Airlocks/ship's lockers & corridors/passageways in deckp

[snrdg121408]

Morning all,

One of the items that have always given me trouble in drawing Traveller deckplans centers around the volume of airlocks, ship's lockers, and passageways, aka corridors or hallways. MgT, unfortunately, still does not help me out in getting a good handle on the volume of the components listed in the subject line. For most of the design sequences not defining the volume of an airlock, ship's locker, and passageways are one factor in having deckplans the exceed the ship's listed displacement tons.

Volume in MgT as well as all the Traveller flavors is measured as 1 displacement ton, with two exceptions equals, 14 cubic meters of hydrogen. MT uses 13.5 cubic meters and GT uses 500 cubic feet. With the exception of GT, the scale of a deckplan uses 2 squares to represent 1 dton, which equals 1.5 meters wide by 3 meters long, and an overhead, ceiling for landlubbers, height of 3 meters.

Most of the flavors of Traveller state that a ship can have a maximum of 1 airlock per 100-dtons of hull but not how much volume the component takes up. Many of the deckplans shows at least two airlocks, one adjacent to the bridge and a second one adjacent to the Engineering Spaces. MgT Core book states the standard airlock, page 137, is designed to fit 3 people in vacc suits. Unfortunately, like most of the Traveller design sequences MgT does not mention the volume.

Unfortunately, I'm not sure if the examples shown on the deckplans in the MgT if the airlocks are 1-dton or 0.5-dtons. The Scout/Seeker deckplans, like a majority of Traveller plans, has some issues matching the dtons of components in the design worksheet. Per the design worksheet the electronics requires 2-dtons of space which I think equals Avionics is 1 square. This indicates, to me anyway, that 1 square = 2 dtons. Moving to the bridge I count either 5.5 or 6 squares making the bridge 11 or 12 dtons not 10 dtons listed on the worksheet. The staterooms appear to match the spreadsheet 16-dtons using 2-dtons per square if you do not include the passageway. Looking at the cargo hold for the two there are 13 squares, 15 if you count the Drone launch area. This does not match with the cargo space listed on the worksheet. Engineering matches the worksheet 16-dtons total if the squares represent 1-dton.

Ship's lockers, in many of the other variants, are mentioned but not how many or how much volume they take up. MgT core book on page 110 states that, which is refreshing, a ship has a ship's locker. Unfortunately MgT, like most Traveller variants, does not define how much volume and only 1 ship's locker regardless of ship size.

Of course the volume of a ship's locker is going to vary depending on the ship's lockers purpose. A ship's locker designated to store a ship's handguns, rifles, and ammo/power packs will take up a small space, just for scale, say 0.25-dtons. While a ship's locker designated for vacc suit storage and suit-up room might be a small 1-dtons. Again, I can't tell from the MgT deckplans how much volume the component takes. Another minor gripe, even with MgT, is the deckplans, when shown, have only 1 ship's locker. In theory, and if the GM is being nice, anything the players may need is stored in the ship's locker. What happens if the ship's locker is destroyed. Everything in the locker is destroyed which usually includes vacc suits, weapons, and the items that can be used to repair damage. At minimum any ship, civilian or military, will have at least 1 ship's locker. As the vessel get larger they need more ship's lockers that are spread throughtout the ship. In the Navy each compartment had a ship's locker used for damage control equipment and basic medical stuff. The larger the ship the more lockers.


Passageways which is traditional seafaring speak for corridors or hallways are another item not very well defined in most of the Traveller design systems. Most of the design sequences state in some fashion that a standard 4-dton stateroom includes part of a ship's passageway. Unfortunately, they don't state how much of the stateroom's 4-dtons are used to make up corridor/passageway. Again going to the Scout/Seeker deckplans outside the 4 staterooms are 4-squares representing a passageway. Do the 4 squares represent 4 or 8-dtons of volume?

I'd like to recommend the following
For a standard 3-person in vacc suit airlock be 0.5-dtons.
The minimum size for a ship's locker should be 0.25-dtons.
A passageway is a minimum of 0.25-dtons.

Respectfully,

 

[brionl]

My advice would be to not worry so much about it. Just pick a shape that is approx. the right size and draw in stuff that looks good.

