Der Fuhrer battleship converted to carrier

You guys keeping talking about the need to hit a target. Hitting is always nice, but with guns that size, I wonder whether a near-miss might be enough versus most targets. Near misses with OTL weapons were often reported to have done critical damage as it was.
 
2000 feet long 55 foot draft maybe 40 feet freeboard.....so that's what a beam 2000 feet long 95 feet deep and 300 feet wide with a concentrated load midships with lots of holes in the upper surface...:eek::eek::eek:......and how many 100,000's of horse power applying a force at one end.find me a structural engineer and I bet he laughs real hard at that.:p:p:p

but then I guess it's really the fire support for the unmentionable sea mammal.:p:p:p:p
 
Just for s$%^ and giggles, estimate the wetted area as an ellipsoid.

a=draft, 55 ft
b=length/2, 1000 ft
c=beam/2, 131 ft

From wikipedia, the area of an ellipsoid can be approximated as this nasty thing:

051d022bf89c229320507af2a21b6388.png

Where p is a factor of about 1.6.

Our wetted area is half of that, though there's some fudge because of course it's a bit bigger than that because it's not a semi-ellipsoid, and by observation of the hull form and an ellipsoid I think it'll have more area. Say...50% more? Wetted area is thus 66,761 m^2. From this paper, coefficient of drag using the wetted area should be something like 4*10^-3, and thus using the density of water (1000 kg/m^3) we can solve for drag via good old D=(0.5*density*v^2)*(area)*(drag coefficient). Power for steady speed is drag times the velocity, so I can calculate power requirements. Say that the prop is 80% efficient in turning shaft power into power in the water, and we can find the required engine output.

Results for sample top speeds:

Code:
Speed        Drag     Power Req'd
20 knots    14 MN    243,718 HP
22 knots    17 MN    324,388 HP
25 knots    22 MN    476,011 HP
27 knots    26 MN    599,637 HP
30 knots    31 MN    822,547 HP

So...you know. To make 30 knots, it'd only take the thrust equivalent of the Saturn V, and about 613 MW of power. This would be about 6 A4W reactors, or twin A1B reactors (based on this page listing 104 MW shaft power for the A4W and this one saying the A1B has about triple that). Or about 8 of the largest diesels existing in our world:

largest-diesel-engine.jpg


Well, that was fun mental floss. People can point out where I screwed up, and I'll deal with it in the morning.
 
well I think the largest diesel at the time was a B&W powering a fixed generator in Copenhagen....still there and still works.
so at 22,500 hp thats what some 40 odd for main propulsion and say 4 or more for electrical generation.Now being good industrious German engineers we end up with 4 of the worlds largest gear boxes/reduction gears.maybe the same guys who brought you that ever reliable tiger tank.:D:D:D
 
Just for s$%^ and giggles, estimate the wetted area as an ellipsoid.

a=draft, 55 ft
b=length/2, 1000 ft
c=beam/2, 131 ft

From wikipedia, the area of an ellipsoid can be approximated as this nasty thing:

051d022bf89c229320507af2a21b6388.png

Where p is a factor of about 1.6.

Our wetted area is half of that, though there's some fudge because of course it's a bit bigger than that because it's not a semi-ellipsoid, and by observation of the hull form and an ellipsoid I think it'll have more area. Say...50% more? Wetted area is thus 66,761 m^2. From this paper, coefficient of drag using the wetted area should be something like 4*10^-3, and thus using the density of water (1000 kg/m^3) we can solve for drag via good old D=(0.5*density*v^2)*(area)*(drag coefficient). Power for steady speed is drag times the velocity, so I can calculate power requirements. Say that the prop is 80% efficient in turning shaft power into power in the water, and we can find the required engine output.

Results for sample top speeds:

Code:
Speed        Drag     Power Req'd
20 knots    14 MN    243,718 HP
22 knots    17 MN    324,388 HP
25 knots    22 MN    476,011 HP
27 knots    26 MN    599,637 HP
30 knots    31 MN    822,547 HP

So...you know. To make 30 knots, it'd only take the thrust equivalent of the Saturn V, and about 613 MW of power. This would be about 6 A4W reactors, or twin A1B reactors (based on this page listing 104 MW shaft power for the A4W and this one saying the A1B has about triple that). Or about 8 of the largest diesels existing in our world:

largest-diesel-engine.jpg


Well, that was fun mental floss. People can point out where I screwed up, and I'll deal with it in the morning.

Your math is fine. 822,547 HP. Wow.

For comparison the Bismarck's power plant was 12 boilers powering 3 turbines producing 150,170 SHP. So half a dozen of those; 72 boilers powering 18 turbines to produce something over 900,000 HP. (The extra allows for electrical generation and periodic maintenance). That's enough power for a good-sized city, and would require several hundred personnel to operate and maintain it.

alfredtuomi said:
2000 feet long 55 foot draft maybe 40 feet freeboard.....so that's what a beam 2000 feet long 95 feet deep and 300 feet wide with a concentrated load midships with lots of holes in the upper surface...:eek::eek::eek:......and how many 100,000's of horse power applying a force at one end.find me a structural engineer and I bet he laughs real hard at that.:p:p:p

No bet. There would have to be so much framework that the interior space would be as cramped as a U-boat's to get everything needed into it. No tight turns, either; a hard turn at full speed might break it like a green twig.
 
Now being good industrious German engineers we end up with 4 of the worlds largest gear boxes/reduction gears.maybe the same guys who brought you that ever reliable tiger tank.:D:D:D
Or someone decides that even increasing it to eight shafts means impossible complications, so they throw out tradition, and make the thing diesel-electric.
 
Approximately 77,000,055,000. A life-sized model of a sports sedan that would have weighed 1.5 (or so ) tons took approximately 165,000 tiles. I assumed 700,000 tons as a target. Feel free to check my math. :)

I meant a scale model. I should have mentioned a lego model to the same scale as the lego Yamatos that exist. However, I love your idea of a 1:1 model as well. Go all the way crazy! :D
 
Top