[FT] Scale in Full Thrust

Do we know how heavy a mass 225 spaceship is in Full Thrust and how far 48MU's
is as far as weapon range? I think they're deliberately vague so they can
simulate a variety of genres, but I'm talking about within Tuffley's FT
universe.

Thanks!

> From: David Griffin <carbon_dragon@yahoo.com>

> Do we know how heavy a mass 225 spaceship is in

The calculated scale for FT in the Tuffleyverse is 1000 km per MU, and 15 to
20 minutes per turn.

I have seen references to 1 mass = 100 tons, but I'm not positive about that.

> On 6 Jun 2001, at 11:02, Allan Goodall wrote:

> > From: David Griffin <carbon_dragon@yahoo.com>

These were calculated, by myself and others, from the planets/orbits
rules in MT. If an Earth size planet has a radius of 6" then the distance
scale is known. And from the orbit rules and basic phyiscs the length of one
turn was calculated.

But MT also contains alternative rules where one edge of the table represents
the edge of a planet's atmosphere. There's no way of knowing what the scales
are when using those rules.

> I have seen references to 1 mass = 100 tons, but I'm not positive

Isn't that in FB1? As a suggestion only for GZGverse ships.

> --- steve@pugh.net wrote:
...
> > The calculated scale for FT in the Tuffleyverse is

Very clever

> But MT also contains alternative rules where one

Doesn't this make for small ships in the Tuffleyverse relative to some other
genre universes? A 250 Mass SDN would be 25,000 tons. I've seen various ships
described in various genres up to millions of tons.

How much does a big carrier like the Nimitz or a battleship like the New
Jersey or the Yamato weigh?

> "David Griffin" <carbon_dragon@yahoo.com> wrote:

> Doesn't this make for small ships in the

The USS Eisenhower weighs roughly 100,000 tonnes. The space shuttle is (again,
roughly) 100 tonnes. I forget where I got those numbers, but I got them a
while back when I was doing some relativistic problems in grad school...

> At 9:01 AM -0700 6/6/01, David Griffin wrote:

> Doesn't this make for small ships in the

Not very big. I've already resigned myself to the principle that
Honor Harrington SDNS are in the 2-3000 Mass realm in FT terms.

> How much does a big carrier like the Nimitz

The Iowas are 52,000 tons displacement, standard and 58,000 tons, full load.

The planned Montana class BBs (never built) would have been 65,000 tons,
standard and 70,500 tons, full load (12 18" guns over the Iowas
9)

Bismark was 45,000 tons, standard and 51,000 tons full load.

The Yamato's were 68,000 tons, standard and 71,600 tons, full load.

Nimitz CVs run 81,600 tons, standard and 91,500 tons, full load.

Mind you this is a measure of the weight of water that the ship displaces. It
is in effect the same thing, but it's not the "weight" of the ship.

[quoted original message omitted]

> From: David Griffin <carbon_dragon@yahoo.com>

> Doesn't this make for small ships in the

Yep, that's been discussed. They are a bit small.

> How much does a big carrier like the Nimitz

Turn of the century battleships, like the Japanese battleship Shikishima,
displaced 15,000 tons. That would be a small battleship by World War II
standards. I seem to remember the larger carriers today in the 50,000 ton
class, but you get the idea. A turn of the century battleship is about 150
mass points.

> Ryan Gill wrote:

> Doesn't this make for small ships in the

Not at all, the HH SDNs are in the 6-8000 Mass realm in TUFFLEYVERSE
terms.

Tuffleyverse terms =|= "FT terms".

If you don't play in the Tuffleyverse, the "1 Mass = 100 tons" simply does not
apply...

Regards,

> At 7:21 PM +0100 6/6/01, Bif Smith wrote:

There is more to it than armour on the military ships. Engines, hull, aux
gear, etc. also factor in. I've always understood it to be total displacement
of water...still hmm lets check with an expert...

From the sci.military.naval FAQ, Andrew Toppan is the maintainer, he also runs
a damn nice Naval Information site.

http://www.hazegray.org/faq/smn2.htm#B8

Section B.8: Ship Displacements

What do all those displacement terms mean? The following is a general guide;
the exact definitions vary from nation to nation and change over time.

