Richelieu vs KGV

[boredatwork]

Bridges can fall when people are walking across them at a certain pace. (this was showed also in Mythbusters, IIRC )

Was that the episode with the 6 pairs of marching boots? =P

Back to our problem: I find it probable that the force of the blast was multiplied by the bottom.
However the scale of the explosion is very important: British aerial torpedoes of the period carried 180kg TNT warheads. Let's compare this to the 8 tons of Anatol (an explosive mixture far more powerfull than TNT) placed underneath Tirpitz's hull during operation Source.

From what I've read, the amount of damage was similar... And that despite the fact that Tirpitz suffered a blow 44 times the size of the one Richelieu had suffered

I will grant the charges in the Tirpitz attack were much more powerfull however balancing that none of them were in contact with the hull and 3 of 4 were over 50 yards away when they blew. Even then, from what I've read the Tirpitz was considerably more damaged than the Richelieu - though neither ship seemed disproportionately damaged for the force of explosions they were subjected to.

Also about JB: the damage suffered after 2x454kg bombs was much worse than the one suffered by Hiei in Nov 1942 after receiving at least 7 x 227kg bombs, and still worse than Nevada, who suffered 5 hits at Pearl Harbour.

What is your source for the comparisons? Was the damage from a 454kg more so than the individual damage of of a 227kg bomb? I wouldn't argue otherwise. What evidence is there though that JB suffered proportionally worse than either of the other ships?

[tommy303]

here is an interesting link to the damage report of the Nevada

http://www.history.navy.mil/docs/wwii/pearl/ph59.htm

[tommy303]

I seem to recall that the British had earlier attempted to immobilize Richelieu by dropping depth charges near the stern in an effort to damage her propellors and rudder (carried out by Lt-Cmdr Bristow of the HMS Hermes. Although the depth charges were successfully placed, some may not gone off due to the shallow depth of the water. It is possible that the torpedo hit may have caused the sympathetic detonation of one or more of these charges, resulting in damage all out of proportion to the size of the torpedo warhead.

[alecsandros]

Was that the episode with the 6 pairs of marching boots? =P

Yes :)

from what I've read the Tirpitz was considerably more damaged than the Richelieu - though neither ship seemed disproportionately damaged for the force of explosions they were subjected to.

Tirpitz remained afloat. It was repaired in 6 months on the spot , in NOrway, that is without the capacities of Hamburg or Wilhelmshaven. Richelieu, on the other hand, remained for 6 months in a very advanced repair facility.

If you will be kind enough to re-read the damage reports on the 2 ships, you'll find strikingly numerous similarities. Of course it wasn't exactly the same, but it was very close nonetheless.

And RIchelieu did suffer disproportionate damage for the force of the explosion. This is what I was telling all along. The ship sank by the stern. I have already posted the 2 page damage analysis of the ship. If that is not disproportionate in your opinion, wel... I guess we could end our discussion here, since we clearly have different ways of judging the event.

Also about JB: the damage suffered after 2x454kg bombs was much worse than the one suffered by Hiei in Nov 1942 after receiving at least 7 x 227kg bombs, and still worse than Nevada, who suffered 5 hits at Pearl Harbour.

What is your source for the comparisons? Was the damage from a 454kg more so than the individual damage of of a 227kg bomb? I wouldn't argue otherwise. What evidence is there though that JB suffered proportionally worse than either of the other ships?[/quote]

No source here. I was thinking about the brief damage analysis I've read and the pictures of NEvada steaming away from PH for repairs. I'm not fully certain about them, and that's why I did not insist on them.

@Thomas: yes, in G&D, this theory is presented. However, ading 1-2 depth charges to the equation can hardly explain the amount of damage the French ship suffered, especialy by comparison with Tirpitz. Moreover, this is just a theory, and not at all a certainty. The certainty is that a torpedo hit Richelieu...

[boredatwork]

Tirpitz remained afloat. It was repaired in 6 months on the spot , in NOrway, that is without the capacities of Hamburg or Wilhelmshaven. Richelieu, on the other hand, remained for 6 months in a very advanced repair facility.
[...]
I guess we could end our discussion here, since we clearly have different ways of judging the event.

