The dreadnought project

[Fishey...)()]

http://www.dreadnoughtproject.org/

Not sure if this was linked to before, if not its well worth a look if your into dreadnought era weapon systems and PC simulations.

[Ironhand]

Great link:toast:

[Roberts]

http://www.dreadnoughtproject.org/

Not sure if this was linked to before, if not its well worth a look if your into dreadnought era weapon systems and PC simulations.

Utterly marvelous. But how would all that work as a game?

Simulating the Dreyer (which did not work all that well) seems like more of a challenge than simulating the Pollen (sp?) system...which did...

[Fishey...)()]

Utterly marvelous. But how would all that work as a game?

Simulating the Dreyer (which did not work all that well) seems like more of a challenge than simulating the Pollen (sp?) system...which did...


From his description in the movie section it seems the DFCT is pretty tough to get worked out. Nonetheless there is a 28min "Stand-in" movie on it.
I can't even imagine the diffulculties translating these systems into a PC Sim, hats off Mr.Lovell ..S!

[Commodore Rob]

I have been aware of this for a few years now, unfortunately I cant see much other then some nice CG models coming of this.

[tone]

Thanks for the kind words, all.

The Dreyer table did work fairly well, but the Royal Navy did not do very well when using it. The truth, I feel, is that the strengths of the device could only be achieved in conditions much unlike any North Sea naval battle was likely to impose. However, these same reasons I think would have made Pollen's Argo Aim Corrector gear fail sooner and more completely.

The majority of the Royal Navy's gunfire during the war was triggered by those crews enjoying the least practice and in visibility conditions inferior to those confronting the enemy's gunners. The Dreyer and Argo tables might have helped cover up this deficiency, but NOT when fed the quantity and quality of range, bearing and spotting data delivered to them at Jutland.

Pollen's equipment has enjoyed a longstanding "pass" on actual battle test, bolstered by an imposing tome by Prof. Jon Sumida called "In Defence of Naval Supremacy", a work which I feel bears with it the strengths and weaknesses to be expected in a work from the collator of the writings of Arthur Pollen. A recent counter-salvo by John Brooks in "Dreadnought Gunnery at the Battle of Jutland" reaches substantially different conclusions through an analysis centered on the mechanical design and function of these devices within their host ship.

I'd break the distinctions in the various fire control solutions down this way.

Argo's advantages:

1. A superior variable speed motor, whose speed could itself be continuously varied without slippage.
2. Great integration and superior tolerances for manufacture
3. Completely automated plotting table traced the actual courses of firing and target ship

Dreyer's advantages:

1. range plot amenable to plotting results from multiple range finders
2. (my opinion) range and bearing plots over time provided a better basis for actually solving fire control than merely plotting the courses of the two vessels (a tracing whose virtue lies largely in its appeal as a souvenir)

German system advantages:

1. rangefinders afforded a brighter image and their stereoscopic basis was more amenable to typical battle conditions
2. their lightweight fire control method did not require as much trend analysis, and therefore better at rapidly changing conditions without requiring time for derivatives to be gleaned from the data
3. amenable to allowing every rangefinder available to contribute to the data


Clouding most discussions are the following:

1. over-selling of Argo advantage #1 -- simple graphical anaysis performed by John Brooks demonstrates that altering the Dreyer's variable speed motor in discrete steps to accommodate its inability to be continuously altered never caused a meaningful discrepancy to be introduced.
2. Most people have been told Argo systems were helm-free and Dreyer gear was not. In fact, a gyrocompass's input ensured that the very first deployed Dreyer tables were independent of own ship's maneuvering. There remains, however, the smaller Dreyer Mark I table later crafted for early ships with small transmitting stations -- I do not think its design permitted gyro input.
3. No one mentions that the Argo plotting system could only allow a single rangefinder to supply data. As range estimates proved difficult to obtain regularly and were highly noisy, this is a critical fault.

