Shifting my paradigm: Ship Sizes.

[Gargamel]

I'm trying to wrap my head around this.

The other day at work, I drove by the local port, and saw this (better paint job though, But I wanted to show how it was riding, all the other photos she's riding low):

http://photos.marinetraffic.com/ais/showphoto.aspx?photoid=37784

http://www.marinetraffic.com/ais/shipdetails.aspx?MMSI=212791000

I immediately wondered as to it's tonnage, and how easy would it be to sink with one eel.

So I google it on my phone as I went whizzing by, and was astonished by it's tonnage, 17,000!

Now I know that's fairly small by today's standards, but to me the ship did not look that big at all, I really was placing it in with the Granville size freighters we see ingame. I wish I had taken a photo fo it then, because maybe it was just the perspective I saw, but it really truly didn't look that big at all.

In size, how does this compare? The Nogat is 150m x 23m, 7.5m draft. Were the ships of the era that much smaller? As I look at the ESB right now, it seems it's a bit bigger than a large Merchant. But that's sitting at about 7,000 tons.

Where are they getting all the extra tonnage from in today's ships?

If anybody has some good links to shipbuilding techniques or what not of the day, I'd be interested to read this.

[desirableroasted]

Tonnage... what a can of worms.

Go here to have your head thoroughly confused:

http://en.wikipedia.org/wiki/Tonnage

SH3 models warships after displacement tons. That is, a Revenge class BB displaces about 31,000 tons (the weight of the water it would push out of an overflowing bathtub; nothing to do with the actual weight of the ship).

And I know I have read... but I cannot find it in my forum search ... that merchant "tonnage" in SH3 is based on Gross Register Tonnage. Which has to do with how much it can carry.

And these are two different things... but apparently make sense to people in the know.

Could some GWX folks weigh in on this? Because it is a bit of a mystery.

[Gerald]

Sirius Star is an oil tanker owned and operated by Vela International Marine.With a length overall of 1.090 feet (330 m) and a Capacity of 2.2 million barrels (350,000 m3) of crude oil, the ship is Classified as a Very Large Crude Carrier s VLCC.I guess it takes several eels here... ....:yep:

http://i.imgur.com/T2yZv.jpg

[Gargamel]

@ DR: Ok, I thought all ships went by displacement tonnage. So maybe the merchants were going by cargo tonnage, and were of similar sizes to todays ships, but just a different yard stick?

@ V: Ok... so what her tonnage? And I bet one good shot in the right place my light her up pretty good. Course, if she was running with just ballast, you may not have enough eels...... ANd wait a second.... thats 330m? That's what's considered a super tanker right? Bout the same length as a carrier? OK, it must have been my perspective I saw the Nogat at, cause in no way was I placing her as 1/3 - 1/2 the length of a carrier, or any big ship.

[Gerald]

162.252 tons, may need to use the aft eels.....perhaps

[Gargamel]

162.252 tons, may need to use the aft eels.....perhaps

Ok somebody needs to make a Philadelphia Project mod..... have one of these drop out of a time warp as an easter egg or something LOL.

[Gerald]

:up:

[Axeman3d]

So, if the Wikipedia article is correct, the GRT tonnage used in Silent Hunter is just the cargo spaces of the ship. In actuality if the ship tonnage was worked out in more modern GT tonnage, they'd be 3 or 4 times heavier at least. It makes the huge gap between modern and WWII sizes seem a lot closer.

[Hitman]

162.252 tons, may need to use the aft eels.....perhaps

That would be the Knight's cross with diamons for only six torpedoes and 1 ship :o ... not bad :D

[Mittelwaechter]

Philadelphia-Mod? Here you go...

http://www.abload.de/img/philadelphiaexperimentby1r.jpg

http://www.abload.de/img/philadelphiaexperimentsl9n.jpg

:DL

[ediko]

Nice pictures :haha:
Imagine how unhistorical (or rather how much more) the game would become if we had the real tonnage shown. I can already remember some patrols that would become 500k tonnage ones instead of the 50 :)

Or did the KM really measure the damage they inflicted by the amount of water they pushed out in the sea? :DL

[Sailor Steve]

Okay, here's the problem. GRT is based on internal volume, not weight. It is a number decided upon by the Insurer and the ship's Owner. It decides what the Insurer will pay to the Owner if the ship sinks, and it decides what the sub captain who sank the ship will be officialy credited with.

The number listed for the ship in the OP is Deadweight tonnage, which is how much cargo the ship is actually expected to carry. There can be a huge difference.

Here the modern Gross Tonnage is smaller - not quite 12,000.
http://www.shipspotting.com/gallery/photo.php?lid=401151

Given the ship's length - 150m - I would have guessed the GRT to be around 7000, the same as an Empire or Liberty ship; but the design is more modern and obviously built to maximize cargo space in ways not fully understood sixty years ago.

