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ChezDaJez -> RE: What do you think of Yamato? (4/7/2005 1:59:07 PM)
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ORIGINAL: ChezDaJez
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Mostly not so. Turn radius and the relatively more stable platform prove to be ephemeral advantages to gunnery performance in actual use, as the first characteristic would tend to cancel the second out to a degree.
Absolutely not true. The ability to maneuver is absolutely critical to a warship and becomes even more critical at long range. The effects of maneuver on fire control solutions hampers the targeter far more than the target regardless of radar or optical direction. It is extremely difficult to predict where a ship will be that is zig-zagging. A steady course is required for such a prediction. No fire control computer can do it even today, they can only predict where a ship should be at a steady course and speed. It is also far easier for a ship to adjust for own ship movement than the enemy's.
Yamato could also turn a full circle with a diameter of only 640yds at top speed. Iowa needed at least 840 yds to do so. Yamato also had an auxilliary rudders on either side of the keel some distance forward of the main rudders. This allowed her to perform a sideslip maneuver that the Iowa could not duplicate. As gun directors attempt to predict where an enemy ship will be at a certain point in time, the ability to maneuver rapidly away from that point can mean the difference between a hit or a miss.
You're only bothering to look at that from one point of view, and in any event you manage to completely confuse my original remark.
You also ignore the theory of spreads which tends to defeat salvo chasing and such. Not completely, of course, but it's difficult to race out from under that sort of wide-spread rain of death.
Anyway, in this regard all I said was that Yamato would lose some of her superior "stability" when making such tight turns, and this would lead, to whatever degree, to more degradation of her fire plots and/or a delay in obtaining reliable ones. That point you completely ignore.
I do believe it is you that is fixated on one point of view and what point did I miss? That you said ships can't turn and shoot without messing up a fire control solution? Hardly. I chose to disagree with your "point". Zig-zagging induces little error to a fire control solution. The biggest problem is keeping the guns trained, not the FCS. I used an example of her smaller turning diameter which you obviouyl took to mean she would be in a hard turn continuously. Silly you. As I said, a ship can rapidly adjust for its own movement and turns of up to 45 degrees induce little if any delay in shooting.
Of greater immediate benefit is the ability to not be where the enemy is predicting you to be by either salvo chasing or zig-zagging unpredictably (note key word- unpredictably). That requires manueverability and is critical to survival, especially in the face of a better FCS. Do the math. A 27kt ship moves 900 yds in 1 minute. That's the approximate flight time of shells at long range. See the purpose is not to stand toe to toe and slug it out. The purpose is to deliver more punishment to your enemy than what you receive. That means shooting AND manuevering, something that warships of all navies did. Steaming in a straight, predictable line while under fire is tantamount to buying a one-way ticket to the bottom. What is it about that you don't understand?
Salvo spreads? Oh, yeah, the old Sherwin Williams shooting tactic. Paint the ocean with shells! One's bound to hit sooner or later! Salvo spreads were a WWI tactic that were used to compensate for inadequate fire control solutions and were generally unnecessary for WWII naval gunnery. The RN used it early on some of their ships due to the primary optics being located on the main guns. Once they corrected that deficiency, they didn't use it again.
Now if you are referring to salvo bracketing where guns were directed to fire at slightly different ranges, typically 200yd steps, that's a different story. This is where a 3-turreted ship would direct one turret to fire over, under and on the indicated range. This was done to create a "box" around the target after a first hit. The MK 8 system wasn't capable of doing this as it provided the same information to all turrets.
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All warships are on the move when firing. If they arent, they are literally sitting ducks. Just because an optical system wasn't "state of the art" has little bearing on its effectiveness in battle.
NOTE: Well, you made a logical error there, which I'll just clean up so there's no mistake on anyone else's part: Chez didn't mean to say that Yamato had inferior optics, just the opposite was in fact the case. And of course, the quality of optics has a lot to do with performance in battle, as it must.
Now who's missing the point. There's no logical error there. Just because a system is no longer "state of the art" doesn't mean its ineffective. Is that better? Semantics pure and simple, teacher. Their optical systems were state of the art and superior to the Americans. That fire control radar is more accurate and can provide a faster solution doesn't negate the effectiveness of another system nor does it make it less accurate than it was before.
