Jura The idiot
General
I'll remember the last sentence: referring to 16" guns fire "An outstanding case where it's better to give, than to receive." LOL
I liked the ramming part, very short, starts at 06:18
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I'll remember the last sentence: referring to 16" guns fire "An outstanding case where it's better to give, than to receive." LOL
I liked the ramming part, very short, starts at 06:18
chuck731 are you absolutely sure it was 50:50? I quote from Campbell (end of p. 179): "Of the total of 100 per gun, 60 were stowed in the shell handling rooms in the revolving structure, and 40 in the shell room on the same level as the lower handling room, that is immediately below the main armour deck in 'B' and 'Y' and a deck lower in 'A'. In action, the guns would be supplied from the lower handling room and then from the upper one. Transfer from the shell room by push-pull gear and shell bogie was slower than supply by the hoists so that the handling rooms would be replenished between actions. It may be noted that the upper handling room could be filled only via the lower room and auxiliary or main hoists." end of typing
It might be 60:40, I am speaking from memory. The point is Yamato didn't have its entire ammunition complement readily available for a single intense engagement.
Jura The idiot
General
chuck731 concerning this
and also what you've said in your preceding post http://www.sinodefenceforum.com/mil...-startegy-discussions-15-6728.html#post268006 I have a question: what you think would've been the optimal speed of Japanese battleships (had they stayed in the range you suggested) ??
and also what you've said in your preceding post http://www.sinodefenceforum.com/mil...-startegy-discussions-15-6728.html#post268006 I have a question: what you think would've been the optimal speed of Japanese battleships (had they stayed in the range you suggested) ??
The fastest they can go, which before they take any damage is about 27.5 knots if they have clean bottoms and recently maintained engines, ~27 knots if they are in average condition envisioned in their design specs. Less if the sea is rough and the cruisers have trouble keeping up.
The American squadron with the 2 Iowas can securely attain 32.5 knots in most conditions. So the Japanese needs to go as fast as they can to lessen American advantage. The American squadron with the South Dakota would likely not be able to quite hit 27 knots, maybe 26 knots because South Dakota.
One unclear issue is vibration. Some battleships suffer vibration issues when running near top speed. This hampers their gunnery near top speed. In really bad cases, such as North Carolina class, the gunnery equipment become unuseable near nominal top speed of 28 knots, and realistic top fighting speed is only 23 knots. I believe South Dakota and Iowa classes also experienced vibration problems near top speed due to adverse interaction between their skegs and their propellers. I don't know of any references about whether the Yamato class also suffered vibration problems. Vibration problems may well limit some or all of these ships from fighting a surface action effectively near their nominal top speeds.
Jura The idiot
General
Yes, I thought (but didn't say ;-) this would a logical conclusion out of your posts I quoted, and IN THEORY (I mean based on the information in Campbell's book) "the Type 98 (1938) Director, Computer and Sokutekiban" installed on Yamato-class should NOT have a problem: "Limits were measured range 50000 m, gun range 41300 m, deflection 130 mils R, 160 L, deflection in azimuth 500 mils, own speed 35 knots, target speed 40 knots, wind speed 40 m/s." I wonder how the performance of Japanese fire-control would have been affected by combat at max. speed (possibly bracketed by 16" projectiles etc.) ...
This is a forum and we are all entitled to our own believes and is free to forward our own arguments.I beg to disagree. The Yamato-class was a strategic weapon, expected to be superior in the decades to come ("superior" in the sense of being armed with, and partially protected against, the biggest naval guns of 1940s and likely up to 1950s; now I quote from p. 178 Conway's Fighting Ships 1922-1946: "Protection was designed to give immunity against 18" shells between 22000 and 33000 yards, and against a 1 ton bomb dropped from 15000 feet.") My point is they (I'm talking about a task force consisting of Yamato and Musashi) should have been used aggressively to get close to ANY battleship force of 1944 and ride it down
You quote maximal speeds. I doubt Yamato, Musashi would have achieved 1.0 percentage of hits at high speed (25+ knots) at long range (25+ kilometers).
I think majorly, what something is designed to do doesn't mean that it can be done; and also it is a question of reality. Maybe the Yamato and Mushashi can ride down a US BBBG of 3 Iowas + 1 SD; but this would also mean that the japanese fleet would likely be heavily damaged and would ineffect be sunk by allied planes, submarines and destroyers after the battle - like a lot of the damaged Japanese ships being finished off by allied subs.
