Jim Henderson wrote:

> On Tue, 10 Nov 2009 10:17:16 +0000, Invisible wrote:
> 
>>>> I don't know, man... Backing up spinning disk to... spinning disk? Is
>>>> that such a sensible idea?
>>> 
>>> Why not? It's a backup. It's not like you can read a tape without
>>> spinning it. What are you going to back it up to, FLASH RAM?
>> 
>> Tape operates at much lower speeds. And since the only people who use
>> tape are people who want seriously reliable backup storage, it tends to
>> be very well engineered. (And stupidly expensive...)
> 
> Never used DAT drives for backup, have you? ;-)  Horrible quality of
> storage media, and terrible shelf life IME.

DAT saved my behind quite a few times. Never used a tape for longer than a
month though.
-- 
Stefan Viljoen

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Stefan Viljoen schrieb:
> 
> I'm seriously doubtful about the USAF planning regarding these aircraft. The
> F-22 specifically, it is so HORRIBLY expensive, and they have bought much
> less than the Air Force generals wanted. If they get into a fight with,
> say, China, which has got thousands of Mig-21s and comparable aircraft, I
> think they'll get whipped.

Even given that the MiG-21 pilots would "see" the F-22 at all before 
being hit by some long-range AA missile, that would be a problem only if 
the U.S. of A. had nothing else to bring into the air besides their F-22s.

> The simple reason being the F-22 is so expensive that the budget won't allow
> for enough AIM-120's or whatever to be bought. So you got, say, 70 F-22s
> sent to Korea or Taiwan for a fight with China (bear with my simplistic
> view of international politics.) They take along 200 of the available 600
> AIM-120 AMRAAM missiles. They use those to shoot down (perfectly, and at
> great range) 175 old, 1950's era MiGs.
> 
> But China has a thousand of those cheap aircraft. And the entire USAF has
> only 600 AMRAAMs, of which many still have to be shipped to Taiwan or S.
> Korea in order to get into the fight.
> 
> What happens next? The F-22s go "Winchester" - they have to engage in gun to
> gun duels, at low level (where the 60+ year old Chinese Mig-17, for
> example, is a KING of maneuverability.) The F-22 now has to go "low and
> slow" in the weeds, against a fighter that was DESIGNED for that, while
> itself is a beyond-visual-range 30 000 feet plus rather neurotic
> thoroughbred. 

You're having some misconceptions here:

(A) Besides being able to carry BVR AIM-120 AMRAAMs, the F-22 is 
designed to bear much cheaper AIM-9 Sidewinders into battle.

(B) Are you aware of what the F-22 can do in slow flight? Just take a 
look at this one - especially from 1:25 to 2:45:

http://www.youtube.com/watch?v=JTK3zeFRLO8&feature=related

(Thrust vectoring is the key to this, by the way.)

(C) As long as it's missiles against missiles, the MiG-21 will have a 
hard time getting a lock on the target. And when it comes to guns, the 
F-22 can always just outclimb or outrun the MiGs. Being good in a 
dogfight may be one thing, but being able to choose whether or not to 
enter into or leave one is another.

(D) You're forgetting about the countless F-15s, F-16s and F-18s (and/or 
the F-35s to come), that would fight side by side with the F-22.


> It's the Vietnam paradigm all over again, losing a tens of millions of
> dollars price F-4 Phantom in blowing up a bamboo bridge that is
> reconstructed that very night, with $3 Chinese bicycles once more carrying
> ammunition across it for the Viet Cong.

That's a totally different point. The U.S. of A. did have air 
superiority in Vietnam, and they will have it again and again and again, 
in whatever war you like.

The problem in Vietnam was that air superiority is only half the job 
when it comes to wrestling down an opponent in his own home country. But 
that doesn't make the F-22 inferior against MiG-21s.

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clipka wrote:

> Stefan Viljoen schrieb:
>> 
>> I'm seriously doubtful about the USAF planning regarding these aircraft.
>> The F-22 specifically, it is so HORRIBLY expensive, and they have bought
>> much less than the Air Force generals wanted. If they get into a fight
>> with, say, China, which has got thousands of Mig-21s and comparable
>> aircraft, I think they'll get whipped.
> 
> Even given that the MiG-21 pilots would "see" the F-22 at all before
> being hit by some long-range AA missile, that would be a problem only if
> the U.S. of A. had nothing else to bring into the air besides their F-22s.

Isn't this the way it is going? According to what I read on strategypage.com
recently, F-16s, F-15s and F-18 are wearing out and are not being replaced.
Additionally, much funding is being "saved" by decommissioning many
(hundreds, apparently) of these aircraft early as well, in order to spend
money maintaining the F-22 and F-35?
 
>> What happens next? The F-22s go "Winchester" - they have to engage in gun
>> to gun duels, at low level (where the 60+ year old Chinese Mig-17, for
>> example, is a KING of maneuverability.) The F-22 now has to go "low and
>> slow" in the weeds, against a fighter that was DESIGNED for that, while
>> itself is a beyond-visual-range 30 000 feet plus rather neurotic
>> thoroughbred.
> 
> You're having some misconceptions here:

Ok.
 