* Light: Empty ship without any stores, fuels, munitions, crew, etc. aboard. *
Standard: As defined in the Washington and London Treaties: "the ship
complete, fully manned, engined, and equipped ready for sea, including all
armament and ammunition, equipment, outfit, provisions and fresh water for
crew, miscellaneous stores and implements of every description that are
intended to be carried in war, but without fuel or reserve feed water on
board."
*       Normal: As Standard, but with two-thirds supply of stores and
fuel (USN). Also can include all fuels, oils, and water. This is typically an
"average" operational displacement. * Full load: Fully loaded ship: all
stores, supplies, munitions, fuel, crew, etc. aboard. Wartime allowances as
applicable. * Deep load: Same as Full Load. * Deadweight Tons The carrying
capacity of the ship in tons, including cargo, crew, passengers, fuel,
supplies, munitions, etc. The difference between full load and light ship.

The following are measures of volume not weight, and are applied only to
merchant vessels:

* Net Registered Tonnage (NRT): Measure of the internal volume of the ship
which is used for for carrying cargo (i.e. excluding all areas not used to
carry cargo). * Gross Registered Tonnage (GRT): Measure of total internal
volume of a ship, in units of 100 cubic feet, with the following
areas excluded: machinery spaces, bridge/navigation spaces, and other
minor spaces essential to the operation of the ship.

> Oh, a HH SD would have a mass of 75000 mass (YES, 75 thousand!!!) with

Wow, I was low...I came up with the 2-3000 mass value just looking at
the concept for a LAC carrier assuming each LAC were in the 20-30
mass range.

The crew size and physical dimensions of the vessels also gives one an idea of
the scale of difference between HH and FT. But then, look how far in the
future HH is. Compare Battleship growth from 1900 to
1945. They started out at 14,000 tonnes or so and were at 60-70,000
tonnes by the end of WWII. Pretty good growth curve in 45 years.

All this talk about scale in FT has reminded me to post some questions to the
list.

I am writing a GURPS campaign that uses Full Thrust for the space combat...
nothing too different.

However, there is a twist to it. It is reminiscent of the SPELLJAMMER stuff
from the AD&D days. Basically, I am planning to use enchanted items as the
technology (i.e. use magic items for all of the ship systems). Granted, it
being enchanted items, the mass will have to be tweaked (i.e. how big is a
ballista?).

My question is, what scale should I use for mass? Assuming "ancient" ships
(galleons, viking ships, etc), what would I mass them at? That is the initial
question, because after that it would not be too hard to plug in the rest. I
just need something to base it all on. HELP.

Thank You (in advance)

On Thursday, June 07, 2001 1:21 PM, Jeremy Seeley
[SMTP:jseeley2@qwest.net]
wrote:
> However, there is a twist to it. It is reminiscent of the SPELLJAMMER
Granted, it
> being enchanted items, the mass will have to be tweaked (i.e. how big
ships
> (galleons, viking ships, etc), what would I mass them at? That is the

Doing some quick internet referencing, the seaworthy viking ships ranged
between 2000 lbs & 6000 lbs with crew of 15-25.

If you use 100 lbs displacement per mass, it should fit into the FT
construction quite nicely.

EG: Space Longship Mass: 40 (4000 lbs displacement) Hull: Average
Damage: 12; 3/3/3/3
CF: 2 (~ 40 crew members, needs extra to man weapons) FTL: Yes MD: 4 Firecons:
2
Bow Catapult (F) [Pulsetorp - seems to fit the all or nothing plunging
fire]
Port Ballista (FP/AP) [Class 3 battery)
Starboard Ballista (FS/AS) [Class 3 battery]
# If cargo space is required (above normal supplies) delete the Bow Catapult.
*****
Hope this is some help.

'Neath Southern Skies - http://home.pacific.net.au/~southernskies/
[MKW2] Admiral Peter Rollins - Task Force Zulu-Beta
[FITS-DP] World Cup Team: Australia II

I believe that Traveler used hydrogen displacement of the entire ship to
determine the mass of thier ships. I am drawing from memory of a game that I
owned and read as a teen (20+ years ago), but never had the chance to
play.

What jogged my memory was, back then, trying to understand how a crew quarters
that was mainly empty space would cost so much in mass. Once you realize that
it was measured against the mass of hydrogen displacement, it was easier to
understand. It includes the pressurized atmosphere, the materials used in
construction, accomidations, and the personnel.

