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RevTKS

Yamato vs Iowa article...interesting tidbit

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Referring to Iowa's test firing under extreme maneuvers: “This was a much better performance than other contemporary systems,” he continues, “and gave U.S. battleships a major tactical advantage, in that they could both shoot and maneuver, whereas their opponents could only do one or the other.” 

This is a quote from this article http://nationalinterest.org/blog/the-buzz/heres-what-would-happen-if-the-2-most-powerful-battleships-25670?page=2

(it has several sections that repeat, or it could be a browser issue)

Anyway, that quote blew me away. I knew that generally WWII era tanks could move or shoot, not both. It had not occurred to me that a warship would not be able to conduct maneuvers while attempting to fire (or achieve a firing solution). Probably just me being a bit of a dolt, but I found that interesting. 

Also, the article doesn't give us much info on who would win between the two big girls. The author gives a slight advantage to Iowa, but states that all it would take is one or two 'lucky' shots to doom Iowa...and if those shots were early, well quick game over. 

 

 

Edited by RevTKS

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10 minutes ago, RevTKS said:

Referring to Iowa's test firing under extreme maneuvers: “This was a much better performance than other contemporary systems,” he continues, “and gave U.S. battleships a major tactical advantage, in that they could both shoot and maneuver, whereas their opponents could only do one or the other.” 

This is a quote from this article http://nationalinterest.org/blog/the-buzz/heres-what-would-happen-if-the-2-most-powerful-battleships-25670?page=2

(it has several sections that repeat, or it could be a browser issue)

Anyway, that quote blew me away. I knew that generally WWII era tanks could move or shoot, not both. It had not occurred to me that a warship would not be able to conduct maneuvers while attempting to fire (or achieve a firing solution). Probably just me being a bit of a dolt, but I found that interesting. 

Also, the article doesn't give us much info on who would win between the two big girls. The author gives a slight advantage to Iowa, but states that all it would take is one or two 'lucky' shots to doom Iowa...and if those shots were early, well quick game over. 

 

 

Yeah, interesting tidbit. Such is the power of a radar integrated combat control system. 

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It's also a load of excrement from a male bovine.

You don't just stop that much steel in the middle of the ocean and then aim and fire and then start up again.

Jesus. That's one of the most idiotic concepts I've ever heard.

You have rangefinders and such, and do maneuvering boards to figure out not only where your target is at relative to you, but what your relative position will be at the end of the shell's TOF assuming nobody maneuvers, and then you point the guns there. By the time Yamato came around, they had automatic analog stuff, electrical "computers" of sorts, that used cam wheels to automagically compute lead, based on input from the director. It doesn't matter if it's radar or just optical, the link between the turret and the director is still automatic.

There was no such thing as stop-and-fire in naval warfare.

ever.

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This Iowa vs. Yamato topic has been debated ad nauseum, and if I recall, that particular article was posted in the historical section of the forums. I don't take much stock in it since it mainly consists of gross simplifications and generalizations. National Interest is not exactly a paragon of journalism either.

 

Now, regarding fire control, maybe @Azumazi can provide more information, but I'm not aware of the Yamato having automatic gunlaying or remote power control (RPC) for the main batteries. As far as I know, the Yamato still used the follow-the-pointer system. The automatic gunlaying is what enables the Iowa to maneuver and fire; the radar rangekeeper is merely one input in the control loop.

Edited by DeliciousFart

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Yamato's main guns had RPC, but they were complicated to operate in that to use the backup FCS to direct it, they had to bring the guns back to neutral at 0 degrees and reset the FCS system to direct it again off the rear FCS for RPC. There is debate if the 15.5cms or the 12.7cm gun systems had them at all, but it should be noted the Yamato class did have the only FCS with a basic gyroscope for direct input of heading/bearing which helped simplify input into the system. Everything else still had to be manually put into the computer.

But yeah, main guns, yes, everything else, pretty much no at least ill 1945 if they at all added it to the Type 89s

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5 minutes ago, Azumazi said:

Yamato's main guns had RPC, but they were complicated to operate in that to use the backup FCS to direct it, they had to bring the guns back to neutral at 0 degrees and reset the FCS system to direct it again off the rear FCS for RPC. There is debate if the 15.5cms or the 12.7cm gun systems had them at all, but it should be noted the Yamato class did have the only FCS with a basic gyroscope for direct input of heading/bearing which helped simplify input into the system. Everything else still had to be manually put into the computer.