I feel Beatty's poor shooting and the available record of the action shows that his transmitting stations were fed a thin diet of data that was largely erroneous. The fact that he did not accurately track range continuously when drawing upon the data supplied by his entire complement of rangefinding gear leaves me certain he would have done worse had he been obliged to employ a single rangefinder per ship as the Argo true-course plotter demanded. But unless one has great visibility and TIME to get several good observations of range and bearing on the table, no plotting-based system is going to prove very valuable, and this is clearly something the Grand Fleet never enjoyed. Even though some of Jellicoe's dreadnoughts turned in the best shooting of the entire engagement, the after action reports reveal they were shooting from the hip and that no useful plots were obtained in the majority case. Jellicoe's boys were simply good at gun drill, and freshly practiced.

Another mooting consideration in all this is naturally, "Why did the Germans outshoot the Brits when their system was essentially just to mean the cuts taken from all rangefinders?", and I think the answer is superior readiness in training and better visibility of the target for ranging and spotting.

edit: I checked back, and indeed the Mark I Dreyer tables were not helm-free. These were fitted in Dreadnought, Colossus, Hercules, Neptune, Collingwood, St Vincent, Agincourt, Erin, Bellerophon, Marlborough, Superb, Temeraire, Australia, New Zealand, and Inflexible. The Indomitable appears never to have had one fitted, and presumably the Invincible and Indefatigable carried Mark Is. By my count, that gives 3/10 ships of Beatty's squadron fire control tables that were not helm-free, and 12/27 of Jellicoe's ships these lesser tables (and one having nothing at all), though many of them shot well (probably not attributable to excellent tables, but...).

tone

[Roberts]

Thanks for the kind words, all.

The Dreyer table did work fairly well, but the Royal Navy did not do very well when using it. The truth, I feel, is that the strengths of the device could only be achieved in conditions much unlike any North Sea naval battle was likely to impose. However, these same reasons I think would have made Pollen's Argo Aim Corrector gear fail sooner and more completely.

tone

I'm only repeating what I've gleaned from Andrew Gordon's book and he seems to rely on Sumida completely.

However, it might be worth noting that the Queen Mary used the Pollen table. We don't knw how well it worked since she blew up.

Gordon (based on Sumida, I assume) says that after the war, RN ships used a device based on the Pollen Table and gave up the Dreyer.

I agree it is unwise to assume that the relatively few hits scored by the 2 squadrons of the BCF under Beatty's direct command had much to do with the Dreyer's short-comings. After all, the 5th BS used the Dreyer table and made hits at very long ranges under difficult conditions.

[tone]

I'm only repeating what I've gleaned from Andrew Gordon's book and he seems to rely on Sumida completely.

However, it might be worth noting that the Queen Mary used the Pollen table. We don't knw how well it worked since she blew up.


The Queen Mary actually had a Dreyer Table Mark II, which replaced the dumaresq and Dreyer/Elphinstone range clock with an Argo clock. This was a sound adaptation that drew upon the best of both worlds, though I concur with John Brooks view that the advantages of the Argo clock were unlikely to have delivered a measurable advantage to her. However, the Queen Mary appears to have shot better than her sisters (this was expected of her, as she was known as the best shooting ship, but I've not heard any direct tie made between her equipment and her shooting).


Gordon (based on Sumida, I assume) says that after the war, RN ships used a device based on the Pollen Table and gave up the Dreyer.


I'd have to re-read what I have on the Admiralty Fire Control Table which was designed right after the war.


I agree it is unwise to assume that the relatively few hits scored by the 2 squadrons of the BCF under Beatty's direct command had much to do with the Dreyer's short-comings. After all, the 5th BS used the Dreyer table and made hits at very long ranges under difficult conditions.

I truly believe that visibility and proficiency (as measured by means other than rapidity of fire) were the greatest determinants at Jutland. Even with her humble Dreyer Mark I, the freshly practiced crew of Invincible managed some of the best shooting by a battlecruiser that day. The Tiger's green crew, on the other hand, with a helm-free Dreyer Mark IV (or IV*) and fighting in conditions of unfavorable lighting and funnel smoke, hit doodly.

tone

[Daniel Sturgis]

Thanks for the kind words, all.

The Dreyer table did work fairly well, but the Royal Navy did not do very well when using it. The truth, I feel, is that the strengths of the device could only be achieved in conditions much unlike any North Sea naval battle was likely to impose. However, these same reasons I think would have made Pollen's Argo Aim Corrector gear fail sooner and more completely.

