# How would an Iowa-class battleship fare against this kind of beating? **URL:** \ **Category:** Factual Questions\ **Created:** [September 2, 2011, 3:10am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916 "2011-09-02T03:10:47Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [September 3, 2011, 4:31am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/41 "2011-09-03T04:31:04Z")
> [@Whack-a-Mole](#): > > IIRC this is how modern torpedoes work. > > They do not strike the ship directly. > > Rather, they swim under the ship and explode. This creates a “bubble” where there is no support for the ship’s weight. The ship’s “spine” (keel) cracks and it is done for. > > Not sure how a bomb exploding to the side of a ship would do this though. You need to be under the ship to make this happen. > > That is not to say such a bomb wouldn’t cause damage but sans a direct hit I doubt it’d do much to a battleship. They really were insanely tough ships. I had seen reports about torpedoes exploding under a ship and virtually breaking its back, and have not really thought about it to question it- until this thread. I can see that approach working with thin skinned merchant ships or even destroyers and corvettes. However, as pointed out battleships are designed to take a lot of punishment and their construction is all about strength. Also, would a torpedo (even with the concussion) be able to move a vessel weighing 30,000 tons sufficiently? If you consider the battleships sunk solely by torpedoes, they were all direct hits. From memory you had HMS Barham and Royal Oak. The Italian battleships disabled at Taranto were by direct torpedo hits. And in the Great War, the battleships that immediately come to mind as being sunk by torpedoes were again direct hits (Triumph, Majestic and Suffren). There are probably more that I haven’t recalled. Perhaps a torpedo expert can help me out here. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [September 3, 2011, 5:00am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/42 "2011-09-03T05:00:04Z")
> [@Cicero](#): > > I had seen reports about torpedoes exploding under a ship and virtually breaking its back, and have not really thought about it to question it- until this thread. > > I can see that approach working with thin skinned merchant ships or even destroyers and corvettes. > > However, as pointed out battleships are designed to take a lot of punishment and their construction is all about strength. Also, would a torpedo (even with the concussion) be able to move a vessel weighing 30,000 tons sufficiently? > > If you consider the battleships sunk solely by torpedoes, they were all direct hits. From memory you had HMS Barham and Royal Oak. The Italian battleships disabled at Taranto were by direct torpedo hits. And in the Great War, the battleships that immediately come to mind as being sunk by torpedoes were again direct hits (Triumph, Majestic and Suffren). There are probably more that I haven’t recalled. > > Perhaps a torpedo expert can help me out here. In WWII torpedoes were made to hit the ship. Modern torpedoes explode under a ship. The strength of a ship in WWII was not in the keel. ---
**Author:** ![mac\_bolan00](https://avatars.discourse-cdn.com/v4/letter/m/b3f665/32.png) [@mac\_bolan00](https://boards.straightdope.com/u/mac_bolan00)\ **Post date:** [September 3, 2011, 5:04am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/43 "2011-09-03T05:04:26Z")
IANA expert on that (and most things) but i know that old battleships take to torpedoes poorly. yamashiro, royal oak, barham, kongo (and the 4 exposed battleships at pearl.) but if you take the post-washington “fast” battleships, you’ll see that all of them can take one or two direct hits and keep fighting: bismark, north carolina, musashi, yamato. ---
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [September 3, 2011, 9:30am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/44 "2011-09-03T09:30:33Z")
Just for information, and perhaps a comparison point, at the Battle of Jutland the following ships sustained damage as listed: Seydlitz (German battle cruiser) 21 hits from heavy guns, 2 hits from secondary guns and struck by a torpedo. She survived although only just. Lutzow (German battlecruiser) 24 hits from heavy guns. Sunk. Derfflinger (German battlecruiser) 17 hits from heavy guns, 9 from secondary guns. Survived. Tiger (British battle cruiser) 17 hits from heavy guns, 4 from secondary guns. Survived. Lion (British battlecruiser) 12 hits from heavy guns. Survived. Warspite (British battleship) 13 hits from heavy guns. Survived. On the flip side the British battle cruisers Indefatigible, Invincible and Queen Mary each took only five heavy shells and blew up. ---