But yeah, main guns, yes, everything else, pretty much no at least ill 1945 if they at all added it to the Type 89s

How would you judge the effectiveness of Yamato's RPC compared to contemporary systems? The development and employment of RPC was undertaken by several navies but not all of which were considered successful; French RPC for instance was considered questionable when examined by the Germans and there's not much information about the reliability of Italian RPC.

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28 minutes ago, LT_Rusty_SWO said:

It's also a load of excrement from a male bovine.

You don't just stop that much steel in the middle of the ocean and then aim and fire and then start up again.

Jesus. That's one of the most idiotic concepts I've ever heard.

You have rangefinders and such, and do maneuvering boards to figure out not only where your target is at relative to you, but what your relative position will be at the end of the shell's TOF assuming nobody maneuvers, and then you point the guns there. By the time Yamato came around, they had automatic analog stuff, electrical "computers" of sorts, that used cam wheels to automagically compute lead, based on input from the director. It doesn't matter if it's radar or just optical, the link between the turret and the director is still automatic.

There was no such thing as stop-and-fire in naval warfare.

ever.

Given the phrase "under extreme maneuvers", I think the concept here is less "stop and shoot" which, as you said, would be stupid and has never been a thing in naval warfare, and more shooting while going in a straight line as opposed to firing while jamming the rudder to one side and/or trying to radically change speed. In situations of such extreme maneuvers there might be a lag time introduced where the rangefinder and electromechanical systems are having to make more significant changes to their calculations more quickly, therefor introducing larger error. If the information from one "tick" of the rangefinder's computation is significantly off from the target's actual relative position and course when it reaches the turret, then the shot won't be as accurate.

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2 minutes ago, DeliciousFart said:

How would you judge the effectiveness of Yamato's RPC compared to contemporary systems? The development and employment of RPC was undertaken by several navies but not all of which were considered successful; French RPC for instance was considered questionable when examined by the Germans and there's not much information about the reliability of Italian RPC.

They seemed to have felt it was effective, but that's hard to compare to US and British RPC when both ships were sunk and we only know that they had RPC based off the French systems.

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4 minutes ago, Landsraad said:

Given the phrase "under extreme maneuvers", I think the concept here is less "stop and shoot" which, as you said, would be stupid and has never been a thing in naval warfare, and more shooting while going in a straight line as opposed to firing while jamming the rudder to one side and/or trying to radically change speed. In situations of such extreme maneuvers there might be a lag time introduced where the rangefinder and electromechanical systems are having to make more significant changes to their calculations more quickly, therefor introducing larger error. If the information from one "tick" of the rangefinder's computation is significantly off from the target's actual relative position and course when it reaches the turret, then the shot won't be as accurate.

 

These systems didn't "tick." They're analog, not digital.

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I might be wrong but I think its to do with the turret traverse speed when at high maneuvers, those big monsters don't just turn to where you want them,

as seen in the game, go full radar on yammy and your turrets don't keep up

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For ships guns to be accurate they need to be on a relatively stable platform, slow speeds or rapidly altering course do not help create a stable platform nor do they create a consistent range for ships requiring manual input of target data. Anyone thats ever been on a ship can tell you that during hard turns, everything shakes.

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4 hours ago, LT_Rusty_SWO said:

It's also a load of excrement from a male bovine.

You don't just stop that much steel in the middle of the ocean and then aim and fire and then start up again.

Jesus. That's one of the most idiotic concepts I've ever heard.

You have rangefinders and such, and do maneuvering boards to figure out not only where your target is at relative to you, but what your relative position will be at the end of the shell's TOF assuming nobody maneuvers, and then you point the guns there. By the time Yamato came around, they had automatic analog stuff, electrical "computers" of sorts, that used cam wheels to automagically compute lead, based on input from the director. It doesn't matter if it's radar or just optical, the link between the turret and the director is still automatic.

There was no such thing as stop-and-fire in naval warfare.

ever.