The majority of the Royal Navy's gunfire during the war was triggered by those crews enjoying the least practice and in visibility conditions inferior to those confronting the enemy's gunners. The Dreyer and Argo tables might have helped cover up this deficiency, but NOT when fed the quantity and quality of range, bearing and spotting data delivered to them at Jutland.

Pollen's equipment has enjoyed a longstanding "pass" on actual battle test, bolstered by an imposing tome by Prof. Jon Sumida called "In Defence of Naval Supremacy", a work which I feel bears with it the strengths and weaknesses to be expected in a work from the collator of the writings of Arthur Pollen. A recent counter-salvo by John Brooks in "Dreadnought Gunnery at the Battle of Jutland" reaches substantially different conclusions through an analysis centered on the mechanical design and function of these devices within their host ship.

I'd break the distinctions in the various fire control solutions down this way.

Argo's advantages:

1. A superior variable speed motor, whose speed could itself be continuously varied without slippage.
2. Great integration and superior tolerances for manufacture
3. Completely automated plotting table traced the actual courses of firing and target ship

Dreyer's advantages:

1. range plot amenable to plotting results from multiple range finders
2. (my opinion) range and bearing plots over time provided a better basis for actually solving fire control than merely plotting the courses of the two vessels (a tracing whose virtue lies largely in its appeal as a souvenir)

German system advantages:

1. rangefinders afforded a brighter image and their stereoscopic basis was more amenable to typical battle conditions
2. their lightweight fire control method did not require as much trend analysis, and therefore better at rapidly changing conditions without requiring time for derivatives to be gleaned from the data
3. amenable to allowing every rangefinder available to contribute to the data


Clouding most discussions are the following:

1. over-selling of Argo advantage #1 -- simple graphical anaysis performed by John Brooks demonstrates that altering the Dreyer's variable speed motor in discrete steps to accommodate its inability to be continuously altered never caused a meaningful discrepancy to be introduced.
2. Most people have been told Argo systems were helm-free and Dreyer gear was not. In fact, a gyrocompass's input ensured that the very first deployed Dreyer tables were independent of own ship's maneuvering. There remains, however, the smaller Dreyer Mark I table later crafted for early ships with small transmitting stations -- I do not think its design permitted gyro input.
3. No one mentions that the Argo plotting system could only allow a single rangefinder to supply data. As range estimates proved difficult to obtain regularly and were highly noisy, this is a critical fault.

I feel Beatty's poor shooting and the available record of the action shows that his transmitting stations were fed a thin diet of data that was largely erroneous. The fact that he did not accurately track range continuously when drawing upon the data supplied by his entire complement of rangefinding gear leaves me certain he would have done worse had he been obliged to employ a single rangefinder per ship as the Argo true-course plotter demanded. But unless one has great visibility and TIME to get several good observations of range and bearing on the table, no plotting-based system is going to prove very valuable, and this is clearly something the Grand Fleet never enjoyed. Even though some of Jellicoe's dreadnoughts turned in the best shooting of the entire engagement, the after action reports reveal they were shooting from the hip and that no useful plots were obtained in the majority case. Jellicoe's boys were simply good at gun drill, and freshly practiced.

Another mooting consideration in all this is naturally, "Why did the Germans outshoot the Brits when their system was essentially just to mean the cuts taken from all rangefinders?", and I think the answer is superior readiness in training and better visibility of the target for ranging and spotting.

edit: I checked back, and indeed the Mark I Dreyer tables were not helm-free. These were fitted in Dreadnought, Colossus, Hercules, Neptune, Collingwood, St Vincent, Agincourt, Erin, Bellerophon, Marlborough, Superb, Temeraire, Australia, New Zealand, and Inflexible. The Indomitable appears never to have had one fitted, and presumably the Invincible and Indefatigable carried Mark Is. By my count, that gives 3/10 ships of Beatty's squadron fire control tables that were not helm-free, and 12/27 of Jellicoe's ships these lesser tables (and one having nothing at all), though many of them shot well (probably not attributable to excellent tables, but...).

tone

When Beatty engaged the Scouting Group, he had 6 BC's (ie not including the relatively old Invincible, Indomintable and Inflexible, which were with Jellicoe) and the 5th BS, so he only had 2 non-helm-free tables (the New Zealand [I/]and the [I]Indefatigable)) at that point.

