psl_58

German gunnery relied on stereoscopic range finding which is indeed much harder to use , but then German research showed that a small percentage of the population had much better stereoscopic vision than the masses. These select few were channeled into gunnery positions.

Pretty sure Bismarck's communication's were all under MAD. Bismarck superior hull armor was designed to get the ship home no matter how much shell pounding it took. This was achieved at the expense of traditional combat protection [ Front turret ; Barbette & CT etc], based on the assumption that fighting outnumbered, these would eventually be destroyed anyway. All German warships were designed to be able to "runaway from what they could not defeat'', but that calculation was always based on not engaging superior enemy. Hood & PoW were superior to Bis & Pe, so Lutjens should have reverse course and made dash to the Artic seas. With various Dithmarschen tankers they could out wait the Home Fleet and try again in a week or so....otherwise scrub the mission. Germans had not raided in the summer months before because the weather is good enough for enemy air power to patrol the GIUK giving them best chance to detect any break out attempt.

Thanks Thoddyx! From D&G they can add that the third attack was with 9 Beauforts and the Scharnhorst was making 24knots after severe torpedo damage in the bow. So we have 3 attacks with 6 + 5 + 9+ ? bombers that was replied with 905 4" flak plus 1256 x 37mm & 2385 x 20mm flak. This hail of fire resulted in 4 Swordfish & 2 Beauforts shot down and all attacks driven off. On average each shot down plane required ~ 700-800 shells . A better figure could be extrapolated if we assume only the 20mm fire as short range on the first two attacks, since G&D report the Beaufort attack was driven off by combined 105 & 37mm fire. Also we can assume the 4th attack was purely long range 105 flak fire. Broadly speaking we can build a model of attacks based on groups of fire. four 226 x 105 shells three 419 x 37 shells two 1192 x 20mm shells First & second short range attacks each 2 shot down with 226 x 105 shells+419 x 37 shells + 1192 x 20mm shells; 593 short range shells & 322 med-long range shells per shoot down Third medium range attack had 2 shot down with 226 x 105 shells+419 x 37 shells . 322 shells per shoot down. Fourth long range attack had zero shot down 226 x 105 shells expended. no results. Its a start but we need about 10-20 more such reports to build any effectiveness profile like the Americans did with the flak fire in Pacific wars.

Splitting hairs ; since there is a chance that both ships could have been sunk that day.

Battle cruisers were designed from the start to counter German overseas raiders that could badly disrupt commonwealth trade during war time. Long endurance and enough speed to chase down a protected cruiser was what was needed tactically. As this evolved during the 1920s 30s the threats to Battle cruiser didn't materialise .German surface raiders were able to outfight British cruisers but were not designed to out run RN Battle Cruisers. . With the development of the Twins from the Panzerschiffe D requirement - this changed with the lines being blurred. Were the Twins to out run RN/French Battle cruisers or defeat them in battle or both? They could do neither! As the British modernised their aging fleet they could not help but notice there was not as much of a need for > 30knots top speed but more protection was needed against emerging surface raider gun threats. So armor was increased at the expense of top speed. Hitler helped by fumbling the German naval rearmament since he was more interested in continental warfare than naval warfare. All he wanted from KM was a coastal defense fleet with limited surface fleet to dominate the Baltic and North Sea.

Yes true but originally all these ships DEFG etc were planned as 18,500 ton surface raiders. When Hitler took power KM went mad and inflated all their ship plans as far as they could push them....that's how a 18-20kt Panzerschiffe nearly doubles in size over a span of a couple of years. Dunkerque battle cruiser was merely a transitory excuse to get it by Hitler. Anti French he could tolerate, but anti British he would not tolerate.

AEGIS was super expensive and would never have been mounted on anything other than the new cruisers/Destroyers at that time. BPDM was designed to be a cheap retrofitted to older smaller warships to establish an elementary SAM capability . This would be especially valuable to Iowa class since the Phalanx had already been installed and resent wars had the BB doing coastal bombardment which would bring them into harms way. I would have gotten rid of all the 5" mounts and installed another pair of BPDM systems...

