By: a89
- 22nd July 2016 at 09:42Permalink- Edited 1st January 1970 at 01:00
The four British ships fired more than 2,800 shells at Bismarck, and scored more than 400 hits, but were unable to sink Bismarck by gunfire."
Which makes sense. Bismarck displaced almost 50,000 tons, that's a lot of volume/space. Most of the hits took place above waterline. When attacking other battleships like Yamato torpedoes only targeted one side to cause capsizing.
By: mrmalaya
- 22nd July 2016 at 11:25Permalink- Edited 1st January 1970 at 01:00
Two Fritz X sunk the Roma......you don't need close to half a dozen of the biggest baddest Cold War AShMs to either send the Bismark to the bottom, or to render her a worthless hulk.
Two (admitedly very large) bombs caused the Tirpitz to flip right over.
See second post (with an upgrade to the weapon involved to take account of bigger target).
By: FBW
- 22nd July 2016 at 19:39Permalink- Edited 1st January 1970 at 01:00
Iowa's armor was not spectacular. Just look at its size, displacement, installed machinery weight...expecting magic is silly.
Littorio's decapping scheme probably gave it more effective armor. Iowa had a weaker belt than KGV. Richelieu had somewhat better protection than South Dakota, and Iowa had the same scheme as SoDak (with same deficient torpedo protection) just on a much larger hull....
Iowas had the same scheme as the S Dakota class, true. The last two Iowas had thicker belt and turret face armor. Most experts concur the S. Dakota and Iowa had the most effective armor schemes for their displacements. The mix of class A and B armor at a 19* angle with 1.5" of STS to decap AP shells. It was not the thickest, not the best at close range, and the overall scheme had some weaknesses: US designers planned for engagements at long range. The Iowas and S. Dakotas were very well protected from plunging fire. The scheme showed it's weakness to a degree at Guadalcanal, the S. Dakota's unarmored upper works were shot up leaving the ship unable to fight (but seaworthiness was unaffected). Richelieu's face hardened armor had a tendency to shatter rather than give. A 2,700lb 16 inch shell passed through both armored decks of the Jean Bart and blew up in an empty magazine at Casablanca.
Bismark was stronger in myth than reality, vertical belt, poor protection from plunging fire. It was a dated scheme, but had very high quality armor and a lot of it.
By: Yama
- 22nd July 2016 at 23:20Permalink- Edited 1st January 1970 at 01:00
Iowas had the same scheme as the S Dakota class, true. The last two Iowas had thicker belt and turret face armor. Most experts concur the S. Dakota and Iowa had the most effective armor schemes for their displacements. The mix of class A and B armor at a 19* angle with 1.5" of STS to decap AP shells.
Outer armour was not intended for decapping AP shells and probably would have been quite ineffective in it.
Only Littorio-class had outer armour designed for decapping, it was 70mm, ie. twice the thickness in Iowas. This Italians had calculated as minimum necessary to decap 15" shells.
However the space between outer and inner belt was quite small, and it might have been too small to allow effective decapping.
Inclined belt had its disadvantages: it was heavier, often required outer plating to maintain hull profile and encouraged shells to ricochet downwards, under the ship.
HMS Hood had 12" inclined belt, just like Iowas...
I once did some thoughtwork about shooting anti-ship missiles at a battleship. Your typical ASM has roughly same explosive power as WW2 torpedoes, which often did bad things to battleships even when they hit the armour belt, so it would be far from guaranteed that the missiles would bounce off from armour. A complication is that missile warheads are designed against unarmoured target ships, delayed warhead hitting thick armour might disintegrate before detonation, thus reducing explosive power.
A large, supersonic ASM has many times kinetic energy of a 16 inch shell and would probably just smash the armour in. Against a diving missile attack, it would be much much worse. A supersonic diving missile like Kh-22 would easily penetrate the deck armour, ignite the magazines and blow the ship up.
But even assuming that missiles can't penetrate armour, and all belt, barbette and turret armour is invulnerable to anti-ship missiles: so what? Take a look at this diagram about Iowa's armour scheme:
Grey line is the waterline. Note how something like 80% of the ship over waterline is unarmoured or protected by just very thin armour. Say you fire 8 Exocets at a battleship, two would strike armour and be ineffective, that leaves six missiles hitting unarmoured parts of the ship. Many of the comms and radars and fire control systems would be probably knocked out, signifantly reducing ships combat capability. Worse, they would start major fires. We know from experience that one Exocet hit is generally mission kill to 4000-5000 ton ship. Six missiles would likely be more than enough to make sure that any ship is hors de combat, even if she doesn't actually sink.
