> One of the most impressive things I've seen a > Raptor do so far (on Discovery Wings, of course, > heh) is fly backwards... jet is flying straight > and level, pilot pulls the throttle all the way up > and the jet actually goes into a "controlled > stall" and moves backwards (or so it appears > visually) for a short distance. Hell if I know if > it's useful in combat -- but nifty to the > layperson.
Perhaps. I've seen my flight instructor doing the same thing in a 1939 Piper Cub (SuperCub with a bigger engine) while towing banners. He'd fly into a strongish headwind down the beach, and ride the stall at somewhere around 32mph. Depending on the wind speed, he'd either be hovering or flying backward.
For the F-22 to perform the same stunt, the aircraft would have to be either flying against the jet stream at stall speed, or they'd have to go into a ballistic attitude, 'sitting on the jets', and use the vectored thrust to move backwards as well as staying aloft.
Of course, for the difference in price, I'll take the cub anyday.;>
> In what way is Ada better than Java in this > respect? I only know a little about Ada, so this > is a serious question. My understanding is that > Ada and Java have very similar safety goals > (especially with respect to exceptions) so I'm > curious about what you think Ada gets right and > Java gets wrong.
Let me be fair.. as a language, I'm not terribly familiar with java. I have spent a great amount of time supporting Java developers on the system level, however. I have seen developers write java code that crashes in very gnarly ways, and had to support them. I've seen java interpreters just spontaneously die. Now this could certainly be buggy implementations, and not a bad language specification. While that was not the impression I was given by the developers in question, I don't deny the possibility. I have, personally, never seen an Ada program 'crash'. I have never seen an Ada program exit in any way other than an unhandled exception or a normal exit. I've seen Java do a lot worse.
I will not say that java, as a specification, is less 'safety critical' than Ada, only that I am not aware that it is as much so. If the implementation is the problem, as I mentioned that it could be above, then pending better implementations, I'll check back in with this topic.:>
In closing, though, I have to say that, from the information I have, an Ada program is about a billion times more reliable than a Java program, when you're talking about large (Or huge) applications. Ada also has the benefit of a big experience base, mathematical analysis, review, etc.
I'm open to comments regarding Java implementations, stability, and the safety-critical methodologies present (Or lacking) in Java from those more familiar with the language.
> This means the developers were forced to use > Ada, but why ? To me, it seems some suits think > it's especially "safe" for some reason, does > anyone know more about that ?
Ada is especially safe. It is, in fact, one of the VERY few safety critical environments you will find. It's very simple- A safety critical program must never exit and give up control functionality entirely, no matter what happens. There are many things that you can do with C/C++/Java that will cause a crash unrecoverable by the system.
Ada is designed to inherantly prevent a programmer who follows the appropriate standards from writing a program that can just crash and exit. As long as every possible exception has a handler, an Ada program can be written that will not crash.
> But I think you can try to make a programming > language as "safe" as you want, it won't prevent > you from implementing bugs, it just causes a > false sense of safety instead which can be even > more dangerous, IMHO.
Bugs are universal. But bugs in a C program can cause the controlling system to shut it down with prejudice (Sig 11 and others), and it doesn't offer the automatic safety nets Ada does. Can you write safety critical software in C/C++/Java? Certainly. It's all a matter of methodology. Ada enforces the methodology, which is why people hate it. They can't do cute, horrible hacks like they can in C/C++, and Ada requires explicit specification.. Ada has specific standards of implementation for software, and a good inherant design. It is designed, from the ground up, as a 'safety critical' language, and for the most part succeeds on its own merit.
I do understand the widespread animosity towards Ada. People don't like the verbose, very specific code. Progammers often want to bend the langauge over their knees and perform horrid hacks that make reasonable people blanch in fear, but Ada doesn't really allow that. Programmers are often forced to learn Ada in structured learning courses, and forced to read the Ada RM. They end up hating it because of the language and terminology used, because of the verbosity of the language, because of some of the difficult concepts of Ada, etc..
But it really is a fine language. (I'm sure many people will disagree with me without really having an objective or informed viewpoint, but that's just how it goes)
> Sorry, but if you have to reboot the ENTIRE > avionics system of a F-22 you're fucked to say > mildly.
Avionics and flight control systems are separate and extremely disparate.
> This plane is always in a controlled stall,
That is extremely unlikely. A stall is defined as a condition when the wing exceeds the critical angle of attack (Which is in turn defined as the angle of attack where the airfoil is no longer producing lift, but is instead experiencing separated and turbulent airflow).
Is a typical graph depicting Cl (Coefficient of Lift) and its relation to Angle of Attack. Lift (And induced drag) increases with an increase of angle of attack or an increase in speed.
Angle of Attack, for your reference, is defined as the angle between the chord line and the relative wind. The chord line of an airfoil is an imaginary line connecting its leading edge with its trailing edge. The 'Relative wind' is defined as the flight path of the aircraft.
Therefore, for an airplane to be flown perpetually in a state of controlled stall, its airfoil would always be pitched up at approximately 17 degrees relative to the flight path of the airplane.
Would be quite funny to watch, actually.:>
There's a lot of misunderstanding about 'stalls' out there. What the F-22 may be able to do better than more 'conventional' airplanes, and perhaps that to which you refer, is ride the edge of an impending stall (In a high speed, hard banked, high-G turn, for example) without diverging from controlled flight.
I for one don't care for fly-by-wire. Perhaps I'm old fashioned.:>
I'd rather the airplane do what I told it to do than what it thinks I should have told it to do. Same reason I like Unix- I don't want my airplane, or my computer, doing what it thinks I meant rather than what I told it.:>
While I think your points aren't terribly coherent, and the structure and grammar of your post isn't great, the point you make is excellent, I think.
I do agree with your assesment overall.
The problem is, many of the people who disagree with you don't understand poor. They come from nice well-off parents in nice little neighborhoods in nice parts of town. They may even think of themselves as 'impovrished' since they never got that Atari 2600, Commodore PET, Amiga or Nintendo they wanted, when 'all their friends had one', or maybe their parents had to drive a *Gasp* used car.
They may have even not been fully funded for the college of their choice by their parents (What a horror!).
No, most of the dissenters probably think, "Look at me! I'm making all this money, and I had to go to college for eight long years to get where I am. I even had to take a minimum wage job when I was in college- I was a poor college student! I know poverty! And look what I made of myself."
I know this, because I've had this debate with many people, and they truly see it that way. They don't realize that poverty- The sort of poverty in which a MAJORITY of Americans live, is the sort of poverty where you work two jobs and your spouse works one, so you can make ends meet enough to hopefully own a house of your own before you die.
It is the sort of poverty where there is no Martha Stewart Osterizer Plus in the kitchen- Where you instead have to balance buying food with taking little Amy to the doctor to see about her constant, wracking cough (since neither of your jobs offers health insurance).
It's the kind of poverty where you don't cry because you can't get the Lexus and have to settle for the Honda, but instead feel lucky to have found the $200 Toyota that's got 260k miles and is rusted out with no heat, much less radio. Oh wait, I forget- The dissenter would say, "Driving is a privelege, not a right and if they can't afford to drive, they should walk!'
Walk, should they? Or maybe take the bus? When they have to get their kids to school, get to job one, get home in time for a quick dinner before heading to job two, and get back home for a few hours' sleep, walking or bussing might easily take another three hours.
And what happens when they find out that Amy has been living with an upper respiratory infection, and has heavy scarring in 35% of her lungs which has led to a serious case of bacterial pneumonia taking hold. Amy needs to stay overnight at the hospital, a fluid IV ($90 per litre of glucose cocktail with antibiotic, changed bi-hourly, $50 disposable IV needle, $45 solution container, $20 tubing, $5 tape), blood tests ($15 syringe/needle, $600 haemogram), etc etc, and the final bill comes to well over $1,500.