 

[AndrewW]

I have to agree with you. It would be nice for deckplans if all this could be worked out. Ship's lockers take up space on the deckplans, but no tonnage (just as one example). This makes plans not match up to the listed tonnage. Not to mention that some of the official deckplans don't match up tonnage wise to the used space.

 

[Golan2072]

A few deckplanning guidelines I've used before (in CT, but are probably workable for MGT as well):

1) The bridge tonnage given in LBB2 includes more than simply the physical bridge itself. While the exact composition of this tonnage is not given in LBB2, deck plan design calls for a more precise definition. I suggest the following: 50% of the bridge tonnage would be the actual Bridge, with workstations and workspace for the command crew (Pilot, Navigator, Chief Engineer, Chief Gunner, and, in larger ships, also CO and XO); 25% would be communication arrays and avionics (to which the computer tonnage should contribute as well, see below); 12.5% would be the ship's airlock(s); and 12.5% would go to office space, a "ready room" and a fresher for the bridge and command crew.

2) LBB2 says that the Stateroom tonnage includes more than just the stateroom itself, but does not give concrete data on this subject. I suggest that the actual Stateroom (3x3x3 meters, includes a bed or a bunk bed, a desk and a fresher) will take 50% (2 dton per stateroom); 18.75% (0.75 dton per stateroom) should go to the ship's Galley and Medlab; 6.25% (0.25 dton per stateroom) should go to the Ship's Locker/Armory; 12.5% (0. 5 dton per stateroom) should go to Life Support; 6.25% (0.25 dton per stateroom) should go to landing gear/fuel scoops/docking equipment; and 6.25% (0.25 dton per stateroom) should go to Corridors/Passages.

 

[GypsyComet]

Hard numbers are often not going to work very well. If the quarters, access and control areas of a deckplan are close to the aggregate tonnage available to staterooms and bridge, that's close enough. If you want a large and dedicated galley, buy a lab. That's what kitchens are, after all.

 

[Infojunky]

First off, there is a Yahoo Group devoted to Deckplans, and a lot of these issues have been and are hashed out there.

One of the items that have always given me trouble in drawing Traveller deckplans centers around the volume of airlocks, ship's lockers, and passageways, aka corridors or hallways.

Ok, in general there is a 20% slop factor, this has been standard assumption since CT.

Volume in MgT as well as all the Traveller flavors is measured as 1 displacement ton, with two exceptions equals, 14 cubic meters of hydrogen. MT uses 13.5 cubic meters and GT uses 500 cubic feet. With the exception of GT, the scale of a deckplan uses 2 squares to represent 1 dton, which equals 1.5 meters wide by 3 meters long, and an overhead, ceiling for landlubbers, height of 3 meters.

You missed TNE which use 2 meter squares with a 3.5 meter deck height.

But, the exact volume you use really isn't a big issue as 14m^3 ≈ 13.5m^3 ≈ 500 cuft, as long as you are internally consistant.

Most of the flavors of Traveller state that a ship can have a maximum of 1 airlock per 100-dtons of hull but not how much volume the component takes up.

My standard lock is usually 4 squares (3 meter square) and personnel scale lock is 1 square (1.5 meter square) location is generally dictated by conformation of the ship. I try to keep a quarterdeck with lock at ground level for ships that land. And on the Main deck on ships that don't. With that engineering locks and cargo locks are placed as needed.

Cargo locks tend to be size to the amount and types of cargo transported. Frequently a hold will only have an outer door, with a standard lock leading from the hold to the rest of the interior of the ship.

Unfortunately, I'm not sure if the examples shown on the deckplans in the MgT if the airlocks are 1-dton or 0.5-dtons. The Scout/Seeker deckplans, like a majority of Traveller plans,

Which version of the TMB do you have? The initial release had some issues with the presented deckplans, 1 dTon to the deck square, there is a PDF on the Mongoose site correcting this.

Ship's lockers, in many of the other variants, are mentioned but not how many or how much volume they take up.

I have never considered the "Ship's Locker" to be a specific place, but rather the collective term for all the lockers and cabinets where stuff gets stored. As for it's volume that really isn't a issue, unless you want it to be one as most shops as designed have vast tracks of unused volume that is titular assigned to some larger equipment. Your average 1.5 meter wide corridor (5 feet wide) has plenty of room for wall lockers and such.

