D’Eyncourt possibly preferred twelve 15-inch guns in four triple turrets (about the equivalent of eight 18-inch guns - almost), but the amount of internal space Oram took meant that, to have that armament, would require additional lengthening of the ship for the additional magazine space required.
As for Renown, I was thinking of the poor deck protection and lack of adequate torpedo bulkheads caused by the excessive machinery weight. Small tube boilers and geared turbines would have saved 2,900 tons of weight which would have gone a long way to rectifying these shortcomings. The reduction to 3 boilers rooms (120,000shp) from 5½ boiler rooms (112,000shp) would have compacted the citadel considerably, substantially reducing the volume of hull that needed protecting; which all suggests that Renown could have been built as a more decently protected ship of even higher speed and would not have to had to be weighed down by extra armour when preparing to commission in the post Jutland era. Despite the extra armour weight, Renown still achieved 32.6 knots on trials. What speed would she have achieved with the both extra horses and completing with her design displacement?
The accepted story of Renown’s machinery arrangement, a story invented by d’Eyncourt (a story that covered Oram’s ass – d’Eyncourt was ever the Gentleman) when asked by the 1st Sea Lord in 1917 or 1918, is that, due to the fast paced and accelerated nature of the project, there was no time to develop an entirely new engineering layout and the pre-existing template of Tiger’s machinery layout had to be used.
The first problem with this story is that while Renown’s machinery arrangement is indeed developed from Tiger’s template, it is not a straight forward copy of it. Renown is completely oil fired while Tiger is dual fired (and this alone required considerable changes to the template), Renown had extra boilers requiring additional pipe runs (both fuel and steam that are not part of Tiger’s template), and the extra pressure and steam available required alterations to the turbine set-up to account for it. Basically, there was in fact considerable detailed work involved in adapting Tiger’s template to suit Renown: likely nearly as much if starting with a blank sheet of paper.
The second problem I see is due to the large numbers of Ships Covers that I have dipped into. I can see that developing a basic machinery arrangement template typically takes two to three days. Fisher’s project was fast paced, but not that fast paced. While obviously there is considerably more to do to evolve a basic template into a completed article, my point is that the amount of work the engineers need to do to allow constructors to design and begin building a ship takes a very small amount of time. The engineers can do the detailed work once the constructors have received the basics from them and therefore, any delay involved is minimal.
The third problem is that, even if I am totally wrong about the first two points above, templates for oil-fired, small-tube boilers and geared turbines arrangements already existed well before Fisher ever mentioned his Rhadamanthus project to d’Eyncourt: The light cruisers Calliope and Champion (and prior to them, if minus the geared turbines, the Arethusa’s and Caroline’s). If a pre-existing template was genuinely needed to push Renown along as fast as possible, there were several there to choose from, and none were used (The Courageous machinery arrangement is basically Champion’s arrangement doubled).
The two founding principles of the original Rhadamanthus project were very high speed and a displacement low enough to allow rapid construction of a hull around pre-existing 15-inch gun turrets. Any design attempting to achieve these necessities demanded a compact citadel to reduce displacement by reducing the area of armour coverage required to protect the vitals. Placing eight boilers in a single boiler room was common practice in dreadnought designs and when you compare twenty-four small tube boilers in 3 boiler rooms for 120,000shp against 42 large-tube boilers in 5½ boiler rooms for 112,000shp, it can be seen that what Oram chose to offer flew in the face of the requirements and was the key factor in the major design flaws inherent in the Renown’s.
Oram does not appeared to have cared if his machinery arrangements detracted from the battle-worthiness of Royal Navy warships. As long as they worked, were reliable, comfortable workplaces (i.e. not cramped) for his fellow mistreated engineers, and he took no risks that could come back to bite him, that seems to have been enough for Oram. If his excessive use of available displacement resulted in a ship that got blown out of the water on encountering an enemy, he could be reasonably certain that he could not be held responsible as he was not the decision maker that was responsible for building the ships in the first place. Adequate research into Oram is not there, but it is badly needed to try determine the truth of it all.