Stuff happens. And when stuff happens, and money is short, things can get really bad.
Poverty is a pit with slippery-sloped sides that is very difficult to pull yourself out of. It is not a lack of intellect (Some of the sharpest people I know were poor), nor a lack of work ethic- Do those who dissent really think that they, with their 8-5 manager job are working harder than Joe down the street at the tire place?
Ah well, this has turned out much longer than I intended initially, but I hate seeing people with no real concept of what 'poverty' is talking amongst themselves about how superior they are to the lazy, shiftless, stupid poor 'trash', and whining to themselves about how much they pay in taxes (While the really rich people pay even less in taxes- And they'll gladly pay a lawyer a lot of money to save the same amount in taxes, since that has advatages..).
-Kysh
Re:Your review is inaccurate as well...
on
Review: U-571
·
· Score: 2, Insightful
Point one...
> Target Motion Analasys... AKA TMA was introduced into the submarine service in the > early 1930s based on passive sonar analisys. This is how modern submarines shoot at > eachother, as well as how modern submarines shoot at surface combatants. Its pretty > simple, hear the target, track the target to find course and speed (and through > triangulation its range) and shoot torpedo at target. However, if the target shoots at > you, simply turn your submarine and fire at the bering where the torpedo origniated > (aka snapshot).
Respectfully, you have no idea what you're talking about. The ENTIRE computation, tracking and release system on world war II submarines was based on surface ships. Depth control on submarine torpedoes in those days was specifically to change the impact depth of the torpedos, not to be able to hit a submerged target.
The hydrophone operator may have been extremely good at what he did, and may have managed to narrow down the contact bearing during that sequence, but second world war JP/QB/QC has no depth determination. All 'sonar analisys' on second world war subs was done by the sonarman, whose bearings, prop RPM count (Done manually, by the way, with an optional definition filter for propcount reading) were fed into the TDC. While I don't doubt that modern submarines have the capability for doing the sort of analisys you mentioned, even in the peak of second world war submarine technology, nobody even considered firing upon a submerged contact.
Here's a little example: Submarine #1 (Our submarine):
Depth: 48 ft
Heading: Assume 220
Heavy negative trim, planes negative angle
Nose tank, MBTs, safety tank (Or equivilant) flooded
Motors engaged at ahead full
Torpedo in the tube (!?), firing controls on manual, no solution on the TDC.
Submarine #2 (The enemy sub):
depth: ~30' (Ostensibly having just fired a torpedo to sink the US sub)
Heading: Assume 180
Trim: Neutral, planes neutral
Sonarman: Has screw/dive and trim noises at 000 bearing (Second world war sonar was STRICTY TWO DIMENSIONAL, JP/QB/QC. (Not including depth sounder))
Motors ahead 2/3.
Now, somehow the crew of Submarine #2 loads a torpedo in the tube, confirms 000 bearing to target (Estimated- Remember, we have one sub sinking/flooding RIGHT BESIDE the submerging submarine's dive, and no idea what the other submarine is doing relative to depth or heading).
With no solution laid into the TDC, gyros not set on the torpedos, we're expected to believe that the crew of #2 magically guessed the depth and disposition of #1 and set the torpedo run depth and fired.
Ok, so that torpedo misses. What a shock.
Now, the movie would have me believe that submarine #1, whose sonar operator is alertly proclaiming the torpedo to have missed, turns the soundheads towards Submarine #2 to get a relative bearing (Remember we only have one sonarman), switches on the filters to narrow it down from the 20 degree spread detectable in flat mode, and gets an accurate bearing (WHILE THE SUB IS TURNING TO STARBORD).
Let's assume the torpedo is magically set to the appropriate depth).. Ok, so the diving officer is going crazy recovering a boat rigged heavily negative, while trying to maintain trim as the boat is being turned hard a-starboard.
All this stuff is fairly easy on modern subs, and all of it is 100% manual on WWII subs.
Now, with no course, only a guesstimated relative bearing for a bowshot on a closing submarine, whose screws are well shielded by her hull, relative to the soundheads on sub #1, sub #1 fires a torpedo which magically happens to strike (Even though our torpedos are supposed to magnetically detonate) the conning tower (Sail is the terminology for modern subs, I'm sure, but second world war subs had 'conning towers', which was water-tight structure above the control room, and sharing almost all functions with the control room, in case the conning tower became flooded), and sub #2 sinks.
If you don't see a problem with this scenario as clearly as I do at this point, you're no submariner.
Let me spell it out: In WWII, torpedos were gyro controlled (Not wire controlled or computer controlled, as in modern subs), had only rudimentary depth controls to determine where they struck a surface vessel, were not designed for any use other than torpedoing a surface vessel from a depth between persicope depth and surfaced, and were magnetically detonated.
The JP/QB/QC (Sonar) on WWII subs was in no way capable of analizing anything but bearing- It's simply designed to track in two dimensions, not three. The hydrophones were controlled by the sonarman, and are highly directional. The amplifiers in WWII subs have various filters to narrow a search and increase the gain for a more precise bearing, but are relatively slow in general.
In other words, the entire scenario is completely impossible.
> Point two: The torpedo did not hit the conning tower (actually called the "Sail" on a > submarine). It hit the hull below the waterline under the sail.
I've never heard anyone use the term 'waterline' in reference to a submerged submarine.
> Point three: Do you want to sit through 45 minutes of torpedo in the water?
45 minutes is a very long torpedo run.
> Now lets figure that a submarine can move (in WWII) at a max speed of ten knots > submerged. A torpedo in WWII could move at approximately 30 knots submerged. That > means that the torpedo is moving at about three times the speed of the submarine. > Using the 3 minute rule, a torpedo travels 3000 yards in three minutes. That is 1.5 > nautical miles. Not a bad distance in three minutes. The submarine (if turned > completely 180 degrees) traveling at full speed could only move 1000 yards ( 1/2 NM). > Not too good.
What, on earth, does this have to do with anything?
> Point four: There are some inaccuracies, but give hollywood a break to some degree. > Sheeze.
Why would I give Hollywood a break? The guy claimed to be an 'expert' in WWII submarines, and the movie was the most inaccurate I've ever seen in my life. It made me almost physically nauseous.
-Kysh
Re:Your review is inaccurate as well...
on
Review: U-571
·
· Score: 1
> However, historically it is fairly accurate if you remember that it is FICTION.
Accurate??? I'm astounded you say that, as an 'x submariner' yourself, whatever that means.
The U-571 somehow manages to torpedo another submarine, while both are submerged.
When the torpedo struck the other submarine, it punched all the way in to, and crumpled, the conning tower, before exploding.
Average torpedo run time in this movie was 6 seconds.
Just about every technical detail about both submarines was contrived and inaccurate.
I could come up with a list of inaccuracies about ten miles long here. This was by far the least technically accurate submarine movie I've ever seen, and that's saying something. Even giving it more credit than it deserves as a movie and saying, "As a movie, it was alright.", the technical inaccuracies were so horrible and obvious that any value the movie might of had was negated.
I don't want to defend the original reviewer, as the review was quite a bit over-the-top, but in general, he was correct.The movie was awful, inaccurate, poorly done, contrived, overplayed, undercooked, and Just Plain Dumb.
> The issue is in blocking sites that have nothing
> to do with spam, just because they happen to use
> the same ISP and some bastard decides "If
> i go overboard and block everything then
> they'll surely listen to me!"
The RBL is, in addition to a reverse map, also
distributed as a BGP table. Above.net, being run
in association with the ISC/MAPS/etc, takes a
strong position against spam. Therefore, it's
only logical for them to blackhole traffic to
a RBL'd network- In essence, they're saying,
'We will not accept traffic from spammers or
friends'
Think about it this way- The end user doesn't
'see' the benifit of the RBL, in the same way
that the end user doesn't 'see' the benifit of a
sysadmin at all- If the sysadmin and the RBL do
their jobs effectively, nobody notices- And that's
considered a good thing! Any attention at all is
likely to be negative.
