On Ship Design Longevity

[Crazy Eddie]

That's a completely bogus argument. Simply use a thousand lenses.

It would take ALOT more than a thousand, unless you want to pull this trick at ranges of a few hundred meters or less. At distances of around a few kilometers, the object you're trying to analyze has a very small cross section, so scanning for an object that size requires enough lenses to paint that cross section on the area of a sphere; if that cross section is something like a few tenths of a degree, you're looking at tens of millions of lenses already.

Or, more probably, lenseless optics.

Which still requires you knowing where to focus those optics to gain the information you need.

What couldn't a passive system give?

Accuracy.

Not imaging ones, though.

Right. The image-seeking versions are too unreliable.

A trend that can be reversed with the use of better image interpreting software...

Sure it could, but why would you want to? Especially when semi-active measures will invariably have better performance even against improved image-recognition systems?

Why would, say, a radar be better at pinpointing a phaser bank?

Because an active radar beam can paint a target on a specific section of the enemy ship and keep that target fixed no matter where the target moves. This neccesarily means that you have to manually choose where to shine that target designator... but then, this is EXACTLY what happened when Khan fired on the Enterprise the first time, isn't it? The phaser lock wasn't just to gaurantee a hit on the Enterprise, it was to guarantee a kill shot even as Reliant's phasers pushed the ship aside and caused it to list several degrees to port.

You paint a target on your enemy exactly where you want the shot to go; you can't miss.

Just telling your camera-based system to stay locked to five and a half centimeters to the left of that red arrow pattern on the hull should do the same.

Sure, just not as accurately or as reliable as a similar beam-riding system.

If this isn't an option, you can MANUALLY aim the weapons to hit a particular target, and while this is entirely possible (sharpshooters have been doing it for 3000 years) it can't be done by computer.

That's just plain idiotic. Why would a human be better at it than a computer?

Because the computer only takes the guesswork out of an otherwise high-precision task. It cannot function in an environment where the task itself involves deciphering huge amounts of guesswork to begin with.

 

[Timo]

so scanning for an object that size requires enough lenses to paint that cross section on the area of a sphere

With a thousand lenses, only minimal movement on each would be needed to scan a 4pi field, so each spot could be in focus a few times per second. Devoting a bit more resources towards a region of interest when needed shouldn't massively reduce coverage, as there aren't likely to be that many interesting things around at any given time... But most of the time, a few nutating lenses should be able to stare everywhere at once. Certainly sufficiently to catch the emergence of a torpedo from Chang's mostly-cloaked BoP within much less than a second.

...And no active technique would do any better. They, too, would require receptors staring everywhere in order to make comparable use of the return signals. Those need focus, too - either "real", line optics focus or then "virtual", say, phased array timing -based.

Accuracy.

What does that mean? Resolution? Why would an active technique have better resolution than a passive one? Wavelength is wavelength, and that's where you get resolution.

Sure, just not as accurately or as reliable as a similar beam-riding system.

Sorry, you have to explain that again. What gives the active "there-and-back" beam an advantage over the passive "-back" beam here?

Surely a passive system would be inherently more accurate and reliable, because it doesn't have to worry about half the inaccuracy and unreliability of the twice as complex active system. Why bother with "painting" a spot and then watching that paint, when you can simply watch preexisting paint? The painting will give you nothing except extra intensity of signal, which you usually won't need and which gives no side benefits. And which makes you vulnerable by revealing your intentions - and, in many a case, your location or your very existence.

Because the computer only takes the guesswork out of an otherwise high-precision task. It cannot function in an environment where the task itself involves deciphering huge amounts of guesswork to begin with.

Utter nonsense. It's extremely basic: the target moves to left, you track left.

There'd only be "guesswork" involved if the target came with, say, live chameleon paint that moved right when the target moved left. But that'd confuse an active beam as well, across the wavelength ranges that mattered for finding the phaser bank, since that would be the purpose of the chameleon paint, and thus its effective wavelength range. And you can always watch the edges of the target for verification of movement even if the surface attempts to confuse you. Space is an incredibly friendly environment in that respect...

A good system would of course combine wavelength ranges and EM-independent methods, and every now and then (but reluctantly) throw in some active stuff. But the supposed superiority of active systems is still a mystery to me. The physics of it, I mean, not the historical ballast.

Timo Saloniemi

 

[Crazy Eddie]

so scanning for an object that size requires enough lenses to paint that cross section on the area of a sphere

With a thousand lenses, only minimal movement on each would be needed to scan a 4pi field

That depends on the radius of the sphere and the aperture of the lenses. At five kilometers, that sphere has an area of 62,000km^2; each of your thousand lenses is looking at a field almost 8 kilometers on a side.