As I was skimming through the Renown’s ships cover to see if I could locate Oram’s memo, I noticed something I hadn’t before. I think I mentioned previously, at some point, that Fisher gave his initial requirements for the 4x15-inch gun Rhadamanthus on 18 December and on 19 December he revised the requirements to that which produced the 6x15-inch gun Renown. I had always assumed that the 4x15-inch gun version of Rhadamanthus was intended to be an armoured forerunner of the Large Light Cruisers for Baltic operations requiring the ability to transit the Danish Sound, but instead, Fisher decided to build more powerful units to instead reinforce the flawed battlecruiser force. However, data, that had previously escaped my notice, disproves this assumption. The new data I noticed are some scribbled calculations relating to the 4x15-inch gun design.
While it is well known that Fisher specified that the armour scheme for Rhadamanthus was to be that of Indefatigable, it is not well understood that Indefatigable was the basis for the whole design. The initial instruction from d’Eyncourt to his responsible minion was:
“Try for ship 630ft x 74/76 feet x 26/27 feet of 18,750 tons 32 knots with 105,000shp. Oil only. Armament 4x15” + 20x4” in open. Belt 6”-4”-3” as Indefatigable. Barbettes 2x8”7” as Indefatigable. Weights: Equipment - 700 tons. Armament - 2,200 tons. Machinery - 4,800 tons 5,100 tons. Oil – 700 tons. Armour – 3,000 tons 3,200 tons. Hull – 7,400 tons. = 18,800 tons [With the modifications 19,300 tons] Say 19,000 tons”
As this proved too ambitious, on the next sheet we have fresh calculations:
The above calculations show that Indefatigable’s original design displacement of 18,750 tons was initially being aimed at. This shows that a 32 knot, oil fired, Indefatigable with 4x15-inch (broadside weight 7,680lbs), instead of 8x12-inch (6,800lbs), is what d’Eyncourt understood to be what Fisher wanted. As the load draught displacement required for free passage of the Danish Sound is 24 feet, this 4x15-inch version of Rhadamanthus was clearly not intended for Baltic operations and the nominally similar Large Light Cruisers now have to be viewed as a project completely independent from Rhadamanthus. Therefore, it now seems almost certain that reinforcing the battlecruiser force had always been the primary aim of the Rhadamanthus project. With the available turrets, three (four if the 15-inch monitors are not a factor) of these ships could be built.
However, as can be seen from the calculations above, it proved impossible to get a 32 knot, armoured ship, armed with 4x15-inch guns on Indefatigable’s displacement; at least not with large-tube boilers and direct drive turbines. Small tube boilers and geared turbines would have reduced machinery weights to 2,290 tons, a saving of 2,910 tons, immediately reducing load displacement to 21,090 tons. Then there would be a further saving in displacement by the automatic reduction of the length of the machinery spaces; roughly by half. That is at least a further 2,000 tons reduction in displacement in reduced armour/protective plating; bringing the displacement down very near the originally sought displacement of 18,750 tons.
The original 4x15-inch Rhadamanthus could only have been a plausible design if small tube boilers and geared turbines were used. A possibility is that Fisher considered the 24,000 ton displacement as being too much ship for only 4x15-inch guns, and that this may be the reason why Fisher reissued the Rhadamanthus specification for a ship with 6x15-inch guns.
Fisher, from his writing, seemingly had no issues with facing off against a peer opponent in a ship to ship duel with only four guns, providing those four guns hit much harder than the more numerous guns equipping the opposition. This viewpoint has been severely criticised ever since by both naval professionals at the time and historians ever since; people who were not sitting in the hot seat, and who judge the situation, and the Man, without considering the wider context influencing Fisher’s viewpoint.
The primary influence behind Fisher’s viewpoint was that, in Fisher’s expert opinion, pre-war planning had failed, resulting in a shortfall of a critical ship type: heavy battlecruisers of the Lion type. The four Lion’s found themselves facing off against five German heavy battlecruisers (with a sixth in the pipeline against none for the Royal Navy). The Admiralty and C-in-C Grand Fleet tried to compensate for this enemy superiority of numbers by re-allocating the light battlecruiser force to the Grand Fleet.