You originally posted repair time as evidence of poor design. When I posted evidence that qualified that repair time you dismissed it as being irrelavent to the scenario in question. 3 or 4 post later you repost a superficial comparisson of repair times as "evidence" of disprotional damage resulting from poor design... -_-

I agree now would be a convenient point to end the discussion... before I spend hours typing quotes which suggest such things as:

- Tirpitz never being fully repaired hence 6 months is not a direct measure of the damage received
- A comparisson between the ships, equipment, and personel sent from Germany to assist repairing the Tirpitz vs. the trickle that the German Armistice commission allowed the french to send to repair Richelieu - not to mention a comparrison between getting said equipment from Germany to Norway vs France to Dakar
- The cumulative changes made to Tirpitz by 1943 as a result of 4 years war experience
- The capabilities of both ships in the hours and days immediately after the attacks


edit - err I misread that... for a while I thought you implying Dakar was a "very advanced repair facility."
Regardless it doesn't invalidate my argument that "6 months" now down considerably I see from your original "11" was spent to do alot more than just fix the Torpedo damage but also finish an INCOMPLETE FOREIGN SHIP.




@tommy ty for posting the Nevada document link

[Bgile]

I thought Tirpitz was never ready to deploy again. Still, the explosion under Tirpitz seem far larger than the one under Jean Bart so I don't think it's really relevant to a comparison of the two ships.

[alecsandros]

You originally posted repair time as evidence of poor design. When I posted evidence that qualified that repair time you dismissed it as being irrelavent to the scenario in question. 3 or 4 post later you repost a superficial comparisson of repair times as "evidence" of disprotional damage resulting from poor design... -_-

I have the distinct feeling I'm talking with somebody else. A bad day perhaps?

In my previous post, I wrote "6 months" of repairs because that is the lowest amount of time in which I know RIch underwent systematic repairs. I don't understand how you could have missed that...
And, if you're memory doesn't help to well, I'll say again: Rich underwent about 3 years of repairs and overhauls, in Dakar, USA and UK.

About the damage Tirpitz suffered:
-from G&D Axis BBs and Peillard's Sink the Tirpitz, I find numerous descriptions of structural damage similar to the one Richelieu suffered. Feel free to check.
- 6 months of repairs in Altafjord, without drydock, heavy cranes, etc, is qualitatively much, much less than the 6 months in the USA. Again, I can't think of any reason for which you fail to understand this.
- Tirpitz underwent repairs in Altafjord and conducted firing and speed trials in March-April 1944. Max speed was 27kts, because of deformations to the hull. The other capabilities of the ship remained the same.

It was only after operation Tungsten that the Germans decided to turn it into a floating battery...

What is much worse, though, is that you repeatedly use counter-factual arguments (explictly or implicitly) as if they would carry the same practical value as the factual statements.
Examples:
- you said JB could have been repaired in 3 months or less after bomb damage
- Richelieu could have suffered explosion refraction effects
- JB could have received a shell at 27km or beyond, which would explain the piercing of 150+40mm armored decks.

All of those are counter-factual examples, adressing to the world of possibilities. The world of documented reality on the other hand presents another perspective:
- JB's bomb damage was extensive and we can't know how much it would take to repair.
- Richelieu suffered a torpedo hit.
- From Morrison and G&D, the range of fire at Casablanca was between 18 and 24km.

I'm generaly an idea man; the realm of possibilities is interesting and challenging. However, between 2 arguments - 1 possible, 1 factual, I tend to accept the second one.

[alecsandros]

[...]the explosion under Tirpitz seem far larger than the one under Jean Bart so I don't think it's really relevant to a comparison of the two ships.

That's exactly the point at hand: Richelieu was damaged in a similar way (not exactly the same, but comparable nonetheless)

[neil hilton]

Regarding KGV versus Richelieu protection design. I believe the KGVs overall design was more advanced, she had thinner deck armour but it was placed higher in the hull (only one deck below the top) and concentrated as a single thickness instead of being spread into three pieces. This gives greater internal protection to vitals from plunging shellfire and bombs. The KGVs belt armor was thicker than Richelieu and homogenous but vertical, (Richelieus was sloped). I don't know any specifics about either classes internal compartmentalisation.
Another design advance in the KGVs was the incorporation of the bridge and citadel into one, sepperated designs result in C&C problems.
Concerning the comparison of 14" and 16" guns, many view it as a no brainer that bigger is better, I disagree. If the armour penetration is good enough to get inside the target the damage caused by either size of shell will be devastating.
It should also be noted that high muzzel velocites give greater range but what good is range if you can't hit anything. Historical fact is that the longest range hit of a moving target is about 27000yds (what good does it do to be able to shoot 45000yds). Also high muzzel velocites result in shells wobbling in flight, thus increasing dispersion.

Regarding underwater explosions causing greater damage, I believe this is because the explosion causes a vacuum under the vessel and the vessel then falls into it. Modern heavyweight torpedoes are designed to do this, which allows them to sink supercarriers.

[alecsandros]

It should also be noted that high muzzel velocites give greater range but what good is range if you can't hit anything.