Yeah...pretty sure they were trying to convey the idea that US BBs could conduct radical maneuvers and maintain an accurate firing solution whereas other BBs would have to maintain a constant course and speed, fire, maneuver, rinse and repeat. The US system of Mk1 Able mechanical computers  and the Mk 38 GFCS was just better than what many navies--esp the IJN--had at the time. IIRC NC conducted a test where shes was conducting high speed figure 8s and never lost target lock. Most ships of the day couldnt do that.

Not saying the other navies had trash...they just didnt have the Mk 1A

Edited by BBsquid
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To those curious, the reason they could not shoot and maneuver is that, at that time, Combat Fire Control Computers relied on Constant Bearings to get firing solutions. It doesn't matter exactly WHAT that bearing is, but it must remain constant. If you, or your target for that matter, change bearing, there was no way at that time for 90% of ships to account for this change in direction and thus, the computer cannot get a firing solution.

The reason the USN (it was not just the Iowa's that were capable of this, all ships from the New Mexico class, on, were capable of firing and maneuvering) and the Royal Navy, (and *only* these two Navies, for a key reason), from the Nelsons, on (although they retrofitted the QE's and R Classes (and the R Class CC's as well) but not the Hood, interestingly, could do so was that their steering gears were not direct control. By that I mean, these ships were all 'fly by wire' when it came to rudder course modifications. See there are these things in control science called "PID's"  Controllers which stands for Proportional Integral Derivative Controllers. In laymen terms... how best to describe this...

So okay, most people know how a standard, home oven works right? You set it to a temperature, say 350 Degrees Fahrenheit. To reach that temperature the heating elements turn on. Not turn on to 50% their heating capacity, not turn on to 75% heating capacity and throttle down as it approaches the set point, they just turn on, full blast, 100%. Once the thermometer inside the oven reads 350 degrees, they turn off, and the temperature wobbles (in control terms, "Perturbates" ) around that set point as the elements turn on and off. If you graphed the temperature, it would just look like a sine curve, just wobbling above and below the set point and in reality spending VERY little time *at* the desired set point. This is (sorta) fine in an oven, but on a ship, trying to shoot another ship, where a single degree off could result in an overshoot/undershoot of 100's of meters, these lack of accuracy in control of bearing causes HUGE problems when trying to fire while maneuvering.

A PID Controller (along with other types of controllers) work a bit more exactingly/accurately. Instead of turning on the elements 100% on till a set point is reached, it turns on say, 75%, until it reaches 300 degrees, then turns down to say 25%, and when it reaches 340 degrees, down to 15%, and incrementally down till it maintains at 350. In control theory, 'overshoot' is where you exceed that set point, and have to fall back into it (on the first 'wobble'). PID's seek to minimize that Overshoot as much as possible (to the point where it 'effectively' does not exist) and to reduce 'noise' in the system after that point. They are slower to react, for the obvious reasons, but FAR more accurate and *super* predictable (so that you can say, base a calculation not on where you are in that control curve, but where you will BE at x deltaTime in the future).

PID_varyingP.jpg

These are all graphs of a controlled process, the one that you would *want* is the Red line, as it slides into the set point (1) gently and gradually and, importantly, Predictably, with minimal (none) overshoot. That first 'bump' that the green and purple have is the overshoot, and the Blue line would be what we call a step change ('instantaneous' change, like flipping a switch on a circuit)

This matters in this context because the *first* PID's ever to be used were fitted to Battleships, specifically the New Mexico class to control the rate of turn on the ship's rudder. Initially, so that ships would slide into a turn smoothly without overshooting and having to steer 'back' to the desired bearing. But this had the EXTRA effect of making their own maneuvers HIGHLY consistent and most importantly, predictable. When the Ford Mk1 Computer came out, this data was fed into it as one of the control points that allowed USN Battleships (or any ship fitted with a PID controlled rudder (and later, many other parts of the ship were placed under PID/PI Control)) to maneuver while firing because their own changes in bearing could immediately be accounted for and predicted. The Royal Navy also adopted these and were also capable of firing and maneuvering (as shown during the Final Battle of the Bismarck/Final Battle of the Scharnhorst)

HOWEVER this *only* applied the ship itself, not it's target. So if a target being fired at was rapidly changing it's bearing, the Mk1, and subsequent WWII era computers COULD NOT in real time predict the new firing solution, and would require the target to stabilize. This wasn't a problem because, as stated, NO OTHER enemy nation was capable of firing while maneuvering, and thus, you were 'safe' waiting for them to stabilize.

