Search found 882 matches

by Bill Jurens
Wed May 28, 2008 11:51 pm
Forum: Bismarck General Discussion
Topic: 2,000 tons of seawater in Bismarck's forecastle!
Replies: 52
Views: 16484

Re: 2,000 tons of seawater in Bismarck's forecastle!

The projectile probably did not explode, or if it did explode, it exploded low-order. It did cut through a transverse bulkhead, however. The passage of the shell, whether it exploded or not, did not involve any fuel tanks directly; these were two decks below. The forward fuel tanks were almost certa...
by Bill Jurens
Fri May 23, 2008 4:13 pm
Forum: Naval Weapons
Topic: AP shells and sea water
Replies: 22
Views: 41860

Re: AP shells and sea water

I do not have enough information at hand to do more than speculate regarding the background of Japanese projectile design. I did not mention consequences at all, which is another topic. One of the characteristics of underwater trajectories is that they are really quite unpredictable unless angle of ...
by Bill Jurens
Thu May 22, 2008 3:34 am
Forum: Naval Weapons
Topic: AP shells and sea water
Replies: 22
Views: 41860

Re: AP shells and sea water

Glad to help if I can. The underwater ballistics of spinning projectiles tends to be highly unpredictable. Very few tests were completed, and in those tests which were completed, the results were often problematical. Prior to the advent of modern technologies, about the only way to track a projectil...
by Bill Jurens
Tue May 20, 2008 1:36 am
Forum: Naval Technology
Topic: Armor Thickness – lbs and Inches
Replies: 15
Views: 49739

Re: Armor Thickness – lbs and Inches

It should be. A 40# plate is a 40# plate, regardless of the country where it happens to be manufactured. Basically, a 40# plate weighs 40 pounds per square foot. All things being equal, it would typically be about 0.98 inches thick.

Bill Jurens
by Bill Jurens
Mon May 19, 2008 6:22 pm
Forum: Naval Technology
Topic: Armor Thickness – lbs and Inches
Replies: 15
Views: 49739

Re: Armor Thickness – lbs and Inches

There was no special British inch, etc. associated with armor thicknesses. Everybody's inch was exactly the same, at least to six or seven decimal places. The confusion arises from the 'rough' conversion of 40# being equal to 1" thickness. This was a 'rough and ready' conversion, similar to the...
by Bill Jurens
Mon Apr 21, 2008 2:58 am
Forum: Bismarck General Discussion
Topic: 2,000 tons of seawater in Bismarck's forecastle!
Replies: 52
Views: 16484

Re: 2,000 tons of seawater in Bismarck's forecastle!

Yes. I think your diagram is correct. I did not compute the volume marked in blue up to the deckhead, only to the 9.6 meter waterline.

Bill Jurens
by Bill Jurens
Mon Apr 21, 2008 2:54 am
Forum: Ship Models, Plans and Drawings
Topic: Faired Line Drawings
Replies: 2
Views: 3523

Re: Faired Line Drawings

Although the Bundesarchiv in Germany still holds a high-quality faired lines plan for Bismarck, at scale 1:100, I do not think they still have numerical offsets. My recollection is at a full offset book was captured by the Allies after the war, but has subsequently been lost or misfiled. In most cas...
by Bill Jurens
Sun Apr 20, 2008 11:45 pm
Forum: Bismarck General Discussion
Topic: Fuel again, compartment XIV.
Replies: 1
Views: 1338

Re: Fuel again, compartment XIV.

Compartment XIV is about 9 meters long, and the cross sectional area of the fuel tank in this area averages about 15.66 3m^2, giving a total fuel volume of about 141 m^3. Assuming the volume permiability to be about 0.95, and the density of the fuel oil to be about 0.89, this gives us an initial fue...
by Bill Jurens
Sun Apr 20, 2008 3:55 pm
Forum: Bismarck General Discussion
Topic: 2,000 tons of seawater in Bismarck's forecastle!
Replies: 52
Views: 16484

Re: 2,000 tons of seawater in Bismarck's forecastle!

The volume given is taken from a curve of sectional areas, derived from the lines plan. In this case, it includes all of the volume between the base line and the nominal design waterline, which I have set for computational purposes to be 9.6 meters. The figures were adapted from my unpublished paper...
by Bill Jurens
Sun Apr 20, 2008 5:47 am
Forum: Bismarck General Discussion
Topic: 2,000 tons of seawater in Bismarck's forecastle!
Replies: 52
Views: 16484

Re: 2,000 tons of seawater in Bismarck's forecastle!

No. The quotes in question -- and the name of this thread -- seems to specify that the flooding related only to the forecastle areas, so that is the only calculation I discussed, or provided.

Bill Jurens
by Bill Jurens
Sat Apr 19, 2008 4:07 pm
Forum: Bismarck General Discussion
Topic: 2,000 tons of seawater in Bismarck's forecastle!
Replies: 52
Views: 16484

Re: 2,000 tons of seawater in Bismarck's forecastle!

By pure coincidence, I recently did a great deal of computational work on Bismarck's hydrostatics whilst completing an unrelated project. I can share some of that now. The flooding on Bismarck from this forward hit apparently extended from Frame 203 to Frame 224. Although flooding may not have been ...
by Bill Jurens
Fri Apr 11, 2008 2:59 am
Forum: Bismarck General Discussion
Topic: Bismarck construction flaws
Replies: 397
Views: 284245

Re: Bismarck construction flaws

Yes, I would draw it somewhat differently today. There is very good imagery of the entire exterior of the conning tower. The two 'dents' in the forward starboard quadrant should stay, but I might want to remove or revise the through cracks showing aft. There is no evidence available to justify any r...
by Bill Jurens
Thu Apr 10, 2008 9:35 pm
Forum: Bismarck General Discussion
Topic: Bismarck construction flaws
Replies: 397
Views: 284245

Re: Hits to Conning Tower, drawing, and South Dakota hit

I have only now read the recent correspondence on this thread. There were some questions as to whether or not Bismarck's conning tower was penetrated. Close examination of videotapes and photographs taken (literally) from two or three feet away, on three separate occasions, tells me that it was not....
by Bill Jurens
Tue Feb 26, 2008 4:05 pm
Forum: Bismarck General Discussion
Topic: Up High Gun Directors
Replies: 15
Views: 3679

Evidence

I have inserted 'answers' after asterisks inside RF's questions from the previous memo: RF wrote: Bill, The available circumstantial evidence suggests that something happened to degrade Hood's gunnery control after Hood's third salvo narrowly missed the PE. *** Well, perhaps. What we have is eye-wit...
by Bill Jurens
Sat Feb 23, 2008 1:30 am
Forum: Bismarck General Discussion
Topic: Up High Gun Directors
Replies: 15
Views: 3679

Hit on Hood

Either Briggs' account is incorrect, or it has been mis-read. The Board of Inquiry was very specific in asking when falling bodies were observed. This took place after the main explosion. Could a hit which did not detonate go unobserved? Certainly, but it is likely that even a non-exploding hit woul...