By: Amazingchickens
- 23rd July 2016 at 01:17Permalink- Edited 1st January 1970 at 01:00
"The four British ships fired more than 2,800 shells at Bismarck, and scored more than 400 hits, but were unable to sink Bismarck by gunfire."
-towards the end of trying to sink bismarck
This is because of Bismark's inefficient and antiquated turtle back armour scheme, which protected it's Citadel from effectively point blanc (<3km) fire from Rodney and KGV (it's also worth mentioning that the vast majority of these hits were not from 14 and 16 in guns).
This of course didn't matter at all, because everything above the waterline was on fire and/or in many separate pieces (like the forward turrets and their crew), which brings me onto my point; Battleships are hard to sink, however, they are surprisingly easy to render combat ineffective (heck, many had a reputation for destroying their own targeting radars).
I reckon a Kh-22 hit would be enough to send any battleship back to drydock.
By: RadDisconnect
- 23rd July 2016 at 04:17Permalink- Edited 1st January 1970 at 01:00
You can't shoot if you can't see, and all the armor in the world is useless if your fire controls and radars remain vulnerable. You lose those, then you're just a big punching bag with no relevance in combat. Now, some degree of protection is necessary to ensure that you don't lose your crew and what not in a single hit, but going back to battleship level protection is silly. Which is why modern warships are more about having smaller ships that spread out your fire power and focus on not getting hit in the first place.
Iowa's armor was not spectacular. Just look at its size, displacement, installed machinery weight...expecting magic is silly.
Littorio's decapping scheme probably gave it more effective armor. Iowa had a weaker belt than KGV. Richelieu had somewhat better protection than South Dakota, and Iowa had the same scheme as SoDak (with same deficient torpedo protection) just on a much larger hull....
Iowa's outer plate isn't for decapping, though it and another layer of high tensile steel plating still adds somewhat to the effective armor thickness, and the inclination also complicates penetration, especially at longer ranges with steeper plunging angle. Richelieu's belt is similar to the Iowa and South Dakota though without the additional high tensile steel plating and thinner outer plating. It has exceptional deck protection too. I realized I left out the KGV earlier, and the side protection of these ships are arguably second only to the Yamato (possibly more due to quality of British steel, considered best in the world), with subsequent Lion and Vanguard having thinner belts (still external and fully vertical). There's also isolating magazines and thickness of armor between magazine and other compartments, which the Iowa and KGV do a better job of than others. The use of armored belt on the South Dakota, Iowa, and especially Yamato (due to greater thickness of said belt below the waterline) does modestly downgrade explosive proof rating, though liquid loading certain voids help mitigate that. That being said, the same belt armor under the waterline allow these three ships to have the best resistance to underwater shell hits, though those aren't particularly common. Nathan Okun provides a good analysis of battleship armor, focusing on the Bismarck but also giving insights on KGV, South Dakota, Richelieu, Vittorio, and Yamato. Some of the decapping information is outdated but much of it still holds.
I know fellow American posters think fondly of the Iowa, but in pure protection terms she's nothing special. She's well protected and comparable to her contemporaries, but that's that, and there's nothing remarkable about it.
Anyways, all this is academic and not relevant to today's combat. Being armored doesn't mean anything if you end up getting mission killed in the first place. South Dakota's electrical failure in the naval battle of Guadalcanal shows that.
By: FBW
- 23rd July 2016 at 05:02Permalink- Edited 1st January 1970 at 01:00
Outer armour was not intended for decapping AP shells and probably would have been quite ineffective in it.
Only Littorio-class had outer armour designed for decapping, it was 70mm, ie. twice the thickness in Iowas. This Italians had calculated as minimum necessary to decap 15" shells.
However the space between outer and inner belt was quite small, and it might have been too small to allow effective decapping.
All armor is not equal for one. The 1.5 inch STS was deemed sufficient to decap an AP shell or redirect it to a less optimal penetration angle. This was tested, not opinion.
nclined belt had its disadvantages: it was heavier, often required outer plating to maintain hull profile and encouraged shells to ricochet downwards, under the ship.
HMS Hood had 12" inclined belt, just like Iowas...
The Hood's belt was different armor, narrow and tapering below waterline. Totally different armor scheme that was inferior to plunging fire. The RN knew this at the outset of WWII, events meant that the Hood's armor was not modified. What happened?
