Rooms upon a Starship

[aramis]

Forgive me, I was under the impression that a dTon was a 1.5m cube, though I have to admit I do have some confusion about it as an abstract concept. Could you point me toward more information about it?

For my starship visualization I'm running on the assumption that 1 hull ton = 4 dTons, and that a deck, from bottom to top, including bulkheads/framing, etc, crawlspace and "machinery between decks" is on average 5m. Is this too generous a guideline?

It's never been a 1.5m cube.

it's defined in CT as about the displacement of 1 ton of Liquid Hydrogen (which runs 13.75 to 14.15 cubic meters, depending upon pressure and temperature; it's not liquid at STP).

In CT's The Traveller Book, page 56:

The Hull: Hulls are identified by their mass displacements, expressed in tons. As a rough guide, one ton equals 14 cubic meters (the volume of one ton of liquid hydrogen). When hulls are constructed, they are divided into an engineering section for the drives and the main compartment for everything else. All drives and power plants must be located in the engineering section, and only drives and power plants may be placed in that section. All other ship components, including fuel, cargo hold, living space, and computer, must be located in the main compartment.​

Ibid., page 67:

DECK PLANS
If the referee or the designer should feel that detailed deck plans for a ship are required, then they may be drawn up using square grid graph paper. The preferred scale for ship interiors should be 1.5 meters per square, with the space between decks (floor to ceiling height) put at about 3.0 meters. One ton of ship displacement equals approximately 14 cubic meters. With a 3.0 meter floor-to-ceiling height, one floor square (1.5 meters by 1.5 meters by 3.0 meters) equals 6.75 cubic meters. Two such squares equal 13.5 cubic meters, or approximately one ton.​

The customary "deckplan scale" is 1.5m squares, 3m tall, plus about 0.1m of deck, 2 squares to the Ton; this is 13.95 cubic meters. Many deckplans for CT only work at 3 squares to the ton; that's a 2m ceiling. (And not a big issue. The Type S plans only have full 3m clearance aft of the cabins.)

MegaTraveller used 1.5m grids, but left out the deck planks, and is thus 13.5 cubic meters per Td, and uses that throughout the rules. (Sigh.)

TNE used 2m grids - and 3.5m tall decks - for 14 cubic meters exactly. But note that decks would be included in that 3.5m.

 

[Magnus von Thornwood]

The Baron Slow.

Wow, that's an impressive list to be sure and some solid suggestions.

I didn't really see this particular vessel supporting families, though, but I suppose an enterprising captain/owner might refurbish for that. Its primarily a work-horse hauler with crew doing shifts, so each of the facilities are a bit more scaled down. I visualize some of the rooms doing double duty - briefing room becomes a small scale cinema, for example.

The Laundromat, lack of septic tanks/waste recycling are the most grievous omissions I think.

I like the idea of a "welcoming" room near the main access, though I'm thinking of it as a customizable room serving a variety of greeting purposes (in the particular ship I'm creating, it might end up being more of a "planet-side part assembly room". Not only that, its already supported by my novel in a way! (there is a scene mentioned which implies it takes place in such an area)

Got the workshops, emergency store caches (tied into the vaccsuit stores), I've got airlocks out the wazoo.

Dedicated rooms for trades training. Interesting idea, why not just use the workshop instead, or is it because its use most of the time? I'm a fan of training on the job. Or am I missing something here? Keeping trainees away from critical systems? Its a good idea though.

Safe/panic rooms are a good idea too. Not sure if they'd have crash couches or not for rough flight conditions?

Thanks to all for your suggestions and to Matt123 for your truly extensive list. I think I can fill up the empty bits without feeling guilty now!! (and get these plans done, which I'm hoping Baron Thornwood will be happy for)


Not sure about the rooms, cabins and overheads, but I'll do my best.

Yeah, I totally spaced the connection to this thread and your ship. Derp. And yes, yes I will.

 

[SanDragon]

A 1 dT volume is a block 1.5 meters wide by 3 meters long by 3 meters tall. In other words, a deck is 3 meters bottom to top. However, the typical person does quite fine with about a 7 to 8 foot - 2.1 to 2.4 meter - ceiling. That leaves you 60-90 centimeters between decks for gravitics, wiring, plumbing, air and environmental equipment, and so forth.

