroke engines to get their high revs and acceleration. That's also what is behind Ferrari and Lamborghini's performance engines.
Do the math on the European V10's and V12's. In terms of displacement/cylinder, they are generally about equivalent or smaller than the average V8.
30 lbs of boost in an Indy car, you say??? BULL! 30 INCHES, not pounds! 30 inches of boost is less than 5 psi! Dragsters, on the other hand, need nothing but acceleration, so tremendous boost and huge displacement are BOTH normal. However, keep in mind that clamping forces required for the winning BMW Formula 1 engines were easily met with 1980s technology.
Granted, I was making a bit of an assumption here as that I am not terribly familiar with the rules of the Indy series. However, I find it hard to believe that the Indy cars are only running 5lbs. of boost when the Buick Turbo 3.8L V6 ('86-'87 and '89) in production form ran 15lbs. of boost. Especially when you consider that this engine was originally developed for Indy....
Actually, there is. It's called forced induction, and where it hasn't been legislated out of racing, it frequently does quite well to substitute for a whole lot of additional displacement.
Ah, but here again that is the point. If you took the larger engine used forced induction, it will still make more power. What people often fail to realize is that forced induction is just a source of "virtual displacement". In other words, assuming perfect volumetric efficiency, a perfect intercooler, and discounting changes in fluid dynamics from increased charge air density, an 1.5L engine at 15lbs (or roughly 30lbs MAP, or 1.5 atmospheres) will behave like a 3.0L engine.
Finally, don't count me on the "smaller engine" side of this argument based on this one post. I've driven Ferrari, Porsche, BMW, Lotus, Corvette, Lamborghini, Acura, Nissan, and many others. Small displacement and large displacement engines both have their merits and tradeoffs. I just hate to see incorrect stereotypes and urban myths that are propagated by big block enthusiasts who don't have their facts straight.
I couldn't agree with you more. And just so you (and everyone) know, I am a huge fan of turbocharged engines and own a couple of cars that have them. Actually, I am just an all around gearhead with few if any brand biases. I like cars, just not ignorance.
You are correct that this geometry is important for determining the behavior of the motor (more torque on the low end versus more power on the high end) and it also effects durability issues. (Bad geometry can lead to premature, out-of-round wear in the cylinder.)
But, if you really want to be technical, then you must separate bore and stroke into separate issues completely. Given two otherwise identical engines with different strokes, the shorter stroke will rev higher (and quicker).
However, if you have two otherwise identical engines with different bores, the smaller bored engine will rev quicker (Smaller pistons = less mass to accelerate) and it will also rev higher because smaller pistons use smaller rings.
The ring mass becomes an issue as piston (and ring) velocities increase. These velocities are a function of stroke and engine speed and as either (or both) of these increases, the forces exerted by the rings on the upper ring lands of the piston increase due to increased acceleration. (Think about it: regardless of stroke, a piston has to travel up and in the cylinder once per engine revolution. So, for a longer stroke engine, the piston has a greater distance to cover in the same amount of time. Therefore, it must travel faster.) And since, Force = Mass * Acceleration, if you increase the stroke of the engine or the mass of the rings (or both), you increase the force exerted on the top lip of the piston proportionally. Like anything, this thin rim of metal can only stand so much before it fails.
(Note: Similar issues apply to the shearing strength of the wrist pins and the tensile strength of the rods.)
While variable valve timing can be used to compensate for poor volumetric efficiency (to an extent), that is not it's only benefit. It, in effect makes one camshaft behave like several different camshafts all at once. (In other words, you could get a low-midrange torque cam and a mid-top end horsepower cam all in one physical unit.) In theory, if you could make it the system infinitely adjustable (as some companies are doing by eliminating the cam entirely and using solenoid-actuated valves), you can have the perfect cam for any and all engine speeds. Very Cool.
:)
True, while it is hard to accelerate, high reciprocating mass does lend inertia and therefore torque.
It's always nice stumbling across a fellow F-Body person.:)
You are right in that the LT1 (and LT4) block shares most of the general characteristics of the earlier small block Chevys. There are a few subtle differences (it uses reversed coolant flow, for instance). But, the big differences lie in the heads, induction and fuel injection, exhaust, and ignition.