The Yamatos are designed for a Mahan style massive total engagement where the victor keeps the field and can drag their damaged ships and capture their enemy's damaged ships. This case was never present in the pacific war.
So it is hard pressed for Japanese admirals to risk wining a battle to lose the war more quickly. I am sure a lot of them would wish for the glory in battling the american battle fleet, but at the back of their minds, they must know that the USA can lose those battleships and would have fresh ones replace them the next year; Japan cannot replace any one which they lose. Therefore, why not chose a safer option?
I don't know if the yamato was stable at max speed for gun fire. But it had a bulbous bow... and inherently bulbous bows are only useful and can only be optimized for high speed stability. i.e. the ship will be less stable at lower speeds (the wake acting on the bow is spit between pushing the blub down and the bow up; while the bulb provides more buoyancy (which at lower speed will dominate over the wave effect). While the clipper bow will keep pushing up the bow at speed inducing a cyclic vibration while at lower speed, it doesn't have the large bouyancy generation to induce as large vibrations). This would suggest that the Yamato class would be a good gun platform at maximum speed.
Much of vibration experienced at high speed often arises from resonance between hull structure and cyclic variations in thrust resulting from propeller turning in disturbed water behind the ship. All three classes of American battleships built during the war had issue with this. The builders attempted to address this issue by changing the number of blades on their propellers in order change the frequencies of cyclic thrust variation. This is how American battleships, somewhat uniquely, ended up with different number of blades on their inboard shafts than outboard shafts.
The vibration problem can be very severe and makes gunnery nearly impossible at high speeds. In the North Carolina class, designed for 28 knots, the vibration problem limited the ship to 26 knots for maneuvering except during absolute emergencies, and to 23 -24 knots when exercising gunnery.
South Dakota class also experienced propeller resonance induced vibration problems, although I've not heard it is as severe as in the North Carolina class. But although designed for only 27 knots while having more engine power than either the North Carolina or British KGV, both of which were the same size and capable of reaching higher speeds, South Dakota class is nonetheless unable to reach their designed top speed in service due to poor hull form.
Iowa class also experienced similar vibration problems at the beginning. But the problem seems to have been brought under control by change of propellers.
I've not found any record of whether Yamato suffered similar problems. American BB of WWII era shared a unique after body design with skegs housing some of the propeller shafts. The wake of disturbed water shed by the skegs interacting with propellers turning immediately behind them is thought to have caused much of the problem. Yamato had a fairly conventional after body design. So Yamato might have escaped serious vibration issues at the stern during high speeds.
The vibration problem can be very severe and makes gunnery nearly impossible at high speeds. In the North Carolina class, designed for 28 knots, the vibration problem limited the ship to 26 knots for maneuvering except during absolute emergencies, and to 23 -24 knots when exercising gunnery.
South Dakota class also experienced propeller resonance induced vibration problems, although I've not heard it is as severe as in the North Carolina class. But although designed for only 27 knots while having more engine power than either the North Carolina or British KGV, both of which were the same size and capable of reaching higher speeds, South Dakota class is nonetheless unable to reach their designed top speed in service due to poor hull form.
Iowa class also experienced similar vibration problems at the beginning. But the problem seems to have been brought under control by change of propellers.
I've not found any record of whether Yamato suffered similar problems. American BB of WWII era shared a unique after body design with skegs housing some of the propeller shafts. The wake of disturbed water shed by the skegs interacting with propellers turning immediately behind them is thought to have caused much of the problem. Yamato had a fairly conventional after body design. So Yamato might have escaped serious vibration issues at the stern during high speeds.
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Jura The idiot
General
Thank you, Lezt, now I like more what you said than that armchair admiraling I posted yesterday
I should be more careful and always try to separate what we all know that actually happened (I mean how easy it was to sink first Musashi and then Yamato by air attacks) from the information the Japanese might have ...
Jura The idiot
General
Once again I'll go back to the Battle of Calabria
A credible source says: 1. the HMS Warspite, max. speed 23.5 knots, was doing 15 knots while shooting at Guilio Cesare, and after increasing speed to 17 knots and performing 20 degrees turn, new firing solution had to be obtained;
2. Guilio Cesare, max. speed 27 knots, was doing 23 knots while shooting at Warspite, and was capable of directed fire up to only 25 knots.
Sure I know these were (refurbished) WW1-era battleships, and that a huge progress has been made during the course of the WW2, but ...