While a ship's locker designated for vacc suit storage and suit-up room might be a small 1-dtons.

This is one of the place my analogy can break down, but this is really driven by how much room you feel is needed for suit storage and associated room for donning. In my general estimation this is more a function of the types of suits used and the numbers of people who may need to suit up at the same time. With Battledress and Hardsuits needing dedicated space.

Everything in the locker is destroyed which usually includes vacc suits, weapons, and the items that can be used to repair damage. At minimum any ship, civilian or military, will have at least 1 ship's locker.

As there isn't a hard coded mechanic for this, I handle this with roleplaying conventions.

Passageways which is traditional seafaring speak for corridors or hallways are another item not very well defined in most of the Traveller design systems. Most of the design sequences state in some fashion that a standard 4-dton stateroom includes part of a ship's passageway. Unfortunately, they don't state how much of the stateroom's 4-dtons are used to make up corridor/passageway. Again going to the Scout/Seeker deckplans outside the 4 staterooms are 4-squares representing a passageway.

Ok this is one of the issues that causes much to and fro. In general the Lifesupport rating/volume in Traveller is expressed in Staterooms. But in reality this probably should be expressed as volume required per person. Looking at this in this light one person requires 4dTons which includes where the sleep, eat and take care of other biological necessities. So quarters are going to be variable. High Passengers and command officers generally have 2-2.5 dTons of personal cabin with personnel fresher devoted directly to them, crew and Mid passengers 1 to 1.5 dTons with shared fresher space (though this is up to the designer), junior Crew and steerage passengers, marines etc, with be 2 or more to the dTon. The overage from Quarters goes to passageways, galleys etc...

Now, going through the other spaces of the ship you have bridge, electronics, engineering spaces all give up some of their volume to access.

I reserve 10% of the engineering for stores and tool space. The drives them selves occupy only half to two thirds of the remaining volume for the drives themselves with the remaining volume used as access space.

Do the 4 squares represent 4 or 8-dtons of volume?

4 squares should be 2 dTons, under the MgT parlance.

I'd like to recommend the following
For a standard 3-person in vacc suit airlock be 0.5-dtons.

I can go with that.

 

[snrdg121408]

Hello brionl,

On one level I agree with your suggestion. However, I've actually had to learn the basics of architecual drawing and blueprints. The instructor stressed that the drawings really need to reflect the real world product. Traveller deckplans are blueprints and the 20% slop factor would have gotten points taken off. Thanks for the reply.

My advice would be to not worry so much about it. Just pick a shape that is approx. the right size and draw in stuff that looks good.

 

[snrdg121408]

Howdy AndrewW,

Thank you for the reply and comments. The major cause for deckplan overage is from all the little items that don't take up volume. If a component is on the deckplan then the item takes up volume which ultimately reduces cargo space.

I have to agree with you. It would be nice for deckplans if all this could be worked out. Ship's lockers take up space on the deckplans, but no tonnage (just as one example). This makes plans not match up to the listed tonnage. Not to mention that some of the official deckplans don't match up tonnage wise to the used space.

 

[AndrewW]

Ok, in general there is a 20% slop factor, this has been standard assumption since CT.

Yes but that doesn't mean one has to agree with it...

 

[snrdg121408]

Hello Golan2072,

Good to hear from you again and thank you for your reply. If possible could you drop me an email to discuss the troops you created for me on the post titled "Is there an Army & Marine Table of Organization in MgT?"

I like your layout better than the ones on the boats, aka submarines, and the surface ship I was stationed on for the bridge. On the subs the closest fresher, aka head, for E6 and below was in berthing usually 2 decks down. E7 and officers heads were 1 deck down. The Simon Lake, AS33, was a sub tender with the closest head being located aft of the watertight doors leading to the bridge. Of course the CO had an at sea cabin next to the bridge that had the appropriate facilities.

Yep, I was referring mainly to the CT books as being vague on various items. However, in my opinion, every design sequence is vague on somethings which contribute to deckplans that don't correlate with the stated displacement tons.