 

Edited by _RC1138
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The hard end results of this advantage were plainly demonstrated by the combat between the 3DD's (and 3DE's) of Taffy 3 against the IJN  at the Battle of Samar.  " Last Stand of the Tin Can Sailors " has some very good descriptions of US naval gunnery  in action at the time and what it was capable of. Though IIRC the DE's only had local/manual control , the DD's were the ones with the firecontrol noted in this topic.

Combine that withthe  fine article http://www.combinedfleet.com/baddest.htm. Note: he is very careful in not goring anyone's Ox , it is a skill he has. 

And it is reasonable to assume that a battle between US and IJN warships of the time (i.e. if Halsey had sent Lee's BB's south instead of north) would have resulted in a total shredding of the IJN surface forces. (The Iowa's and the NC's/SoDak'saneuver and fire like those DD's at Samar , albeit being a little" bigger" LOL) Then there would have been the attached smaller ships as well  with the similar advantages (US DD's attached to the BBs, etal.), besides US air,, to remove any doubt

edit  monster eating my post

Edited by Strachwitz666
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6 hours ago, Strachwitz666 said:

And it is reasonable to assume that a battle between US and IJN warships of the time (i.e. if Halsey had sent Lee's BB's south instead of north) would have resulted in a total shredding of the IJN surface forces. (The Iowa's and the NC's/SoDak'saneuver and fire like those DD's at Samar , albeit being a little" bigger" LOL) Then there would have been the attached smaller ships as well  with the similar advantages (US DD's attached to the BBs, etal.), besides US air,, to remove any doubt

This and Jutland are probably the two biggest lost opportunities for surface glory in the history of naval warfare.

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By mid 1943-early-1944 American and British fire control systems as a whole were so incredibly advanced compared to those from just a year prior that its really astounding. You have the new Fast Battleships turning in long range battle practice cards with 18% hit rates (a quick check at 1930s long range battle practices turns in about 2-3% on average with aerial spotting) at an average distance of 29,000 yards, in a sea rough enough to be rolling the firing ship by fifteen degrees and running the guns into their elevation stops.

The complexity and accuracy achieved by analog systems really is astounding. To speak nothing about the advancements into shipboard jamming systems and other early ECM.

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12 hours ago, LT_Rusty_SWO said:

It's also a load of excrement from a male bovine.

You don't just stop that much steel in the middle of the ocean...

Where did you see that? I'm just seeing it say you can't fire and maneuver at the same time,  not that you can't fire and sail in a straight line at the same time. 

Or, maybe the author was a consultant for Steel Ocean...:Smile_teethhappy:

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12 hours ago, LT_Rusty_SWO said:

It's also a load of excrement from a male bovine.

You don't just stop that much steel in the middle of the ocean and then aim and fire and then start up again.

Jesus. That's one of the most idiotic concepts I've ever heard.

You have rangefinders and such, and do maneuvering boards to figure out not only where your target is at relative to you, but what your relative position will be at the end of the shell's TOF assuming nobody maneuvers, and then you point the guns there. By the time Yamato came around, they had automatic analog stuff, electrical "computers" of sorts, that used cam wheels to automagically compute lead, based on input from the director. It doesn't matter if it's radar or just optical, the link between the turret and the director is still automatic.

There was no such thing as stop-and-fire in naval warfare.

ever.

Are you referring to the Yamato systems as automagic? I think the stop to shoot sounds fishy too. Perhaps the Iowa had even better automagic that allowed for radical emergency maneuvers while firing while the Yamato had to hold a course and possibly slow downfor some period of time in order to bring turrets around and plot firing solutions? Not being argumentative at all, genuinely interested in how these ships stacked up.

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8 hours ago, _RC1138 said:

To those curious, the reason they could not shoot and maneuver is that, at that time, Combat Fire Control Computers relied on Constant Bearings to get firing solutions. It doesn't matter exactly WHAT that bearing is, but it must remain constant. If you, or your target for that matter, change bearing, there was no way at that time for 90% of ships to account for this change in direction and thus, the computer cannot get a firing solution.