However, this caused an immediate issue due to the differences in speed between the three British battlecruiser squadrons with the faster ships faced with the choice of sacrificing their speed advantage to remain within supporting distance of their slower sisters, thereby offering the enemy battlecruisers the opportunity to evade, or to choosing to try bring the enemy battlecruisers to battle with inferior numbers.
Another issue was that Fisher’s implementation of the battlecruiser concept in 1905 had intended that airships provide the scouting element for the battlecruisers. As a proper British airship scouting force had not materialised, and other aviation assets were still too primitive to undertake the role, small 2nd class cruisers were assigned the scouting role despite the fact they were slower than the fast capital ships they were scouting for and, in poor weather and sea conditions, their small, top-heavy hulls, lacked any ability to escape from any German battlecruisers they might stumble across. Something possessing far more high-speed seaworthiness and heavy gunpower was needed to both reinforce the faster heavy battlecruisers as well as replace the inadequate 2nd class scout force.
Any capital ship built by a nation at war has to have a clear beneficial return on the investment of scarce and in-demand resources; while also being a ship that could be built quickly. A 19,000 ton ship will be built quicker than a 24,000 ton ship, while placing considerably less demands upon the limited wartime resources. But there will come a point where diminishing marginal returns come to the fore when a project becomes no longer worth the costs of building it. As the 19,000 ton ship was not achievable, it possibly then became considered to be a greater return on investment to incorporate more firepower and go larger still, in this case to a 26,000 ton design with 6x15-inch guns.
A question that comes to mind here is: Would two valuable 15-inch turrets have been allowed go to monitors had the smaller 4x15-inch design proved feasible? Once the decision was made to go to a larger design with three twin 15-inch turrets, it was no longer possible to build more than two such units which resulted in two turrets being left over. So, from a potential four units, the potential program was reduced to two with two turrets left unused and available for other projects [Another possibility that must also be considered that Churchill may have simply claimed two 15-inch turrets for his monitors and that this possibility is what caused Fisher to opt for a 6x15-inch Rhadamanthus instead as he could no longer get four units for two squadrons of cooperating pairs – see concentration fire section below].
no subject
As for Renown, I was thinking of the poor deck protection and lack of adequate torpedo bulkheads caused by the excessive machinery weight. Small tube boilers and geared turbines would have saved 2,900 tons of weight which would have gone a long way to rectifying these shortcomings. The reduction to 3 boilers rooms (120,000shp) from 5½ boiler rooms (112,000shp) would have compacted the citadel considerably, substantially reducing the volume of hull that needed protecting; which all suggests that Renown could have been built as a more decently protected ship of even higher speed and would not have to had to be weighed down by extra armour when preparing to commission in the post Jutland era. Despite the extra armour weight, Renown still achieved 32.6 knots on trials. What speed would she have achieved with the both extra horses and completing with her design displacement?
The accepted story of Renown’s machinery arrangement, a story invented by d’Eyncourt (a story that covered Oram’s ass – d’Eyncourt was ever the Gentleman) when asked by the 1st Sea Lord in 1917 or 1918, is that, due to the fast paced and accelerated nature of the project, there was no time to develop an entirely new engineering layout and the pre-existing template of Tiger’s machinery layout had to be used.
The first problem with this story is that while Renown’s machinery arrangement is indeed developed from Tiger’s template, it is not a straight forward copy of it. Renown is completely oil fired while Tiger is dual fired (and this alone required considerable changes to the template), Renown had extra boilers requiring additional pipe runs (both fuel and steam that are not part of Tiger’s template), and the extra pressure and steam available required alterations to the turbine set-up to account for it. Basically, there was in fact considerable detailed work involved in adapting Tiger’s template to suit Renown: likely nearly as much if starting with a blank sheet of paper.
The second problem I see is due to the large numbers of Ships Covers that I have dipped into. I can see that developing a basic machinery arrangement template typically takes two to three days. Fisher’s project was fast paced, but not that fast paced. While obviously there is considerably more to do to evolve a basic template into a completed article, my point is that the amount of work the engineers need to do to allow constructors to design and begin building a ship takes a very small amount of time. The engineers can do the detailed work once the constructors have received the basics from them and therefore, any delay involved is minimal.