> It's easy to block SMTP rather than blackhole
> all traffic. It's easy to block the offending
> IP address instead of an entire class C. I
> fail to see the point of your rant.
Well, last thing's first, it wasn't a rant- More
of a plea for understanding. Nobody 'blocked'
anyone. Above.net blackholed all traffic to an
RBL'd address. The RBL, to work, must make it
sufficiently painful to the spammers in question,
while remaining apolitical.
The RBL, if you read what it stands for, blocks
not only mailservers, but any entities that spam,
promote spam, or even ISPs that don't take action
against spam from their networks.
It's a behavior alteration system, not a
MMMMMMM-IM-NOT-LISTENING-MMMMMM passive system.
In my mind, the actions of the RBL are wholly
justifiable by the enormity of the spam problem.
The biggest problem is that nobody sees it because
the work is being done behind the scenes. But
just like an angry manager thinking that a
sysadmin is overpayed and lazy because they see
nothing happening, the public can far too easily
turn its venomous teeth to the task of hating the
RBL. It's the spam you DON'T see that you should
be thankful for.
I use Abovenet. And I have no problem with them
using BGP blackholing of RBL sites, at all.
I fully support that. Less spam for me, for one.
For two, I fully support the efforts of the RBL,
and know that only struggle and effort on the
part of system and network admins like me, against
the voices of the idiot users who don't see the
full picture, keeps the world as spam-free as it
is. Spammers are winning the battle- They are the
enemy, not the MAPS people, who are providing a
service, and dare I say, a damned fine service,
to the system and network administrators that are
intelligent enough to use it.
Even worse than the spammers are the people who
support spammers and spamming in general, and
the end users who just write off spam as a necessary evil. It is NOT, but if you give up on
anti-spam measures, all is already lost.
> The P-3 may be a patrol plane, but the EP-3E is
> a spy plane.
No, the 'EP-3E' is a surveillance model of a P-3.
They are the SAME AIRPLANE with a different
mission configuration. They are not at all for
use in any sort of covert operation (Which 'spy'
entails).
Basically, the P-3 surveillance is being used to
supplement our LEO satellites. But that doesn't
make it a 'spyplane'.
If you don't agree with this statement, then
you are merely arguing semantics.
> The Chinese state that we were in their airspace
Yes, they are lying. The incident wasn't even
vaguely close to the Chinese airspace.
>and that we made a sharp turn off course to hit
>their plane.
That's basically like the Exxon Valdez running
down a jetski, and about as likely.
> Do you really think we would be on autopilot
> flying so close to another plane?
Yes, most likely there was an GPS/INS FMS system
engaged during the operations part of the mission.
When intercepted (Yes, there are rules regarding
aerial intercept, standard signals, etc), the
intercepting aircraft are responsible for
maintaining seperation, in addition to the
standard right-of-way rules. (Less maneuverable
has the right-of-way, ergo, the P3)
Hence, there would have been no reason to
disengage the autopilot in response to an aerial
intercept.
> The likely story - both sides were playing a
> dangerous game of chicken in the air and
> collided.
This is a commonly expressed statement. However,
it is also highly unlikely. The P3 is not a 'spy
plane', as it's continually dubbed. It was built
in the 1950s- It's a military conversion of the
Lockheed Elektra, and its primary duty is ASW.
We use a few of them for electronic surveillance,
since the ASW (Anti-Submarine Warfare) mission is
less critical, and the conversion is easy.
You don't play 'a game of chicken' in an airplane
that large. You sit there and hope that the other
airplanes go away. Or at least stay safely on your
wing (As intercept rules dictate- Also, they
dictate that the intercept should be broken off
if it becomes unsafe for any reason).
No, the word 'Veer' doesn't adequitely describe
the maneuvering of a P3 (Also now used as an
aerial firefighter, in addition to military roles)
.. No, a more appropriate term is 'lumber'.
> The Chinese state that we were in their airspace
Yes, they are lying. The incident wasn't even
vaguely close to the Chinese airspace.
> and that we made a sharp turn off course to hit
> their plane.
That's basically like the Exxon Valdez running
down a jetski, and about as likely.
> Do you really think we would be on autopilot
> flying so close to another plane?
Yes, most likely there was an GPS/INS FMS system
engaged during the operations part of the mission.
When intercepted (Yes, there are rules regarding
aerial intercept, standard signals, etc), the
intercepting aircraft are responsible for
maintaining seperation, in addition to the
standard right-of-way rules. (Less maneuverable
has the right-of-way, ergo, the P3)
Hence, there would have been no reason to
disengage the autopilot in response to an aerial
intercept.
> The likely story - both sides were playing a
> dangerous game of chicken in the air and
> collided.
This is a commonly expressed statement. However,
it is also highly unlikely. The P3 is not a 'spy
plane', as it's continually dubbed. It was built
in the 1950s- It's a military conversion of the
Lockheed Elektra, and its primary duty is ASW.
We use a few of them for electronic surveillance,
since the ASW (Anti-Submarine Warfare) mission is
less critical, and the conversion is easy.
You don't play 'a game of chicken' in an airplane
that large. You sit there and hope that the other
airplanes go away. Or at least stay safely on your
wing (As intercept rules dictate- Also, they
dictate that the intercept should be broken off
if it becomes unsafe for any reason).
No, the word 'Veer' doesn't adequitely describe
the maneuvering of a P3 (Also now used as an
aerial firefighter, in addition to military roles)
.. No, a more appropriate term is 'lumber'.
The transponder replies to interrogation by secondary radar. Not all transponders are capable
of mode-C (Altitude encoding) operation.
Many aircraft don't even have transponders.
Quite a few don't even have radios.
Without a transponder, capable of mode-C, unless
in PAR (Precision Approach Radar, available only
in some airspace environments, and only on the
approach environment (And almost always in
airspace you wouldn't be without mode-C anyway))
coverage, your altitude won't show up at all. And
altitude reported is not allowed to be relied on
by ATC. ATC must maintain lateral seperation. They
cannot stack returns. If returns touched, they
would be in some serious trouble. And piles of
paperwork.:>
Argh.. you're not a pilot, are you?
Be terrified: There are A LOT of airplanes out
there flying above you that are Not controlled by
ATC. Infact, they're being controlled by, horror
of horrors, the pilots. Didn't you see
Independance Day?? Do you know what can happen if
the PILOT is actually allowed to fly? Wow.
On a more serious note, there's a lot more to
flying than travel. Air traffic control isn't like
a traffic cop, air traffic control provides
traffic coordination, seperation, and above all,
assistance to pilots. They do not make the rules,
they follow the rules and assist pilots as those
rules require. They're a cool bunch, though.
But if air traffic control didn't exist, traffic
would still be manageable.
From the passenger's point of view, I guess I can
see where you're coming from.. but it's not an
educated point of view. If you want real answers,
ask a pilot, or even an air traffic controller.
Don't ask/.ers.:>
Because inertial navigation systems are based on
technology like calibrated laser-ring gyros, and
cost a great deal of money to install and
configure. They rely on vastly more expensive
avionics, as well. They are internal, but must be
set before flight.
GPS works fine. Heck, VOR/ADF/DME works great.
Even dead reckoning works well, too. Radar is
good, Loran-C is functional, and you can certainly
never have enough navigational capacity.
It's amazing reading the reactions of the general
public to stories like this. If people knew how
things really worked, they'd pee their pants every
time they flew on a commercial airliner.;>
It's the pilots, not the equipment, that keeps you
alive. Remember that, and respect them.:>
If you're running 2x400Mhz w/4 or 8M ecache, it is possble. This is not what I would consider a likely layout for a Netra, however.