No you just reduce the production waste and redirect the resources to higher priority weapons systems. You end up with same tonnage of warships constructed , just higher priority items. For example do you need 2 x 38,000 ton Panzerschiffe & 2 x 50,500 ton BB, when original plan called for 6 x 18,500 ton ? That's 67000 tons warship construction wasted of which 67,000 tons was armored steel. The 6 Panzerschiffe were unlikely to need much more than 4000 tons each saving 43,000 tons for other naval or army construction. Did they need to build 1/2 dozen specialised fast tankers built to warship standards at cost of 120,000 tons new construction, when there were nearly a dozen fast [16knot ] tankers in the merchant fleet already that would be commandeered in war time? Do you waste 18-19,000 ton on each of 5 heavy cruisers with decidedly short range ,when you don't have a long endurance fast Panzerschiffe and instead have to rely on BC to fill that role? Did they need 3500 ton destroyers when 1500 ton Gross Torpedoboot was originally planned for? That's another 25,000 tons wasted. Do you pursuit a high risk -high cost propulsion system in the 'hopes' that it will be efficient enough within a few years to fill all the speed and endurance required for a whole new generation of warships? Diesel had already shown it could handle the endurance with the "PBS" and the "Bremes", so instead build on that lead. The Grille already showed that it would take 2-3 times as much bunker fuel for a turbine system to have the same endurance as the all Diesel Bremes. Hybrid Diesel Turbine systems had been explored since before WW-1 and seemed like a promising route forward.

The relative values are probably acceptable, but you can't strictly go on X result or Y result since the testing conditions may be completely different. Most military tests were done for political reasons and are not real objective tests. BTW decapping of shells is merely a part of the results from any given projectile plate impact but probably the most visible.

As a rule of thumb all ballistics tests done "pre 1960s" are of little value in the study of ballistics- since the methodology is flawed; so such tests are only of passing interest. http://www.navweaps.com/index_inro/INRO_Hood_p4.htm The study I read was quoted by Bill Jurens in 1987 article that appeared in Warship International #2. The ratings on the armor plates are 50lb weather deck 30lb second deck and 50+30 lbs on main deck. That's about 4" on the main engine spaces while the magazine was much thicker. http://navypedia.org/ships/uk/brit_bb1_hood.htm This site reports over Mags 76mm + 51mm + 38mm ...160mm. The Engine spaces look like 51mm+ 25mm + 19mm or 95mm.

We let Germany off the hook far too much when it comes to the rearmament phase and Hitler. Germany could have build a much larger naval fleet than was historically built, given the existing historical resources etc. Plain fact is Hitler didn't want a large fleet since it could cut into his West Wall fortification amongst other things. . More important he gambled that the British would give him a free hand in Europe in exchange for non aggression towards the Empire . After all the worse thing that could happen is if Britain is defeated but all her colonial power is grabbed by other enemy countries. Given enough time [late 1940s] he would deal with Britain. And its on this premise that Raeder also gambled Hitler was right and he had more than a decade to rebuild the KM. However in the wake of Hitler's 4 year plan in1936, it was only the LW that saw the inevitability of war by 1940 and made some effort to prepare for the inevitable.

HOOD s deck protection was more than sufficient to prevent any plunging fire from getting to the vitals. The top deck was 2" over the magazine while the main armor deck was 3" plus there was other decks in between with armor. One study put the deck protection of HMS HOOD at 160mm to 250mm depending on the size of shell descending In the plunging fire.

what plunging fire?

Even if the rudder was hit, had it been hit straight in line with the hull Bismarck would have raced home at 20 knots only to periodically adjust to aim for France. It would not have been stuck going around in circles.

Do not over exaggerate any weapons systems , its always going to be humans that fight each other not technology.