The third problem is that, even if I am totally wrong about the first two points above, templates for oil-fired, small-tube boilers and geared turbines arrangements already existed well before Fisher ever mentioned his Rhadamanthus project to d’Eyncourt: The light cruisers Calliope and Champion (and prior to them, if minus the geared turbines, the Arethusa’s and Caroline’s). If a pre-existing template was genuinely needed to push Renown along as fast as possible, there were several there to choose from, and none were used (The Courageous machinery arrangement is basically Champion’s arrangement doubled).
The two founding principles of the original Rhadamanthus project were very high speed and a displacement low enough to allow rapid construction of a hull around pre-existing 15-inch gun turrets. Any design attempting to achieve these necessities demanded a compact citadel to reduce displacement by reducing the area of armour coverage required to protect the vitals. Placing eight boilers in a single boiler room was common practice in dreadnought designs and when you compare twenty-four small tube boilers in 3 boiler rooms for 120,000shp against 42 large-tube boilers in 5½ boiler rooms for 112,000shp, it can be seen that what Oram chose to offer flew in the face of the requirements and was the key factor in the major design flaws inherent in the Renown’s.
Oram does not appeared to have cared if his machinery arrangements detracted from the battle-worthiness of Royal Navy warships. As long as they worked, were reliable, comfortable workplaces (i.e. not cramped) for his fellow mistreated engineers, and he took no risks that could come back to bite him, that seems to have been enough for Oram. If his excessive use of available displacement resulted in a ship that got blown out of the water on encountering an enemy, he could be reasonably certain that he could not be held responsible as he was not the decision maker that was responsible for building the ships in the first place. Adequate research into Oram is not there, but it is badly needed to try determine the truth of it all.
As I was skimming through the Renown’s ships cover to see if I could locate Oram’s memo, I noticed something I hadn’t before. I think I mentioned previously, at some point, that Fisher gave his initial requirements for the 4x15-inch gun Rhadamanthus on 18 December and on 19 December he revised the requirements to that which produced the 6x15-inch gun Renown. I had always assumed that the 4x15-inch gun version of Rhadamanthus was intended to be an armoured forerunner of the Large Light Cruisers for Baltic operations requiring the ability to transit the Danish Sound, but instead, Fisher decided to build more powerful units to instead reinforce the flawed battlecruiser force. However, data, that had previously escaped my notice, disproves this assumption. The new data I noticed are some scribbled calculations relating to the 4x15-inch gun design.
While it is well known that Fisher specified that the armour scheme for Rhadamanthus was to be that of Indefatigable, it is not well understood that Indefatigable was the basis for the whole design. The initial instruction from d’Eyncourt to his responsible minion was:
“Try for ship 630ft x 74/76 feet x 26/27 feet of 18,750 tons
32 knots with 105,000shp. Oil only.
Armament 4x15” + 20x4” in open.
Belt 6”-4”-3” as Indefatigable.
Barbettes 2x8”7” as Indefatigable.
Weights:
Equipment - 700 tons.
Armament - 2,200 tons.
Machinery - 4,800 tons 5,100 tons.
Oil – 700 tons.
Armour – 3,000 tons 3,200 tons.
Hull – 7,400 tons.
= 18,800 tons [With the modifications 19,300 tons]
Say 19,000 tons”
As this proved too ambitious, on the next sheet we have fresh calculations:
“735 x 80 feet x 27½ feet = 23,000 tons.
720 feet x 89 feet x 27½ feet = 24,500 tons.
Equipment - 750 tons.
Armament - 2,250 tons.
Machinery - 5,900 tons.
Oil – 900 tons.
Hull – 9,700 tons.
Armour - 4,500 tons.
= 24,000 tons – 108,000shp.
Tiger 28,800 tons – 105,800shp.”
The above calculations show that Indefatigable’s original design displacement of 18,750 tons was initially being aimed at. This shows that a 32 knot, oil fired, Indefatigable with 4x15-inch (broadside weight 7,680lbs), instead of 8x12-inch (6,800lbs), is what d’Eyncourt understood to be what Fisher wanted. As the load draught displacement required for free passage of the Danish Sound is 24 feet, this 4x15-inch version of Rhadamanthus was clearly not intended for Baltic operations and the nominally similar Large Light Cruisers now have to be viewed as a project completely independent from Rhadamanthus. Therefore, it now seems almost certain that reinforcing the battlecruiser force had always been the primary aim of the Rhadamanthus project. With the available turrets, three (four if the 15-inch monitors are not a factor) of these ships could be built.