1. just one hit was obtained (out of 120+74=194 shots fired; 0.5%) and 2. it seems to me the visibility was as good as it gets on any July 9 in the Med sea ...
so it's hard for me to believe Yamato, Musashi at full speed would have scored the percentage chuck731 described in: http://www.sinodefenceforum.com/mil...-startegy-discussions-15-6728.html#post268033 (5 to 10 times higher ... I don't think British and Italians gunners were that sloppy
after a couple of salvos, many splashes were pretty close to either ship).But maybe you think I'm mixing apples with oranges here
just tell me, thanksOnce again I'll go back to the Battle of Calabria
1. the HMS Warspite, max. speed 23.5 knots, was doing 15 knots while shooting at Guilio Cesare, and after increasing speed to 17 knots and performing 20 degrees turn, new firing solution had to be obtained;
2. Guilio Cesare, max. speed 27 knots, was doing 23 knots while shooting at Warspite, and was capable of directed fire up to only 25 knots.
Sure I know these were (refurbished) WW1-era battleships, and that a huge progress has been made during the course of the WW2, but ...
1. just one hit was obtained (out of 120+74=194 shots fired; 0.5%) and 2. it seems to me the visibility was as good as it gets on any July 9 in the Med sea ...
so it's hard for me to believe Yamato, Musashi at full speed would have scored the percentage chuck731 described in: http://www.sinodefenceforum.com/mil...-startegy-discussions-15-6728.html#post268033 (5 to 10 times higher ... I don't think British and Italians gunners were that sloppy
But maybe you think I'm mixing apples with oranges here
Whether going at full speed impact a great deal on the ship's gunnery really depends on how prone the particular ships are to vibration at high speed. Battle of Denmark Strait was fought by Hood and Prince of Wales at 27 - 28 knots, at the maximum speed of POW. Bismarck also fought at 26+ knots, when Bismarck's gunnery was very good. I believe refitted Warspite had the same Admiralty fire control table as the new Prince of Wales, so at least the fire control computer onboard the Warspite should be able to handle 23.5 knots. I don't know about her vibrations.
Warspite is known to suffer from a bum rudder during her entire service life. Her steering was highly liable to malfunction whenever she attempts to maneuver at high speed. She was almost destroyed in Jutland because of this. But it was never rectified despite 2 major modernizations. So that puts an restriction on how fast the British squadron can go to ensure Warspite wouldn't suddenly sheer out of line with a jammed rudder.
Whether a ship should be pushed to her maximum speed also depends on the state of the ship's engines. A ship that is new or freshly out from a thorough engine overhaul can be pushed to near maximum speed, sea state permitting, with relatively little risk of major machinery breakdown. A ship that has seen hard service for several years since the last major engine overhaul is likely unable to reach her top speed, or could only reach it with significant danger of major malfunction, or at least danger of rapid degradation of engine performance.
Also how fast a ship can go also depends on the cleanliness of the hull and the temperature of sea water. A ship operating in warm water for a year would need to discount her maximum speed by about 1 knots due to fouling of her hull by marine growth. A ship can usually go faster to colder water than in warmer water becasue condensors operates less efficiently in warmer water and thus the engine can develop less power. This could also amount to a difference of about 1 knot between North Atlantic and water off Singapore, by Admiralty reckoning.
In all honesty Yamato never saw much hard service as she remained in port during much of the time when she didn't take part in major operations. Yamato did reached 28.07 knots on one of her post refit trials early in 1943, about 0.5 knot above her nominal design speed. But even so that is in the cold water off Japan with her hull freshly cleaned and her engines still almost new. I don't know when the last time was when she had her hull cleaned before Sumar. There was a major dockyard stay at the end of 1943 to repair damage from a torpedo hit. That might be the last time she had her hull thoroughly cleaned. So by end of 1944 she would have accummulated a years's worth of marine growths on her bottom and be swimming in milk warm sea off phillipines. So I might guess her practical maximum speed at the end of 1944 is not much more than 26 knots.
The problem with the American group is however the Americans split their forces, each group is limited to the slowest ship, which in turn depends individual history of the ships in the group. I don't know for sure, but I suspect South Dakota had by this time already steamed considerably more miles than the Yamato. We know South Dakota is only good for 26 knots at most even with clean hull, as post refit dockyard trials near the end of the war seem to show. So in practice she might be good for only 24-25 knots even without considering vibration problem.
The three Iowas were almost brand new, so they might achieve closer to their rated top speed of 33 knots, say ~32 knots to account for warm water in the battlezone.
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