The reason the USN (it was not just the Iowa's that were capable of this, all ships from the New Mexico class, on, were capable of firing and maneuvering) and the Royal Navy, (and *only* these two Navies, for a key reason), from the Nelsons, on (although they retrofitted the QE's and R Classes (and the R Class CC's as well) but not the Hood, interestingly, could do so was that their steering gears were not direct control. By that I mean, these ships were all 'fly by wire' when it came to rudder course modifications. See there are these things in control science called "PID's"  Controllers which stands for Proportional Integral Derivative Controllers. In laymen terms... how best to describe this...

So okay, most people know how a standard, home oven works right? You set it to a temperature, say 350 Degrees Fahrenheit. To reach that temperature the heating elements turn on. Not turn on to 50% their heating capacity, not turn on to 75% heating capacity and throttle down as it approaches the set point, they just turn on, full blast, 100%. Once the thermometer inside the oven reads 350 degrees, they turn off, and the temperature wobbles (in control terms, "Perturbates" ) around that set point as the elements turn on and off. If you graphed the temperature, it would just look like a sine curve, just wobbling above and below the set point and in reality spending VERY little time *at* the desired set point. This is (sorta) fine in an oven, but on a ship, trying to shoot another ship, where a single degree off could result in an overshoot/undershoot of 100's of meters, these lack of accuracy in control of bearing causes HUGE problems when trying to fire while maneuvering.

A PID Controller (along with other types of controllers) work a bit more exactingly/accurately. Instead of turning on the elements 100% on till a set point is reached, it turns on say, 75%, until it reaches 300 degrees, then turns down to say 25%, and when it reaches 340 degrees, down to 15%, and incrementally down till it maintains at 350. In control theory, 'overshoot' is where you exceed that set point, and have to fall back into it (on the first 'wobble'). PID's seek to minimize that Overshoot as much as possible (to the point where it 'effectively' does not exist) and to reduce 'noise' in the system after that point. They are slower to react, for the obvious reasons, but FAR more accurate and *super* predictable (so that you can say, base a calculation not on where you are in that control curve, but where you will BE at x deltaTime in the future).

PID_varyingP.jpg

These are all graphs of a controlled process, the one that you would *want* is the Red line, as it slides into the set point (1) gently and gradually and, importantly, Predictably, with minimal (none) overshoot. That first 'bump' that the green and purple have is the overshoot, and the Blue line would be what we call a step change ('instantaneous' change, like flipping a switch on a circuit)

This matters in this context because the *first* PID's ever to be used were fitted to Battleships, specifically the New Mexico class to control the rate of turn on the ship's rudder. Initially, so that ships would slide into a turn smoothly without overshooting and having to steer 'back' to the desired bearing. But this had the EXTRA effect of making their own maneuvers HIGHLY consistent and most importantly, predictable. When the Ford Mk1 Computer came out, this data was fed into it as one of the control points that allowed USN Battleships (or any ship fitted with a PID controlled rudder (and later, many other parts of the ship were placed under PID/PI Control)) to maneuver while firing because their own changes in bearing could immediately be accounted for and predicted. The Royal Navy also adopted these and were also capable of firing and maneuvering (as shown during the Final Battle of the Bismarck/Final Battle of the Scharnhorst)

HOWEVER this *only* applied the ship itself, not it's target. So if a target being fired at was rapidly changing it's bearing, the Mk1, and subsequent WWII era computers COULD NOT in real time predict the new firing solution, and would require the target to stabilize. This wasn't a problem because, as stated, NO OTHER enemy nation was capable of firing while maneuvering, and thus, you were 'safe' waiting for them to stabilize.

 

Freaking awesome post. Thank you.

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It wouldn't matter anyways.  By the time the Iowa-class entered service, the US Navy was ROLLING DEEP.

"You get a Carrier!"

"You get a Carrier!"

"You too get a Carrier!"

"Hey!  You guys there!  You want a Carrier?... Here you go!"

"You get a... What?  You want Battleships instead?  FINE!  We just made a couple, here, have 6 new ones we just had laying around!  We'll even throw in a complimentary few dozen Destroyers on top of the giveaway!"