The MK 8's, while generally more accurate, was compromised in many subtle ways. The Mk 8 mod 2 system had a published range accuracy of +/-15 yards and bearing accuracy of +/-2 mils. Quite remarkable except for one little detail. That's the theoretical accuracy of the pulse itself. It doesn't take into account the inherent inaccuracy of the radar PPI display which can be measured in hundreds of yards depending upon target aspect and speed, especially for the crude CRT displays used in WWII. Even today's naval radar displays can have range inaccuracies of 2-4% and bearing inaccuracies of 2-3 degrees, especially when using in sector scan. (That comes from first hand knowledge operating radar systems in the Navy). Range input was provided by the MK 8 operator who had to manually select the target for input. This can result in another induced range and bearing inaccuracy depending upon what part of the radar return he marks. I don't think its unreasonable to assume that the system had a built-in range inaccuracy of 500-1000yds depending on target range, especially if the target is manuevering.
Another important point is target identification. Today, we have decent IFF systems. In WWII, IFF was in its infancy and seldom provided reliable indentification. Blue on blue engagments were common place in WWII and still happen today. They happen because an operator has identified a target through radar detection only without using other means and believes it to be hostile. In WWII, avoidance of blue on blue meant visual identification, something very suited to optics, especially Japanese night optics.
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Getting back to what you seem to have meant to write: the ultimate quality of a ship's fire-control system has a lot to do with a battle's outcome, I dare say it has nearly everything to do with it. This quality also bears directly on the matter of relative fire-control effectiveness between one ship and another. It isn't as if we're talking about keeping score on a some static range here during exercises. We speak rather to a hypothetical real-time combat where an extra hit or two probably will make all the difference, and moreover, where that extra hit or two will almost assuredly come at the expense of Yamato.
"static range here during exercises", hmmm..... "hypothetical real-time combat" , hmmm. One's a real shooting exercise, the other is a hypothetical combat.... hmmm.... Let's see...
Hypotethetical: "theorectical, imaginary, supposed"
Exercise: "training to acquire skill in the management of arms and in military evolutions"
I'll take exercise over hypothetical every time.
That radar controlled FCS systems are generally more accurate than optical systems is undisputed, never said they weren't. But in conditions that suited optical range finding, the differences in range determination were negligible. The best data I could find for Japanese optical systems indicated an accuracy of +/- 500yds. This compares fairly well with induced range errors on the MK 8. As far as speed of solution goes, no expert here but I don't think it matters much as long as the FCS could provide accurate targeting data within one gun duty cycle.
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Yamato and Musashi had the finest optical fire control system in the world, far superior to the optical system employed by the Iowa.
I don't know if that's true, first of all. The Germans had the same optics, if not better still. The Japanese took their optical designs from German plans, and as I've already agreed that Japanese optics were far superior to American optics, what's your point in mentioning this?
You don't know if that's true yet you dispute it anyhow. The Japanese did get their intial optics from Germany beginning in 1923. However, they then also hired German technicians and began there own optical research and bythe time war started, had greatly improved them over those of Germany. The actual design of the range finder came from the British-built Kongo. Heres a quote from "Nikon and the Sponsorship of Japan’s Optical Industry by the Imperial Japanese Navy, 1917–1945 JEFF ALEXANDER University of British Columbia"
Each of these 70,000-ton vessels was designed to feature three 18.1-inch turrets, and represented the firm determination of the IJN to outrange all other navies. Superlative artillery, however, also necessitated superlative fire-control optics, and Nippon Kôgaku was therefore tasked with the production of eight 15-metre rangefinders capable of providing images of targets at distances of over 35 kilometres. One of the finished devices was affixed to each of the three main turrets aboard both the Yamato and the Musashi battleships, with a fourth installed on their forward fire-control towers. The creation of these massive instruments involved such a high degree of engineering precision that the standard of accuracy in their prism construction was 60 times greater than that which had been applied to conventional projects. Nippon Kôgaku had not only set new design standards when it had furnished the IJN’s flagship Yamato with the optics necessary to fight, it had also raised the technological capability of the Japanese optical industry as a whole.
Nippon Kôgaku became Nikon after the war.
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Iowa's main advantage was with her radar directed fire control. Without it, she is at a slight disadvantage.
I'm not even convinced that's true insofar as Iowa could always get off more rounds faster than Yamato, and while her optics were inferior it is not all that clear that they were that inferior. Perhaps they were, but I don't know; neither would I know how to demonstrate this one way or the other.
Now who is misinterpreting who? The point here, clearly stated, is that Iowa is at a slight disadvantage in determining a FCS solution if she has to rely solely on optics. She will be slower in providing solutions and accuracy than Yamato, a ship well versed in using optics. Rate of fire hardly matters in this determination unless you are using the Sherwin Williams tactic again.
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Yamato certainly had the ability to provide quick and accurate fire control solutions.
Relative to what?
She was slower in this area than Iowa. That's the only pertinent point in this debate.
