Naval History Forums

The less powerful naval version of the 105 mm gun (with a limited AA capability) used on smaller warships fired a shell having the same weight (15.1 kg) but a smaller burster (3.8 kg as opposed to 5.2 kg in the AA round).

Thanks for this very interesting information. I was beginning to doubt whether the figures were correct. In German sources, the Marine-Arsenal issue on Bismarck by Breyer gives the same burster values for 37 mm, 88 mm and 105 mm as Whitley. Paul Smalenbach in his history of German naval fire control...

This question of the high bursters in some German shells has also puzzled me for a long time. For example, Whitley in his books on German battleships and cruisers, gives the burster of the 88 mm as 3.1 kg and that for the 105 mm as 5.2 kg. These amount to about one third of the shell weight. I've al...

Thanks DunMunro for this very clear plan. The class B belt extends a little above the 3rd deck. This is similar to the arrangement of the TB in most German designs and probably offers the best support for deflection under the explosive loading of an underwater detonation. The support of the lower ed...

The points BGile made could also be made in respect of the Hood. Tennyson was the expert and had various reasons for the distribution of armor he chose. Jellicoe was not a designer. Nevertheless, he thought in late 1916 that the sudden drop from 12 in to 7 in very bad and preferred a 7 ft 10 in wide...

Delcyros makes the point that the SD/Iowas had an vulnerable strip corresponding to shells hitting at or a little below the waterline and going on to strike the top of the class B lower belt. This is exactly the point I made a couple of weeks ago, and the diagram (of Iowa) is the one from the marin...

DunMunro wrote: "... the auxiliary boiler room was flooded" Brennecke says that the Backboard (port) Kesselhilfsmaschinnenraum (in compartment XII) was flooded. This contained an auxiliary condenser and a Havarie Schaltraum (flooding control I think). The other space in question was the Hi...

Dave Saxton/DunMunro wrote " ... and the auxiliary boiler room" : I have just been rereading the most comprehensive German account on this action I know of in the book by Brennecke. It says that the turbogenerator room (compartment XIV), port No. 2 boiler room (compartment XIII) and the p...

Good point Dave. Indeed, there is no mention of damage above the generator room, a space still below the panzer deck. Given that the Iowa's lower belt thinned to something similar to the TB in the Bismarck, it seems reasonable to suppose that damage would have been similar, viz very significant dama...

There are blueprints of the Iowas at http://www.ussmissouri.org For a hull depth of 52 ft 11.875 in, the 3rd deck was about 32 ft 4 in above the outer bottom and the second deck about 42 ft 6 in. The top of the main belt was about 6 ft in from the side. This must have resulted in a saving of deck ar...

The initial investigation of the hit by Bismarck on POW found the shell went through the outer plating 28 ft under water at an angle of fall of about 2 deg with little yaw. However, Offord, the RN ballistics expert said at the 2nd Hood enquiry that it had been found after dissection of the shell tha...

To me, it is obvious that the Iowa had better underwater protection than most other battleships apart from the larger Yamato. However, it appeared to have a narrow zone of vulnerability just below the main belt. This is shown in those German and American calculations done on that marine-archive site...

Just to point out that there has been a discussion in the Vittorio Veneto section that has a bearing on the Iowa/Bismarck discussion. If you look up http://forum-marinearchiv.de and then go to the discussion "Bismarck/Scharnhorst: why not inclined belts?''' (it is in German) and look at pp. 16 ...

Thank you, Thorsten. I've now read through that German site to the end (btw, does 'Aufrichtung' mean yaw?). I agree that the Bismarck has the best protection in the 10000 and 15000 m situations considered in these calculations. VV is second best. This is also the view of experts as diverse as Dave S...

I thought members would be interested in a German forum I have found: http://forum-marinearchiv.de If you look up a piece entitled "Side armor Bismarck/Scharnhorst, why not sloped?" (it is all in German) you will find on pages 16 and 17, detailed comparisons of most Second War battleships ...