-----
Brian Bell
-----

> -----Original Message-----
[snip]

> --

One Traveller tonne = 14 cubic m IIRC. Each tonne of mass equated to roughly 2
squares on the deck plans (the deck plans squares were 1.5mx1.5m and the
ceiling height was given as 2m, so one square actually had a volume of 4.5
cubic m. Two squares add up to 9 cubic m, the missing 5 cubic m was explained
away as space between decks, machinery space etc).

They explained how a simple model/1 computer could mass one tonne by
equating it to a PC, which sits on a desk, next to which is a chair for the
operator. The table occupies one square on the deck plan, the chair
a second square - two squares, therefore one tonne of the ship is
occupied.

I suspect this was a case of inventing a story to fit the facts :-)

> "Bell, Brian K (Contractor)" wrote:

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> On Thu, 7 Jun 2001, Tony Francis wrote:

> They explained how a simple model/1 computer could mass one tonne by

It certainly sounds like a serious case of ignoring reality. What do you mean,
rack mounted computers? What do you mean, frigates are full of them today?;)

Also sounds like they're confusing operator position (which you also had to
'pay' for, if I recall correctly) with computer.

Cheers,

> At 6:50 AM -0400 6/7/01, Bell, Brian K (Contractor) wrote:

Wow...what did they use Molars to represent the mass? Talk about a bloody
small yard stick. Its a common unit, just a bit small...

> Brendan Robertson wrote:

> > My question is, what scale should I use for mass? Assuming

Um... well. That - particularly the crew size - sounds more like the
smaller Swedish boats used in the Baltic and the Russian rivers. Norwegian
longships - the seagoing types - were rather bigger, with crews in the
40-100 man range. Not sure of their displacements though.

> EG: Space Longship

Um... there's no place to put a catapult on a Viking longship :-/ You're

thinking of the English warships built to combat longships; they had
sizable fighting platforms both forward and aft :-/

Later,

> Bif Smith wrote:

> Oh, a HH SD would have a mass of 75000 mass (YES, 75 thousand!!!) with

Which do you think is the heaviest: a modern MBT (60-70 metric tons), or
a block of solid balsa wood with the same external dimensions (width, length,
height)?

Hint: it's not the MBT...

...and I'm prepared to bet that the MBT has a far lower ratio of internal
empty space (accessways, cabins, fighting compartment etc.) to total hull
volume than the starship does.

Regards,

> "Bell, Brian K (Contractor)" wrote:

> I believe that Traveler used hydrogen displacement of the entire ship

> At 10:48 PM +0200 6/7/01, Oerjan Ohlson wrote:

Umm, I question that...Simply on the basis that an Abrams won't ever float
unless you magnify its dimensions such that it weighs less than an equivalent
volume of water does.

Less simply, we can look at the numbers (some one have better numbers, please
use them..)

Balsa wood is about 8lbs per cubic foot.

That abrams is 70 tons 180,000lbs ok, some basic facts... Outside dimensions.
This is the perfect cube size of an abrams. I don't know the presice cubic
footage. Any MAC loadmasters know?

93" x 387" x 144" Convert to Feet 7.75' x 32' x 12' Thats 2976 cubic
feet....divide that by the weight
and you get 60 lbs / square foot. Thats not even close, as again, I
don't know the outside perfect cubic size, so I'd wonder if given the
overall size, that an abrams is closer to 100lbs/square foot.

> ...and I'm prepared to bet that the MBT has a far lower ratio of

Umm, well, we could look at something that's a fair approximation, ballistic
submarines are able to float and are thus by nature less dense than water, so
you're probably right about that. Though I suspect that NSL ships are probably
more dense than average.

> [quoted text omitted]

[quoted original message omitted]

On Friday, June 08, 2001 5:28 AM, Oerjan Ohlson
> [SMTP:oerjan.ohlson@telia.com] wrote:
Norwegian

> longships - the seagoing types - were rather bigger, with crews in the

> 40-100 man range. Not sure of their displacements though.

Well, I did say QUICK internet referencing.