French charges were also excessively "hot", making the blasts somewhat different from each others and propelling the shells at slightly different speeds from each other. Hence, excessive dispersion (someone said 600 yards at 25000k... for a full salvo)

[Bgile]

Another design advance in the KGVs was the incorporation of the bridge and citadel into one, sepperated designs result in C&C problems.

I don't know what you are talking about here. KGVs citadel wasn't associated with her bridge in any way. Edit: there was an armored tube going down to the citadel many decks below.

Concerning the comparison of 14" and 16" guns, many view it as a no brainer that bigger is better, I disagree. If the armour penetration is good enough to get inside the target the damage caused by either size of shell will be devastating.

Well that's the trick, isn't it? Fact is, 16" guns normally produce significantly better penetration than 14" guns, and so do 15" guns.

It should also be noted that high muzzel velocites give greater range but what good is range if you can't hit anything. Historical fact is that the longest range hit of a moving target is about 27000yds (what good does it do to be able to shoot 45000yds).

Higher velocity guns also penetrate more armor and have flatter trajectories and shorter flight times, resulting in more hits. Historical results doesn't mean longer range hits weren't possible. It just means lack of opportunity. We have a thread about that.

Also high muzzel velocites result in shells wobbling in flight, thus increasing dispersion.

As far as I know, that's simply not true. I think the German 28cm SK C/34 were about the highest velocity guns in use in WWII, and as far as I know they didn't have a "wobbling" problem. Do you have a reference showing excessive dispersion from these guns? Very high velocity does tend to wear out liners faster, but I'm not aware of inherent excessive dispersion due to high velocity.

Regarding underwater explosions causing greater damage, I believe this is because the explosion causes a vacuum under the vessel and the vessel then falls into it. Modern heavyweight torpedoes are designed to do this, which allows them to sink supercarriers.

Shells and torpedoes didn't normally explode under the hull in WWII, so not really relevant here. They did tend to pop rivets and cause shock damage, though.

Weren't you the person claiming very long range hits aren't possible because it didn't actually happen? How many super carriers have been sunk? Zero, so by your logic they must be unsinkable.

[tommy303]

Also high muzzel velocites result in shells wobbling in flight, thus increasing dispersion.

Wobble, or more properly yawing, of a projectile in flight is an almost inescapable reality of spin stabilized cylindro-conoidal projectiles; All have a little wobble or yaw in flight, but when it becomes a problem for accuracy it is usually a function of a mismatch between velocity, rate of spin, and shell configuration. If a projectile is under spun, so as not to be optimally stabilized, it may exhibit good accuracy at close ranges where its velocity is still relatively high, but poor accuracy and high dispersion at longer ranges where its velocity has degraded due to drag effects. Such a projectile will reach a point in its flight where its velocity and spin degrades and excessive yaw takes place and this increases drag. Add in variable wind effects and you may get a erratic behavior in range.

The opposite is overspinning a projectile for its configuration and veloicty. in such a case the projectile will not tend to nose over as it begins its descent, and its axis will remain alighed more or less with the horizontal. Again, this causes an increase in drag with a consequential loss in velocity and range.

[neil hilton]

Also high muzzel velocites result in shells wobbling in flight, thus increasing dispersion.

Wobble, or more properly yawing, of a projectile in flight is an almost inescapable reality of spin stabilized cylindro-conoidal projectiles; All have a little wobble or yaw in flight, but when it becomes a problem for accuracy it is usually a function of a mismatch between velocity, rate of spin, and shell configuration. If a projectile is under spun, so as not to be optimally stabilized, it may exhibit good accuracy at close ranges where its velocity is still relatively high, but poor accuracy and high dispersion at longer ranges where its velocity has degraded due to drag effects. Such a projectile will reach a point in its flight where its velocity and spin degrades and excessive yaw takes place and this increases drag. Add in variable wind effects and you may get a erratic behavior in range.

The opposite is overspinning a projectile for its configuration and veloicty. in such a case the projectile will not tend to nose over as it begins its descent, and its axis will remain alighed more or less with the horizontal. Again, this causes an increase in drag with a consequential loss in velocity and range.

This is exactly what I read about ballistics. Thanks for the full explanation.

I'm not claiming long range hits aren't possible, I don't believe 'lack of opportunity' can explain the real world fact that long range hits of moving targets are just incredibly rare, the bottom line is they are complete 'hail mary' attempts. There are many cases of ships opening up at very long ranges and not hitting anything until the distance closed significantly.

Incorporation of bridge and citadel in one doesn't necessarily mean close proximity but it may also mean quick and safe access between the two. I would be very surprised if they actually put them right next to each other where a single shell could wipe out both.