The LS1 (and LS6) are a similar story, but have even less in common with the previous generations and yes, they are all aluminum to my knowledge.
Basically, they kept all the stuff that worked and improved everything else, which just makes them cheaper (and easier/more fun) to build, buy, and work on.:)
After I posted that, I was wondering if anyone would catch that one, so I'm sincerely impressed.
You are absolutely correct and I concede the point. I also worded the statement poorly and would also have had to include the caveat without sacrificing structural strength by offseting the common crank throws. In other words, I didn't account for the difference between even and odd fire V6's, V10's, and V12's. An easy modern example of this would be to compare the crank from a Ford V10 (even fire) to that of a Chrysler V10 (odd fire).
Here again, it isn't fair to compare cars to motorcycles. The hot motorcycle engines will rev easily to 13 or 14 thousand rpm (because of the small bore/low reciprocating mass). However, your average car engine would have turned itself into a large handgrenade by 7 or 8 thousand at the most. If you could turn a big engine that fast, it would still make more horsepower.
I am still assuming that he was refering to variable valve timing and variable intake volumes. The Ford mod. motors (including the Cobra's 4.6 liter DOHC) don't have this and could benefit from it. (As could any and all engines.)
Horsepower versus displacement is linear if you can keep the volumetric efficiency, burn rate/efficiency and reciprocating mass the same. (Granted, not necessarily an easy task.)
You are correct that the Big Block Chevy (396,454,502) will not rev as high, as fast, or as long as the small block 350 (due to more reciprocating mass). However, if they are in equal states of tune (the production 454's of today are built for low-end torque in trucks, where all-out performance isn't an issue), the Big Block will make more horsepower per rpm (up to it's admittedly lower limit). A fairly mild 454 can make 500hp easily, but it would take a pretty radical 350 to make the same. And the torque that the 454 will produce and the rpm it produces it at will be brutal.
Ummmm.....maybe it is just me, but this is also from the very website you quoted:
Power: 302.0 kw / 405.0 bhp @ 6000 rpm
Torque: 542.33 nm / 400.0 ft lbs @ 4800 rpm
(And that's without a turbo and intercooler.)
And I am guessing that, if you compared power and torque curves, the torque and power start to build a lot earlier with the Z06, making it much easier to drive day to day and potentially faster off the line.
And assuming that your figure of 0 to 60 in 4.3 for the WRX is correct, then the Z06 bests it at 3.9 seconds. (in a heavier car, with only two wheels pulling, thereby negating some of the difference between gravel and pavement)
So, here again, assuming all else equal (including All-wheel drive), the bigger displacement car would embarrass it.
I completely ignored it (the WRX) because it was irrelevant to the point I was making. I didn't say there couldn't be a fast four cylinder. (I have personally seen a 1100hp, 7.0 sec. 4 cylinder Chevy Cavalier.) But I did say that in order to make it perform with larger displacement engine it has to be so heavily modified that expense, derivability, and reliability become huge issues.
Which brings me back to the Elise. As I said before, how much does it cost? And as far as handling goes, it is easy to make a car handle if its top speed is 132mph. (Hell, the Chevy Beretta I drove in high school and college would come pretty close to that...) However, if you (somehow, probably by stuffing a "bulky" V8 in it) made it as fast as a (I'm guessing cheaper) Corvette Z06, then it's handling probably wouldn't be on par with the Z06.
(Side note: A "bulky" V8 isn't any longer than a 4 cylinder, just a little wider. Think about it...)
You are correct that power-to-weight and handling (depending on the intended use of the car) are very important. However, you must also acknowledge the price/performance ratio (my original point). And, like it or not, displacement is often the cheapest, simplest, and most reliable way to make more power.
I assume you are referring to the various variable valve timing schemes, and engine management systems and I absolutely agree that these are some very slick systems and that Detroit could (and is in the process of) learning from them.
However, I think we should give credit where credit is due. Most of the technology that the Japanese engines are making use of actually developed elsewhere. (i.e. Europe) But, Japan did bring the technology to the mainstream.