Granted she's slower, been saying that. But is that difference going to adversely impact supplying data to the guns. I don't think so. Slower is a relative term. I doubt anyone knows for sure what the actual data relay times were for both ships but they certainly would be measured in seconds, not minutes. The relayed data should arrive in plenty of time to adjust the guns before the next salvo was ready to shoot. Both ships could sustain a rate of fire of 2 rounds per minute per gun.
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Granted, not as quick as Iowa, but still sufficiently quick that the guns were not waiting on input before firing the next salvo.
We need to slow down here.
As a matter of course there is bound to be a delay enforced on Yamato's solutions relative to Iowa immediately after the first salvos are loosed. Yamato must observe her fall of shot, then make the calculations, which are slower than Iowa's. Iowa then gets off her second salvo while Yamato's still figuring hers. Soon enough Iowa is on her fifth salvo while Yamato's still computing her fourth, and like that. Yamato would never catch up, always fall further behind, eventually fall fatally behind.
Here we go again. Need to slow down here? Why? Something you don't understand?
Neither Yamato, nor any other BB, needed to observe their fall of shot before firing the next salvo. That was soooo WWI. Adjustments could be made to the third salvo if necessary. That some navies chose to do so doesn't apply here. In every surface battle that Japanese surface forces participated in, they did not wait to observe the fall of shot before the next salvo went downrange. You imply that Iowa didn't need to observe her shot. By your argument, she should if she wants to be more accurate. Afterall, her FCS was supposed to be able to detect the fall of shot, wasn't it? And don't forget the Yamato had an adequate surface search radar that could also back up the range determined by the optical sights. It just couldn't offer any predictions.
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Yamato's FC did have a greater chance of induced error due to its labor intensiveness but the solution itself took little time to achieve. Also, Yamato's FC system allowed for the input of radar or optical data and provided more information than did the Iowa's Mk 8 mod 2 system such as bearing rate which can be used to calculate target speed or range independent of an optical or radar range finder.
I've no idea what you're talking about there. Are you saying Yamato had some potential for radar-fed critical plotting data and then could actually use this over and above what Iowa employed? If so, you're dead wrong. And the Mark 8 Mod 2 was state of the art. It was somewhat different than the approach used by the Japanese but its real drawback was the indifferent optics.
I quoted this from the Navweps website:
"The Shagekiban receives range information from the rangefinders and target course and speed information from the Sokutekiban. After receiving this information, the Shagekiban now has enough information to generate gun orders. These are then transmitted back to the director where calculations are made for roll in the line of sight, cross roll for elevation and train, and parallax. Once that is done, the director transmits the orders to the guns via a follow the pointer. "
The Shagekiban was capable of receiving manual input from any source including search radar. So if the optical directors were blinded, radar range data could be used to generate a workable solution. Not as fast as optical data because the Japanese search radar had to be trained by hand. It did not rotate automatically.
And where did you get I said "over and above Iowa?" The only difference was that the Japanese system provided bearing rate information that the Iowa did not use. Bearing rate info is useful for computing reasonably accurate course, range or speed information when 2 of the 3 variables are known. We used this info all the time on the P-3s and carried a HP-67 programmable calculator to compute it.
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Yamato was not a more stable gun platform in spite of her seakeeping characteristics vis-a-vis Iowa. In fact, the worse the seas became the more the gyro-stabilized Iowa system would pull ahead of Yamato.
You accuse me of misinterpreting your words yet you are the king at it. Let me try this one more time. A rolling ship has a harder time keeping her guns on target. That is the gun barrels at the correct elevation. The FCS can be providing the most outstanding information but it is absolutely useless if the guns can't stay on train. A wallowing ship, with poor seakeeping abilities (Re: IOWA), is going to find it much harder to stay on target in a heavy sea than a more stable ship like the Yamato. Yamato's stability came from her much greater beam (121ft vs 108ft). It has nothing, repeat nothing, to do with the fire control solution.
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The physical positioning of finders is not much of an issue, except for height, where more, other things being equal, is better, but then other things are not always equal. In any event, one direct hit on any finder means kaput, and it's impossible to predict where those hits might actually strike home. Should a finder go south, however, then Yamato would be in something of a fix, whereas Iowa would still be capable to deliver reasonably accurate fire quickly due her more sophisticated radar. In turn, Yamato would then be reduced to local fire control. Not good.
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Height is the primary location requirement for optical and radar range finders as greater height allows for targeting at longer ranges. Range finders mounted on the guns themselves are practically useless at ranges over 15000 yards due to the inability of the rangefinder to interpolate the waterline of the target. As optical range finders most often used mast heights for range calculations, a clear line of sight to the waterline is necessary for accurate range solutions.