A large, supersonic ASM has many times kinetic energy of a 16 inch shell and would probably just smash the armour in. Against a diving missile attack, it would be much much worse. A supersonic diving missile like Kh-22 would easily penetrate the deck armour, ignite the magazines and blow the ship up.
Not sure what you are smoking here.... The 2,700lb 16" shell fired from the 16" 50 caliber had a velocity of 2,500 fps (2,743 km/h), at 40,000 yards still moving at 1755 km/h. No contest in kinetic energy, compare the Oniks with a mark 8 shell, it's like comparing a sabot round to a HESH round in a tank.
By: RadDisconnect
- 23rd July 2016 at 05:09Permalink- Edited 1st January 1970 at 01:00
All armor is not equal for one. The 1.5 inch STS was deemed sufficient to decap an AP shell or redirect it to a less optimal penetration angle. This was tested, not opinion.
No, that was based on the old emperical formula by Nathan Okun that is no longer valid. Here is his updated analysis, and based on email I've had with him it takes over 2 inch of STS to decap a 15 inch AP shell. The current 1.5 inch STS will only decap if strike angle is greater than 15 degrees.
The Hood's belt was different armor, narrow and tapering below waterline. Totally different armor scheme that was inferior to plunging fire. The RN knew this at the outset of WWII, events meant that the Hood's armor was not modified. What happened?
Iowa's armor also tapers below the waterline, so I'm not sure what point you're making here. The Hood is essentially an upscaled version of the Queen Elizabeth battleships, and in any case it's the thin deck armor of the Hood that was it's undoing.
Not sure what you are smoking here.... The 2,700lb 16" shell fired from the 16" 50 caliber had a velocity of 2,500 fps (2,743 km/h). No contest in kinetic energy.
That's the muzzle velocity. Actual striking velocity on deck will be much lower since the projectile is plunging.
A modern supersonic AShM will mission kill any WW2 battleship, if not outright wreck it.
By: FBW
- 23rd July 2016 at 05:26Permalink- Edited 1st January 1970 at 01:00
No, that was based on the old emperical formula by Nathan Okun that is no longer valid. Here is his updated analysis, and based on email I've had with him it takes over 2 inch of STS to decap a 15 inch AP shell. The current 1.5 inch STS will only decap if strike angle is greater than 15 degrees.
No, I've read his as well. 15* angle would be a fairly short range engagement (depending on muzzle velocity, ex. around 17,000 yards for the 15" mark I), as I said, that was where the armor scheme of the Iowa's was inferior. (Bismark V. PoW and Hood started at around 24,000 yards, Hood was killed around 14,000 yards). Other engagements in WWII: USS Massachussets V Jean Bart ~24,000 yards, HMS Duke of York V. Scharhorst 12,000 yards , Rodney V Bismark 20,000 yards initially, Second naval battle of Guadalcanal was the outlier due to it being a nighttime engagement- 8000 yards, yet the only direct 14" hit on the S. Dakota (barbette) did not penetrate.
Even prior to radar directed fire, the battle of Jutland saw the fleets engage each other roughly 15,000-13,000 yards apart.
Iowa's armor also tapers below the waterline, so I'm not sure what point you're making here. The Hood is essentially an upscaled version of the Queen Elizabeth battleships, and in any case it's the thin deck armor of the Hood that was it's undoing.
If you have any of the old Jane's fighting ships you will see the point. The 12" belt was narrow, with 7" below and above and tapering to 5" and 4" fore and aft. There was a gap between belt and deck armor of the Hood as well. The shell that killed the Hood still had to go through the upper 7" or 5" belt into the magazine.
That's the muzzle velocity. Actual striking velocity on deck will be much lower since the projectile is plunging.
Already addressed that, was still writing when you posted this.
A modern supersonic AShM will mission kill any WW2 battleship, if not outright wreck it.
Already addressed this, no if you are considering a measurement of armor penetration, not even close. If you are considering a hit on the superstructure, sure a modern AShM would cause massive damage. Much larger warhead than a shell or AP bomb. During the Gulf War, the USN was not as worried about the Iowa's taking a hit from a silkworm as they were from mines for good reason.
By: RadDisconnect
- 23rd July 2016 at 06:20Permalink- Edited 1st January 1970 at 01:00
The Oniks is a 6000 lbs missile using a 550 lbs warhead with Mach 2.5 speed, so close to 2700 km/h. And that's the speed it strikes too, so in terms of kinetic energy, especially at close range when it had more fuel onboard, it vastly outdo the Mark 8 shell from a 16 inch gun. It may not have the hardened tip but it's sheet kinetic energy will do the job.