A Klingon bird of prey is NOT eight kilometers in diameter. Therefore, if you want to identify it the instant it fires, you have to be able to instantly focus one of those lenses on a field 100 meters in a side.

...And no active technique would do any better. They, too, would require receptors staring everywhere in order to make comparable use of the return signals.

No, the thing about active scans is that you can send the signals in all directions and then listen for the return to get specific direction. Then you can focus more precise sensors to identify whatever that return is. Passive sensors work more or less the same way, just much less reliably.

Accuracy.

What does that mean? Resolution?

No, accuracy. Resolution is part of it, but in the end "accuracy" is about how well the information you get from your sensor scan actually represents what's happening on the enemy ship. If you peg his velocity at 220m/s instead of the 250m/s he's actually moving, your phaser strike is probably going to miss.

Sorry, you have to explain that again. What gives the active "there-and-back" beam an advantage over the passive "-back" beam here?

As an extreme simplification: if you know exactly the parameters of the beam you sent there, then you know exactly what it means when you record changes on what comes back.

Because the computer only takes the guesswork out of an otherwise high-precision task. It cannot function in an environment where the task itself involves deciphering huge amounts of guesswork to begin with.

Utter nonsense. It's extremely basic: the target moves to left, you track left.

And how do you know whether the target is moving left or YAWING left? As one of many examples: a passive system has few if any means to identify aspect changes to the target (if the target is turning or not) while an active system can actually map the features of that craft and report tiny doppler shifts as part of it begins to accelerate away from the source.

A good system would of course combine wavelength ranges and EM-independent methods, and every now and then (but reluctantly) throw in some active stuff. But the supposed superiority of active systems is still a mystery to me. The physics of it, I mean, not the historical ballast.

It's as simple as this: Active scans use more energy and more control of their emissions, which means they can gather more information more precisely than passive sensors. Thus active sensors ALWAYS have the advantage in the same situation; passive sensors only have the advantage of not giving away the scanner.

Really, if you have a choice between night vision and a searchlight, it is always preferable to use the searchlight; the only reason not to is because you don't want someone to see your lights.

 

[NIUPonyBoy]

Those models are the B-52's of ST, around forever it seems.

In reality, TNG was running on a budget and creating new ships that were worthy of detailed filming is pricey. So they pulled out ships from the movies. Makes sense as the few we saw 'fit' the plot alright.

What were the two 'originals' from TNG? Both being described as 23rd style ships. The Soyuz, we saw once and we silly ugly and an obvious knock around of a Miranda. And the only true new ship for TNG was the Constellation for the Stargazer. I actually thought it was an interesting ship if taken as a long range science ship or in war time a heavy scout. But did we see it again?

I am not an expert but from what I recall the Soyuz was a very short lived design in the ST'verse. The Bozeman was only 3 weeks old or something at the time of her 'loss." And you never heard much about that design. Now the Constellation was it ever seen again in fleet shots in DS9? I don't know, I would have liked to have thought of it lasting a little while too.

How long did the Constitution refit remain in service before the uber-long lived Excelesior class started taking over?

At any rate, by Endgame of VOY and the Dminion Wars of DS9 the Fed fleet had expanded quiet a bit.

 

[Manticore]

Those models are the B-52's of ST, around forever it seems.

In reality, TNG was running on a budget and creating new ships that were worthy of detailed filming is pricey. So they pulled out ships from the movies. Makes sense as the few we saw 'fit' the plot alright.

What were the two 'originals' from TNG? Both being described as 23rd style ships. The Soyuz, we saw once and we silly ugly and an obvious knock around of a Miranda. And the only true new ship for TNG was the Constellation for the Stargazer. I actually thought it was an interesting ship if taken as a long range science ship or in war time a heavy scout. But did we see it again?

I am not an expert but from what I recall the Soyuz was a very short lived design in the ST'verse. The Bozeman was only 3 weeks old or something at the time of her 'loss." And you never heard much about that design. Now the Constellation was it ever seen again in fleet shots in DS9? I don't know, I would have liked to have thought of it lasting a little while too.

How long did the Constitution refit remain in service before the uber-long lived Excelesior class started taking over?

At any rate, by Endgame of VOY and the Dminion Wars of DS9 the Fed fleet had expanded quiet a bit.

Don't forget the Ambassador, which was much more of an original design than the Bozeman (a kitbash of the Miranda), and arguably the Stargazer. Not to mention the Nebula, which wasn't just a Kitbash (at least, the semi-final version seen in The Wounded).

But yeah, it wasn't until Deep Space Nine and (especially) First Contact that the fleet started getting the diversity that we're used to.