I don't think you've bothered to read (for meaning) what I've written. You're only repeating me here.
You again missed the point. You say physical positioning of the finders isn't important, except for height. Then you go into some indecipherable gibberish about more being better but things not being equal. What the hell are you talking about?. Are you referring to the number of directors? Yamato had 4 15-meter finders. You also fail to mention what would happen to Iowa's targeting ability if she sustained a similar hit to her primary FCS. Iowa would then also be reduced to local control and in a worse situation than Yamato.
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She'd have the advantage of her superior optics if weather and time of day so allowed. As it turns out Japanese doctrine and practice was to seek surface engagements at night. They were well aware (as was Admiral Spruance!) of their advantage in that respect over the Americans, so it's odds on that Yamato would have effectively sacrificed whatever advantage she enjoyed with respect to optics. Had Iowa's radar gone haywire under a full moon and a clear night sky then I'll grant you Yamato would have enjoyed an advantage with regard to spotting. But again, what are the odds of that happening?
So, let me see if I understand what you just said. You said that Japanese doctrine was to fight at night where they had the advantage but the night would also remove the advantage of their optics. What?! Aren't you forgetting the Japanese pratically invented night surface fighting? You say Yamato would only have the advantage on a bright night. You seem to forget that the Japanese night fighting abilities were quite good, regardless of weather. Remember, the first Battle of Savo Island... at night, in the rain, against a radar equipped force? And what advantage would Iowa have on a dark night without radar? What are the odds of Iowa losing her radar? I'ld say pretty damn good the moment she was hit or when her first salvo was fired. You sure can twist things, can't you?
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It doesn't matter how stable a ship's hull is. It only matters how 1) accurately and 2) fast a fire-control system can acquire its target. And on both of those points Iowa was a league ahead of Yamato, most especially in heavy seas. Her system was designed to afford her this advantage.
One more time, accurate fire control solutions aren't any good if the guns can't stay on target in a heavy sea. Yamato has the clear advantage here for stability.
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Gunfire is only accurate if the barrels can be kept to the correct elevation. Yamato, with her broader beam and reduced roll rate, would have an easier time than Iowa. Obviously a calm sea negates this advantage but ships didn't always get to pick the conditions under which they fought. Yamato also had a greatly reduced pitch rate over the Iowa.
I'm not sure to what degree Yamato would have gained (or rather lost less ground) to Iowa in calm seas as opposed to heavy seas. And again, you seem to disagree with this, as your message is that Yamato would lose some of her advantage in a calm sea state. I see it exactly opposite. To whatever degree that Yamato did pitch and roll and yaw in a heavy sea, she was incapable of keeping up with these erratic motions the same as Iowa could, this in reference to their respective fire-control technologies and the solutions these provided, and that's why Yamato would be better off in calm seas than violent seas. The worse the weather got the more Iowa's superior technology came into play, and thus the further ahead she drew.
Gees, Louise... Yamato gains an advantage in heavy seas that she doesn't have in a calm sea. Get the picture? Neither ship rolling? No advantage. And there you go again with this fire control solution garbage. Can Iowa's guns stay on target in a heavy sea? Answer: NO. Can she use that fire control solution if the guns can't stay on target? NO. And to whatever degree Yamato did pitch and roll and yaw in a heavy sea, Iowa would be much worse.
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One other point that is germane is that Yamato also had better torpedo protection than did Iowa, especially in the vicinity of #1 turret. This is important for those shells that land close aboard. Yamato was designed to withstand torpedo warheads up to 860lbs whereas Iowa design requirement was for only a 680lb warhead. Yamato's protection did have its faults, particularly where it joined with the main belt. Iowa torpedo blister also did not extend under the magazines whereas the Yamato's did. Its probably best that the Iowas were never struck by a torpedo(s). It is unlikely she could have withstood half the torpedo hits Yamato or Musashi took.
That would be a one-in-a-thousand chance. Perhaps more like one-in-ten-thousand or one-in-ten-million chance. It'd be like getting bopped on the head by one of Scholl's "satellites."
You obviously overlooked the point that Japanese shells sometimes penetrated through the bottom of a ship before exploding. Not likely to happen on the Iowa class, but certainly underwater hits are germane.
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But even as far afield as that point is I'll cede it to you if it's so important. Yes, Yamato was better protected. (And given her relatively crap fire-control system vis-a-vis Iowa's she'd certainly need to be!)
My, aren't you gracious? Obviously everything thing else in my earlier post was so important to you that you had a burning desire to nitpick every little point and nuance without providing any new information. You just don't miss any opportunity to display the superiority of your opinions, do you? Whatever.
Chez
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