I have had/zero/ problems with anything Netra from sun, except the Netra T1. The T1 is a great
machine, for what it does.. the very first shipments had a few problems, but Sun was very responsive, and I have not had a problem since. (We were a customer for a few batches at the very beginning, one of the first people to use the T1)
Regardless, Sun is very, very careful with telco-grade servers, so it's likely that even if you do have this problem, the machine won't fall back to prom.
This issue is a bit overblown. Sun hardware is, without a doubt, one of the most stable platforms I've ever seen. They do have some problems with some models, sometimes. Most problems you ever see with a Sun are related to environmental conditions. Specifically, heat. If you keep a Sun machine in a datacenter and don't exceed 75F (And provide adequate ventilation so that the systems (And any disk arrays) don't get trapped in their own hotspot), you will see hardware problems with excruciating infrequency.
As a sr solaris sysadmin, who has worked on Sun boxes for years, I have/nothing/ but praises for Sun service and support. Sun QA is top-notch, in comparison to the rest of the tech industry. I got my start in Linux, and still use it a great deal. At home, all but three of my boxes run Linux, including several PCs and a Sun 670MP. I also use various BSDs. Pretty much, so long as it's Unix, it's ok by me. Bearing this in mind, realize that I am capable of obejctive, honest review. Sun has done more for the free software community than anyone therein seems to want to acknowledge, even though they are threatened by Linux. They are a large company, and do have their share of corporatism, but they also get an unfairly bad rap in the Linux community, for reasons I do not comprehend. Sun hardware has always been the industry standard for rock-solid reliability, and IO bandwidth. They never have been the blazing speed machines. Going back to Ebay, where people were asking whether this was a problem with the cache (It is not a RAM issue, but an issue with the cache on the 400Mhz UltraSparc II processors, and I have/never/ seen it outside of 2x400 configuration in an Ultra II).. It wasn't. Ebay was a victim of bad sysadmins. Perhaps they were very good sysadmins, who had no idea of what to do with an E10k. Perhaps management made the decision for them. (This happens with eerie regularity) The fact of the matter is, the E10k is not a 'super-processing-power' box. It's a 'IO pumping, high-availibility' box. The sysadmins at Ebay had the E10k running flat out, not partitioned (As they're meant to be run) in quadrants. They grew so fast that they put the other E10k into production in the same fashion, instead of using it as a hot standby. Each E10k was a single point of failure, with the ability to be multiply redundant internally removed. A single problem with an OS that wasn't even officially supported on the E10k running at an invalid patchlevel caused a very highly publicised downtime. Instead of blaming bad setup (Which would be disasterous for investor relations), Ebay blamed Sun.
As to the latter part of this article, I know nothing about Sun covering up that problem, (Which I have seen before), but don't deny that Sun, being a big corporation, might do such things, as all corporations are wont to do, even the ones very popular in the Linux community. Usually that problem manifests itself in the system log long before any problem is ever seen. This problem is also listed on Sunsolve. Sunsolve is one of the most open policies I've ever seen to system-related issues. The only group of people that even come close to that level of support is Debian.
While I know this was rather long-winded and might generate lots of flames, I do mean it. Don't bash Sun summarily, and don't bash Sun on QA. It's like talking about raising "Serious questions about Honda QA" if Honda issued a recall for defective OEM tires (A year after the vehicles with those tires were issued). Almost nobody would think to bash Honda QA over a single issue. Sun may have had a few quality issues from time to time, but so does everyone. And at least Sun is actually saying something, unlike companies that deny forever.
Why bash Sun, and not Intel - Another/. headline for today.
> My fibre optic fractional T1 opened the edit > page in less than a second. It took about 3 > seconds to load the list of comments ranked over > '2' but that was mostly CPU usage.
> >... didn't happen, and stop spreading the rumor > that it did... >
Hotmail did, indeed, try to migrate to NT. Two things happened: 1. The engineers they hired to do the move said that it could not be done, and that the systems just could not stand up to the load. 2. The Unix admins threatened to quit on the spot if they continued to threaten to move Hotmail to NT. All of Microsoft's significant ISP services (Hotmail and WebTV, of note) run on Solaris. Hotmail uses some FreeBSD. Linux and FreeBSD, as well as NT, comprise some of the tools people use on the backend for development and such, but the infrastructure of both sites is primarily Solaris.
Note that all this information can be found easily by public means, so I'm divulging no information by saying this.
Aircraft navigational systems vary in frequencies and sensitivity. The real headache here could be for a category IIIa ILS approach. The localizer will use something in the 108-114Mhz range, but the glideslope is UHF. Instruments like the ADF are sensitive to any strong (And some weak) electronic signal, and will swing to point to the strongest source of RF emissions that pass its filters. Won't necessarily be a cellphone, but you never know. For me, a more convincing reason never to use Cellular phones, or allow any passenger of mine to do so would be:
As per FAR (15 CFR) 121.305: (a) Except as provided in paragraph (b) of this section, no person may operate, nor may any operator or pilot in command of an aircraft allow the operation of, any portable electronic device on any U.S.-registered civil aircraft operating under this part. (b) Paragraph (a) of this section does not apply to-- (1) Portable voice recorders; (2) Hearing aids; (3) Heart pacemakers; (4) Electric shavers; or (5) Any other portable electronic device that the part 119 certificate holder has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used.
And per 91.21: (a) Except as provided in paragraph (b) of this section, no person mayoperate, nor may any operator or pilot in command of an aircraft allow the operation of, any portable electronic device on any of the following U.S.- registered civil aircraft: (1) Aircraft operated by a holder of an air carrier operating certificate or an operating certificate; or (2) Any other aircraft while it is operated under IFR. (b) Paragraph (a) of this section does not apply to-- (1) Portable voice recorders; (2) Hearing aids; (3) Heart pacemakers; (4) Electric shavers; or (5) Any other portable electronic device that the operator of the aircraft has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used. (c) In the case of an aircraft operated by a holder of an air carrier operating certificate or an operating certificate, the determination required by paragraph (b)(5) of this section shall be made by that operator of the aircraft on which the particular device is to be used. In the case of other aircraft, the determination may be made by the pilot in command or other operator of the aircraft.
I'm from the south, I have a southern accent. My grammar is better than 90% of the people I speak with or talk to online. English is my first language.
About accents, regional accents are not a sign of culture. They're a sign of region. --- > And the way some people in the US mangle words > such as internet (inner-net), roof (ruff) and, > route (rout) and many other words.
-Incomplete sentence.
-Sentence begun with conjunction.
-Proper pronunciation of 'Router' (Such as Cisco) is 'Rowter' (Monosyllabic). I almost laughed my tail off the other day when I heard a canadian pronounce it 'rooter'. A 'Rooter' is something used to pull up weeds. See 'roto-rooter'.
-Canadians talking about stupid accents are being pure hypocrites. All accents are stupid, if one is prejudiced against people from the region of origination.
* 'Class A' is obsolete terminology. * Portable netblocks could be pretty much anywhere * Below a/24, netblocks are not often SWIP'd, even though it's possible to piece out smaller bits of that netblock to pretty much any locale * Dynamically checking the assignments of netblocks from a whois against arin (whois -h whois.arin.net) is possible, but painful. Not to mention that you'd have to find an easy way to interpret the data you got back. And what happens if you have a major US backbone that services.ca, but retains SWIPs of their netblocks? You're f*@d.
Slashdot Mirror
> One of the most impressive things I've seen a
;>
> Raptor do so far (on Discovery Wings, of course,
> heh) is fly backwards... jet is flying straight
> and level, pilot pulls the throttle all the way up
> and the jet actually goes into a "controlled
> stall" and moves backwards (or so it appears
> visually) for a short distance. Hell if I know if
> it's useful in combat -- but nifty to the
> layperson.