It was found out by the US submarine force in the Pacific during ww2, due to faulty torpedos with magnetic detonators running deeper than expected If I remeber right (completely accidentally) that the damage to the ship hit was excessive. In fact it invariably broke its back, further testing after the war confirmed this. Its not the size of the explosion really but the targets own weight and the stress it causes (from bow to midships to the stern) as the ship literally falls into the 'hole'.
Spearfish is designed to do this and the mk48 ADCAP. No supercarriers have been sunk but no ship is unsinkable, I don't see where I may have given you the impression I thought they were unsinkable but if I did it was a misunderstanding. Or am I misunderstanding your post?

[Bgile]

I'm not claiming long range hits aren't possible, I don't believe 'lack of opportunity' can explain the real world fact that long range hits of moving targets are just incredibly rare, the bottom line is they are complete 'hail mary' attempts. There are many cases of ships opening up at very long ranges and not hitting anything until the distance closed significantly.

It's just that there is another thread here involving a paper written by Bill Jurens and Brad Fischer in Warship International which demonstrates that long range hits are possible and likely under the right circumstances. There is no way I'm going to repeat it here.

Incorporation of bridge and citadel in one doesn't necessarily mean close proximity but it may also mean quick and safe access between the two. I would be very surprised if they actually put them right next to each other where a single shell could wipe out both.

Perhaps you don't understand what is commonly known as the Citadel in a Battleship. It's the enclosure of the ship's vitals in heavy armor. It includes heavy deck armor and a thick belt. The bridge area in the KGV class wasn't part of the citadel. It was many decks above it.

It was found out by the US submarine force in the Pacific during ww2, due to faulty torpedos with magnetic detonators running deeper than expected If I remeber right (completely accidentally) that the damage to the ship hit was excessive. In fact it invariably broke its back, further testing after the war confirmed this. Its not the size of the explosion really but the targets own weight and the stress it causes (from bow to midships to the stern) as the ship literally falls into the 'hole'.
Spearfish is designed to do this and the mk48 ADCAP. No supercarriers have been sunk but no ship is unsinkable, I don't see where I may have given you the impression I thought they were unsinkable but if I did it was a misunderstanding. Or am I misunderstanding your post?

Yes, you are misunderstanding.

First, US submarine torpedoes were DESIGNED to explode under the target. It wasn't an accidental discovery when the exploders failed. The exploders were defective and that feature was removed. Modern torpedoes do explode under the target and they work. What you said was that nearby shells caused extra damage because of that same principle, and that isn't true. They didn't explode under the ship. Bottom mines did, but usually much deeper and with somewhat less effect than a modern torpedo.

Let me see if I can explain may allusion to unsinkable carriers. First, you said long range gunnery isn't possible because it didn't happen. Then you said CVNs could be sunk by under hull torpedo explosions. The comparison I made is that if long range gunnery isn't possible because it didn't happen, then CVNs can't be sunk because that hasn't happened either. Just because something hasn't happened doesn't mean it isn't possible or practical. Late war battleships had radar which made long range gunnery possible, and in the case of US ships they practiced long range gunnery. They didn't ever find themselves in a position to use it, largely because the carrier had become a more effective weapon. This does not mean it wasn't possible. It wasn't possible in 1940, but that doesn't mean it wasn't possible in 1944.

[neil hilton]

Haven't read the thread about long range gunnery but from what you say it is similar to what I'm saying here, ie long range hits are possible under the right circumstances. And just how rare are those circumstances? Which thread is it BTW, maybe I can stick my oar in there too.

Of course the bridge and the citadel weren't physically close to each but they did have a quick and armoured passage between them, as has been stated. This is what I meant by 'combining into one' The accessibility between the 2 not the level of armour or the physical proximity.

US ww2 sub torps designed to explode under the hull, smart. I stand corrected.
If the exploders failed how would they know what the effect would be?

Don't remember saying anywhere shells would cause extra damage like a torpedo hit under the keel. Near hits do cause shock damage but not like a torpedo hit. Please point out where you got this impression so misunderstandings can be cleared up.

The CVN thing, misunderstanding cleared up. English can be quite an obscure language at times don't you think.

Again the long range gunnery thing. I really should read that other thread you pointed out.
Personnally I don't think any ww2 era gunnery system (including every step of the command chain, from radar to muzzle) is capable of even a reasonably accurate hit rate. Only in the 60s and 70s was this truly possible when weather radar and electronic computer design was sufficiently complex enough to achieve a decent hit rate. Of course this depends upon your definition of 'hit rate'.