The HOOD was hyped but so was the Bismarck PW, as much by the British as the Germans. Likewise survivor stories conflict. Some German survivor's insist the ship was scuttled rather than sunk by the British, while other insist an order was issued but may not have had time to carry out before sinking. To believe one and ignore the others is to do disservice to all of their memories....we just don't know for sure.

Yes if the fuse worked properly which it did not. No telling what it might have done. Tell you what....why don`t you go back and reread post 69. It was the opinion of the Admiralty , not my opinion.

Actually the theory is that since Hoods belts were so short -2.85m vs Bismarck's 5.2m tall belts- the shell may have passed underneath the main belt. As I said a similar thing happened to the PoW in the same fight with a shell making its way into the bottom deck near the keel. It was a dud and failed to explode , otherwise they would have lost two BB that day.

What ever hits occurred on HMS Hood the Bismarck only hit once during its 5th salvo. An earlier hit was obtained by the Cruiser Prince Eugen that did start a fire, but that's been ruled out as the cause of the catastrophic explosion. There is speculation in a new book [Hood vs Bismarck] that the 5th Salvo actually resulted in two of Bismarck's 15" shells striking the ship simultaneously ...but still struggling through this since is mostly statistic maths etc.

the evidence doesn't support the shell through the deck hypothesis, which is more or less been rejected, The best explanation is the shell making it through the lower hull into the MAG. POW was similarly hit with another of Bismarcks 15" shells , and the shell ended up near the keel but was a dud. Admiralty concluded after they cut a hole in the bottom hull and removed that shell, they would have lost 2 BB that day had this shell detonated too.

Bismarck's main belt was 5 meters tall while Hoods was <3m, which meant more of the underwater hull was exposed. More importantly Bismarck's main belt was backed up by 4.3" slopes at sharp angle plus 1.8" Torpedo Bulk head. To get through to the vitals an 15" shell would have to penetrate something like 25" armor. HMS Hood also had slopes of 2" but these were at poor angle and would be perpendicular to any shell penetrating the main belt. Combined maybe 16-18" resistance. http://navypedia.org/ships/germany/ger_bb_bismarck.htm http://navypedia.org/ships/uk/brit_bb1_hood.htm One of the main theories of the HOODs destruction is a shell passing underneath the main belt and triggering one of the magazine bunkers.

For a Rail gun to be accurate it must use sensors to aim, sensors that must be accurate at considerable range. These sensors can easily be jammed & spoofed more so than the missile can - since the missile is always getting closer to the target, so jamming is less effective. Once a missile is programmed to track a target it needs no further input from the launching system and pretty much any warship can carry them. This makes them really cheap from a fleet POV. Rail guns need massive power systems and electrical power to work. Only specific large warships can employ them which is very expensive from a fleet POV. The reason the USN is wasting its money on Rail guns is because it can and few else can. They are hoping its the next best thing in naval warfare. Finally warships are increasing compartmentalised so any small holes in the warships will not comprise the over all warship. Hit the ship with a big fast missile or Torpedo that explodes and its going to break in two and sink.

No offense intended but this is only a 3d [3 projectile diameter] penetration into a semi infinite target which is pretty low. in fact the crater generated is much wider than it is deep , which suggests a soft metal target....block aluminum?. In destroying warships penetration is only important if there is armor to be penetrated. if there is no armor there is no need for penetration. In fact if you have to much penetration the shell may pass completely through the target leaving only localised damage in its wake. More to the point to start massive fire inside the target after you've blow a section of the hull out and compromised the longitudinal strength of the structure. A missile can do this.

Thanks Maou. This gets back to a grip I have about such analysis that it misses the basic set up of one against many. At least in DS battle it was 2V2 or more likely 2v1.5 if you consider the PE to be 1/2 an "effective unit". But the Bismarck was only able to manage about 10-12 knots which should make the Bismarck an easier target to hit than the British ships?

Which is why the Bismarck's shooting was so poor? If the British firing was so effected they still registered order of magnitude more hits during the initial clash than the Bismarck achieved. Or was this another example of AGS gunner being poor because of command interference?