Perhaps. I've seen my flight instructor doing the
same thing in a 1939 Piper Cub (SuperCub with a
bigger engine) while towing banners. He'd fly into
a strongish headwind down the beach, and ride the
stall at somewhere around 32mph. Depending on the
wind speed, he'd either be hovering or flying
backward.
For the F-22 to perform the same stunt, the
aircraft would have to be either flying against
the jet stream at stall speed, or they'd have to
go into a ballistic attitude, 'sitting on the
jets', and use the vectored thrust to move
backwards as well as staying aloft.
Of course, for the difference in price, I'll take
the cub anyday.
-Kysh
> In what way is Ada better than Java in this
:>
> respect? I only know a little about Ada, so this
> is a serious question. My understanding is that
> Ada and Java have very similar safety goals
> (especially with respect to exceptions) so I'm
> curious about what you think Ada gets right and
> Java gets wrong.
Let me be fair.. as a language, I'm not terribly
familiar with java. I have spent a great amount of
time supporting Java developers on the system
level, however. I have seen developers write java
code that crashes in very gnarly ways, and had to
support them. I've seen java interpreters just
spontaneously die. Now this could certainly be
buggy implementations, and not a bad language
specification. While that was not the impression I
was given by the developers in question, I don't
deny the possibility. I have, personally, never
seen an Ada program 'crash'. I have never seen an
Ada program exit in any way other than an
unhandled exception or a normal exit. I've seen
Java do a lot worse.
I will not say that java, as a specification, is
less 'safety critical' than Ada, only that I am
not aware that it is as much so. If the
implementation is the problem, as I mentioned that
it could be above, then pending better
implementations, I'll check back in with this
topic.
In closing, though, I have to say that, from the
information I have, an Ada program is about a
billion times more reliable than a Java program,
when you're talking about large (Or huge)
applications. Ada also has the benefit of a big
experience base, mathematical analysis, review,
etc.
I'm open to comments regarding Java
implementations, stability, and the
safety-critical methodologies present (Or lacking)
in Java from those more familiar with the
language.
Respectfully,
-Kysh
> This means the developers were forced to use
> Ada, but why ? To me, it seems some suits think
> it's especially "safe" for some reason, does
> anyone know more about that ?
Ada is especially safe. It is, in fact, one of the
VERY few safety critical environments you will
find. It's very simple- A safety critical program
must never exit and give up control functionality
entirely, no matter what happens. There are many
things that you can do with C/C++/Java that will
cause a crash unrecoverable by the system.
Ada is designed to inherantly prevent a programmer
who follows the appropriate standards from writing
a program that can just crash and exit. As long as
every possible exception has a handler, an Ada
program can be written that will not crash.
> But I think you can try to make a programming
> language as "safe" as you want, it won't prevent
> you from implementing bugs, it just causes a
> false sense of safety instead which can be even
> more dangerous, IMHO.
Bugs are universal. But bugs in a C program can
cause the controlling system to shut it down with
prejudice (Sig 11 and others), and it doesn't
offer the automatic safety nets Ada does. Can you
write safety critical software in C/C++/Java?
Certainly. It's all a matter of methodology. Ada
enforces the methodology, which is why people hate
it. They can't do cute, horrible hacks like they
can in C/C++, and Ada requires explicit
specification.. Ada has specific standards of
implementation for software, and a good inherant
design. It is designed, from the ground up, as a
'safety critical' language, and for the most part
succeeds on its own merit.
I do understand the widespread animosity towards
Ada. People don't like the verbose, very specific
code. Progammers often want to bend the langauge
over their knees and perform horrid hacks that
make reasonable people blanch in fear, but Ada
doesn't really allow that. Programmers are often
forced to learn Ada in structured learning
courses, and forced to read the Ada RM. They end
up hating it because of the language and
terminology used, because of the verbosity of the
language, because of some of the difficult
concepts of Ada, etc..
But it really is a fine language. (I'm sure many
people will disagree with me without really having
an objective or informed viewpoint, but that's
just how it goes)
-Kysh
> Sorry, but if you have to reboot the ENTIRE
.--.
:>
:>
:>
> avionics system of a F-22 you're fucked to say
> mildly.
Avionics and flight control systems are separate
and extremely disparate.
> This plane is always in a controlled stall,
That is extremely unlikely. A stall is defined as
a condition when the wing exceeds the critical
angle of attack (Which is in turn defined as the
angle of attack where the airfoil is no longer
producing lift, but is instead experiencing
separated and turbulent airflow).
|
| / \
Cl | /
1| /
| /
| /
| /
|/
+--------------
0 5 10 15 20
AOA (Degrees)
Is a typical graph depicting Cl (Coefficient of
Lift) and its relation to Angle of Attack. Lift
(And induced drag) increases with an increase of
angle of attack or an increase in speed.
Angle of Attack, for your reference, is defined as
the angle between the chord line and the relative
wind. The chord line of an airfoil is an imaginary
line connecting its leading edge with its trailing
edge.
The 'Relative wind' is defined as the flight path
of the aircraft.
Therefore, for an airplane to be flown perpetually
in a state of controlled stall, its airfoil would
always be pitched up at approximately 17 degrees
relative to the flight path of the airplane.
Would be quite funny to watch, actually.
There's a lot of misunderstanding about 'stalls'
out there. What the F-22 may be able to do better
than more 'conventional' airplanes, and perhaps
that to which you refer, is ride the edge of an
impending stall (In a high speed, hard banked,
high-G turn, for example) without diverging from
controlled flight.
I for one don't care for fly-by-wire. Perhaps I'm
old fashioned.
I'd rather the airplane do what I told it to do
than what it thinks I should have told it to do.
Same reason I like Unix- I don't want my airplane,
or my computer, doing what it thinks I meant
rather than what I told it.
-Kysh
While I think your points aren't terribly coherent, and the structure and grammar of your post isn't great, the point you make is excellent, I think.
I do agree with your assesment overall.
The problem is, many of the people who disagree with you don't understand poor. They come from nice well-off parents in nice little neighborhoods in nice parts of town. They may even think of themselves as 'impovrished' since they never got that Atari 2600, Commodore PET, Amiga or Nintendo they wanted, when 'all their friends had one', or maybe their parents had to drive a *Gasp* used car.
They may have even not been fully funded for the college of their choice by their parents (What a horror!).
No, most of the dissenters probably think, "Look at me! I'm making all this money, and I had to go to college for eight long years to get where I am. I even had to take a minimum wage job when I was in college- I was a poor college student! I know poverty! And look what I made of myself."
I know this, because I've had this debate with many people, and they truly see it that way. They don't realize that poverty- The sort of poverty in which a MAJORITY of Americans live, is the sort of poverty where you work two jobs and your spouse works one, so you can make ends meet enough to hopefully own a house of your own before you die.
It is the sort of poverty where there is no Martha Stewart Osterizer Plus in the kitchen- Where you instead have to balance buying food with taking little Amy to the doctor to see about her constant, wracking cough (since neither of your jobs offers health insurance).
It's the kind of poverty where you don't cry because you can't get the Lexus and have to settle for the Honda, but instead feel lucky to have found the $200 Toyota that's got 260k miles and is rusted out with no heat, much less radio.
Oh wait, I forget- The dissenter would say, "Driving is a privelege, not a right and if they can't afford to drive, they should walk!'
Walk, should they? Or maybe take the bus? When they have to get their kids to school, get to job
one, get home in time for a quick dinner before heading to job two, and get back home for a few hours' sleep, walking or bussing might easily take another three hours.