**Author:** ![AK84](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@AK84](https://boards.straightdope.com/u/AK84)\ **Post date:** [September 3, 2011, 11:47am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/45 "2011-09-03T11:47:22Z")
Well Jutland showed clearly that it mattered where you were hit. Queen Mary was hit half a dozen times by the Derfflinger each of which was in critical areas. ---
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [September 3, 2011, 12:01pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/46 "2011-09-03T12:01:20Z")
> [@AK84](#): > > Well Jutland showed clearly that it mattered where you were hit. Queen Mary was hit half a dozen times by the Derfflinger each of which was in critical areas. Not that it isimportant, but my reference shows she was being hit by both Seydlitz and Derfflinger- and she was hit by a couple of shells simultaneously. I guess the 1200 men who died didn’t really care who fired the fatal rounds. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [September 3, 2011, 12:43pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/47 "2011-09-03T12:43:30Z")
So could you build a “floating fortress” that sacrificed every other consideration for simply being so giga-armored that it was all but indestructible? Something with _ **meters** _ of armor all around? ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [September 3, 2011, 1:07pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/48 "2011-09-03T13:07:38Z")
> [@mac\_bolan00](#): > > IANA expert on that (and most things) but i know that old battleships take to torpedoes poorly. yamashiro, royal oak, barham, kongo (and the 4 exposed battleships at pearl.) but if you take the post-washington “fast” battleships, you’ll see that all of them can take one or two direct hits and keep fighting: bismark, north carolina, musashi, yamato. Yes, most WW1 battleships had very poor protection against underwater explosions, [HMS Audacious](http://en.wikipedia.org/wiki/HMS_Audacious_(1912)) was sunk by a single mine in 1914. Later WW1 designs were given [anti-torpedo bulges](http://en.wikipedia.org/wiki/Anti-torpedo_bulge), and between the wars they were retrofitted to many ships. The idea was to vent the force of the explosion outside the main structure of the ship, preventing or at least limiting flooding. This could be very effective, for example the 7,200 ton monitor [HMS Terror](http://en.wikipedia.org/wiki/HMS_Terror_(I03)) survived 3 torpedo hits without suffering any casualties. However, they were not sufficient to protect ships such as HMS Royal Oak or HMS Barham from the larger warheads used in WW2. Later treaty and post-treaty had internal TDS (torpedo defence systems), with various schemes of void spaces to vent explosions, crushing tubes, and oil and water filled compartments to dissipate the force, backed by an armoured bulkhead. Again, these provided limited protection against WW2 torpedoes. For example, the [USS North Carolina](http://en.wikipedia.org/wiki/USS_North_Carolina_(BB-55)) was hit by a single submarine launched torpedo. The blast overwhelmed the TDS, and actually reached the forward magazine. Fortunately, flooding prevented a fire from taking hold. Bear in mind, the TDS of the Iowas was no better than that of the North Carolinas. It was an enormous challenge for ship designers to adequately protect their ships. The TDS only covered about half of the length of the ship, the bow and stern were too thin to be protected. Most battleships were designed to stay afloat with both bow and stern flooded, but their speed would be severely reduced in that condition. The sheer size of these ships, coupled with water-tight internal bulkheads, provided some degree of protection. They could remain afloat with several compartments flooded. There is a good article about [TDS](http://www.navweaps.com/index_tech/tech-047.htm) here if anyone is interested. > [@mac\_bolan00](#): > > deck armor is just the start of it, literally. it also depends on how well and small and watertight one’s individual compartments are. firefighting capability is also critical. only a battleship shell can reliably penetrate a lightly armored deck and go clean to the bottom of the ship. The Yamato’s decks provided theoretical protection against 1,100 lb bombs, so would have been extremely difficult to sink with the 1,000 lb AP bombs used by the USN. However, if the need had been recognised, it would have been a simple matter of developing a heavier bomb. The [SB2C Helldiver](http://en.wikipedia.org/wiki/SB2C_Helldiver) in service was capable of carrying 2,000 lbs of ordnance. Other battleships did have their decks penetrated by bombs. As early as 1943, the [Roma](http://en.wikipedia.org/wiki/Italian_battleship_Roma_(1940)) was sunk by the [Fritz X](http://en.wikipedia.org/wiki/Fritz_X) guided bomb. One also blew out the bottom of HMS Warspite, crippling her. Post WW2, several nations had the technological capability of mating guidance systems with even larger warheads, capable of crippling a Yamato with a single hit. WW2 also saw the development of acoustic guided torpedoes. Such weapons confirmed the obsolescence of the battleship. > [@Whack-a-Mole](#): > > In WWII torpedoes were made to hit the ship. > > Modern torpedoes explode under a ship. Torpedoes designed to explode under the ship were used by the Royal Navy, Kriegsmarine and I think USN. However, the magnetic detonators were not particularly reliable. I’m not sure what such a weapon would do to a battleship. Certainly, it would cause serious flooding, as the bottom of the ship was not protected by a TDS. I wouldn’t rule out the possibility that it might break the ship in half. A battleship may be stronger than a smaller ship, but it is also very heavy and highly stressed. ---