Details, details. That's never stopped a gamer from recreating historical fact
how they want to do it. It was mostly example to show possible solutions.
If I want catapults on my longships, I'll redesign them to fit. :-)~~

'Neath Southern Skies - http://home.pacific.net.au/~southernskies/
[MKW2] Admiral Peter Rollins - Task Force Zulu-Beta
[FITS-DP] World Cup Team: Australia II

***
If I want catapults on my longships, I'll redesign them to fit. :-)~~
***

Ever mindful of the appellation of ugly American, I never tell an Aussie
about beer. You might reconsider telling a Swede about Vikings. ;->=

The_Beast

-Douglas J. Evans, curmudgeon

One World, one Web, one Program - Microsoft promotional ad
Ein Volk, ein Reich, ein Fuhrer - Adolf Hitler

> ----- Original Message -----

Not exactly. The weight of the air is not zero. It simply is negligible
compared to the other stuff.

Greetings Karl Heinz

[quoted original message omitted]

> "K.H.Ranitzsch" wrote:

1 cubic foot ~= 0.03 m3, 8lbs / cubic foot = 282 lbs / m3.

282lbs = 128kg
or 0.128 tonnes / m3.

The mass of the M1 bounding-box-cube (87.7 m3) is more like 11 tonnes

Does this mean that Oerjan might not be right for once? <stunned>

Tony Francis schrieb:
> "K.H.Ranitzsch" wrote:
I've found 0.16 t/m3 on website, which doesn't really change the
conclusion.

> The mass of the M1 bounding-box-cube (87.7 m3) is more

Perhaps Oerjan was thinking of normal wood (which has in densities in the
range I assumed)?

Greetings Karl Heinz

> At 7:54 AM +0200 6/8/01, K.H.Ranitzsch wrote:
I
> also remember reading that tanks crossing a river underwater had a

An object will float or sink based on its overall density. Density is
mass/volume. The density  of the tank is higher than the density of
water. Thats with or without the hull sealed.

> > Less simply, we can look at the numbers (some one have better

Then use all metric...don't mix...

> > Balsa wood is about 8lbs per cubic foot.

Don't assume your numbers.

Balsa ranges from 8 lbs per cubic foot to 14 lbs per cubic foot.
Thats 144.14 kg/m3 to 252.25 kg/m3.

> > That abrams is 70 tons

That was short tons. 63.49 metric tons. or 63,490 Kg.

> I think 'perfect cube size' is what Oerjan was talking about.

> Total outside volume: 87,785832 m3

Shouldn't this be 87.78 m3 (L x W x H)? This is our total outside volume
either of our tank or of our balsa wood block.

63,490kg/87.78m3 = 723.28 kg/m3 this is the density of the tank.

Well assume a middle ground on the density of the balsa wood at
200kg/m3.

so, 200kg/m3 x 87.78m3 = 17,556 kg.

Balsa wood density = 200kg/m3 and 88m3 of it is 17,556 kg
M1 Abrams =723kg/m3 and all 88m3 of it is 63,490 kg.

> I think Oerjan is right.

Balsa wood floats. An Abrams doesn't. I don't see how it's size makes it
denser....

> Ryan M Gill wrote:

Yeah. Look what happened to some of the Mars missions in recent years. At
least one, if not two, of them were lost due to a mixing of metric and The
Other System. Wouldn't want your Abrams or block o'balsa to go
*boom*, would ya?  ;-)

Mk

> K.H.Ranitzsch wrote:

> > > Balsa wood is about 8lbs per cubic foot.

Yes, you're right. I had the densities of balsa and birch mixed up :-(

I'm a bit curious as to how Ryan got 70 metric tons to be 180,000 lbs though.
As I recall, 1 metric ton is 1000 kg and 1 kg is 2.2 lbs, so the

70-ton Abrams only masses about 155,000 lbs (must be the M1A2 SEP
version
though - the M1A1 is only 65 tons/145,000 lbs IIRC?).

Later,

> Ryan Gill wrote:

> An object will float or sink based on its overall density. Density is

Where did Karl mix? Tons are metric;1 ton = 1000 kg...

> > Balsa wood is about 8lbs per cubic foot.

Hm. 63,490 kg is only 140,000 lbs. Where did you get 180,000 lbs from?
(doesn't change the result much, of course, since I had the woods mixed up)

> I think 'perfect cube size' is what Oerjan was talking about.

It is the same. Us continental Europeans use commas to denote decimals -

causes no end of problems with USAmerican computer programmers who insist on
using decimal points...