> (A) Besides being able to carry BVR AIM-120 AMRAAMs, the F-22 is
> designed to bear much cheaper AIM-9 Sidewinders into battle.

Of which there'll be how many? As far as I know the AIM-9X is not in
production anymore, and funding is being cut for buying it - again to be
able to afford "enough" AIM-120's and to feed the budgetary monster that
the F-22 has become.
 
> (B) Are you aware of what the F-22 can do in slow flight? Just take a
> look at this one - especially from 1:25 to 2:45:
> 
> http://www.youtube.com/watch?v=JTK3zeFRLO8&feature=related
> 
> (Thrust vectoring is the key to this, by the way.)

That's damn impressive! No, I didn't know that. That could come in very
useful in a low and slow situation. Though I wonder what the price is in
fuel consumption? High-alpha maneuvers like that probably need a lot of
thrust to be applied to keep from stalling?
 
> (C) As long as it's missiles against missiles, the MiG-21 will have a
> hard time getting a lock on the target. And when it comes to guns, the
> F-22 can always just outclimb or outrun the MiGs. Being good in a
> dogfight may be one thing, but being able to choose whether or not to
> enter into or leave one is another.

True, but that is a mark against the F-22 in my book. I was thinking when I
said that of the situation where US ground forces are under attack from the
air, and need to be protected against MiG strikes. So, the USAF sends the
F-22. It -has- to go low and slow to get at the MiGs, assuming it is out of
missiles. Sure, it can outclimb and outrun the MIGs, but it has no choice
now - it has to tangle with them on their terms, low and slow, to protect
US ground forces. Wouldn't that obviate its enormous speed and rate of
climb? (Though the slow maneuver you pointed me to above would obviously
help I readily agree.)

Also, that is if they have decommissioned all those F-16s and F-15s by that
time, of course - which seems to be the way they are going.
 
> (D) You're forgetting about the countless F-15s, F-16s and F-18s (and/or
> the F-35s to come), that would fight side by side with the F-22.

See above - it seems to me (I'm possibly wrong) that they are getting rid of
all those thousands of excellent aircraft in order to have F-22s and F-35s
as the largest percentage of available fighters. They can't do it
otherwise, the F-22 is simply too expensive to have it AND other fighters,
and still have enough $$$ for missiles, fuel, crews, training, etc.
 
>> It's the Vietnam paradigm all over again, losing a tens of millions of
>> dollars price F-4 Phantom in blowing up a bamboo bridge that is
>> reconstructed that very night, with $3 Chinese bicycles once more
>> carrying ammunition across it for the Viet Cong.
 
> That's a totally different point. The U.S. of A. did have air
> superiority in Vietnam, and they will have it again and again and again,
> in whatever war you like.
 
Ok. I meant it in the sense that, for the same effect, the United States
spends a billion on 10 aircraft of superlative quality, while China speds a
billion on a thousand aircraft of mediocre quality. But then those 10
aircraft only have 10 missiles each, because they themselves and their
missiles are so unbelievably expensive.

> The problem in Vietnam was that air superiority is only half the job
> when it comes to wrestling down an opponent in his own home country. But
> that doesn't make the F-22 inferior against MiG-21s.

I wouldn't consider it inferior - I fully agree that at BVR ranges (as long
as the missile supply lasts) it will probably knock anything flying out of
the sky, or just fuse enemy flight control computers with its radar. Where
I think it -might- have trouble though is when it is forced to move out of
its "comfort zone" - instead of high-altitude BVR, it is forced to go low
and slow, and use guns, against older aircraft that were specifically
designed to do that (while of course, being useless in the F-22's "comfort
zone").
-- 
Stefan Viljoen

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>> I'm glad it's not just me who constantly mis-spells "star". :-D
> 
> It's my keyboard! The **&%$ keyboard at wrk has its keys all placed one to
> the left of my home keyboard.
> 
> Oh gods, I just misspelled "work" too!

Put the shovel down. ;-)

>> Think about it: how long ago did we land
>> on the moon? And how long after that did we land on Mars? Oh, wait...
> 
> ... we haven't. Yup, three years out, three years back, or something like
> that?
> 
> And that's just in our solar system, never mind -real- interstellar stuff.

That's just THE NEAREST PLANET in the same star system. Never mind the 
more remote ones...

>> In fact, half the stars in the night sky probably DON'T EVEN EXIST ANY
>> MORE. It's just that it's taken that long for the light to reach us.
> 
> Now that's a depressing thought. Spending millions of years getting there,
> only to find that the star you were going to went nova or just collapsed in
> on itself a few hundred thousands years back.
>  
> Serious case for some kind of hyperspace or space-warping technology.

And of course, almost none of the stars are where they appear to be. 
They'll all have moved by now. I'm not sure how easy it is to figure out 
where they moved to.