Again thanks for the reply.

A few deckplanning guidelines I've used before (in CT, but are probably workable for MGT as well):

1) The bridge tonnage given in LBB2 includes more than simply the physical bridge itself. While the exact composition of this tonnage is not given in LBB2, deck plan design calls for a more precise definition. I suggest the following: 50% of the bridge tonnage would be the actual Bridge, with workstations and workspace for the command crew (Pilot, Navigator, Chief Engineer, Chief Gunner, and, in larger ships, also CO and XO); 25% would be communication arrays and avionics (to which the computer tonnage should contribute as well, see below); 12.5% would be the ship's airlock(s); and 12.5% would go to office space, a "ready room" and a fresher for the bridge and command crew.

2) LBB2 says that the Stateroom tonnage includes more than just the stateroom itself, but does not give concrete data on this subject. I suggest that the actual Stateroom (3x3x3 meters, includes a bed or a bunk bed, a desk and a fresher) will take 50% (2 dton per stateroom); 18.75% (0.75 dton per stateroom) should go to the ship's Galley and Medlab; 6.25% (0.25 dton per stateroom) should go to the Ship's Locker/Armory; 12.5% (0. 5 dton per stateroom) should go to Life Support; 6.25% (0.25 dton per stateroom) should go to landing gear/fuel scoops/docking equipment; and 6.25% (0.25 dton per stateroom) should go to Corridors/Passages.

 

[Golan2072]

I like your layout better than the ones on the boats, aka submarines, and the surface ship I was stationed on for the bridge. On the subs the closest fresher, aka head, for E6 and below was in berthing usually 2 decks down. E7 and officers heads were 1 deck down. The Simon Lake, AS33, was a sub tender with the closest head being located aft of the watertight doors leading to the bridge. Of course the CO had an at sea cabin next to the bridge that had the appropriate facilities.

If you want a more military feel to your Traveller starships, simply increase the part of life support equipment out of the stateroom tonnage, so that actual living space is actually 1 ton out of 4... And just add together all the staterooms into one or two "barracks" rooms with bunks, with the captain (and other ranking officers if you want) getting double the tonnage.

 

[AndrewW]

If you want a more military feel to your Traveller starships, simply increase the part of life support equipment out of the stateroom tonnage, so that actual living space is actually 1 ton out of 4... And just add together all the staterooms into one or two "barracks" rooms with bunks, with the captain (and other ranking officers if you want) getting double the tonnage.

There is a Barracks option in High Guard. And an Assault Barracks in Signs & Portents #57.

 

[snrdg121408]

Afternoon GypsyComent,

Thank you for your reply and comments. Also thanks for all the stuff I've stolen, er I mean barrowed from your posts on various forums over the years.

Changing the name of an existing componet to something else works since
a lab designated as a galley has a fixed volume that is represented on the deckplans and subtracted from the ships displacement. Airlocks take up space on the deckplans but take no volume from the ship's displacement. This is one of the reasons the deckplans don't match the design dispalcement.

Airlocks and ship's lockers are identified on the design worksheet at zero volume but are identified as taking volume on the deckplan. If 1 square equals 1-dton then a 1-square airlock equals 1-dton, the same applies to any ship's locker. Passageways are not listed but the deckplans show that in certain areas they take up squares. Which means volume is taken up equal to the number of squares used and decreases the ships cargo hold capacity. The Scout in MgT has a 10-dton Common area which includes space for accessing the Iris valve leading into the passageway across from the engineering space.

So I guess the best answer is that airlocks and ship's lockers require volume based on the number of squares used on the deckplans and as with every other identified component decreases a ships cargo capacity.

Again thanks for the reply which has given me a guage for doing my own deckplans.

Hard numbers are often not going to work very well. If the quarters, access and control areas of a deckplan are close to the aggregate tonnage available to staterooms and bridge, that's close enough. If you want a large and dedicated galley, buy a lab. That's what kitchens are, after all.

 

[snrdg121408]

Afternoon to you Infojunky,

Thank you for the link and comments to my post.