> This is our total outside volume either of our tank or of our balsa

Pure water has a density of 998 kg/m3 (at 18 degrees Celsius), which is
a fair bit more than 723.28... <g> (Sea water is heavier still, of course.)

Later,

> At 10:43 PM +0200 6/8/01, Oerjan Ohlson wrote:

Short, Long or Metric. They aren't the same...:P

2000lbs for a short, 2240lbs for a long
> Hm. 63,490 kg is only 140,000 lbs. Where did you get 180,000 lbs

I think I made a mistake transcribing between calculator, conversion tables
and email...

Hmm, it should be 160,000 lbs for 80 short tons. Thats 72,576Kg

> It is the same. Us continental Europeans use commas to denote

You Eurpoeans, always changing standards on people. I'm surprised you don't
measure everything in pecks, furlongs, cords and stones...:P

Course I could have just used the South Eastern US unit of measure for weight
(and volume or quantity, its really flexible)...its rarely heard outside of
the South....it is of course the "mess".

"Your Grandpa brought home a mess of tomatoes from the farmers
market..."

I think the conversion factor from mess to ton is 134 or so.

> This is our total outside volume either of our tank or of our

We've added quite a bit of volume to this tank by taking outside box
(rectangular) dimensions. A conformal volume would be even higher. The space
occupied only by the gun and over the back engine deck would add quite a bit
of density were we not taking that into account.

> At 10:32 PM +0200 6/8/01, Oerjan Ohlson wrote:

A neat page on the densities of woods...

http://hypertextbook.com/facts/2000/ShirleyLam.shtml

> I'm a bit curious as to how Ryan got 70 metric tons to be 180,000

M1A2 is 80 tons, 160,000lbs. I've not done conversions like this in years so
it was a bit difficult pulling those procedures from the depths of my brain. I
was reading 160,000 lbs and transcribing 140,000 or 180,000...It' would have
helped had I been doing it on paper with a calculator instead of just keeping
notes on the computer screen...

> At 6:43 AM +1000 9/6/2001, Oerjan Ohlson wrote:

In school prior to metric conversion in Australia: 1 ton = 2240 pounds 1 tonne
[nb] = 1000 kg = 2200 pounds approximately

So you can both be correct depending where you were taught. You do not need to
remind me of what that extra 40 pounds means out in
space...

MarkS

From: "Ryan M Gill" <rmgill@mindspring.com>

> Course I could have just used the South Eastern US unit of measure

From: "Ryan M Gill"
> Course I could have just used the South Eastern US unit of measure

AEBrain asked: How many messes in a passle?

They don't convert, any more than perch and cord convert to each other. I only
recall "mess" being used for produce or fish.

> At 11:56 AM -0400 6/9/01, laserlight@quixnet.net wrote:

I've seen it applied to other food stuffs. Say, a 'whole mess of sliced
ham'....

I guess it's not unlike a lot.

In message <00cd01c0ef00$eabf06c0$02cd6441@jeremy>
> "Jeremy Seeley" <jseeley2@qwest.net> wrote:

> All this talk about scale in FT has reminded me to post some questions
Granted, it
> being enchanted items, the mass will have to be tweaked (i.e. how big
ships
> (galleons, viking ships, etc), what would I mass them at? That is the

That is very spooky - I'm working on something very similar (GURPS
campaign, using _very_heavily_modified_ spelljammer background - plus
other bits I'm nicking from all over the place - with FT for ship combat
if necessary).

If using 'standard' spelljammer designs - I'd use 1 FT MASS of hull = 1
spelljammer 'Ton' of hull, where IIRC 1 spelljammer 'ton' equalled 100 cubic
feet.

In message
<20010606150223.ZYJW2764.tomts14-srv.bellnexxia.net@[209.226.175.22]>
> Allan Goodall <awg@sympatico.ca> wrote:

> > From: David Griffin <carbon_dragon@yahoo.com>
I tend to think of this as 1 mu = 1000km, 1 turn = 1000s, in which case 1
thrust =.2g (so thrust 5 = 1g).

It should be noted that under this scale, a Phalon plasma bolt is almost
as big as the Earth :-)

For other genres - using range values quoted in the series (where I
remember them):

B5 - typical engagement ranges in 100's of km, so 1mu = 10km
Star Trek - typical engagement ranges (as quoted in script - _not_
apparent visual ranges in FX) - 10's of thousands of km, so 1mu = 1000km
Andromeda (from the few episodes I watched) - typical engagement ranges
in multiples of light seconds - 1mu = .1 to 1 light seconds, or 30,000
to 300,000 km (and missiles move at near lightspeed).