And I beg to differ on the Flintstone issue. To use a specific example, the GM LS1 and LS6 V8's are designs that are only a few years old. In terms of issues such as volumetric efficiency and the like, they are really very impressive. And then you have to consider that they manage to get 25 to 30mpg and good emissions from a normally aspirated, push-rod V8 making over 300hp without the use of variable valve timing, exotic variable volume intakes and the like (making the engines cheaper and easier to develop and produce). So really, the engines are quite impressive in their own right.
You are correct, the WRX is a very impressive little car, thanks in no small part to its all-wheel drive and the fact that it really is a little (and very light) car. Not to mention, when was the last time you saw someone on the street driving a WRC (race) spec WRX? That's like me justifying my argument by comparing a stock Honda to a Porsche 911 GT3 RS prepped for 24 hours at Le Mans.
I also agree that Lotus does produce exotic (and pretty) cars. However, the Elise isn't exactly a rocket ship. Zero to 62 in 5.1 seconds, while good, isn't astonishing. And 156hp? Your point was what, exactly? Oh, and how much did it cost again? Personally, I am more impressed by the Esprit. But, it also happens to be powered by a twin turbo V8.....
And unless my memory fails me, isn't a Hayabusa a MOTORCYCLE?!?! Let's see it has, a 1300cc (1.3L) engine and it weighs what, 480lbs? In other words, it has nearly as big an engine as and weighs roughly 75% less than your previously mentioned Elise. Isn't bringing that into a discussion about cars kind of like me saying that, if I strap my ass to a artillery shell, I can do 0-60 in about 1ms and top out at over 3000mph?
Now, as far as the gas comment goes, I would rather buy a little more gasoline, spend less per horsepower on the car, and have a car that is fast and doesn't look (and sound) like I have seen The Fast and the Furious one too many times....
I mean, if all out performance isn't an issue (and I'm sure no one around here really cares about that....), I'm guessing it's hard to beat the old Cyrix processors (at least watts/clock speed)? I've seen space heaters that dissipated less heat. And you should be able to pick up several of them really cheap.;-)
Sure they can, once they have had at least the cost of the car spent on them again and once they have been rendered completely useless for day to day street use because they require at least racing fuel and can't make power below 5 or 6 thousand rpm.
But, spend the same amount of money on a "lump of iron" (which are mostly aluminum now, anyway) V8 and it will blow the doors off of the little 4 cylinder.
Case in point, if a 4 cylinder turbo is so much better than a V6, V8, V10, etc, then why don't you see Indy cars, Top Fuel dragsters, or exotic super cars running them?
Internal combustion engines are essentially glorified air pumps. The more air it can pump the more power it can make. So, it follows that the larger the displacement, or the higher the intake charge density, or the faster you spin it, the more powerful the engine has a potential to be.
Four cylinders, no matter how "advanced" are still limited by physics and metallurgy. You can only make the cylinders so big, or boost it so high, or rev it so far before it breaks. By adding more cylinders you gain several advantages:
More cylinders allow for smoother running by reducing the number of degrees of crankshaft rotation between ignition events. (With a little geometry it can easily be shown why it's hard to beat an eight cylinder in this regard.)
For much the same reason, you increase torque potential by reducing the amount of "dead time" between ignition events.
You reduce the necessary bore size for a given displacement, thereby reducing piston ring mass and allowing for higher piston velocities and accelerations (higher revving for a given stroke length). Hence the reason many of the exotic engines have high cylinder counts for relatively small displacement (think Ferrari); they are intended to rev like mad.
You also reduce the clamping force required per cylinder head bolt (because there are generally more bolts) for a given cylinder pressure (thereby increasing boost potential). (Think blown dragster or Indy car, where 30 lbs. of boost isn't that big a deal.)
So, basically, the turbo fours aren't really all that advanced from a basic design sense. They are simply using lots and lots of gadgets to overcome inherent limitations. There is no substitute for displacement.
Ah, but sarcasm and exaggeration are often the only way to emphasize the true absurdity of comments made by the truly ignorant.