However this is all news to me, and I feel fortunate to have seen the quoted post. What are some good sources for what tables were on what ships in what time periods?

[tone]

When Beatty engaged the Scouting Group, he had 6 BC's (ie not including the relatively old Invincible, Indomintable and Inflexible, which were with Jellicoe) and the 5th BS, so he only had 2 non-helm-free tables (the New Zealand [I/]and the [I]Indefatigable)) at that point.

I believe this is the state of affairs.



However this is all news to me, and I feel fortunate to have seen the quoted post. What are some good sources for what tables were on what ships in what time periods?

The issue you raise of "what time periods" is a good one that is hard to answer. There is little information that can be found all in one place that is comprehensive in this regard, and notes on upgrades and swap-outs are generally scattered hither and yon.

However, the guard book for Dreyer Fire Control Tables which was assembled in 1918 has a nifty table showing which ships had which Mark. Typical of such things, however, the equipment of ships already lost is not noted anywhere. Making matters more quaintly muddled, some alterations to the printed table have been made by pencil, and some of the indicated equipment that seems mildly in the future (e.g.: Hood) is provisional. A lot of the problems arising in studying this period in this level of detail is gleaned by observing that when I say that Indomitable never had a Dreyer Table fitted, this is supported not by any positive assertion at all, but merely by her singular and conspicuous absence from this ONE table in this ONE source (of which there may only be a single extant copy?). How's that for history about to disappear over the brink?

Here is the data from the table, with my notes in parentheses, glossing over the non-dreadnoughts and non-battlecruisers:

Mark I table:
Dreadnought, Colossus, Hercules, Neptune, Collingwood, St Vincent, Agincourt, Erin, Bellerophon, Marlborough, Superb, Temeraire, Australia, New Zealand, and Inflexible. (infer: Invincible and Indefatigable, who are likely not listed as they were lost before this table was written)

Mark I* table: 6 assorted coast defence vessels and light cruisers under construction. This table DID use a gyrocompass to make it helm-free

Mark II: Ajax, Centurion, Conqueror, Orion (Queen Mary also known to have had one)

Mark III: King George V, Monarch, Thunderer (and gunnery schools Excellent and at Chatham)

Mark III*: 8 modern light cruisers. This was much like the original Mark III, but had an added device to help convert the speed across at the present gun range into a component of the deflection that will be sent on to the guns. The Mark III required more manual jiggering to effect this.

Mark IV: Queen Elizabeth, Benbow, Emperor of India, Iron Duke, Tiger. The Mark IV table introduced the "electrical dumaresq", which allowed it to automatically follow changes in range rate and deflection as its configuration changed. In all tables mentioned above, an operator had to manually twist knobs to follow these convolutions -- a fairly easy chore, but distracting from the other demands for attention.

Mark IV*: Resolution, Revenge, Royal Oak, Royal Sovereign, Barham, Malaya, Valiant, Warspite, Canada, Renown, Repulse, Lion, Princess Royal, Courageous, Glorious --- added in pencil are the following ships: Tiger, Ramillies, Queen Elizabeth, which imply that Tiger and Queen Elizabeth had Mark IV tables updated to Mark IV* standards at some point. The Mark IV* is identical to the Mark IV, except that its range plot is slightly wider and so supported ranges up to 28000 yards instead of 25000 yards.

Mark V: Ramillies, Anson, Hood, Howe, Rodney -- added by pencil: gunery schools at Chatham, Portsmouth and Devonport. From other sources, we know that Hood's 3 sisters here were never built and that she sported the only Mark V table ever taken to sea. By Ramillies being pencilled in under Mark IV*, we may guess that her outfit was altered before she ever had a Mark V fitted. The Mark V was similar to the Mark IV and IV*

Turret Control Tables (the play-at-home version of the Dreyer table for local turret control or use in light cruisers without room for a larger kit):
Ramillies, Resolution, Revenge, Royal Oak, Royal Sovereign, Barham, Malaya, Queen Elizabeth, Valiant, Warspite, Benbow, Emperor of India, Iron Duke, Marlborough, Renown, Repulse, Tiger, Courageous, Glorious and 6 light cruisers. These were emphatically not helm-free.

