Plunging fire was a concern, WW2 era ships were designed with stronger deck armour to address this. However, their protection against aerial bombs was still marginal. Yamato had thicker deck armour than the Iowas. Also, it had a greater reserve of bouyancy due to its larger size.
No, that wasn’t the reason the Hood was lost, she closed the range before being hit. It’s almost certain the belt was penetrated.
Really asking here because I do not know:
How is a bomb able to penetrate deck armor better than a plunging shot from a battleship’s main guns. Battleships flung 2000 pound projectiles designed to be armor piercing. Did planes in WWII carry 2000 pound bombs? Seems a bit heavy for the era unless you were a bomber (and not even sure they carried something that big).
A B-29 could. Little Boy and Fat Man both weighed in at roughly 5 tons each. But I’m unaware of any Superfortress being used in anti-ship operations. The Grand Slam bomb weighed in at 11 tons; it was dropped by Avro Lancasters. These are the only two that come to mind; there might be others
I am not surprised a bomber of that era could carry the weight but you have to admit those were unusual load outs. I thought most bombs back then were 500 pounds (or less).
IIRC high-level bombing of ships was dicey at best (as far as effectiveness goes).
Would make sense to fly high level bombers over ships out of range of their guns but landing a bomb on a ship in that era from that height was little better than a crap shoot. Hell, bombers were lucky to hit factories back then. A smaller (than a factory) moving/dodging target? Hitting it would be almost pure luck with an unguided bomb from bomber altitudes.
Because a bomb is hitting the deck at a nearly perpendicular angle, while even a long range shot is striking at a much shallower angle. This page has the gunnery tables for Bismarck. Even at 24,000 meters (about the world record for battleship gunnery) the shell’s angle of fall is only 22 degrees. According to the armour penetration curves at the bottom of the page, that’s not sufficient to penetrate 4 inches of armour.
Armour piercing bombs dropped by WW2 naval aircraft were generally between 500 and 1,000 lbs, but the japanese dropped some modified 16’ shells at Pearl Harbour, they would have been about 2,000 lbs. Sadly, one hit the Arizona.
I was just addressing the weight issue. Not the accuracy. After all, they were less concern about the A-bombs accuracy than conventional bombs.
Per the rest of your comment, no disagreement.
IIRC, I’m reminded of a picture (Life magazine or book?) I saw of a B-24 bomber that was returning from a mission in the Pacific Theater(?) and had a left over gravity bomb. They saw a Japanese controlled 2 lane bridge and dropped the bomb from 24,000 ft(?), and hit it dead on. It was a lucky shot on a static target–which would explain why it was published as a boy-this-doesn’t-happen-every-day!
Even a near-miss with a Grand Slam bomb, detonating in the water nearby, could break the back of an Iowa- or Yamato-class battlewagon, I would think.
After that post, I thought about that, but my WAG is that cracking the supersructure is a three stage process. 1) The boom which lifts the ship up, 2) the now unsupported center falling back down and cracking the center structure, and 3) the hammer effect from the water as the bubble collapses, breaking the ship in half. IOW, a near-miss from a Grand Slam would only partially accomplish this.
I leave it to others to nit-pick or otherwise destroy my insufferable logic.
16 FOOT shells! I want to see that gun! :eek:
(I know what you meant…couldn’t resist the nitpick though)
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.
To aid in penetrating battleship deck armor, the attack force at Pearl Harbor had dive bombers equipped with bombs that were modified from battleship armor-piercing shells. Dive bombers allow maximum accuracy with minimum time for the delivery vehicle within the AAA engagement envelope.
From this wiki chart of Japanese air dropped ordnance, it looks like the bombs were Type 99, Mk 80s, and thus ~800 kg, with around 30 kg of explosive filler, modified from 400mm naval artillery shells. The chart claims 150mm of armor penetration, which is nice, (and was certainly effective on the U.S.S. Arizona) but nowhere near the extent that a 400mm naval shell would penetrate in plunging fire. [Edit, and it looks like my Pearl Harbor point is already made. Need to type faster.]
It’s mentioned in the OP, but Iowa class BBs had by the middle of 1945, AAA emplacements that were probably a magnitude more effective than those of the Yamato, despite the latter’s giant (~160) number of manually operated 25mm AA guns. Yamato did not have radar guided 5in/38 DP guns like the Iowa. Nor did Yamato have proximity fuzes for its AAA. I am not familiar with the Iowa class’s record under massive air attack. I am slightly familiar with the closely related South Dakota BBs under air attack. During the battle of the Santa Cruz Islands in 1942, South Dakota alone accounted for 26 attacking planes during one day. Of course, the South Dakota was facing about a quarter of the airplanes that were attacking Yamato…
Finally, Japanese damage control was not noted for being a high priority in the IJN, nor was especially effective. Their most ignominuous failure being perhaps the loss of the CV Taiho from a single torpedo hit. Contrast that to the great emphasis placed on damage control by the U.S. Navy. U.S.S. Franklin is one amazing example; there are others from WW2.