Re:The teacher passes responsiblity to student
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Professors vs. WiFi
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· Score: 1
What is this guy doing on/.? He can't possibly belong here if there is actually a girl who is willing to spend the day with him. And don't get me started on the "in bed" part....
Seriously though, while I agree that learning is a two-way street, it is important to keep in mind that the instructor has a leadership responsibility as well. How can students learn to be good, attentive students if the professors view teaching as an annoying distraction from their "real job"? (i.e. research)
Most of the classes I missed (which couldn't have added up to more than a semester or three) were missed either because the professor was just regurgitating from the text, or putting me to sleep with PowerPoint slides (which were available on the web).
But, for the few professors that took a sincere interest in teaching and went to some trouble to present material in a way that made it easy to relate to real-world problems, I was there religiously. They helped me see how I might actually use what I was learning, and they didn't make me feel like an irritating interruption in their day.
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While I am not discounting political influence, another (admitted) factor was costs and publicity. The Challenger launch had been postponed several times already and it was costing huge amounts of money everyday it was delayed. Add to that the fact that there was a lot of publicity on that mission (First teacher in space) and it only ups the pressure to get it off the ground.
Also, speaking of the engineers involved, there were (as I recall) at least two engineers who resigned because they wouldn't endorse the safety of the O-rings for the launch. But, I believe they worked for Norton Thiokol the (then) subcontractor for the solid-fuel rocket boosters (SRB's), not NASA. As we now know, the problem of "SRB O-ring erosion" was known and burn-through of the primary seal had occurred on earlier flights. There was also evidence to support that the erosion was inversely proportional to temperature. However, in those cases, the secondary seal held. So, in the case of the Challenger, the management essentially forced the engineers to say that the secondary would hold and therefore it was safe to launch. (FYI: The Challenger "mishap" resulted in the addition of a tertiary seal a new "tongue in groove" design of the joints (between segments of the SRB's) that provided longer, less direct path between the burning propellant and the outside.)
Actually, the shuttle has parachutes. (Watch a landing sometime and you'll see 'em. And a little public interest would probably loosen the Congressional purse strings...) In fact, it uses parachutes for the exact same purpose that all earlier systems (Mercury, Gemini, Apollo and Soyuz) used: to assist in slowing the vehicle to a gentle stop at the very end.
I'm sure both Linux and Unix are used (and rightly so) for development, planning, ground computers, and maybe even experiments. But it is not running the flight systems. Even if you could find a compelling reason to do so, would have to do some serious shoehorning to get a Linux kernel to fit, much less have enough room left to do anything. Not to mention, Linux and Unix (in their native forms) are NOT real-time systems.
And since when does old = broken? Unix is "old" but it gets the job done and it has changed a lot over the years. Windows on the other hand, is pressing 20 years old itself and it still is only questionably reliable. (Someone can argue that if they like, but ask yourself if you would want to travel Mach 20+ at more than 40 miles up in something run by ANY version of Windows.)
In short, "if it ain't broke, don't fix it."
(Note: Don't interpret this to mean I am anti-Windows. I feel that it absolutely has its place. I just don't think that place is in anything super critical.)
At the risk of echoing most everyone else, NASA isn't Triple-A. A crew in orbit can't pull over to the curb, whip out the cell phone and expect Mission Control to answer and say, "Sure, no sweat. We'll have a tow truck out to you in half an hour."
While I do agree that the amount of funding allocated to NASA needs to be seriously reconsidered, I have to fault you on the military takeover suggestion.
I work for the military, the Air Force in fact, and I have news for you. Just because it is under military jurisdiction doesn't mean the purse strings break and money pours out. In fact, it is quite the opposite. Given the "who needs the military" attitude of recent years, funding is tighter than ever, especially for established, proven (a.k.a. "old") systems.
As for all the comments about those pesky "old" computers, I work on the avionics for one of the current front-line weapon systems and the computers are at least as old as those of the shuttle (maybe older in some cases). Are the designs old chronologically? Absolutely. Are they antiquated and out of date for what they do. Absolutely NOT.
