KMS Aeneas

[Carthaginian]

Still... halfway to the bottom of the water you're sailing on is dangerous.
There's a reason that towboats on US rivers still take 'by the mark, twain' so seriously.
I've seldom seen a man so embarrassed as a towboat pilot who had to stop the next TWO towboats behind him to help him get his tow off a submerged sandbar.

[Valles]

The Maori Cross Mirage has an average design draft of ten meters flat...

But she's also native to the Pacific, rather than the North Sea, which means she has different constraints.

[damocles]

I think the BC and L/B are both too low for a ship this size and speed.

Dimension ratios of the USS South Dakota

688/108=6.37B/L

Draft=11.36 meters. or 35 feet.

Beam x length x draught within 10% of the SD. BC is the big question.

D.

[Guinness]

Because I was curious about it:

Bismarck in her July 1940 inclining with 400t of inclining weights: 8.92m (mean). Without: 8.85m (mean)

Hood in 1940: 10.1m (deep draft), 8.9m (light condition). These values were 9.7m and 8.6m respectively on commissioning. I don't have at hand what here original design draft was before she gained all the post-Jutland weight though.

For American ships, the controlling parameter was the sill of drydock #4 at the New York Naval Shipyard (aka the Brooklyn Navy Yard). Unfortunatley, I don't remember what that value is, but it's in Friedman's BB book. I want to say that it was 40 feet. At any rate, all the US BB's have real drafts from inclining experiments in Friedman, so I can look them up later, but I seem to remember something on the order of 11m +/- for all of the post-treaty BBs. IIRC Colorado was the deepest of all the US BBs, with a loaded draft of 12m.

So something more than 9m draft doesn't seem to out of the question.

For block coefficients: I've done some research here already:
http://www.navalism.org/index.php?topic=727.msg44539#msg44539

As I have for L/B ratios:
http://www.navalism.org/index.php?topic=727.msg30396#msg30396

[damocles]

I was aware of the draught issues and I am aware that beam is also an issue, bot what worried me was BC.

I can argue the L&W issues historically. What worried me was the BC.  This I took from the Alaska example. This is like a Dutch frigate. So I treated this ship like one.

D.

[Guinness]

I'll look up Alaska later too, but I suspect that like many of the BCs and other stats in Springsharp's included examples, it's wrong.

[damocles]

I'll look up Alaska later too, but I suspect that like many of the BCs and other stats in Springsharp's included examples, it's wrong.

I'd like to know that info. I don't have Freedman.

[TexanCowboy]

This ship is not comparable to Alaska....Alaska was 4 knots faster, had 12'' guns in triples, and was from 20 years later. This ship is 4 knots slower, has 16'' guns in quads, and was from the 20s. This ship is much more comparable to HMS Hood.

[Jefgte]

IMO, Not tiptop hull BB

- Increase the BC & then reduce the draught to 10m or 10.2 max.
- Increase slightly the beam too.
- Increase the bulkhead to the draught value.
- Increase torp protection, 5.3 is short for nearly 34000t BB.

You note "1916", so, tech references to Jean-Bart or North Carolina are not realist.


Jef

[damocles]

IMO, Not tiptop hull BB

- Increase the BC & then reduce the draught to 10m or 10.2 max.
- Increase slightly the beam too.
- Increase the bulkhead to the draught value.
- Increase torp protection, 5.3 is short for nearly 34000t BB.

You note "1916", so, tech references to Jean-Bart or North Carolina are not realist.


Jef

Stability goes out the window.

[Jefgte]

Stability goes out the window.

220m...The hull is too short for 8x400 @ 29kts


Jef

[TexanCowboy]

...Stablity should go up. And, really, this vessel is much more similar to the Hood then it is to the "welded" North Carolinas, the 1930s Jean Bart, or the 33 knot Alaska, which was an oversized cruiser.

Also, I have considerable doubts that a 16'' quad could fit into 101 feet. Jean Bart was 108 feet, and a 15'' and a 16'' gun have a considerable size difference, if you've ever looked at pictures of, say, the Queen Elizabeth and the Colorado side by side....I'd think at least 117 feet of beam would be needed.

All of that was constructive critism at the design, not attempting to be an insult...I know I sounded irate in there, so...

[Jefgte]

I agree with Tex


Jef

[damocles]

Well.....................the original design was for 120 feet which was why it was broad beamed..........  ;D

[Guinness]

Alaska BC: 0.539

Colorado class (West Virginia) Draft: 31'8" (Normal), 32'5.75" (Full Load), 33'4.5" (Normal, 1944), 34'3.5" (Full Load, 1944)

The rest of the standards are pretty similar, maybe a foot less deep on earlier ships.

The Washingtons were also right around 32 feet. South Dakota drew 34'1.75" Normal, 35'0.75" Full load. Iowa 35'0.75" normal, 36'2.25" full load, 37'2" "emergency".

The most controlling factor in draft decisions was dry dock sill depth. The shallowest of these was at New York, at 32'11.5". Friedman hits on that topic when discussing the South Dakotas, as their light draft was a concern with respect to docking.

He also notes that Massachusetts passed through the Panama Canal in Feb. 1943 drawing 37.4 feet. So ~ 10m isn't crazy, I don't think. 11m might be pushing it.