By: FBW
- 23rd July 2016 at 06:28Permalink- Edited 1st January 1970 at 01:00
The Oniks is a 6000 lbs missile using a 550 lbs warhead with Mach 2.5 speed, so close to 2700 km/h. And that's the speed it strikes too, so in terms of kinetic energy, especially at close range when it had more fuel onboard, it vastly outdo the Mark 8 shell from a 16 inch gun. It may not have the hardened tip but it's sheet kinetic energy will do the job.
Ok, compare the size of the two, composition (density). Then consider that the Oniks is not going to be a 3 ton missile at the target nor is it's speed 3062 km/h at sea level (closer to 2400 km/h, mach 2 at sea level). Velocity is not everything, hardened cap of small diameter vs seeker head on missile. Which one would you say is designed to penetrate? The AP shell was designed for a specific purpose, to penetrate armor plate, the same is not true of modern AShM, they don't have to.
By: Yama
- 23rd July 2016 at 09:39Permalink- Edited 1st January 1970 at 01:00
Ok, compare the size of the two, composition (density). Then consider that the Oniks is not going to be a 3 ton missile at the target nor is it's speed 3062 km/h at sea level (closer to 2400 km/h, mach 2 at sea level). Velocity is not everything, hardened cap of small diameter vs seeker head on missile. Which one would you say is designed to penetrate? The AP shell was designed for a specific purpose, to penetrate armor plate, the same is not true of modern AShM, they don't have to.
AP shells were designed that way because of technological limitations, not because it was ne plus ultra in defeating armour plate. If they could have built a 16 inch shell with one-ton explosive charge, they would.
Kh-22 missile (AS-4, you know, what Backfires carry) strikes with speed of Mach 3 or so, weights ~6 tons at launch and has one ton HE warhead. That is over 30 times explosive power of 16 inch AP shell.
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By: Scar
- 23rd July 2016 at 11:11Permalink- Edited 1st January 1970 at 01:00
Velocity is not everything, hardened cap of small diameter vs seeker head on missile. Which one would you say is designed to penetrate?
In ASM, the role of penetrator plays not seeker, but a hardened warhead/penetrator behind it. Like that one i posted on the previous page.
By: Andraxxus
- 23rd July 2016 at 13:24Permalink- Edited 1st January 1970 at 01:00
Ok, compare the size of the two, composition (density). Then consider that the Oniks is not going to be a 3 ton missile at the target nor is it's speed 3062 km/h at sea level (closer to 2400 km/h, mach 2 at sea level). Velocity is not everything, hardened cap of small diameter vs seeker head on missile. Which one would you say is designed to penetrate? The AP shell was designed for a specific purpose, to penetrate armor plate, the same is not true of modern AShM, they don't have to.
Valid points but I don't think you are fully aware of the magnitude of kinetic energy an AShM have. Lets compare from another point of view;
Second Anti-ship missile (probably of P-500 type) hits the ship from the bow, penetrates hull and every bulkhead and walls ship has and exits from the stern. Ship is probably (judging from the size comparison with P-500) slightly over 80 meters long. If we look at the path missile follows within the ship there is way greater mass of steel than a 40-50 cm armor would have. Worse, its arranged like a "spaced armor", so it has much greater effectiveness than a single bulk of metal.
Can an 16/18 inch AP shell penetrate an unarmored 80 meter long ship in similar fashion the missile in the video?
Second Anti-ship missile (probably of P-500 type) hits the ship from the bow, penetrates hull and every bulkhead and walls ship has and exits from the stern. Ship is probably (judging from the size comparison with P-500) slightly over 80 meters long. If we look at the path missile follows within the ship there is way greater mass of steel than a 40-50 cm armor would have. Worse, its arranged like a "spaced armor", so it has much greater effectiveness than a single bulk of metal.
Can an 16/18 inch AP shell penetrate an unarmored 80 meter long ship in similar fashion the missile in the video?
Yes, impressive. Obviously a shell would not be able to replicate that trajectory. There are many instances of a large AP shell passing through both sides of a destroyer sized ships with ease and not exploding.