Let's face it, aircrews aren't up there to play UT2K3 or type letters to Mom in Word. These computers do what they were designed to do and they do it well. (And are practically flawless compared to the F-22, at this point.) They were designed to be bullet proof (in some ways, literally as well as figuratively...). They do it with one less level of redundancy than the shuttle AND we are only a CMM level 3 organization. (Though we will soon be going for level 4.)
So, can you imagine just how freaking reliable and effective the "old" flight systems of the shuttle are? I think it is safe to say they likely never see a "Blue Screen of Death" during flight.
I also agree that today's Aviation Week article is probably the most reliable account of the FACTS so far. I believe that when it is all said and done and whether it was preventable or not, it will come down to a catastrophic structural failure. And even the newest, fastest computer in the world can't compensate for a wing that isn't there.
Aren't you kind of preaching to the choir here?
/. crowd is probably the one most easily convinced to convert. (We are the ones most likely to at least be somewhat accustomed to using SI units.)As for the general population, most people would probably fall in the sheep category. They may gripe, but if you don't really give them a choice, they will eventually just adjust.
;-)
It seems to me that, of the U.S. population as a whole, the subset that makes up the
If you want to lobby to someone, start with the moron politicians. They're the ones that keep fouling up our attempts to convert. Of course, we've tried twice so far, so good luck doing any better. Hell, we can't even pick a freaking national language for fear of offending one group or another.
Oh, wait, Canada has that problem too....
Just for fun, let's ignore the fact that this type of activity is completely illegal. Now, let's assume that this all singing, all dancing, cross-platform bit of coding genius actually exists and works. (Which is a stretch to say the least...) And, let's assume that the little Wonder Worm really has managed to infect 95% of the hosts connected to P2P networks.
So, assuming all of that (which is a lot to assume), this would leave the RIAA with a Library of Congress-caliber database of computers and the media files they contain. Great, good for them. Now what do they do with it?
Well, first they need to sort all of out according to which lists contain pirated material. Great, no problem. All, they have to do is search all the descriptions and filenames for stuff that "belongs" to them. That should be no problem for their in-house Super Code Monkeys; all they have to do is write intelligent sorting algorithms that can handle total lack of naming convention and total disregard for proper spelling or correct titles. Hmmmm...Maybe that isn't quite so easy.
But, difficult isn't impossible, so lets say they invested the time and effort to perfect their sorting algorithms and they have a nice list of the "bad" guys from the database. Now, all they have to do is tie the file list to actual people. No problem, just use their P2P usernames 'cause only one person on one computer uses a particular username, right? They can go after "kazaaliteuser" first; that guy has terabytes of stuff...
Ok, wait that won't work.... Ah, they can use IP addresses because everyone always has the same IP address and no one is behind a firewall and no one ever spoofs an IP address. Hmmm...ok, that won't work either...
Ahh, wait, they can use MAC addresses because everyone knows that is impossible to spoof and out of all the thousands of computers worldwide, there has never been a duplicate MAC address....
Oh, wait, that's not true either....
Ah, I have the solution! Patch for the Wonder Worm! Now, it has the ability to activate your webcam (regardless of type or even if you actually have one), snap your picture (I don't even want to think about what they will get that way....) and bind it to your file list. Then, they can wander around the world asking people if they recognize any of the people this little moving van full of photos.
Then, all they have to do is prove that: 1.) you don't own any of the CD's that contain music on your list, and 2.)Prove that you intentionally shared it on the P2P network (And that the installation program didn't automatically share your media folders for you.)
Wow, I'm scared now. I think I had better go delete all the illegal MP3's (all 10 or so of them) off of my hard drives so the all-seeing Evil Eye of the RIAA doesn't get me. Then I can go hide in a closet so they sky doesn't fall on me.
This is so terrible. What could possibly happen next? Wait, what if the porn industry cracks down on pirated porn? What if the form the PIAA? What will I do then??? Oh, the humanity!!!!!!!
Note that he did specify sold in the U.S.
I would say reliability is a huge issue and while American cars may sometimes suffer in some areas, there are a whole lot American V8's that have taken millions of miles of abuse and are still ticking. (Trust me, I've seen them.)