The 20% slop factor is what causes the deckplans from accurately representing the design displacement. Using the 20% slop factor a ship designed as 100-dtons can be shown as a 100 + (100 x .2) = 100 + 20 = 120-dton deckplan. I mentioned earlier that I had a very basic understanding of blueprints, aka deckplans, and archtecual drawing. If I had turned in a Traveller deckplan using the 20% slop factor the instructor would have nailed me to the wall, not to mention knocking of a lot of points.

Yep, I missed the TNE scale which is probably why my calculations for TNE deckplans were even more off than for any of the othe design systems. Thanks for the information. I agree that 1 dton is the same regardless of whether the volume is 14 m^3, 13.5 m^3, of 500 ft^3 and is used consistantly in the design. Unfortunately airlocks, ship's lockers, and passageways usually do not have defined amonunt of displacement tonnage.

Okay, I can handle the size of your standard airlock and a single person lock. Unfortunately, the dimensions don't match the scale show in my copy of MgT Core book for any of the designs. I also agree that the hatches associated with the cargo hold will be different.

Apparently, I have a first printing of the MgT core book. I'll have check out the pdfs soon.

Most people don't think in about ship's lockers which are in simplest terms the same thing as cargo holds. These cargo holds are peppered throughout ships and called damage control lockers, janitor closets, weapons lockers, or just about any name that is a place to store equipment not identified as cargo.

Again I agree that the size of a Ship's locker used to store vacc suits can be any size. A small ship carrying troops with Battle Armor would have a large ship's locker that would probably house both vacc suits and the armoe. Large ships could devote space for ship's locker or more accurately Battle Armor storage/repair bays or morgues. Same answer for the Hardsuits. Basically the ship's locker is a generic place holder that the Traveller party can find the items they need to get through the scenario designed by the GM. Of course the really evil GM will thwart the party with the item not being in the locker, in pieces, or broken but repairable. ;-)

True the damage tables usually skip damage to airlocks and ship's lockers, unfortunately many seasoned GMs usually rewrite the tables to include these two overlooked components. I know from experience how that works, which is one of the reasons why I design ships with a minimum of two each. Of course having back-ups doesn't mean the GM won't take delight is taking out as many as he can during combat or accident that comes along.

Yep, passageways in Traveller do cause, in my opinion, the major amount of deckplan overage. Architectural standards usually address passageways separately from staterooms. Also, a standard Traveller stateroom is a combination of sleeping, bathroom, eating, and living spaces. in an open floor plan. As mentioned in an earlier reply here I've come up with an idea to use a minimum of 1 square as passageway between staterooms. For me this appears to be the simplest solution.

As mentioned earlier the deckplans I have been looking at appear to be in a first printing of MGT and the 4 squares representing a Scout stateroom work out to be 1-dton per square.

Again thank you for the reply and comments.

First off, there is a Yahoo Group devoted to Deckplans, and a lot of these issues have been and are hashed out there.

One of the items that have always given me trouble in drawing Traveller deckplans centers around the volume of airlocks, ship's lockers, and passageways, aka corridors or hallways.

Ok, in general there is a 20% slop factor, this has been standard assumption since CT.

Volume in MgT as well as all the Traveller flavors is measured as 1 displacement ton, with two exceptions equals, 14 cubic meters of hydrogen. MT uses 13.5 cubic meters and GT uses 500 cubic feet. With the exception of GT, the scale of a deckplan uses 2 squares to represent 1 dton, which equals 1.5 meters wide by 3 meters long, and an overhead, ceiling for landlubbers, height of 3 meters.

You missed TNE which use 2 meter squares with a 3.5 meter deck height.

But, the exact volume you use really isn't a big issue as 14m^3 ≈ 13.5m^3 ≈ 500 cuft, as long as you are internally consistant.

Most of the flavors of Traveller state that a ship can have a maximum of 1 airlock per 100-dtons of hull but not how much volume the component takes up.

My standard lock is usually 4 squares (3 meter square) and personnel scale lock is 1 square (1.5 meter square) location is generally dictated by conformation of the ship. I try to keep a quarterdeck with lock at ground level for ships that land. And on the Main deck on ships that don't. With that engineering locks and cargo locks are placed as needed.

Cargo locks tend to be size to the amount and types of cargo transported. Frequently a hold will only have an outer door, with a standard lock leading from the hold to the rest of the interior of the ship.