I don't know, I could be wrong but the answer seems obvious to me. A 2,700lb projectile with a hardened steel tip moving at 1,743 km/h striking an area of a few square inches Vs. a several ton missile (most of which is soft- fuel, electronics, engine) moving at 2,400 km/h hitting an area of several square feet. The missile is going to break apart dissipating some of the energy. Most AShM are going to explode after breaking into the ships hull and kill by explosive force sending molten jet of metal, unburnt fuel through the ship, very effective for today's warships which might have a few inches of kevlar around vitals. But penetrating 1.5" of STS then 11.5" of class A armor at a 19* angle?
We are not talking about explosive force, for those commenting before. As I've said, there is no contest there a missile like the Oniks carries the explosives of several shells. A hit would blow a massive hole in the side for sure, and a hit on the upper structure would do catastrophic damage without question. What I am not so sure about it a AShM being able to penetrate the armor belt. I still feel the comparison I made on the previous page to be accurate. Comparing the two is like comparing a sabot round of a tank to a HESH round. Both may disable the tank, only one is penetrating the armor plate.
Edit- put a 2 instead of a one in for the AP shell velocity
By: Andraxxus
- 23rd July 2016 at 17:20Permalink- Edited 1st January 1970 at 01:00
True, but AP round is not exactly a APFSDS round; granted a steel tip will perform better in the first milliseconds of the entry, but an 16 inch round still has to make a hole roughly 16 inches in diameter in order to get past the armor. Its length to diameter ratio is pathetic, actually less than 1/3 of a Anti-ship missile, so it would be much more prone to ricochet instead of going inside the armor.
A P-500 missile is 22 inches in diameter, so roughly it has 1,9 times area that would be focusing several times greater kinetic energy and even greater explosive force to that area.
Of course, a P-500 missile can fly on preprogrammed autopilot and can recieve course updates and made to impact from more favourable angles or be made to top dive, but IMHO that still wouldn't be necessary.
By: Duggy
- 23rd July 2016 at 17:45Permalink- Edited 1st January 1970 at 01:00
94th Fighter Squadron F-22A Raptor pilots drop joint direct attack munitions
during the 95th anniversary of William "Billy" Mitchell bombing the
Ostfriesland at Langley Air Force Base, Va., July 21, 2016. Mitchell and the
1st Provisional Air Brigade demonstrated to the world the superiority of air
power by sinking the famous unsinkable, Ostfriesland, a captured German
battleship. (U.S. Air Force photo by Staff Sgt. J.D. Strong II)
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By: a89 - 22nd July 2016 at 09:42 Permalink - Edited 1st January 1970 at 01:00
Which makes sense. Bismarck displaced almost 50,000 tons, that's a lot of volume/space. Most of the hits took place above waterline. When attacking other battleships like Yamato torpedoes only targeted one side to cause capsizing.
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By: mrmalaya - 22nd July 2016 at 11:25 Permalink - Edited 1st January 1970 at 01:00
See second post (with an upgrade to the weapon involved to take account of bigger target).
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By: haavarla - 22nd July 2016 at 12:34 Permalink - Edited 1st January 1970 at 01:00
The Krupp Steel used on Bismarck was a class on its own.
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By: FalconDude - 22nd July 2016 at 19:23 Permalink - Edited 1st January 1970 at 01:00
I thought that was answered conclusively in WW2.
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By: FBW - 22nd July 2016 at 19:39 Permalink - Edited 1st January 1970 at 01:00
Iowas had the same scheme as the S Dakota class, true. The last two Iowas had thicker belt and turret face armor. Most experts concur the S. Dakota and Iowa had the most effective armor schemes for their displacements. The mix of class A and B armor at a 19* angle with 1.5" of STS to decap AP shells. It was not the thickest, not the best at close range, and the overall scheme had some weaknesses: US designers planned for engagements at long range. The Iowas and S. Dakotas were very well protected from plunging fire. The scheme showed it's weakness to a degree at Guadalcanal, the S. Dakota's unarmored upper works were shot up leaving the ship unable to fight (but seaworthiness was unaffected). Richelieu's face hardened armor had a tendency to shatter rather than give. A 2,700lb 16 inch shell passed through both armored decks of the Jean Bart and blew up in an empty magazine at Casablanca.
Bismark was stronger in myth than reality, vertical belt, poor protection from plunging fire. It was a dated scheme, but had very high quality armor and a lot of it.
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By: Yama - 22nd July 2016 at 23:20 Permalink - Edited 1st January 1970 at 01:00
Outer armour was not intended for decapping AP shells and probably would have been quite ineffective in it.