And what happens when they find out that Amy has been living with an upper respiratory infection, and has heavy scarring in 35% of her lungs which has led to a serious case of bacterial pneumonia
taking hold. Amy needs to stay overnight at the hospital, a fluid IV ($90 per litre of glucose cocktail with antibiotic, changed bi-hourly, $50 disposable IV needle, $45 solution container, $20
tubing, $5 tape), blood tests ($15 syringe/needle, $600 haemogram), etc etc, and the final bill comes to well over $1,500.
Stuff happens. And when stuff happens, and money is short, things can get really bad.
Poverty is a pit with slippery-sloped sides that is very difficult to pull yourself out of. It is not a lack of intellect (Some of the sharpest people I know were poor), nor a lack of work ethic- Do those who dissent really think that they, with their 8-5 manager job are working harder than Joe down the street at the tire place?
Ah well, this has turned out much longer than I intended initially, but I hate seeing people with no real concept of what 'poverty' is talking amongst themselves about how superior they are to the lazy, shiftless, stupid poor 'trash', and whining to themselves about how much they pay in taxes (While the really rich people pay even less in taxes- And they'll gladly pay a lawyer a lot of money to save the same amount in taxes, since that has advatages..).
-Kysh
Point one...
> Target Motion Analasys... AKA TMA was introduced into the submarine service in the
> early 1930s based on passive sonar analisys. This is how modern submarines shoot at
> eachother, as well as how modern submarines shoot at surface combatants. Its pretty
> simple, hear the target, track the target to find course and speed (and through
> triangulation its range) and shoot torpedo at target. However, if the target shoots at
> you, simply turn your submarine and fire at the bering where the torpedo origniated
> (aka snapshot).
Respectfully, you have no idea what you're talking about.
The ENTIRE computation, tracking and release system on world war II submarines was based on surface ships. Depth control on submarine torpedoes in those days was specifically to change the impact depth of the torpedos, not to be able to hit a submerged target.
The hydrophone operator may have been extremely good at what he did, and may have managed to narrow down the contact bearing during that sequence, but second world war
JP/QB/QC has no depth determination. All 'sonar analisys' on second world war subs was done by the sonarman, whose bearings, prop RPM count (Done manually, by the way, with an optional definition filter for propcount reading) were fed into the TDC. While I don't doubt that modern submarines have the capability for doing the sort of analisys you mentioned, even in the peak of second world war submarine technology, nobody even considered firing upon a submerged contact.
Here's a little example:
Submarine #1 (Our submarine):
flooded
manual, no solution on the TDC.
Submarine #2 (The enemy sub):
STRICTY TWO DIMENSIONAL, JP/QB/QC. (Not including depth sounder))
Now, somehow the crew of Submarine #2 loads a torpedo in the tube, confirms 000 bearing to target (Estimated- Remember, we have one sub sinking/flooding RIGHT BESIDE the submerging submarine's dive, and no idea what the other submarine is doing relative to depth or heading).
With no solution laid into the TDC, gyros not set on the torpedos, we're expected to believe that the crew of #2 magically guessed the depth and disposition of #1 and set the torpedo run depth and fired.
Ok, so that torpedo misses. What a shock.
Now, the movie would have me believe that submarine #1, whose sonar operator is alertly proclaiming the torpedo to have missed, turns the soundheads towards Submarine #2 to get a relative bearing (Remember we only have one sonarman), switches on the filters to narrow it down from the 20 degree spread detectable in flat mode, and gets an accurate bearing (WHILE THE SUB IS TURNING TO STARBORD).
Let's assume the torpedo is magically set to the appropriate depth)..
Ok, so the diving officer is going crazy recovering a boat rigged heavily negative, while trying to maintain trim as the boat is being turned hard a-starboard.
All this stuff is fairly easy on modern subs, and all of it is 100% manual on WWII subs.
Now, with no course, only a guesstimated relative bearing for a bowshot on a closing submarine, whose screws are well shielded by her hull, relative to the soundheads on sub #1, sub #1 fires a torpedo which magically happens to strike (Even though our torpedos are supposed to magnetically detonate) the conning tower (Sail is the terminology for modern subs, I'm sure, but second world war subs had 'conning towers', which was water-tight structure above the control room, and sharing almost all functions with the control room, in case the conning tower became flooded), and sub #2 sinks.
If you don't see a problem with this scenario as clearly as I do at this point, you're no submariner.
Let me spell it out: In WWII, torpedos were gyro controlled (Not wire controlled or computer controlled, as in modern subs), had only rudimentary depth controls to determine where they struck a surface vessel, were not designed for any use other than torpedoing a surface vessel from a depth between persicope depth and surfaced, and were magnetically detonated.
The JP/QB/QC (Sonar) on WWII subs was in no way capable of analizing anything but bearing- It's simply designed to track in two dimensions, not three. The hydrophones were controlled by the sonarman, and are highly directional. The amplifiers in WWII subs have various filters to narrow a search and increase the gain for a more precise bearing, but are relatively slow in general.
In other words, the entire scenario is completely impossible.
> Point two: The torpedo did not hit the conning tower (actually called the "Sail" on a > submarine). It hit the hull below the waterline under the sail.
I've never heard anyone use the term 'waterline' in reference to a submerged submarine.
> Point three: Do you want to sit through 45 minutes of torpedo in the water?
45 minutes is a very long torpedo run.
> Now lets figure that a submarine can move (in WWII) at a max speed of ten knots
> submerged. A torpedo in WWII could move at approximately 30 knots submerged. That
> means that the torpedo is moving at about three times the speed of the submarine.
> Using the 3 minute rule, a torpedo travels 3000 yards in three minutes. That is 1.5
> nautical miles. Not a bad distance in three minutes. The submarine (if turned
> completely 180 degrees) traveling at full speed could only move 1000 yards ( 1/2 NM).
> Not too good.
What, on earth, does this have to do with anything?
> Point four: There are some inaccuracies, but give hollywood a break to some degree.
> Sheeze.
Why would I give Hollywood a break? The guy claimed to be an 'expert' in WWII submarines, and the movie was the most inaccurate I've ever seen in my life. It made me almost physically nauseous.
-Kysh
Accurate??? I'm astounded you say that, as an
'x submariner' yourself, whatever that means.
submarine, while both are submerged.
it punched all the way in to, and crumpled, the
conning tower, before exploding.
seconds.
submarines was contrived and inaccurate.
I could come up with a list of inaccuracies about
ten miles long here. This was by far the least
technically accurate submarine movie I've ever
seen, and that's saying something.
Even giving it more credit than it deserves as a
movie and saying, "As a movie, it was alright.",
the technical inaccuracies were so horrible and
obvious that any value the movie might of had was
negated.
I don't want to defend the original reviewer, as
the review was quite a bit over-the-top, but in
general, he was correct.The movie was awful,
inaccurate, poorly done, contrived, overplayed,
undercooked, and Just Plain Dumb.
-Kysh
.. But perhaps it might be interesting to some?
http://www.lapdragon.org/~kysh/losebattle.html
-Kysh
> The issue is in blocking sites that have nothing
> to do with spam, just because they happen to use
> the same ISP and some bastard decides "If
> i go overboard and block everything then
> they'll surely listen to me!"
The RBL is, in addition to a reverse map, also
distributed as a BGP table. Above.net, being run
in association with the ISC/MAPS/etc, takes a
strong position against spam. Therefore, it's
only logical for them to blackhole traffic to
a RBL'd network- In essence, they're saying,
'We will not accept traffic from spammers or
friends'
Think about it this way- The end user doesn't
'see' the benifit of the RBL, in the same way
that the end user doesn't 'see' the benifit of a
sysadmin at all- If the sysadmin and the RBL do
their jobs effectively, nobody notices- And that's
considered a good thing! Any attention at all is
likely to be negative.
> It's easy to block SMTP rather than blackhole
> all traffic. It's easy to block the offending
> IP address instead of an entire class C. I
> fail to see the point of your rant.