The Dreyers are difficult to fully appreciate and understand because the earliest handbooks have no surviving copies, and by the time the Mark III was encompassed in the 1918 handbook covering all models, all instances had been fairly heavily altered, especially in how they handled deflection, bearings and how range estimates were plotted.

tone

[Bullethead]

I truly believe that visibility and proficiency (as measured by means other than rapidity of fire) were the greatest determinants at Jutland. Even with her humble Dreyer Mark I, the freshly practiced crew of Invincible managed some of the best shooting by a battlecruiser that day.

I think Invincible's shooting was just the result of the much more favorable conditions under which she fired. Had any other ship been in her position, I believe it could have shot just as well.

Invincible was firing at only about 10kyds, practically point blank and very much less than the range Beatty had been dealing with all day. In addition, she was on the other side of the Germans from Beatty, so had the same lighting conditions advantage against the Germans as the Germans had against Beatty. In fact, the Germans couldn't see anything but her muzzle flashes for some time, which enabled Invincible to fire undisturbed by intervening splashes nearby or even the tension of being shot at. But when the Germans finally could see Invincible, they hit her just as easily as she hit them, thanks to the short range, and so blew her apart immediately.

[tone]

I think it possible that Invincible was just a good gunnery ship, but it is impossible to overstate the value (to any fire control team) of better visibility for rangetaking and for spotting, and Invincible clearly had this precious opportunity.

I'll try to reconstitute my effort to condense the sparse reporting from the gunnery officers when asked for a brain dump right after Jutland. I'd be curious how clearly Indomitable and Inflexible report the visibility they faced during this shooting spree.

tone

[SunScream]

Just to complicate matters even more, the Dreyer fire-control tables were only given their mark numbers late in the war and are not numbered in chronological order.
The MkIII appears to have been the basic starter model, from which was developed the MkIV and MkV. The Mk1 was a cut down model (for ships with less space?) which appears to have been developed at the same time as the MkIV. The MkII was a MkIII (or MkIV?) modified with the Pollen Argo clock.
The star variants are subsequent upgrades to the base models.

Really useful stuff, tone.
I know it is not something you are supposed to do to an old book - but any chance of a scan of the page? :yummy:

Tarrant in "Battlecruiser Invincible":
Invincible now found herself on a parallel course with the German battlecruisers, 9000 yards off the starboard beam. [..] At 6.26pm Invincible opened fire on Lutzow. Inflexible also concentrated her fire on Lutzow, while Indomitable ranged in on Derfflinger.
Twenty-one-year-old Marine gunner, Bryan Gasson, was at the rangefinder of Invincible's Q turret. [..] Lutzow was swathed in smoke and mist, but Gasson had a fairly clear view of her, magnified as she was twenty times in the stereoscopic sights of his rangefinder.
Within the next eight minutes Invincible scored eight hits on Lutzow at a range of approximately 9600 yards. It is estimated that she fired approximately fifty shells in this period. [..]
During the eight minute engagement, Invincible came under the concentrated fire of both Lutzow and Derfflinger. Range taker, Able Seaman Ernest Dandridge (in the foretop) recalls that: "The first German salvoes fell about 1,200 yards short, but they gradually fell closer until they were straddling Invincible, deluging the ship with shell splashes while pieces of shrapnel buzzed over the ship." A salvo hit the aft part of the ship but apparently caused no appreciable damage. A minute later, at 6.34pm a salvo from Derfflinger hit Invincible amidships (which was fatal).


Two of the hits scored on Lutzow did such devestating damage they can be considered the hits that sank her.
So maybe visibility was not entirely wonderful for Invincibles spotters, but yes, no doubt better than their German opponents.

[Daniel Sturgis]

Just to complicate matters even more, the Dreyer fire-control tables were only given their mark numbers late in the war and are not numbered in chronological order.
The MkIII appears to have been the basic starter model, from which was developed the MkIV and MkV. The Mk1 was a cut down model (for ships with less space?) which appears to have been developed at the same time as the MkIV. The MkII was a MkIII (or MkIV?) modified with the Pollen Argo clock.
The star variants are subsequent upgrades to the base models.



What are some sources for this information about the plotting tables?

[SunScream]

John Roberts' "Battlecruisers" Chatham Publishing 1997.
In Notes section for the chapter on gunnery, pg 126.