Only Littorio-class had outer armour designed for decapping, it was 70mm, ie. twice the thickness in Iowas. This Italians had calculated as minimum necessary to decap 15" shells.
However the space between outer and inner belt was quite small, and it might have been too small to allow effective decapping.
Inclined belt had its disadvantages: it was heavier, often required outer plating to maintain hull profile and encouraged shells to ricochet downwards, under the ship.
HMS Hood had 12" inclined belt, just like Iowas...
I once did some thoughtwork about shooting anti-ship missiles at a battleship. Your typical ASM has roughly same explosive power as WW2 torpedoes, which often did bad things to battleships even when they hit the armour belt, so it would be far from guaranteed that the missiles would bounce off from armour. A complication is that missile warheads are designed against unarmoured target ships, delayed warhead hitting thick armour might disintegrate before detonation, thus reducing explosive power.
A large, supersonic ASM has many times kinetic energy of a 16 inch shell and would probably just smash the armour in. Against a diving missile attack, it would be much much worse. A supersonic diving missile like Kh-22 would easily penetrate the deck armour, ignite the magazines and blow the ship up.
But even assuming that missiles can't penetrate armour, and all belt, barbette and turret armour is invulnerable to anti-ship missiles: so what? Take a look at this diagram about Iowa's armour scheme:
Grey line is the waterline. Note how something like 80% of the ship over waterline is unarmoured or protected by just very thin armour. Say you fire 8 Exocets at a battleship, two would strike armour and be ineffective, that leaves six missiles hitting unarmoured parts of the ship. Many of the comms and radars and fire control systems would be probably knocked out, signifantly reducing ships combat capability. Worse, they would start major fires. We know from experience that one Exocet hit is generally mission kill to 4000-5000 ton ship. Six missiles would likely be more than enough to make sure that any ship is hors de combat, even if she doesn't actually sink.
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By: Amazingchickens - 23rd July 2016 at 01:17 Permalink - Edited 1st January 1970 at 01:00
This is because of Bismark's inefficient and antiquated turtle back armour scheme, which protected it's Citadel from effectively point blanc (<3km) fire from Rodney and KGV (it's also worth mentioning that the vast majority of these hits were not from 14 and 16 in guns).
This of course didn't matter at all, because everything above the waterline was on fire and/or in many separate pieces (like the forward turrets and their crew), which brings me onto my point; Battleships are hard to sink, however, they are surprisingly easy to render combat ineffective (heck, many had a reputation for destroying their own targeting radars).
I reckon a Kh-22 hit would be enough to send any battleship back to drydock.
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By: RadDisconnect - 23rd July 2016 at 04:17 Permalink - Edited 1st January 1970 at 01:00
You can't shoot if you can't see, and all the armor in the world is useless if your fire controls and radars remain vulnerable. You lose those, then you're just a big punching bag with no relevance in combat. Now, some degree of protection is necessary to ensure that you don't lose your crew and what not in a single hit, but going back to battleship level protection is silly. Which is why modern warships are more about having smaller ships that spread out your fire power and focus on not getting hit in the first place.
Iowa's outer plate isn't for decapping, though it and another layer of high tensile steel plating still adds somewhat to the effective armor thickness, and the inclination also complicates penetration, especially at longer ranges with steeper plunging angle. Richelieu's belt is similar to the Iowa and South Dakota though without the additional high tensile steel plating and thinner outer plating. It has exceptional deck protection too. I realized I left out the KGV earlier, and the side protection of these ships are arguably second only to the Yamato (possibly more due to quality of British steel, considered best in the world), with subsequent Lion and Vanguard having thinner belts (still external and fully vertical). There's also isolating magazines and thickness of armor between magazine and other compartments, which the Iowa and KGV do a better job of than others. The use of armored belt on the South Dakota, Iowa, and especially Yamato (due to greater thickness of said belt below the waterline) does modestly downgrade explosive proof rating, though liquid loading certain voids help mitigate that. That being said, the same belt armor under the waterline allow these three ships to have the best resistance to underwater shell hits, though those aren't particularly common. Nathan Okun provides a good analysis of battleship armor, focusing on the Bismarck but also giving insights on KGV, South Dakota, Richelieu, Vittorio, and Yamato. Some of the decapping information is outdated but much of it still holds.
I know fellow American posters think fondly of the Iowa, but in pure protection terms she's nothing special. She's well protected and comparable to her contemporaries, but that's that, and there's nothing remarkable about it.