;-)
I really have to wonder what kind of shape your heavily modified WRX would be in after 250,000 miles. And here again, how driveable would it be in day to day, stop and go traffic? Sounds like it would probably be very peaky. (Considering you have spent $22K to turn it into a race car.) Not to mention, what would the value of the car be...
But, I do agree on the Hayabusa. They pretty well kick ass....
Smaller displacement engines were starting to make inroads into American open wheel racing (CART and Indy) before those rules were changed to reduce boost as well.
Exactly the point all along. A bigger engine at the same boost pressure will make more power than the smaller one. Period. In order to run with the larger N/A engines, the smaller ones had to run higher bost pressures and when that was limited, they got there legs cut out from under them.
Dragsters? We both know that when it's all about acceleration and nothing else, it has to be a supercharger.
Actually, if you will notice, fast dragsters run in excess of 300mph. I would say that speed might be a factor here.
Also, a turbocharger is technically a supercharger, it is just a special subset of devices (superchargers) used to artificially increase intake charge density that happens to use wasted exhaust heat to drive the compressor. The automotive world simply uses the generic term supercharger to refer to crank driver compressors due to popular recognition.
Oh and, turbochargers are allowed in some classes of NHRA drag racing.
More cylinders reduce torsional vibration, but fundamental internal harmonics of the typical eight cylinder engine aren't that great. The best engines, based on internal harmonic vibrations, are Inline (Straight) 6s and 90 degree V16s. That's why almost all large commercial duty diesels are I6 turbocharged, not V8s of any kind. (It's also why the latest GMC truck engine is an I6.)
You are absolutely correct here, as I admitted when someone else pointed it out earlier. I worded it poorly and omitted some important caveats. (Read the rest of the thread.)
This is also wrong. Any given displacement is Bore x Stroke, not just bore. Large bore, short stroke engines are responsible for most of the high revvers, NOT small bore, long stroke. Dragsters, for example, use large bore, short stroke engines to get their high revs and acceleration. That's also what is behind Ferrari and Lamborghini's performance engines.
Do the math on the European V10's and V12's. In terms of displacement/cylinder, they are generally about equivalent or smaller than the average V8.
30 lbs of boost in an Indy car, you say??? BULL! 30 INCHES, not pounds! 30 inches of boost is less than 5 psi! Dragsters, on the other hand, need nothing but acceleration, so tremendous boost and huge displacement are BOTH normal. However, keep in mind that clamping forces required for the winning BMW Formula 1 engines were easily met with 1980s technology.
Granted, I was making a bit of an assumption here as that I am not terribly familiar with the rules of the Indy series. However, I find it hard to believe that the Indy cars are only running 5lbs. of boost when the Buick Turbo 3.8L V6 ('86-'87 and '89) in production form ran 15lbs. of boost. Especially when you consider that this engine was originally developed for Indy....
Actually, there is. It's called forced induction, and where it hasn't been legislated out of racing, it frequently does quite well to substitute for a whole lot of additional displacement.
Ah, but here again that is the point. If you took the larger engine used forced induction, it will still make more power. What people often fail to realize is that forced induction is just a source of "virtual displacement". In other words, assuming perfect volumetric efficiency, a perfect intercooler, and discounting changes in fluid dynamics from increased charge air density, an 1.5L engine at 15lbs (or roughly 30lbs MAP, or 1.5 atmospheres) will behave like a 3.0L engine.
Finally, don't count me on the "smaller engine" side of this argument based on this one post. I've driven Ferrari, Porsche, BMW, Lotus, Corvette, Lamborghini, Acura, Nissan, and many others. Small displacement and large displacement engines both have their merits and tradeoffs. I just hate to see incorrect stereotypes and urban myths that are propagated by big block enthusiasts who don't have their facts straight.
I couldn't agree with you more. And just so you (and everyone) know, I am a huge fan of turbocharged engines and own a couple of cars that have them. Actually, I am just an all around gearhead with few if any brand biases. I like cars, just not ignorance.
But, if you really want to be technical, then you must separate bore and stroke into separate issues completely. Given two otherwise identical engines with different strokes, the shorter stroke will rev higher (and quicker).