Well, last thing's first, it wasn't a rant- More
of a plea for understanding. Nobody 'blocked'
anyone. Above.net blackholed all traffic to an
RBL'd address. The RBL, to work, must make it
sufficiently painful to the spammers in question,
while remaining apolitical.
The RBL, if you read what it stands for, blocks
not only mailservers, but any entities that spam,
promote spam, or even ISPs that don't take action
against spam from their networks.
It's a behavior alteration system, not a
MMMMMMM-IM-NOT-LISTENING-MMMMMM passive system.
In my mind, the actions of the RBL are wholly
justifiable by the enormity of the spam problem.
The biggest problem is that nobody sees it because
the work is being done behind the scenes. But
just like an angry manager thinking that a
sysadmin is overpayed and lazy because they see
nothing happening, the public can far too easily
turn its venomous teeth to the task of hating the
RBL. It's the spam you DON'T see that you should
be thankful for.
-Kysh
I use Abovenet. And I have no problem with them
using BGP blackholing of RBL sites, at all.
I fully support that. Less spam for me, for one.
For two, I fully support the efforts of the RBL,
and know that only struggle and effort on the
part of system and network admins like me, against
the voices of the idiot users who don't see the
full picture, keeps the world as spam-free as it
is. Spammers are winning the battle- They are the
enemy, not the MAPS people, who are providing a
service, and dare I say, a damned fine service,
to the system and network administrators that are
intelligent enough to use it.
Even worse than the spammers are the people who
support spammers and spamming in general, and
the end users who just write off spam as a necessary evil. It is NOT, but if you give up on
anti-spam measures, all is already lost.
-Kysh
> The P-3 may be a patrol plane, but the EP-3E is
> a spy plane.
No, the 'EP-3E' is a surveillance model of a P-3.
They are the SAME AIRPLANE with a different
mission configuration. They are not at all for
use in any sort of covert operation (Which 'spy'
entails).
Basically, the P-3 surveillance is being used to
supplement our LEO satellites. But that doesn't
make it a 'spyplane'.
If you don't agree with this statement, then
you are merely arguing semantics.
-Kysh
> The Chinese state that we were in their airspace
Yes, they are lying. The incident wasn't even
vaguely close to the Chinese airspace.
>and that we made a sharp turn off course to hit
>their plane.
That's basically like the Exxon Valdez running
down a jetski, and about as likely.
> Do you really think we would be on autopilot
> flying so close to another plane?
Yes, most likely there was an GPS/INS FMS system
engaged during the operations part of the mission.
When intercepted (Yes, there are rules regarding
aerial intercept, standard signals, etc), the
intercepting aircraft are responsible for
maintaining seperation, in addition to the
standard right-of-way rules. (Less maneuverable
has the right-of-way, ergo, the P3)
Hence, there would have been no reason to
disengage the autopilot in response to an aerial
intercept.
> The likely story - both sides were playing a
> dangerous game of chicken in the air and
> collided.
This is a commonly expressed statement. However,
it is also highly unlikely. The P3 is not a 'spy
plane', as it's continually dubbed. It was built
in the 1950s- It's a military conversion of the
Lockheed Elektra, and its primary duty is ASW.
We use a few of them for electronic surveillance,
since the ASW (Anti-Submarine Warfare) mission is
less critical, and the conversion is easy.
You don't play 'a game of chicken' in an airplane
that large. You sit there and hope that the other
airplanes go away. Or at least stay safely on your
wing (As intercept rules dictate- Also, they
dictate that the intercept should be broken off
if it becomes unsafe for any reason).
No, the word 'Veer' doesn't adequitely describe
the maneuvering of a P3 (Also now used as an
aerial firefighter, in addition to military roles)
.. No, a more appropriate term is 'lumber'.
> The Chinese state that we were in their airspace
Yes, they are lying. The incident wasn't even
vaguely close to the Chinese airspace.
> and that we made a sharp turn off course to hit
> their plane.
That's basically like the Exxon Valdez running
down a jetski, and about as likely.
> Do you really think we would be on autopilot
> flying so close to another plane?
Yes, most likely there was an GPS/INS FMS system
engaged during the operations part of the mission.
When intercepted (Yes, there are rules regarding
aerial intercept, standard signals, etc), the
intercepting aircraft are responsible for
maintaining seperation, in addition to the
standard right-of-way rules. (Less maneuverable
has the right-of-way, ergo, the P3)
Hence, there would have been no reason to
disengage the autopilot in response to an aerial
intercept.
> The likely story - both sides were playing a
> dangerous game of chicken in the air and
> collided.
This is a commonly expressed statement. However,
it is also highly unlikely. The P3 is not a 'spy
plane', as it's continually dubbed. It was built
in the 1950s- It's a military conversion of the
Lockheed Elektra, and its primary duty is ASW.
We use a few of them for electronic surveillance,
since the ASW (Anti-Submarine Warfare) mission is
less critical, and the conversion is easy.
You don't play 'a game of chicken' in an airplane
that large. You sit there and hope that the other
airplanes go away. Or at least stay safely on your
wing (As intercept rules dictate- Also, they
dictate that the intercept should be broken off
if it becomes unsafe for any reason).
No, the word 'Veer' doesn't adequitely describe
the maneuvering of a P3 (Also now used as an
aerial firefighter, in addition to military roles)
.. No, a more appropriate term is 'lumber'.
Thank you, finally someone says it. I've been trying to correct people on this constantly, but I'm just drowning in media-induced ignorance. -Kysh
The transponder replies to interrogation by secondary radar. Not all transponders are capable
:>
of mode-C (Altitude encoding) operation.
Many aircraft don't even have transponders.
Quite a few don't even have radios.
Without a transponder, capable of mode-C, unless
in PAR (Precision Approach Radar, available only
in some airspace environments, and only on the
approach environment (And almost always in
airspace you wouldn't be without mode-C anyway))
coverage, your altitude won't show up at all. And
altitude reported is not allowed to be relied on
by ATC. ATC must maintain lateral seperation. They
cannot stack returns. If returns touched, they
would be in some serious trouble. And piles of
paperwork.
-Kysh
Argh.. you're not a pilot, are you?
/.ers. :>
Be terrified: There are A LOT of airplanes out
there flying above you that are Not controlled by
ATC. Infact, they're being controlled by, horror
of horrors, the pilots. Didn't you see
Independance Day?? Do you know what can happen if
the PILOT is actually allowed to fly? Wow.
On a more serious note, there's a lot more to
flying than travel. Air traffic control isn't like
a traffic cop, air traffic control provides
traffic coordination, seperation, and above all,
assistance to pilots. They do not make the rules,
they follow the rules and assist pilots as those
rules require. They're a cool bunch, though.
But if air traffic control didn't exist, traffic
would still be manageable.
From the passenger's point of view, I guess I can
see where you're coming from.. but it's not an
educated point of view. If you want real answers,
ask a pilot, or even an air traffic controller.
Don't ask
-Kysh, a pilot.
Because inertial navigation systems are based on
;>
:>
technology like calibrated laser-ring gyros, and
cost a great deal of money to install and
configure. They rely on vastly more expensive
avionics, as well. They are internal, but must be
set before flight.
GPS works fine. Heck, VOR/ADF/DME works great.
Even dead reckoning works well, too. Radar is
good, Loran-C is functional, and you can certainly
never have enough navigational capacity.
It's amazing reading the reactions of the general
public to stories like this. If people knew how
things really worked, they'd pee their pants every
time they flew on a commercial airliner.
It's the pilots, not the equipment, that keeps you
alive. Remember that, and respect them.
-Kysh
If you're running 2x400Mhz w/4 or 8M ecache, it is possble. This is not what I would consider a likely layout for a Netra, however.