"Our friends across the Atlantic needed some Destroyers, so we sent, like, a hundred or something like that."

200.gif

In mid 1943, the American Naval Steamroller was rolling downhill already and there were no brakes to stop for anyone.

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2 minutes ago, Skpstr said:

Where did you see that? I'm just seeing it say you can't fire and maneuver at the same time,  not that you can't fire and sail in a straight line at the same time. 

Or, maybe the author was a consultant for Steel Ocean...:Smile_teethhappy:

It's been a while since I read the article, and I think I was mixing OP's statement about tanks in with it.

 

13 hours ago, RevTKS said:

Anyway, that quote blew me away. I knew that generally WWII era tanks could move or shoot, not both. It had not occurred to me that a warship would not be able to conduct maneuvers while attempting to fire (or achieve a firing solution).

 

 

 

1 minute ago, thebigblue said:

Are you referring to the Yamato systems as automagic? I think the stop to shoot sounds fishy too. Perhaps the Iowa had even better automagic that allowed for radical emergency maneuvers while firing while the Yamato had to hold a course and possibly slow downfor some period of time in order to bring turrets around and plot firing solutions? Not being argumentative at all, genuinely interested in how these ships stacked up.

 

To a limited extent, they were all automagic by this point, though some were more limited than others. The electromechanical control systems that slaved the turrets to the directors were remarkably sophisticated precision instruments, considering the technology of the day.

 

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Just now, LT_Rusty_SWO said:

It's been a while since I read the article, and I think I was mixing OP's statement about tanks in with it.

 

 

 

 

To a limited extent, they were all automagic by this point, though some were more limited than others. The electromechanical control systems that slaved the turrets to the directors were remarkably sophisticated precision instruments, considering the technology of the day.

 

Neat stuff. I read all the posts and have a better appreciation of the era now. As someone who always liked mechanical things more than electronic, steam over diesel and props over jets this “feels good”. Thanks.

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8 hours ago, _RC1138 said:

To those curious, the reason they could not shoot and maneuver is that, at that time, Combat Fire Control Computers relied on Constant Bearings to get firing solutions. It doesn't matter exactly WHAT that bearing is, but it must remain constant. If you, or your target for that matter, change bearing, there was no way at that time for 90% of ships to account for this change in direction and thus, the computer cannot get a firing solution.

The reason the USN (it was not just the Iowa's that were capable of this, all ships from the New Mexico class, on, were capable of firing and maneuvering) and the Royal Navy, (and *only* these two Navies, for a key reason), from the Nelsons, on (although they retrofitted the QE's and R Classes (and the R Class CC's as well) but not the Hood, interestingly, could do so was that their steering gears were not direct control. By that I mean, these ships were all 'fly by wire' when it came to rudder course modifications. See there are these things in control science called "PID's"  Controllers which stands for Proportional Integral Derivative Controllers. In laymen terms... how best to describe this...

So okay, most people know how a standard, home oven works right? You set it to a temperature, say 350 Degrees Fahrenheit. To reach that temperature the heating elements turn on. Not turn on to 50% their heating capacity, not turn on to 75% heating capacity and throttle down as it approaches the set point, they just turn on, full blast, 100%. Once the thermometer inside the oven reads 350 degrees, they turn off, and the temperature wobbles (in control terms, "Perturbates" ) around that set point as the elements turn on and off. If you graphed the temperature, it would just look like a sine curve, just wobbling above and below the set point and in reality spending VERY little time *at* the desired set point. This is (sorta) fine in an oven, but on a ship, trying to shoot another ship, where a single degree off could result in an overshoot/undershoot of 100's of meters, these lack of accuracy in control of bearing causes HUGE problems when trying to fire while maneuvering.

A PID Controller (along with other types of controllers) work a bit more exactingly/accurately. Instead of turning on the elements 100% on till a set point is reached, it turns on say, 75%, until it reaches 300 degrees, then turns down to say 25%, and when it reaches 340 degrees, down to 15%, and incrementally down till it maintains at 350. In control theory, 'overshoot' is where you exceed that set point, and have to fall back into it (on the first 'wobble'). PID's seek to minimize that Overshoot as much as possible (to the point where it 'effectively' does not exist) and to reduce 'noise' in the system after that point. They are slower to react, for the obvious reasons, but FAR more accurate and *super* predictable (so that you can say, base a calculation not on where you are in that control curve, but where you will BE at x deltaTime in the future).