However, if you have two otherwise identical engines with different bores, the smaller bored engine will rev quicker (Smaller pistons = less mass to accelerate) and it will also rev higher because smaller pistons use smaller rings.
The ring mass becomes an issue as piston (and ring) velocities increase. These velocities are a function of stroke and engine speed and as either (or both) of these increases, the forces exerted by the rings on the upper ring lands of the piston increase due to increased acceleration. (Think about it: regardless of stroke, a piston has to travel up and in the cylinder once per engine revolution. So, for a longer stroke engine, the piston has a greater distance to cover in the same amount of time. Therefore, it must travel faster.) And since, Force = Mass * Acceleration, if you increase the stroke of the engine or the mass of the rings (or both), you increase the force exerted on the top lip of the piston proportionally. Like anything, this thin rim of metal can only stand so much before it fails.
(Note: Similar issues apply to the shearing strength of the wrist pins and the tensile strength of the rods.)
It's always nice stumbling across a fellow F-Body person. :)
:)
You are right in that the LT1 (and LT4) block shares most of the general characteristics of the earlier small block Chevys. There are a few subtle differences (it uses reversed coolant flow, for instance). But, the big differences lie in the heads, induction and fuel injection, exhaust, and ignition.
The LS1 (and LS6) are a similar story, but have even less in common with the previous generations and yes, they are all aluminum to my knowledge.
Basically, they kept all the stuff that worked and improved everything else, which just makes them cheaper (and easier/more fun) to build, buy, and work on.
After I posted that, I was wondering if anyone would catch that one, so I'm sincerely impressed.
You are absolutely correct and I concede the point. I also worded the statement poorly and would also have had to include the caveat without sacrificing structural strength by offseting the common crank throws. In other words, I didn't account for the difference between even and odd fire V6's, V10's, and V12's. An easy modern example of this would be to compare the crank from a Ford V10 (even fire) to that of a Chrysler V10 (odd fire).
Ummmm.....maybe it is just me, but this is also from the very website you quoted:
Power: 302.0 kw / 405.0 bhp @ 6000 rpm Torque: 542.33 nm / 400.0 ft lbs @ 4800 rpm (And that's without a turbo and intercooler.)
And I am guessing that, if you compared power and torque curves, the torque and power start to build a lot earlier with the Z06, making it much easier to drive day to day and potentially faster off the line.
And assuming that your figure of 0 to 60 in 4.3 for the WRX is correct, then the Z06 bests it at 3.9 seconds. (in a heavier car, with only two wheels pulling, thereby negating some of the difference between gravel and pavement)
So, here again, assuming all else equal (including All-wheel drive), the bigger displacement car would embarrass it.
Still lot's of holes, but not a bad analogy overall.
Man, I finally find an ally and they don't even put their name on the post! :)
I completely ignored it (the WRX) because it was irrelevant to the point I was making. I didn't say there couldn't be a fast four cylinder. (I have personally seen a 1100hp, 7.0 sec. 4 cylinder Chevy Cavalier.) But I did say that in order to make it perform with larger displacement engine it has to be so heavily modified that expense, derivability, and reliability become huge issues.
Which brings me back to the Elise. As I said before, how much does it cost? And as far as handling goes, it is easy to make a car handle if its top speed is 132mph. (Hell, the Chevy Beretta I drove in high school and college would come pretty close to that...) However, if you (somehow, probably by stuffing a "bulky" V8 in it) made it as fast as a (I'm guessing cheaper) Corvette Z06, then it's handling probably wouldn't be on par with the Z06.
(Side note: A "bulky" V8 isn't any longer than a 4 cylinder, just a little wider. Think about it...)
You are correct that power-to-weight and handling (depending on the intended use of the car) are very important. However, you must also acknowledge the price/performance ratio (my original point). And, like it or not, displacement is often the cheapest, simplest, and most reliable way to make more power.
Ah, someone with a thoughtful rebuttal! :)
I assume you are referring to the various variable valve timing schemes, and engine management systems and I absolutely agree that these are some very slick systems and that Detroit could (and is in the process of) learning from them.