That's 20 to 30% of the total volume of any given space - lots of room there for the life support and recycling machinery without needing to have a dedicated room for such stuff. Or at least, if you want dedicated rooms, they don't need to be terribly big - just big enough for boilers, controls, storage and settlement tanks and suchlike machinery that would need to be big.

Possibly the origin of the 20% leeway for deck plans?

 

[Carlobrand]

...The customary "deckplan scale" is 1.5m squares, 3m tall, plus about 0.1m of deck, 2 squares to the Ton; this is 13.95 cubic meters. Many deckplans for CT only work at 3 squares to the ton; that's a 2m ceiling. (And not a big issue. The Type S plans only have full 3m clearance aft of the cabins.)

...

Oh.

OH!

Dagnabit! I never thought of that! No wonder I can't get the forward hatch opened!

Possibly the origin of the 20% leeway for deck plans?

Maaaaaaybe. I always figured that was where they were stowing the life support equipment, since it wasn't showing up on any of the official deckplans.

And then Aramis pointed out that 2 meter bit. Now I have to completely rethink the scout.

 

[GRNDL]

It's never been a 1.5m cube.

Well, that puts the kibosh on a few things.

Looking back at my original calculations, when I was trying to figure out hull-tonnage from a specific volume (100*40*20meters) I had the definition right. But somewhere along the line saw too much of a relationship with deck squares for the drawing of the plans and must have mussed up the definition.

Hmmm, not sure where to go with it now, since I'm back at looking at a 6kTon vessel I had calculated, rather than the 1 .5kton one I've specced outand the T5 rules don't currently cover that. GRRRR.

re: Deck separation...

Ok, let me dig my hole a bit further.

Wording in the T5 rules state (p333)
Deck squares. One ton equals two deck squares when creating deck plans (with a 3m deck separation)

which sounds more like there is 3m between decks, which is how I arrived at the 5m thing. Seemed logical to me, but you're suggesting that a deck is conveniently the same height as the dTon it consumes, so a 2m high deck-floor to deck-ceiling and 1m substructure/bulkhead framing between decks?

Confused further, deck cubes: One cube is 0.25 tons, so one cube equals four 1.5m cubes, so a deck cube only reaches up 1.5m, which isn't even half of one deck with a 3m separation, so I'm wondering what the purpose of this abstract is in planning volumes.

Edit: After rereading your post, this stood out more:
With a 3.0 meter floor-to-ceiling height, one floor square (1.5 meters by 1.5 meters by 3.0 meters) equals 6.75 cubic meters. Two such squares equal 13.5 cubic meters, or approximately one ton.

So, the abstract idea is that one deck-square is just the bottom side of two deck-cubes stacked on top of the other? That sort of makes sense and in terms of defining units, seems to boggle the idea of square vs. cube at the abstract level. Why not just define a deck-cube as a unit extension of the deck-square? Anyways...


I think a lot of my confusion comes from starting out with a specific sized ship I needed to make, rather than build the ship first, then draft schematics to the calculated volume from the ship's stats.

Maybe this has become more of a T5 issue, but with the definitions more or less being the same, I figured I'd just continue the thread here.

 

[GRNDL]

Yeah, I totally spaced the connection to this thread and your ship. Derp. And yes, yes I will.

Well... it seems as though I've just encountered some major setbacks. :frankie:

And just when things were going good.

 

[Carlobrand]

... Many deckplans for CT only work at 3 squares to the ton; that's a 2m ceiling.

I had a sudden hope that this might help resolve the Broadsword mess, but then we end up with a flying saucer with a couple of towers sticking out the top.

sigh ...

Well... it seems as though I've just encountered some major setbacks. :frankie:

And just when things were going good.

Don't you just hate that? Design's coming along nicely, and then you realize you missed some rule or another?