I agree with the previous posters that if you throw multiple waves of 280 carrier aircraft at a WW2 surface combatant, said surface combatant is going to be sunk. I just want to state that I think the Iowa is going to take quite a few more planes down with it, and be combat effective for longer, despite having less armor than the Yamato.
Akin to what Elendil’s Heir wrote, 12,000 lb Tallboy bombs (the precursor to the 22,000 lb Grand Slam’s) were used in killing the German BB Tirpitz. The linked wiki for Tirpitz goes into much more detail about the effectiveness of Tallboy vs BB armor.
I too do not know the record of the Iowa’s but IIRC they were designed with AA defense in mind and were particularly good at it.
I would not want to be a pilot flying headlong into an Iowa AAA broadside.
ETA: I will also second the US focus on damage control. IIRC (again) when in battle carriers would flood their fuel lines with CO2 as well as having their crews extensively trained at damage control.
Sometimes it is the less obvious stuff that makes a difference (such as the US pulling experienced pilots to train new pilots where the Japanese left their best out in the field who, eventually, got killed. Even the best and brightest will get shot down if you roll the dice long enough).
I was responding to your assertion that the Iowas “traded armor for speed”, which wasn’t true-US designers basically were able to have their cake and eat it too thanks to several innovative approaches and new technologies. Again I agree that unless the deck armor was impractically thick, AP bombs were going to pierce any BB deck (tho the hardened steel that I mentioned had a chance to strip the AP cap from both AP bombs and shells, and the site I linked to showed that the Iowas’ deck armor wasn’t anything close to hopeless, like it was for Italy’s Vittorio Veneto class).
Not my first Spinal Tap moment, I often have trouble with my ’ and ".
Actually, the same 16" shells would not be able to penetrate six inches of deck armour in plunging fire, see my post above.
The proximity fuzes that became available late in the war made the 5" AA guns much more effective. One quote says they became seven times more effective against V1 flying bombs. However, it was still necessary to fire a lot of shells on average for each plane downed (unfortunately, I can’t find the exact figures). They could only thin out a mass attack, not stop one. Also bear in mind that the secondary turrets are only lightly armoured, and radar systems were very vulnerable to blast damage.
I’m dubious about the claim that South Dakota shot down 26 aircraft in one battle. In the chaos of combat, over-claiming was frequent, often 2 to 3 times actual losses.
True to an extent.
The Montana Class was a big version of the Iowas.
It did most everything better than an Iowa except for speed and I think a big part of the Iowa design principle was they were fast.
As with most things there is a tradeoff.
The Marianas Turkey Shoot would beg to differ.
The Japanese launched a massive air assault on US ships. By-and-large the Japanese pilots were slaughtered with negligible effect on US forces (not saying they had zero effect but considering the mass of planes they threw at it the effect was small).
Again, there are a variety of factors that play into that but my point is sheer weight of planes will not necessarily win you the day. The US had great AAA and fighters versus untrained Japanese pilots.
History tells the story better than I can.
How much did battleship AAA really contribute in that battle? My recollection is that most of the Japanese planes were shot down by American fighters, and only a handful ever made it anywhere near their targets.
I honestly do not know.
I recall seeing newsreel footage of the battle and it was ships shooting at planes so some clearly made it to the fleet.
How many? I have no clue.
As noted above it was the biggest carrier battle even and the Japanese lost ~600 planes (and several carriers as well). Lots and lots of planes in the air from both sides.
Naval battle to end all naval battles seems like.
They were mostly shot down by the CAP, there are details in the wiki article. The remainder were broken up into small groups, and were only able to carry out piecemeal attacks.
Land based planes, about 35 out of 50 shot down by CAP.
First wave of carrier planes, the CAP accounted for 41 out of 68. The survivors attacked several different targets.
Second wave of 107, about 70 shot down by the CAP, and another 25 or so by AA fire.
Third wave of 47, 7 shot down by CAP, but most of the survivors didn’t attack any ships, so 40 planes made it back.
The remainder of the planes destroyed were on the carriers that were sunk.
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. as mentioned above, the yamato and musashi lost nearly all its AA weapons to dive bombers but both were from from being sunk at that point.