And - sometimes I don't think people get this - you reach Alpha Proxima 
and radio back to Earth to say "hey, we got here, what next Houstan?"

IT WILL TAKE CENTURIES FOR THE MESSAGE TO REACH EARTH! >_<

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>> Compared to sitting still watching the game on TV, it involves *a lot* 
>> of muscle. ;-) And I can't really imagine that baseball requires less 
>> muscle power than football...
> 
> I think you haven't watched a lot of football.

I make a point of not watching it, yes.

> I suspect football players run more 
> in 10 minutes than a whole ball team runs in an entire game.

Wait - are we talking about American Football here?

>> I rephrase: I can run very, very fast indeed. I can't do this for more 
>> than a few seconds, however.
> 
> That's just practice. Really. When I first started doing stairmaster 
> exercise, I couldn't go for more than 5 minutes or so. Within maybe 3 
> weeks of trying three times a day, a full half hour at a higher 
> difficulty setting isn't even difficult.

Heh. Last night, I set a new personal best for fastest dancing. ;-) Damn 
that was crazy!

There is apparently something wrong with my brain. When I come home from 
a dance class absolutely dripping with sweat and gasping for breath, I 
find myself thinking "yeah, that was a really great evening". It's like 
I *enjoy* hurting myself. o_O

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>> In fairness, when was the last time you tried copying a file that 
>> somebody else was still using? Not so easy, is it?
> 
> Uh, yeah, it is, actually. Want my scripts to do it?

Heh. I too have written scripts to do backup. It seems like all you have 
to do is copy a bunch of files, but it's never quite that simple in 
reality. You have to deal with files that are locked, files getting 
moved around or deleted while you're trying to copy them, file security, 
alternate data streams, not upsetting programs working on those files 
just because you want to back them up, and so on. If you want to be able 
to do stuff like back up or restore an individual Exchange mailbox, good 
luck doing that with scripting. If you want to back up over a network, 
now you have connection issues, authentication issues, people turning 
the target PC off while you're accessing it...

...this stuff is way, way harder to do right than it sounds.

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> And - sometimes I don't think people get this - you reach Alpha Proxima 
> and radio back to Earth to say "hey, we got here, what next Houstan?"
>
> IT WILL TAKE CENTURIES FOR THE MESSAGE TO REACH EARTH! >_<

I wonder how much power you need to transmit with to be heard that far away?

I mean isn't the transmitter on Voyager or whatever about to go out of 
range, and that's only just left our own solar system!

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> I wonder how much power you need to transmit with to be heard that far 
> away?
> 
> I mean isn't the transmitter on Voyager or whatever about to go out of 
> range, and that's only just left our own solar system!

I think if you could make the signal directional enough, you might not 
need that much power.

Isn't that one of the unusual properties of lasers? They can travel 
great distances without the beam spreading very much?

On the other hand, I wonder how much noise the signal has to be detected 
over?

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>> For the average home user, if your house burns down, you're not going 
>> to give a **** about the holiday photos and the copy of Nero you just 
>> lost - YOU HAVE NOWHERE TO LIVE!! 
> 
> Not true. Well, Nero, maybe, but holiday photos and pictures of people 
> who are now dead and such are irreplacable. You can always get somewhere 
> new to live, or fix the house.

I don't know about you, but if my house burnt down, this would be a 
catastrophy. I would be homeless, and financially destitute. The bank 
isn't going to let you stop paying the morgage just because your house 
burned to the ground. And with no house to sell, it is impossible to buy 
a replacement. I'd basically be homeless for the rest of my life. I 
wouldn't be able to *afford* a computer! Why would I care about some 
holiday photos when I'm going to be spending the rest of my life on the 
streets?

(And then there's the "minor detail" that your backup copies will be in 
your house, and thus destroyed in the process...)

>> This is a very, very dumb way to do backup. A file-level copy will be 
>> drastically faster. (It doesn't involve mirroring all the useless 
>> empty sectors.) 
> 
> Depends how your RAID works. Windows doesn't mirror empty sectors 
> because the RAID understands the file system. Linux and hardware mirrors 
> empty sectors because you can put any file system on top of the RAID.

Well, as I say, it depends on what you're trying to do.

If you're trying to avoid downtime due to hardware faults, RAID is the 
right tool. If you just want to avoid losing a few specific precious 
files, a file-level copy seems more appropriate.

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scott wrote:

>> And - sometimes I don't think people get this - you reach Alpha Proxima
>> and radio back to Earth to say "hey, we got here, what next Houstan?"
>>
>> IT WILL TAKE CENTURIES FOR THE MESSAGE TO REACH EARTH! >_<
> 
> I wonder how much power you need to transmit with to be heard that far
> away?
> 
> I mean isn't the transmitter on Voyager or whatever about to go out of
> range, and that's only just left our own solar system!

I think Voyager uses something like 10 watts or so?
-- 
Stefan Viljoen

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