PID_varyingP.jpg

These are all graphs of a controlled process, the one that you would *want* is the Red line, as it slides into the set point (1) gently and gradually and, importantly, Predictably, with minimal (none) overshoot. That first 'bump' that the green and purple have is the overshoot, and the Blue line would be what we call a step change ('instantaneous' change, like flipping a switch on a circuit)

This matters in this context because the *first* PID's ever to be used were fitted to Battleships, specifically the New Mexico class to control the rate of turn on the ship's rudder. Initially, so that ships would slide into a turn smoothly without overshooting and having to steer 'back' to the desired bearing. But this had the EXTRA effect of making their own maneuvers HIGHLY consistent and most importantly, predictable. When the Ford Mk1 Computer came out, this data was fed into it as one of the control points that allowed USN Battleships (or any ship fitted with a PID controlled rudder (and later, many other parts of the ship were placed under PID/PI Control)) to maneuver while firing because their own changes in bearing could immediately be accounted for and predicted. The Royal Navy also adopted these and were also capable of firing and maneuvering (as shown during the Final Battle of the Bismarck/Final Battle of the Scharnhorst)

HOWEVER this *only* applied the ship itself, not it's target. So if a target being fired at was rapidly changing it's bearing, the Mk1, and subsequent WWII era computers COULD NOT in real time predict the new firing solution, and would require the target to stabilize. This wasn't a problem because, as stated, NO OTHER enemy nation was capable of firing while maneuvering, and thus, you were 'safe' waiting for them to stabilize.

 

It's like the guys that poured in so much development into Radar got advanced perks for doing so.

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1 hour ago, Big_Spud said:

By mid 1943-early-1944 American and British fire control systems as a whole were so incredibly advanced compared to those from just a year prior that its really astounding. You have the new Fast Battleships turning in long range battle practice cards with 18% hit rates (a quick check at 1930s long range battle practices turns in about 2-3% on average with aerial spotting) at an average distance of 29,000 yards, in a sea rough enough to be rolling the firing ship by fifteen degrees and running the guns into their elevation stops.

The complexity and accuracy achieved by analog systems really is astounding. To speak nothing about the advancements into shipboard jamming systems and other early ECM.

It wasn't even just mid-1943; in the 30's the USN had *very* advanced fire control on Capital Ships and then retrofitted MOST older warships to be up to spec.

53 minutes ago, HazeGrayUnderway said:

It's like the guys that poured in so much development into Radar got advanced perks for doing so.

Not sure what that had to do with radar. I mean yes, Radar was important and advanced, but using a PID controller to make maneuvering consistent, predictable, and thus something you can model, develop a cam/differential for an FCS computer is a totally different set of tech.

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14 hours ago, RevTKS said:

Referring to Iowa's test firing under extreme maneuvers: “This was a much better performance than other contemporary systems,” he continues, “and gave U.S. battleships a major tactical advantage, in that they could both shoot and maneuver, whereas their opponents could only do one or the other.” 

This is a quote from this article http://nationalinterest.org/blog/the-buzz/heres-what-would-happen-if-the-2-most-powerful-battleships-25670?page=2

(it has several sections that repeat, or it could be a browser issue)

Anyway, that quote blew me away. I knew that generally WWII era tanks could move or shoot, not both. It had not occurred to me that a warship would not be able to conduct maneuvers while attempting to fire (or achieve a firing solution). Probably just me being a bit of a dolt, but I found that interesting. 

Also, the article doesn't give us much info on who would win between the two big girls. The author gives a slight advantage to Iowa, but states that all it would take is one or two 'lucky' shots to doom Iowa...and if those shots were early, well quick game over. 

 

 

An interesting video delving into night gunnery and night naval combat...well worth your time if you're into studying naval History: "Night Engagement off Empress Augusta Bay (1945) US Navy (Battle of Empress Augusta Bay)"  Its available on youtube.

 

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