 

[aramis]

the broadsword might be 1m or 1.25m grids...

note that 2m separation floor to ceiling is 6' 6.5"or so. uncomfortably low for me, really a problem for my friend Ron (6' 1.5" an 6 '6")...

 

[Reban]

re: Deck separation...

Ok, let me dig my hole a bit further.

Wording in the T5 rules state (p333)
Deck squares. One ton equals two deck squares when creating deck plans (with a 3m deck separation)

which sounds more like there is 3m between decks, which is how I arrived at the 5m thing. Seemed logical to me, but you're suggesting that a deck is conveniently the same height as the dTon it consumes, so a 2m high deck-floor to deck-ceiling and 1m substructure/bulkhead framing between decks?

Confused further, deck cubes: One cube is 0.25 tons, so one cube equals four 1.5m cubes, so a deck cube only reaches up 1.5m, which isn't even half of one deck with a 3m separation, so I'm wondering what the purpose of this abstract is in planning volumes.

Edit: After rereading your post, this stood out more:
With a 3.0 meter floor-to-ceiling height, one floor square (1.5 meters by 1.5 meters by 3.0 meters) equals 6.75 cubic meters. Two such squares equal 13.5 cubic meters, or approximately one ton.

You could think of it as 3m from deck surface to deck surface. I allow 2.5m floor to ceiling height.

I use 0.25m above the ceiling for all ducts, atmospheric and liquid pipes (on ships and spaceships access to these in an emergency is important). As long as there is gravity you can see a leaky pipe drip or gases venting.

The 0.25m below the deck sole contains gravity plates and structural members supporting the deck and internal walls (not the same as bulkheads).

This is all IMTU and very generous in terms of volume, but its a generalization. IMTU these are the guidelines that naval architects are given for human standard crews.

For the T5 ton you are starting to get the right image in your head. Somewhere in the book there is an image of a 1 ton cargo pod that is 1.5m thick, 3m wide and 3m high. There's is also a page of references for what 1 ton equals and the subdivisions like 0.25 of a ton.

Here's the kicker though. Traveller isn't MineCraft. Not everything is made from neat cubes of volume. Some spaces are a bit over some are a bit under. In your head you have to make the mental leap to say this ship displaces x tons and I can fit a deck square grid to its outline to represent its internal volume with a margin of error (20% under CT I think?).

 

[Carlobrand]

the broadsword might be 1m or 1.25m grids...

note that 2m separation floor to ceiling is 6' 6.5"or so. uncomfortably low for me, really a problem for my friend Ron (6' 1.5" an 6 '6")...

Broadsword as designed is a 31.5 meter sphere: a 1200 dT volume (1212, to be precise), not counting the legs and the wee bit of cutter sticking out the back of the sphere. Getting it to within spitting distance of 800 dT requires taking the grid to about 1.3 meters - takes it to a bit over 27 meters diameter. That gives ample head room but plays havoc with the two cutters embedded within it: they become the size of a ship's boat unless you modify the design to accommodate them. Figure in the two extra cutter modules stored inside a Broadsword, and you end up with a fairly radically modified interior deckplan to accommodate the cutters and the extra modules.

I'm working on a 27-meter Broadsword deckplan. It is ... very challenging.

 

[Shadowrunner]

A ship this size I will usually give a couple of crew members like Tech Officer or Electrician and give them equipment lockers and workspaces.

I imagine like on old sailing ships, there was a constant production line of all kinds of things from making clothing, to repairs, to making ammunition, to stitching sails.

 

[SanDragon]

Broadsword as designed is a 31.5 meter sphere: a 1200 dT volume (1212, to be precise), not counting the legs and the wee bit of cutter sticking out the back of the sphere. Getting it to within spitting distance of 800 dT requires taking the grid to about 1.3 meters - takes it to a bit over 27 meters diameter. That gives ample head room but plays havoc with the two cutters embedded within it: they become the size of a ship's boat unless you modify the design to accommodate them. Figure in the two extra cutter modules stored inside a Broadsword, and you end up with a fairly radically modified interior deckplan to accommodate the cutters and the extra modules.

I'm working on a 27-meter Broadsword deckplan. It is ... very challenging.

Please make a San check...