Anyways, all this is academic and not relevant to today's combat. Being armored doesn't mean anything if you end up getting mission killed in the first place. South Dakota's electrical failure in the naval battle of Guadalcanal shows that.
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By: FBW - 23rd July 2016 at 05:02 Permalink - Edited 1st January 1970 at 01:00
All armor is not equal for one. The 1.5 inch STS was deemed sufficient to decap an AP shell or redirect it to a less optimal penetration angle. This was tested, not opinion.
The Hood's belt was different armor, narrow and tapering below waterline. Totally different armor scheme that was inferior to plunging fire. The RN knew this at the outset of WWII, events meant that the Hood's armor was not modified. What happened?
Not sure what you are smoking here.... The 2,700lb 16" shell fired from the 16" 50 caliber had a velocity of 2,500 fps (2,743 km/h), at 40,000 yards still moving at 1755 km/h. No contest in kinetic energy, compare the Oniks with a mark 8 shell, it's like comparing a sabot round to a HESH round in a tank.
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By: RadDisconnect - 23rd July 2016 at 05:09 Permalink - Edited 1st January 1970 at 01:00
No, that was based on the old emperical formula by Nathan Okun that is no longer valid. Here is his updated analysis, and based on email I've had with him it takes over 2 inch of STS to decap a 15 inch AP shell. The current 1.5 inch STS will only decap if strike angle is greater than 15 degrees.
Iowa's armor also tapers below the waterline, so I'm not sure what point you're making here. The Hood is essentially an upscaled version of the Queen Elizabeth battleships, and in any case it's the thin deck armor of the Hood that was it's undoing.
That's the muzzle velocity. Actual striking velocity on deck will be much lower since the projectile is plunging.
A modern supersonic AShM will mission kill any WW2 battleship, if not outright wreck it.
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By: FBW - 23rd July 2016 at 05:26 Permalink - Edited 1st January 1970 at 01:00
No, I've read his as well. 15* angle would be a fairly short range engagement (depending on muzzle velocity, ex. around 17,000 yards for the 15" mark I), as I said, that was where the armor scheme of the Iowa's was inferior. (Bismark V. PoW and Hood started at around 24,000 yards, Hood was killed around 14,000 yards). Other engagements in WWII: USS Massachussets V Jean Bart ~24,000 yards, HMS Duke of York V. Scharhorst 12,000 yards , Rodney V Bismark 20,000 yards initially, Second naval battle of Guadalcanal was the outlier due to it being a nighttime engagement- 8000 yards, yet the only direct 14" hit on the S. Dakota (barbette) did not penetrate.
Even prior to radar directed fire, the battle of Jutland saw the fleets engage each other roughly 15,000-13,000 yards apart.
If you have any of the old Jane's fighting ships you will see the point. The 12" belt was narrow, with 7" below and above and tapering to 5" and 4" fore and aft. There was a gap between belt and deck armor of the Hood as well. The shell that killed the Hood still had to go through the upper 7" or 5" belt into the magazine. Already addressed that, was still writing when you posted this. Already addressed this, no if you are considering a measurement of armor penetration, not even close. If you are considering a hit on the superstructure, sure a modern AShM would cause massive damage. Much larger warhead than a shell or AP bomb. During the Gulf War, the USN was not as worried about the Iowa's taking a hit from a silkworm as they were from mines for good reason.
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By: RadDisconnect - 23rd July 2016 at 06:20 Permalink - Edited 1st January 1970 at 01:00
The Oniks is a 6000 lbs missile using a 550 lbs warhead with Mach 2.5 speed, so close to 2700 km/h. And that's the speed it strikes too, so in terms of kinetic energy, especially at close range when it had more fuel onboard, it vastly outdo the Mark 8 shell from a 16 inch gun. It may not have the hardened tip but it's sheet kinetic energy will do the job.
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By: FBW - 23rd July 2016 at 06:28 Permalink - Edited 1st January 1970 at 01:00
Ok, compare the size of the two, composition (density). Then consider that the Oniks is not going to be a 3 ton missile at the target nor is it's speed 3062 km/h at sea level (closer to 2400 km/h, mach 2 at sea level). Velocity is not everything, hardened cap of small diameter vs seeker head on missile. Which one would you say is designed to penetrate? The AP shell was designed for a specific purpose, to penetrate armor plate, the same is not true of modern AShM, they don't have to.