[tone]

What are some sources for this information about the plotting tables?

One good one is a 3 part article series in Warship International, circa 2002 by Bill Schleihauf. There are still back issues available: www.warship.org Also the recent book "Dreadnought Gunnery at the Battle of Jutland" by John Brooks, and a more afforable paperback edition is becoming available from Routledge..

tone

[tone]

Gordon (based on Sumida, I assume) says that after the war, RN ships used a device based on the Pollen Table and gave up the Dreyer.


Andrew Gordon is one of my favorite authors, but I can't say I agree with this assessment. I had to re-read an article on the Admiralty Fire Control Table, the machine that supplanted the Dreyer tables (to some degree... they only put it in newly completed battleships and cruisers, and merely updated the Dreyers already shipped) . They drew upon many fields of ideas and influence in making it.

First off, to share my sources, this is an article in the 2002-2003 edition of Warship by John Brooks entitled "The Admiralty Fire Control Tables". These tables took several years to be completed, and were substantially fancier than either the Argo or Dreyer tables had ever been, if tending to share the larger footprint of Dreyer equipment and taking it even beyond. It is hard to call them a "table" really... it is more a sort of dinette set of matching modular pieces, some essential (the dining table), and some optional (the grazing dish). The designers and contributors included both Dreyer's and Pollen's primary manufacturing and design people, Elphinstone and Isherwood, as well as influence or direct participation of various Dreyerites (Dreyer, Usborne, Hall, Henley) and various players often regarded as Dreyer detractors (Beatty, Chatfield).

Early documentation on the philosophy of the tables indicate that although they favored the general Dreyer-esque view that ranges and bearings should be plotted separately, and against time, that little hope should be retained for seeing a good range rate by plotting range versus time. Rather, more hope was placed in paying heed to measuring target inclination (the angle at which he appears to cross the line of bearing) to compute a range rate. But, over time as the devices were first built, ranges versus time with a few wrinkles appeared to have again taken a dominant role in the computation, albeit with some novel means allowing other sources of information to be taking into consideration for the best balanced determination of the target's activity.

The basic idea of range cuts being plotted discretely versus time as on the Dreyer table was blended with a latter-day Dreyer table mod which dumped the bearings-versus-time plot for plotting the difference between observed bearings and calculated bearings versus time (a method which allowed your width of paper to demonstrate a broader dynamic range of information) to produce a rangefinder range plot which plotted the difference between rangefinder cuts and the output of the range clock versus time. In this way, perfect results of rangefinders and fire control table team would produce simply a line up the middle of the sheet (zero difference), but otherwise you'd be plotting the apparent error between calculated and observed range, and the slope would indicate the error in the computeed range rate (if one trusted the range cuts were fairly good).

This range plot was combined with another one which showed the clock range and the gun range (gun range is clock range plus the current range spotting correction). Indeed, the complete AFCT Mark I had 5 paper plots (2 bearing, 3 range) in two separate compartments, along with a means of applying ranges reported by other ships in the formation as well as aircraft spotting corrections. It was fairly over-the-top (except by USN standards, where truly obscene advances were being made around this time). The only thing they wanted which basically never materialized was what distinguished USN systems: advanced gyroscopic inputs to counteract basically every rotational perversion the firing ship was subject to. The RN never really got gyros working as nicely as the Americans, I guess.

A reproduced page from an AFCT manual in this article shows that the enlarged AFCT-equipped TS had no fewer than 34 people working the equipment and its most proximate peripherals. Talk about leapfrogging technology!!

While all this is filtered through John Brooks's telling (his article is richly footnoted), I have to say that in all my dealings with him, and my ability to share his engineering eye for the actual capabilities and these machines, I trust that he has it spot on. Pollen's influence (to my eye) in the AFCT is that the Pollen/Isherwood variable speed drives used his ball-and-disc method rather than the Dreyer/Elphinstone wheel-and-disc method, and the dial-based visual indication of orientation of own and target ship resembled that of Pollen's AC clock more so than the abstract dumaresq offered in the Dreyer tables. But the reliance on visualization of real time data as separate plots of (some measure of) ranges and bearings versus time indicates to me that Dreyer's ideas more than held their own in influencing the future of RN fire control.

tone