However, as can be seen from the calculations above, it proved impossible to get a 32 knot, armoured ship, armed with 4x15-inch guns on Indefatigable’s displacement; at least not with large-tube boilers and direct drive turbines. Small tube boilers and geared turbines would have reduced machinery weights to 2,290 tons, a saving of 2,910 tons, immediately reducing load displacement to 21,090 tons. Then there would be a further saving in displacement by the automatic reduction of the length of the machinery spaces; roughly by half. That is at least a further 2,000 tons reduction in displacement in reduced armour/protective plating; bringing the displacement down very near the originally sought displacement of 18,750 tons.
The original 4x15-inch Rhadamanthus could only have been a plausible design if small tube boilers and geared turbines were used. A possibility is that Fisher considered the 24,000 ton displacement as being too much ship for only 4x15-inch guns, and that this may be the reason why Fisher reissued the Rhadamanthus specification for a ship with 6x15-inch guns.
Fisher, from his writing, seemingly had no issues with facing off against a peer opponent in a ship to ship duel with only four guns, providing those four guns hit much harder than the more numerous guns equipping the opposition. This viewpoint has been severely criticised ever since by both naval professionals at the time and historians ever since; people who were not sitting in the hot seat, and who judge the situation, and the Man, without considering the wider context influencing Fisher’s viewpoint.
The primary influence behind Fisher’s viewpoint was that, in Fisher’s expert opinion, pre-war planning had failed, resulting in a shortfall of a critical ship type: heavy battlecruisers of the Lion type. The four Lion’s found themselves facing off against five German heavy battlecruisers (with a sixth in the pipeline against none for the Royal Navy). The Admiralty and C-in-C Grand Fleet tried to compensate for this enemy superiority of numbers by re-allocating the light battlecruiser force to the Grand Fleet.
However, this caused an immediate issue due to the differences in speed between the three British battlecruiser squadrons with the faster ships faced with the choice of sacrificing their speed advantage to remain within supporting distance of their slower sisters, thereby offering the enemy battlecruisers the opportunity to evade, or to choosing to try bring the enemy battlecruisers to battle with inferior numbers.
Another issue was that Fisher’s implementation of the battlecruiser concept in 1905 had intended that airships provide the scouting element for the battlecruisers. As a proper British airship scouting force had not materialised, and other aviation assets were still too primitive to undertake the role, small 2nd class cruisers were assigned the scouting role despite the fact they were slower than the fast capital ships they were scouting for and, in poor weather and sea conditions, their small, top-heavy hulls, lacked any ability to escape from any German battlecruisers they might stumble across. Something possessing far more high-speed seaworthiness and heavy gunpower was needed to both reinforce the faster heavy battlecruisers as well as replace the inadequate 2nd class scout force.
Any capital ship built by a nation at war has to have a clear beneficial return on the investment of scarce and in-demand resources; while also being a ship that could be built quickly. A 19,000 ton ship will be built quicker than a 24,000 ton ship, while placing considerably less demands upon the limited wartime resources. But there will come a point where diminishing marginal returns come to the fore when a project becomes no longer worth the costs of building it. As the 19,000 ton ship was not achievable, it possibly then became considered to be a greater return on investment to incorporate more firepower and go larger still, in this case to a 26,000 ton design with 6x15-inch guns.
A question that comes to mind here is: Would two valuable 15-inch turrets have been allowed go to monitors had the smaller 4x15-inch design proved feasible? Once the decision was made to go to a larger design with three twin 15-inch turrets, it was no longer possible to build more than two such units which resulted in two turrets being left over. So, from a potential four units, the potential program was reduced to two with two turrets left unused and available for other projects [Another possibility that must also be considered that Churchill may have simply claimed two 15-inch turrets for his monitors and that this possibility is what caused Fisher to opt for a 6x15-inch Rhadamanthus instead as he could no longer get four units for two squadrons of cooperating pairs – see concentration fire section below].