Second look: Here is the Wiki on Liberty Ships. Note that Nogat is both longer (150m vs 135m) and wider (25m vs 17m) with roughly the same draft (8.8m vs 8.5m). And note that the Liberty shows a displacement tonnage of over 14,000 tons, roughly twice the GRT which was about 7200 tons.
http://en.wikipedia.org/wiki/Liberty_ship

[Tessa]

Given the ship's length - 150m - I would have guessed the GRT to be around 7000, the same as an Empire or Liberty ship; but the design is more modern and obviously built to maximize cargo space in ways not fully understood sixty years ago.

Liberty ships are like the red shirt of cargo ships from that time period. Very little engineering went into designing them - thus why so many were lost initially, engineers never took into account the poor grade steel + low atlantic water temp = very brittle steel. Many Liberty ships cracked in half (literally) without a torpedo hit at all, the ships tonnage load was more than the ships hull could handle at such low temperatures causing them to frequently break apart.

While a simple solution was found to reslove this problem, Liberty ships were never designed to last very long; whole idea being quantity over quality. If the ship could be built in only several days time it only needed to make a couple round trips in order to be successful.

[Gargamel]

Ok, so merchant tonnage is based on amount of cargo they could hold, or would be insured for. Warships were displacement then. What about Liners (white star type stuff), I'm guessing that's displacement then too, since they (I'm assuming) didn't have a lot of room for bulk cargo where it wasn't feasible to list 5k tons for such a huge ship....

[Sailor Steve]

Liberty ships are like the red shirt of cargo ships from that time period. Very little engineering went into designing them - thus why so many were lost initially, engineers never took into account the poor grade steel + low atlantic water temp = very brittle steel. Many Liberty ships cracked in half (literally) without a torpedo hit at all, the ships tonnage load was more than the ships hull could handle at such low temperatures causing them to frequently break apart.

While a simple solution was found to reslove this problem, Liberty ships were never designed to last very long; whole idea being quantity over quality. If the ship could be built in only several days time it only needed to make a couple round trips in order to be successful.
All true, but what does any of that have to do with Gargamel's question?

[Gargamel]

All true, but what does any of that have to do with Gargamel's question?

Meh, it's not that far off topic.....

[Sailor Steve]

Ok, so merchant tonnage is based on amount of cargo they could hold, or would be insured for. Warships were displacement then. What about Liners (white star type stuff), I'm guessing that's displacement then too, since they (I'm assuming) didn't have a lot of room for bulk cargo where it wasn't feasible to list 5k tons for such a huge ship....
Actually they carried quite a bit of cargo. The largest liner sunk, SS Empress of Britain, was only carrying 600 tons of cargo, but SS Orcades carried 3000 tons of stuff.
http://uboat.net/allies/merchants/ship/643.html
http://uboat.net/allies/merchants/ship/2258.html

The trick with GRT was the 'volume' part. In theory they could carry that much cargo and more (the 'deadweight' part), and the fact that they were filled with people didn't change the calculations.

[Sailor Steve]

Meh, it's not that far off topic.....
I'm never concerned with staying on topic (which should be obvious by now). I just didn't see how it helped answer your question.

[Gerald]

Speculation,beyond question,leading in many cases, the answer to the question.

[Randomizer]

Liners were measured in GRT as well since interior volume was an important yardstick for passenger capacity.

Simple rule of thumb for a complex and somewhat arcane subject but:

Displacement tonnage is a measure of size and so relevant primarily to warships;

Gross Registered tonnage was a measure of revenue earning potential and so relevant to merchants, owners and destroyers of commerce; and

Deadweight tonnage relates primarily to reserve buoyancy and so is of most concern to shippers of bulk liquids (oil, water, LNG), insurers and accident investigators.

BdU usually tracked warship sinkings seperate from merchant tonnage since they are as apples and oranges but the USN freely mixed the two values when awarding credit. For Doenetz' "tonnage war" warship sinkings were entirely irrelevant (except as propaganda and a measure of a captain's aggressiveness for honours and awards) but as always there were exceptions and you will generally find Armed Merchant Cruiser tonnage measured in GRT even though they served as warships.

[desirableroasted]

And all of this works how in SH3?

[Sailor Steve]

And all of this works how in SH3?
In the game the ship gets assigned the tonnage you will be awarded for sinking it. For warships it's the displacement. For everything else it's the GRT. The GRT numbers are the average for the type of ship. In real life individual ships had different GRTs. The game can't do this because it would mean each individual ship had to be listed, and the space to hold the files would be enormous.

[Missing Name]

I have about 1.3 million GRT (minus about 300k warship displacement, I think) so far. Holy cow, that's going to be a lot of ship weight.

And remember, if merchants were awarded based upon total ship weight, different things will change the award. Cotton does not weigh the same as a load of M4 Shermans.

[Sailor Steve]

I have about 1.3 million GRT (minus about 300k warship displacement, I think) so far. Holy cow, that's going to be a lot of ship weight.

And remember, if merchants were awarded based upon total ship weight, different things will change the award. Cotton does not weigh the same as a load of M4 Shermans.
It doesn't matter. As I explained earlier, the GRT and the award are based on a number arrived at between the insurer and the owner. What cargo is carried is irrelevant - the GRT never changes.