In _written_ SF, the ranges can get a lot bigger :-).

[quoted original message omitted]

In message <002f01c0f191$61fd0e20$d7b4193e@inty>
> "Bif Smith" <bif@bifsmith.fsnet.co.uk> wrote:

> ----- Original Message -----

Well, it comes from playing arround with the standard equations of
motion and the Full Thrust rules - not that due to a simplification used
by FT, there could be an error of x2 in the accelleration value (which
I don't worry about ;-)
As most ships have a maximum thrust of between 4 and 8, which is
equivalent to between .8 and 1.6 G - which seems quite mild :-)

Just checked, g=9.8 m per s squared.
> > It should be noted that under this scale, a Phalon plasma bolt is

Yes, I wondered that - of coarse, IIRC the scale was chosen before FB2
came out.
> > For other genres - using range values quoted in the series (where I
Depends - we can sense things quite well over long distances, but AFAIK
there are may be limits on how well 'beams' (whatever they happen to be) can
be focused over long distances. Also lightspeed delays on aiming will become
significant over long ranges.
Depends how much 'reality' you want, I guess :-)

I just use the Traveller (1st Ed) stats. 1 MU (inch) = 2500km, 1 turn = 1000s
( to 6 minutes. 1 thrust ( 1 G

Michael Brown

[quoted original message omitted]

In message <01C0F181.5397B3E0.mwbrown@veriomail.com>
> Michael Brown <mwbrown@veriomail.com> wrote:

> I just use the Traveller (1st Ed) stats. 1 MU (inch) = 2500km, 1 turn

Err... I think 1000s = 16 2/3 minutes ;-)

Yeah, that's what I meant!

Michael Brown

[quoted original message omitted]

From: "Alan and Carmel Brain" <aebrain@austarmetro.com.au>

> From: "Ryan M Gill" <rmgill@mindspring.com>

> > I think the conversion factor from mess to ton is 134 or so.

> Some days back, Ryan Gill wrote:

> I'm a bit curious as to how Ryan got 70 metric tons to be 180,000 lbs

Have checked the figures now. According to TACOM the M1A2 is 69.5 short tons,
ie. 139,000 lbs or equivalently 63 metric tons.

Now I'm no longer curious how you got 180,000 lbs, but I *am* curious about
the "80 tons" figure <g>

Regards,

> At 9:16 PM +0200 6/14/01, Oerjan Ohlson wrote:

It was after a quick search of the web. Looking further, GDLS says 69.4 tons
for the M1A2.

http://www.gdls.com/programs/m1a2.html

And the Logistics people in the army say 69.54. So perhaps I miss wrote in
that one too....

http://www.tacom.army.mil/gcss/pmabrams/vehicles/m1a2char.htm

Could be a difference of wet and dry. How much does 40 rounds of 120mm sabot
and all the fuel for that beast weigh in at.

Though I really think perhaps I mis-wrote that as well.

> Ryan Gill wrote:

> Have checked the figures now. According to TACOM the M1A2 is 69.5

> tons for the M1A2.

69.5 tons is the combat load, so should include full tanks and full magazines.

> Though I really think perhaps I mis-wrote that as well.

Then there are two of us :-)

Regards,

> > > The calculated scale for FT in the Tuffleyverse is

> Doesn't this make for small ships in the

Yes, it does. A good comparison would be the mass of today's aircraft, rather
than ships. Which makes sense. A fully fuelled 747 is what, 200 t?

> How much does a big carrier like the Nimitz

In orbit, very little. Microgravity and all that.

But seriously, a standard battleships of WW2 was 35,000 t, a big one like
Bismark or New Jersey about 50,000 t, and Yamato and Nimitz are both about
80,000t.

A far, far better analogy is the size of ships at about the turn of the 19th
century. The standard "ships of the line" were about 12,000 t, with protected
cruisers on the order of 10,000 t, and light cruisers something like 5,000 t.
It wasn't until the Dreadnaughts of 1905+ that
ships went over the 20,000t mark. (Sweeping
generalisation - there were a number of exceptions)