Unfortunately, I'm not sure if the examples shown on the deckplans in the MgT if the airlocks are 1-dton or 0.5-dtons. The Scout/Seeker deckplans, like a majority of Traveller plans,

Which version of the TMB do you have? The initial release had some issues with the presented deckplans, 1 dTon to the deck square, there is a PDF on the Mongoose site correcting this.

Ship's lockers, in many of the other variants, are mentioned but not how many or how much volume they take up.

I have never considered the "Ship's Locker" to be a specific place, but rather the collective term for all the lockers and cabinets where stuff gets stored. As for it's volume that really isn't a issue, unless you want it to be one as most shops as designed have vast tracks of unused volume that is titular assigned to some larger equipment. Your average 1.5 meter wide corridor (5 feet wide) has plenty of room for wall lockers and such.

While a ship's locker designated for vacc suit storage and suit-up room might be a small 1-dtons.

This is one of the place my analogy can break down, but this is really driven by how much room you feel is needed for suit storage and associated room for donning. In my general estimation this is more a function of the types of suits used and the numbers of people who may need to suit up at the same time. With Battledress and Hardsuits needing dedicated space.

Everything in the locker is destroyed which usually includes vacc suits, weapons, and the items that can be used to repair damage. At minimum any ship, civilian or military, will have at least 1 ship's locker.

As there isn't a hard coded mechanic for this, I handle this with roleplaying conventions.

Passageways which is traditional seafaring speak for corridors or hallways are another item not very well defined in most of the Traveller design systems. Most of the design sequences state in some fashion that a standard 4-dton stateroom includes part of a ship's passageway. Unfortunately, they don't state how much of the stateroom's 4-dtons are used to make up corridor/passageway. Again going to the Scout/Seeker deckplans outside the 4 staterooms are 4-squares representing a passageway.

Ok this is one of the issues that causes much to and fro. In general the Lifesupport rating/volume in Traveller is expressed in Staterooms. But in reality this probably should be expressed as volume required per person. Looking at this in this light one person requires 4dTons which includes where the sleep, eat and take care of other biological necessities. So quarters are going to be variable. High Passengers and command officers generally have 2-2.5 dTons of personal cabin with personnel fresher devoted directly to them, crew and Mid passengers 1 to 1.5 dTons with shared fresher space (though this is up to the designer), junior Crew and steerage passengers, marines etc, with be 2 or more to the dTon. The overage from Quarters goes to passageways, galleys etc...

Now, going through the other spaces of the ship you have bridge, electronics, engineering spaces all give up some of their volume to access.

I reserve 10% of the engineering for stores and tool space. The drives them selves occupy only half to two thirds of the remaining volume for the drives themselves with the remaining volume used as access space.

Do the 4 squares represent 4 or 8-dtons of volume?

4 squares should be 2 dTons, under the MgT parlance.

I'd like to recommend the following
For a standard 3-person in vacc suit airlock be 0.5-dtons.

I can go with that.

 

[GypsyComet]

In past editions the machinery that ran an airlock was given at 3 cubic meters, or slightly less than 0.25 dtons. The size of the actual airlock chamber is much less important to standardize.

The 20% slop factor was an attempt *in the rules* to prevent (or at least limit) the phenomenon observed in this thread: obsessive box counting. As a deckplan wonk from the 1977 edition of CT, I fully appreciate the free time gained and mental health I still have because I understood what that 20% statement was for. Not all of us are naval or aeronautic architects. Approximations ARE good enough as long as they fall within certain boundaries. The rules provide for 20% to be that boundary.

On top of the approximations of the deckplan step, there are also the obvious but (usually) unwritten approximations and get-you-bys inherent in the ship design process. Some of that has already been addressed in this thread, in that the "Bridge" tonnage is for *all* command and control, not just the room you drive from, and the stateroom tonnage is an approximation of volume it takes to support a passenger, not just the room he sleeps in. This approximation is unevenly represented in the rules, to be certain, and as unevenly understood by gamers, but it IS there.