However, I think we should give credit where credit is due. Most of the technology that the Japanese engines are making use of actually developed elsewhere. (i.e. Europe) But, Japan did bring the technology to the mainstream.
And I beg to differ on the Flintstone issue. To use a specific example, the GM LS1 and LS6 V8's are designs that are only a few years old. In terms of issues such as volumetric efficiency and the like, they are really very impressive. And then you have to consider that they manage to get 25 to 30mpg and good emissions from a normally aspirated, push-rod V8 making over 300hp without the use of variable valve timing, exotic variable volume intakes and the like (making the engines cheaper and easier to develop and produce). So really, the engines are quite impressive in their own right.
You are correct, the WRX is a very impressive little car, thanks in no small part to its all-wheel drive and the fact that it really is a little (and very light) car. Not to mention, when was the last time you saw someone on the street driving a WRC (race) spec WRX? That's like me justifying my argument by comparing a stock Honda to a Porsche 911 GT3 RS prepped for 24 hours at Le Mans.
I also agree that Lotus does produce exotic (and pretty) cars. However, the Elise isn't exactly a rocket ship. Zero to 62 in 5.1 seconds, while good, isn't astonishing. And 156hp? Your point was what, exactly? Oh, and how much did it cost again? Personally, I am more impressed by the Esprit. But, it also happens to be powered by a twin turbo V8.....
And unless my memory fails me, isn't a Hayabusa a MOTORCYCLE?!?! Let's see it has, a 1300cc (1.3L) engine and it weighs what, 480lbs? In other words, it has nearly as big an engine as and weighs roughly 75% less than your previously mentioned Elise. Isn't bringing that into a discussion about cars kind of like me saying that, if I strap my ass to a artillery shell, I can do 0-60 in about 1ms and top out at over 3000mph?
Now, as far as the gas comment goes, I would rather buy a little more gasoline, spend less per horsepower on the car, and have a car that is fast and doesn't look (and sound) like I have seen The Fast and the Furious one too many times....
Actually, I think Yahoo should follow suit with Microsoft and sue Wahoo for trademark infringement. ;-)
I mean, if all out performance isn't an issue (and I'm sure no one around here really cares about that....), I'm guessing it's hard to beat the old Cyrix processors (at least watts/clock speed)? I've seen space heaters that dissipated less heat. And you should be able to pick up several of them really cheap. ;-)
But, spend the same amount of money on a "lump of iron" (which are mostly aluminum now, anyway) V8 and it will blow the doors off of the little 4 cylinder.
Case in point, if a 4 cylinder turbo is so much better than a V6, V8, V10, etc, then why don't you see Indy cars, Top Fuel dragsters, or exotic super cars running them?
Internal combustion engines are essentially glorified air pumps. The more air it can pump the more power it can make. So, it follows that the larger the displacement, or the higher the intake charge density, or the faster you spin it, the more powerful the engine has a potential to be.
Four cylinders, no matter how "advanced" are still limited by physics and metallurgy. You can only make the cylinders so big, or boost it so high, or rev it so far before it breaks. By adding more cylinders you gain several advantages:
So, basically, the turbo fours aren't really all that advanced from a basic design sense. They are simply using lots and lots of gadgets to overcome inherent limitations. There is no substitute for displacement.
Ah, but sarcasm and exaggeration are often the only way to emphasize the true absurdity of comments made by the truly ignorant.
What is this guy doing on /.? He can't possibly belong here if there is actually a girl who is willing to spend the day with him. And don't get me started on the "in bed" part....
Seriously though, while I agree that learning is a two-way street, it is important to keep in mind that the instructor has a leadership responsibility as well. How can students learn to be good, attentive students if the professors view teaching as an annoying distraction from their "real job"? (i.e. research)
Most of the classes I missed (which couldn't have added up to more than a semester or three) were missed either because the professor was just regurgitating from the text, or putting me to sleep with PowerPoint slides (which were available on the web). But, for the few professors that took a sincere interest in teaching and went to some trouble to present material in a way that made it easy to relate to real-world problems, I was there religiously. They helped me see how I might actually use what I was learning, and they didn't make me feel like an irritating interruption in their day.