/zero/ problems with anything Netra from sun, except the Netra T1. The T1 is a great
:>
I have had
machine, for what it does.. the very first shipments had a few problems, but Sun was very responsive, and I have not had a problem since. (We were a customer for a few batches at the very beginning, one of the first people to use the T1)
Regardless, Sun is very, very careful with telco-grade servers, so it's likely that even if you do have this problem, the machine won't fall back to prom.
This issue is a bit overblown. Sun hardware is, without a doubt, one of the most stable platforms I've ever seen. They do have some problems with some models, sometimes. Most problems you ever see with a Sun are related to environmental conditions. Specifically, heat. If you keep a Sun machine in a datacenter and don't exceed 75F (And provide adequate ventilation so that the systems (And any disk arrays) don't get trapped in their own hotspot), you will see hardware problems with excruciating infrequency.
Be kind to your Suns.
-Kysh
As a sr solaris sysadmin, who has worked on Sun boxes for years, I have /nothing/ but praises for Sun service and support. Sun QA is top-notch, in comparison to the rest of the tech industry. I got my start in Linux, and still use it a great deal. At home, all but three of my boxes run Linux, including several PCs and a Sun 670MP. I also use various BSDs. Pretty much, so long as it's Unix, it's ok by me. /never/ seen it outside of 2x400 configuration in an Ultra II).. It wasn't. Ebay was a victim of bad sysadmins. Perhaps they were very good sysadmins, who had no idea of what to do with an E10k. Perhaps management made the decision for them. (This happens with eerie regularity)
/. headline for today.
Bearing this in mind, realize that I am capable of obejctive, honest review.
Sun has done more for the free software community than anyone therein seems to want to acknowledge, even though they are threatened by Linux. They are a large company, and do have their share of corporatism, but they also get an unfairly bad rap in the Linux community, for reasons I do not comprehend. Sun hardware has always been the industry standard for rock-solid reliability, and IO bandwidth. They never have been the blazing speed machines.
Going back to Ebay, where people were asking whether this was a problem with the cache (It is not a RAM issue, but an issue with the cache on the 400Mhz UltraSparc II processors, and I have
The fact of the matter is, the E10k is not a 'super-processing-power' box. It's a 'IO pumping, high-availibility' box. The sysadmins at Ebay had the E10k running flat out, not partitioned (As they're meant to be run) in quadrants. They grew so fast that they put the other E10k into production in the same fashion, instead of using it as a hot standby. Each E10k was a single point of failure, with the ability to be multiply redundant internally removed. A single problem with an OS that wasn't even officially supported on the E10k running at an invalid patchlevel caused a very highly publicised downtime. Instead of blaming bad setup (Which would be disasterous for investor relations), Ebay blamed Sun.
As to the latter part of this article, I know nothing about Sun covering up that problem, (Which I have seen before), but don't deny that Sun, being a big corporation, might do such things, as all corporations are wont to do, even the ones very popular in the Linux community. Usually that problem manifests itself in the system log long before any problem is ever seen. This problem is also listed on Sunsolve.
Sunsolve is one of the most open policies I've ever seen to system-related issues. The only group of people that even come close to that level of support is Debian.
While I know this was rather long-winded and might generate lots of flames, I do mean it. Don't bash Sun summarily, and don't bash Sun on QA. It's like talking about raising "Serious questions about Honda QA" if Honda issued a recall for defective OEM tires (A year after the vehicles with those tires were issued). Almost nobody would think to bash Honda QA over a single issue. Sun may have had a few quality issues from time to time, but so does everyone. And at least Sun is actually saying something, unlike companies that deny forever.
Why bash Sun, and not Intel - Another
-Kysh
> My fibre optic fractional T1 opened the edit
:>
> page in less than a second. It took about 3
> seconds to load the list of comments ranked over > '2' but that was mostly CPU usage.
Hmm, aren't 'fibre' and 'T1' contradictory?
-Kysh
> ... didn't happen, and stop spreading the rumor ...
>
> that it did
>
Hotmail did, indeed, try to migrate to NT. Two
things happened:
1. The engineers they hired to do the move said
that it could not be done, and that the systems
just could not stand up to the load.
2. The Unix admins threatened to quit on the spot
if they continued to threaten to move Hotmail to
NT. All of Microsoft's significant ISP services (Hotmail and WebTV, of note) run on Solaris. Hotmail uses some FreeBSD. Linux and FreeBSD, as well as NT, comprise some of the tools people use
on the backend for development and such, but the
infrastructure of both sites is primarily Solaris.
Note that all this information can be found easily by public means, so I'm divulging no information by saying this.
But will it have as good compression? :>
-Kysh
Aircraft navigational systems vary in frequencies
:>
and sensitivity. The real headache here could be
for a category IIIa ILS approach. The localizer will use something in the 108-114Mhz range, but
the glideslope is UHF.
Instruments like the ADF are sensitive to any
strong (And some weak) electronic signal, and will
swing to point to the strongest source of RF
emissions that pass its filters. Won't necessarily
be a cellphone, but you never know.
For me, a more convincing reason never to use
Cellular phones, or allow any passenger of mine
to do so would be:
As per FAR (15 CFR) 121.305:
(a) Except as provided in paragraph (b) of this section, no person may operate, nor may any operator or pilot in command of an aircraft
allow the operation of, any portable electronic device on any U.S.-registered civil
aircraft operating under this part.
(b) Paragraph (a) of this section does not apply to--
(1) Portable voice recorders;
(2) Hearing aids;
(3) Heart pacemakers;
(4) Electric shavers; or
(5) Any other portable electronic device that the part 119 certificate holder has determined will not cause interference with the navigation or communication system of the aircraft on which it is to be used.
And per 91.21:
(a) Except as provided in paragraph (b) of this section, no person mayoperate, nor may any operator or pilot in command of an aircraft allow
the operation of, any portable electronic device on any of the following U.S.- registered civil aircraft:
(1) Aircraft operated by a holder of an air carrier operating certificate or an operating certificate; or
(2) Any other aircraft while it is operated under IFR.
(b) Paragraph (a) of this section does not apply to--
(1) Portable voice recorders;
(2) Hearing aids;
(3) Heart pacemakers;
(4) Electric shavers; or
(5) Any other portable electronic device that the operator of the aircraft has determined will not cause interference with the
navigation or communication system of the aircraft on which it is to be used.
(c) In the case of an aircraft operated by a holder of an air carrier operating certificate or an operating certificate, the determination
required by paragraph (b)(5) of this section shall be made by that operator of the aircraft on which the particular device is to be used.
In the case of other aircraft, the determination may be made by the
pilot in command or other operator of the aircraft.
Or.. whatever.
I'm from the south, I have a southern accent. My
grammar is better than 90% of the people I speak
with or talk to online. English is my first
language.
About accents, regional accents are not a sign of culture. They're a sign of region.
---
> And the way some people in the US mangle words
> such as internet (inner-net), roof (ruff) and,
> route (rout) and many other words.
-Incomplete sentence.
-Sentence begun with conjunction.
-Proper pronunciation of 'Router' (Such as Cisco)
is 'Rowter' (Monosyllabic). I almost laughed my tail off the other day when I heard a canadian pronounce it 'rooter'. A 'Rooter' is something used to pull up weeds. See 'roto-rooter'.
-Canadians talking about stupid accents are being
pure hypocrites. All accents are stupid, if one
is prejudiced against people from the region of
origination.
-Kysh
* 'Class A' is obsolete terminology. /24, netblocks are not often SWIP'd, .ca, but retains SWIPs of their netblocks? You're f*@d.
* Portable netblocks could be pretty much anywhere
* Below a
even though it's possible to piece out smaller
bits of that netblock to pretty much any locale
* Dynamically checking the assignments of
netblocks from a whois against arin (whois -h whois.arin.net) is possible, but painful. Not to mention that you'd have to find an easy way to interpret the data you got back. And what happens if you have a major US backbone that services
-Kysh