**Author:** ![Zakalwe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zakalwe/32/270_2.png) [@Zakalwe](https://boards.straightdope.com/u/Zakalwe)\ **Post date:** [September 3, 2011, 1:09pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/49 "2011-09-03T13:09:42Z")
> [@Lumpy](#): > > So could you build a “floating fortress” that sacrificed every other consideration for simply being so giga-armored that it was all but indestructible? Something with _ **meters** _ of armor all around? Probably not. If you can see it, you can hit it. If you can hit it, you can kill it. The Germans had bunkers like that for the V2 program, the RAF (most famously 607 Squadron - flying the Avro Lancasters mentioned above) destroyed many of them. ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [September 3, 2011, 1:12pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/50 "2011-09-03T13:12:46Z")
This is a subject matter of which I know nothing, but since I do like to participate here are [Johnny Horton’s views on the Bismarck sinking](http://www.youtube.com/watch?v=KecIdlEAKhU). ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [September 3, 2011, 1:58pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/51 "2011-09-03T13:58:32Z")
> [@Lumpy](#): > > So could you build a “floating fortress” that sacrificed every other consideration for simply being so giga-armored that it was all but indestructible? Something with _ **meters** _ of armor all around? Not if you want it to a) float or b) work as an operational ship. Bouyancy is a function of the enclosed volume. Some battleships were more than 1/3 armour by weight. If you were to take one and add, say, 25% more armour, you would decrease it’s survivability. It would have a much lower reserve of bouyancy, so could be easily sunk by punching some holes in the unarmoured sections. You could compensate by removing some of the heavy quipement, such as guns, boilers and engines, but then you have a far less effective ship. Possibly something could be done with a very large thinkness of low-density armour. What is the density of kevlar? Bear in mind though, you need something strong and flexible enough not to break-up under wave action. ---
**Author:** ![AK84](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@AK84](https://boards.straightdope.com/u/AK84)\ **Post date:** [September 3, 2011, 2:37pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/52 "2011-09-03T14:37:58Z")
> [@Cicero](#): > > Not that it isimportant, but my reference shows she was being hit by both Seydlitz and Derfflinger- and she was hit by a couple of shells simultaneously. I guess the 1200 men who died didn’t really care who fired the fatal rounds. Yes there is a controvery, remember a mess up at the start of the action left _Derfflinger_ unengaged. I believe the latest view is that all the hits scored on her were by _Derfflinger_ including the fatal one, which IIRC was the second to last. Derfflinger fired 11 slavos at the Queen Mary, getting six hits, which is quite excellent shooting actually. ---
**Author:** ![Cicero](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cicero/32/3594_2.png) [@Cicero](https://boards.straightdope.com/u/Cicero)\ **Post date:** [September 3, 2011, 2:38pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/53 "2011-09-03T14:38:17Z")
And just for something totally off topic, I found that several pre dreadnoughts actually fought and survived not only WW1 but also WW2. ---
**Author:** ![AK84](https://avatars.discourse-cdn.com/v4/letter/a/85e7bf/32.png) [@AK84](https://boards.straightdope.com/u/AK84)\ **Post date:** [September 3, 2011, 6:35pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/54 "2011-09-03T18:35:33Z")
The first shots in Europe were fired by a German pre-Dreadnought, ---