If you are actually playing the game, my advice is to focus more on how the PCs interact with their ship than trying to recover those last 5.75 cubic meters. Ergonomic concerns are often forgotten in ship design, but your PCs will thank or curse you far more based on what it takes to get coffee (or a gun) during 3rd watch than making sure the fuel tanks are exactly the right size.

 

[AndrewW]

Again I agree that the size of a Ship's locker used to store vacc suits can be any size. A small ship carrying troops with Battle Armor would have a large ship's locker that would probably house both vacc suits and the armoe. Large ships could devote space for ship's locker or more accurately Battle Armor storage/repair bays or morgues. Same answer for the Hardsuits. Basically the ship's locker is a generic place holder that the Traveller party can find the items they need to get through the scenario designed by the GM. Of course the really evil GM will thwart the party with the item not being in the locker, in pieces, or broken but repairable. ;-)

High Guard does have an Armoury supply some of this need. 2 tons for the basic one supporting up to 50 crew or 10 marines (for military vessels) . Of course multiplies may be needed or a larger version.

 

[barasawa]

As many people have pointed out, there has always been an accepted 20% fudge factor on ship layouts. If you need to rationalize it, some geometries are more efficient than other, and a more skilled naval architect will be able to squeeze out a bit more space where he wants it with the same raw resources.

Second, take a look at the T4 book, Marc Miller's Traveller - Naval Architect Manual. I don't know what scale those squares are at, but it still gives you a good idea of possible layouts of components.

As to some of the standard items that weren't given size ratings. Very simply, you don't have to worry about it, it's already included in the hull by default. (Part of that 20% FF mentioned earlier.) If you want something to back that up, read the section on fuel scoops on page 117. They specifically state that adding it to a ship doesn't take up any tonnage. Obviously something is being either welded on or rebuilt to be scoops, so it is taking some kind of tonnage. Doesn't matter to you since it's already accounted for in the rules. You never see it, you don't have to worry about it, but it's still there.

One more point on that last bit, in High Guard page 61, it talks about adding airlocks to small craft.

Unlike starships, a small craft does not have an airlock by default.

This obviously implies that you don't have to take space for an airlock on a spaceship, just put the sucker in you floorplan and don't worry about it.

 

[snrdg121408]

Evening GypsyComet,

Is obessive box counting like bean counting? One of my characters is an obessive bean counter. I realize that most of Traveller fans that are gearheads are not, myself, professional architects that can whip out an accurate deckplan. At the same time a handwaving away the space used by components is not right either. Fine do not have a fixed standard for an airlock, ship's locker, or passageway but when the component is placed on the plan subtract the volume from the cargo capacity. There is a lot of slop factor left when adding the exterior hull form around the fixed components making up the hulls interior.

I've had players curse me for having deckplans that had the slop factor included. Any space that the players are most likely going access are the areas I more concerned with. A submarine is basically a starship and I'm very familiar with how the deckplans reflect the reality. So I guess I have to admit to being an obsessive box counter.

I'm beginning to think that my best bet is just do the text and totally forget about deckplans.

Anyway thanks again for the input even if we don't totally agree.

Respectfully

In past editions the machinery that ran an airlock was given at 3 cubic meters, or slightly less than 0.25 dtons. The size of the actual airlock chamber is much less important to standardize.

The 20% slop factor was an attempt *in the rules* to prevent (or at least limit) the phenomenon observed in this thread: obsessive box counting. As a deckplan wonk from the 1977 edition of CT, I fully appreciate the free time gained and mental health I still have because I understood what that 20% statement was for. Not all of us are naval or aeronautic architects. Approximations ARE good enough as long as they fall within certain boundaries. The rules provide for 20% to be that boundary.

On top of the approximations of the deckplan step, there are also the obvious but (usually) unwritten approximations and get-you-bys inherent in the ship design process. Some of that has already been addressed in this thread, in that the "Bridge" tonnage is for *all* command and control, not just the room you drive from, and the stateroom tonnage is an approximation of volume it takes to support a passenger, not just the room he sleeps in. This approximation is unevenly represented in the rules, to be certain, and as unevenly understood by gamers, but it IS there.