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By: Yama - 23rd July 2016 at 09:39 Permalink - Edited 1st January 1970 at 01:00
AP shells were designed that way because of technological limitations, not because it was ne plus ultra in defeating armour plate. If they could have built a 16 inch shell with one-ton explosive charge, they would.
Kh-22 missile (AS-4, you know, what Backfires carry) strikes with speed of Mach 3 or so, weights ~6 tons at launch and has one ton HE warhead. That is over 30 times explosive power of 16 inch AP shell.
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By: Scar - 23rd July 2016 at 11:11 Permalink - Edited 1st January 1970 at 01:00
In ASM, the role of penetrator plays not seeker, but a hardened warhead/penetrator behind it. Like that one i posted on the previous page.
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By: Andraxxus - 23rd July 2016 at 13:24 Permalink - Edited 1st January 1970 at 01:00
Valid points but I don't think you are fully aware of the magnitude of kinetic energy an AShM have. Lets compare from another point of view;
https://youtu.be/BvigKyp_hcs?t=1m17s
Second Anti-ship missile (probably of P-500 type) hits the ship from the bow, penetrates hull and every bulkhead and walls ship has and exits from the stern. Ship is probably (judging from the size comparison with P-500) slightly over 80 meters long. If we look at the path missile follows within the ship there is way greater mass of steel than a 40-50 cm armor would have. Worse, its arranged like a "spaced armor", so it has much greater effectiveness than a single bulk of metal.
Can an 16/18 inch AP shell penetrate an unarmored 80 meter long ship in similar fashion the missile in the video?
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By: Yama - 23rd July 2016 at 14:09 Permalink - Edited 1st January 1970 at 01:00
The target ship in the video is a 4000 ton accommodation ship, 111 metres long. About a size of a frigate.
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By: FBW - 23rd July 2016 at 14:23 Permalink - Edited 1st January 1970 at 01:00
Yes, impressive. Obviously a shell would not be able to replicate that trajectory. There are many instances of a large AP shell passing through both sides of a destroyer sized ships with ease and not exploding.
I don't know, I could be wrong but the answer seems obvious to me. A 2,700lb projectile with a hardened steel tip moving at 1,743 km/h striking an area of a few square inches Vs. a several ton missile (most of which is soft- fuel, electronics, engine) moving at 2,400 km/h hitting an area of several square feet. The missile is going to break apart dissipating some of the energy. Most AShM are going to explode after breaking into the ships hull and kill by explosive force sending molten jet of metal, unburnt fuel through the ship, very effective for today's warships which might have a few inches of kevlar around vitals. But penetrating 1.5" of STS then 11.5" of class A armor at a 19* angle?
We are not talking about explosive force, for those commenting before. As I've said, there is no contest there a missile like the Oniks carries the explosives of several shells. A hit would blow a massive hole in the side for sure, and a hit on the upper structure would do catastrophic damage without question. What I am not so sure about it a AShM being able to penetrate the armor belt. I still feel the comparison I made on the previous page to be accurate. Comparing the two is like comparing a sabot round of a tank to a HESH round. Both may disable the tank, only one is penetrating the armor plate.
Edit- put a 2 instead of a one in for the AP shell velocity
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By: Andraxxus - 23rd July 2016 at 17:20 Permalink - Edited 1st January 1970 at 01:00
True, but AP round is not exactly a APFSDS round; granted a steel tip will perform better in the first milliseconds of the entry, but an 16 inch round still has to make a hole roughly 16 inches in diameter in order to get past the armor. Its length to diameter ratio is pathetic, actually less than 1/3 of a Anti-ship missile, so it would be much more prone to ricochet instead of going inside the armor.
A P-500 missile is 22 inches in diameter, so roughly it has 1,9 times area that would be focusing several times greater kinetic energy and even greater explosive force to that area.
Of course, a P-500 missile can fly on preprogrammed autopilot and can recieve course updates and made to impact from more favourable angles or be made to top dive, but IMHO that still wouldn't be necessary.
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By: Duggy - 23rd July 2016 at 17:45 Permalink - Edited 1st January 1970 at 01:00
94th Fighter Squadron F-22A Raptor pilots drop joint direct attack munitions
during the 95th anniversary of William "Billy" Mitchell bombing the
Ostfriesland at Langley Air Force Base, Va., July 21, 2016. Mitchell and the
1st Provisional Air Brigade demonstrated to the world the superiority of air
power by sinking the famous unsinkable, Ostfriesland, a captured German
battleship. (U.S. Air Force photo by Staff Sgt. J.D. Strong II)