**Author:** ![John\_DiFool](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_difool/32/19543_2.png) [@John\_DiFool](https://boards.straightdope.com/u/John_DiFool)\ **Post date:** [September 3, 2011, 9:05pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/55 "2011-09-03T21:05:38Z")
> [@Alka\_Seltzer](#): > > Not if you want it to a) float or b) work as an operational ship. Bouyancy is a function of the enclosed volume. Some battleships were more than 1/3 armour by weight. If you were to take one and add, say, 25% more armour, you would decrease it’s survivability. It would have a much lower reserve of bouyancy, so could be easily sunk by punching some holes in the unarmoured sections. You could compensate by removing some of the heavy quipement, such as guns, boilers and engines, but then you have a far less effective ship. I wonder what naval designers would do on a planet with higher gravity, where the tradeoffs would be even more extreme (at a guess-I know water is not very compressible but a ship would lay lower in the water at higher G’s). ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [September 3, 2011, 10:06pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/56 "2011-09-03T22:06:21Z")
> [@John\_DiFool](#): > > I wonder what naval designers would do on a planet with higher gravity, where the tradeoffs would be even more extreme (at a guess-I know water is not very compressible but a ship would lay lower in the water at higher G’s). I don’t think it would ride deeper. A ship floats because it has a lower average density than water, that ratio won’t change if you start messing with gravity. Hopefully someone can confirm or refute this, I don’t entirely trust my reasoning. > [@Cicero](#): > > And just for something totally off topic, I found that several pre dreadnoughts actually fought and survived not only WW1 but also WW2. Which ones survived? I thought the Greek pair were sunk, and the German ones scuttled. Mikasa (flagship at Tsushima) survived with bomb damage, but played no active role. Am I missing something? ---
**Author:** ![appleciders](https://avatars.discourse-cdn.com/v4/letter/a/85f322/32.png) [@appleciders](https://boards.straightdope.com/u/appleciders)\ **Post date:** [September 3, 2011, 10:41pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/57 "2011-09-03T22:41:18Z")
> [@Alka\_Seltzer](#): > > I don’t think it would ride deeper. A ship floats because it has a lower average density than water, that ratio won’t change if you start messing with gravity. Hopefully someone can confirm or refute this, I don’t entirely trust my reasoning. I agree with you on this one. It’s all about relative density, and the relative density of the water compared to the steel will be unchanged. Actually, because water is not totally incompressible, any compression of the water would tend to make the water denser and thereby cause the ship to float higher out of the water. To say whether an ocean experiencing, say, double Earth’s gravity would have water compressed enough to actually measure the difference is above my pay grade, though. ---
**Author:** ![user\_hostile](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/user_hostile/32/474_2.png) [@user\_hostile](https://boards.straightdope.com/u/user_hostile)\ **Post date:** [September 3, 2011, 11:06pm UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/58 "2011-09-03T23:06:13Z")
> [@appleciders](#): > > I agree with you on this one. It’s all about relative density, and the relative density of the water compared to the steel will be unchanged. Actually, because water is not totally incompressible, any compression of the water would tend to make the water denser and thereby cause the ship to float higher out of the water. To say whether an ocean experiencing, say, double Earth’s gravity would have water compressed enough to actually measure the difference is above my pay grade, though. Water is compressible but is insignificant for all intents and purposes of your example. Drop down to 4 km beneath the ocean, and you get a little under 2% by volume shrinkage. ---
**Author:** ![appleciders](https://avatars.discourse-cdn.com/v4/letter/a/85f322/32.png) [@appleciders](https://boards.straightdope.com/u/appleciders)\ **Post date:** [September 4, 2011, 1:15am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/59 "2011-09-04T01:15:07Z")
> [@user\_hostile](#): > > Water is compressible but is insignificant for all intents and purposes of your example. Drop down to 4 km beneath the ocean, and you get a little under 2% by volume shrinkage. Ah. Then there’d be no measurable difference, then. ---
**Author:** ![slowlearner](https://avatars.discourse-cdn.com/v4/letter/s/a88e57/32.png) [@slowlearner](https://boards.straightdope.com/u/slowlearner)\ **Post date:** [September 4, 2011, 2:53am UTC](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916/60 "2011-09-04T02:53:56Z")
i have read that, due to their size and damage control systems, it would take a nuclear warhead to sink a modern american aircraft carrier. possibly true? or sailors dreaming of mermaids? [Previous page](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916.md?page=2) [Next page](https://boards.straightdope.com/t/how-would-an-iowa-class-battleship-fare-against-this-kind-of-beating/594916.md?page=4)