If you are actually playing the game, my advice is to focus more on how the PCs interact with their ship than trying to recover those last 5.75 cubic meters. Ergonomic concerns are often forgotten in ship design, but your PCs will thank or curse you far more based on what it takes to get coffee (or a gun) during 3rd watch than making sure the fuel tanks are exactly the right size.

 

[snrdg121408]

Evening barasawa,

Thank you for the reply and comments. I have never really accepted the maximum of 20% slop factor. I'll agree that there is going to be some volume differences between the design displacement and the deckplan, but 20% is a bit much. If the factor was smaller I'd probably not have started the post about Airlocks/ship's lockers & corridors/passageways.

I've got the T4 Book D Naval Architects Manual and have used the book as a reference. Yep, they diagrams are good for ideas on layout even without knowing the scale. However, I very sure that even they have fallen in the 20% slop factor trap.

I'm sorry to disagree since each square or hexagon represents a certain amount of space measured in dtons. If the scale is 1 square being equal to 1-dton then an airlock shown on a deckplan using 1 square subtracts 1-dton from what eventually is cargo space. Same goes for a ship's locker, which is basically a cargo hold for a specific type of cargo. Passageways or corridors depending on there location takes up volume. In the Mgt Scout the 4-squares separating the staterooms subtract from the available cargo dtons. The two squares located in the Common Area linking the statrooms to the Iris valve leading towards Engineers are already accounted for as part of the common area.

I've not looked at the MgT HG design rules, but if what was quoted is true I have to disagree depending on the small craft's size. A 10-dton small craft probably does not have an airlock. A 90-dton small craft intended to dock with starships and spaceships will have to an airlock. This means IMMgTU I'll disregard the small craft airlock rule or incorporate the rule for starships and spacecraft. The rule does not make sense to me.

Again thank you for your comments they are appreciated.

As many people have pointed out, there has always been an accepted 20% fudge factor on ship layouts. If you need to rationalize it, some geometries are more efficient than other, and a more skilled naval architect will be able to squeeze out a bit more space where he wants it with the same raw resources.

Second, take a look at the T4 book, Marc Miller's Traveller - Naval Architect Manual. I don't know what scale those squares are at, but it still gives you a good idea of possible layouts of components.

As to some of the standard items that weren't given size ratings. Very simply, you don't have to worry about it, it's already included in the hull by default. (Part of that 20% FF mentioned earlier.) If you want something to back that up, read the section on fuel scoops on page 117. They specifically state that adding it to a ship doesn't take up any tonnage. Obviously something is being either welded on or rebuilt to be scoops, so it is taking some kind of tonnage. Doesn't matter to you since it's already accounted for in the rules. You never see it, you don't have to worry about it, but it's still there.

One more point on that last bit, in High Guard page 61, it talks about adding airlocks to small craft.

Unlike starships, a small craft does not have an airlock by default.

This obviously implies that you don't have to take space for an airlock on a spaceship, just put the sucker in you floorplan and don't worry about it.

 

[GypsyComet]

Evening GypsyComet,

Is obsessive box counting like bean counting? One of my characters is an obessive bean counter. I realize that most of Traveller fans that are gearheads are not, myself, professional architects that can whip out an accurate deckplan. At the same time a handwaving away the space used by components is not right either. Fine do not have a fixed standard for an airlock, ship's locker, or passageway but when the component is placed on the plan subtract the volume from the cargo capacity. There is a lot of slop factor left when adding the exterior hull form around the fixed components making up the hulls interior.

You really need to go dig up a copy of MegaTraveller or TNE ship design, and leave the purposely abstract versions of ship design to the amateurs.

Setting hard standards for airlocks means you need to start outside the ship and look at the interstellar commerce model. What is being shipped, how it is being shipped, and what sort of facilities will be loading it into a ship's cargo capacity.

Traveller (in MT and TNE) set the size of the hardware that moves the air in and out of an airlock. The airlock chamber itself could be anywhere from a crawl lock (maybe 2.5 cubic meters, just enough to get a person through) to a "two-doored closet" (about half a dton, and fairly common on adventure class ships), to the five dton cargo container lock or something you can drive a 10 dton ATV through.

There are at least as many possible "standards" as there are things to load onto a ship. All of them share the air-moving hardware and two doors through a fully enclosing bulkhead, but otherwise...