Ship design. Size of units

[atpollard]

The grid helps with determining how much space each item takes when drawing things out.

A 1m grid for layout of spaces would work better, then apply the official 1.5 m grid as an underlay.

FWIW: NASA recommends roughly 1m corridors and hatches for crews in spacesuits.

 

[AndrewW]

A 1m grid for layout of spaces would work better, then apply the official 1.5 m grid as an underlay.

I don't see a 1m grid working any better then the usual 1.5m for laying things out.

 

[rust]

A 1m grid for layout of spaces would work better, then apply the official 1.5 m grid as an underlay.

I don't see a 1m grid working any better then the usual 1.5m for laying things out.

It is doubtless a matter of taste, but I usually start with a 50 cm grid, sim-
ply because 50 cm is a convenient width for a chair, double that for a nor-
mal workplace at a console, for a bed or for a corridor, and nine of the
50 cm squares fit nicely into one 1.5 meter square.

 

[far-trader]

FWIW: NASA recommends roughly 1m corridors and hatches for crews in spacesuits.

1.23m to be accurate. Again, add wall thickness and you are quite close to 1.5m. Close enough imo

Felt I should note it is the light clothed width for corridors above (and not hatches). And now I've had a chance to check for the EVA suit it's a bit bigger, 1.69m for corridors, with a note that (external?) hatches must be able to allow a suited person to pass (presumably 1.69m if round). Meaning Traveller is on the lean side with it's (gross dimension) 1.5m squares, but I've usually used 1.2m for hatches and (clear) corridor width as sufficient. Naturally I think 1m is too little for several reasons

 

[AndrewW]

I don't see a 1m grid working any better then the usual 1.5m for laying things out.

It is doubtless a matter of taste, but I usually start with a 50 cm grid, sim-
ply because 50 cm is a convenient width for a chair, double that for a nor-
mal workplace at a console, for a bed or for a corridor, and nine of the
50 cm squares fit nicely into one 1.5 meter square.

Yup, it'll certainly vary depending on the person which is fine.

 

[PFVA63]

I've never really had a problem with the 1.5m width passages either. for the most part I've come to use a width of about 4inches (~100mm) for internal bulkheads, which I assume should be about the minimum thickness to allow a 2in (50mm) thick sliding door to fit within. For external bulkheads I assume a bit more (maybe up to about 8in or 200mm) to account for structural stiffening, insulation, and the like.

As others have noted, it appears that NASA suggests about 1.23m (4ft) for a passage for someone wearing a space suit. As such, especially if you assume that a passageway in a spaceship may also have handrails and the like (for 0-G operations) then an assumed 1.5m overall for a passage seems OK to me.

Just for reference, I looked up a couple sets of drawings for USN and USCG vessels at this website http://www.hnsa.org/doc/plans/ind in Traveler.ex.htm and found that for the ships that I looked at a minimum passageway of about 0.9m was typical, though some passages were up to 1.5m.

The ships I choose to look at were a ~1000mt Coast Guard Cutter, and a 1770mt Destroyer Escort. Several years ago I plotted up data relating total enclosed volume for modern warships versus its hydrostatic displacement in metric tons, and found that for post WWII ships if you divided hydrostatic displacement in metric tons by 4m you would get a close estimate to enclosed volume in Traveller type dtons.

As such, the 1000mt Cutter would be roughly the same enclosed volume of a Traveler 250 dton ship, and the 1770mt ship might be closer to a 440 dton Traveler type ship. So, these ships don't seem too far out of the range of the type of ships that adventurers might encounter in Traveler.

So, overall I'd prefer 1.5m passageways, but if anyone wanted to use smaller ones, I don't think I'd recommend using anything less than 1.0m ones (ie, 0.9m for the passage and about 0.1m to account for structure, etc.)

Anyway, just some additional thoughts.

Regards

PF

 

[rust]

As others have noted, it appears that NASA suggests about 1.23m (4ft) for a passage for someone wearing a space suit.

Yep, but I would assume that future space suits would be a lot less bulky
than those currently in use by NASA. In fact, we would probably be able
to design less bulky ones right now, just look at this here:

http://news.nationalgeographic.com/news/2007/07/photogalleries/spacesuit-pictures/

Since this has been a serious research project by the MIT, I am almost
convinced that something much like it will be possible "on the next tech
level".

 

[AndrewW]

As others have noted, it appears that NASA suggests about 1.23m (4ft) for a passage for someone wearing a space suit.

Yep, but I would assume that future space suits would be a lot less bulky
than those currently in use by NASA. In fact, we would probably be able
to design less bulky ones right now, just look at this here:

But then when you add armour and the like to a suit...

 

[rust]

But then when you add armour and the like to a suit...

... it would still be a lot less bulky than a NASA-type suit with added ar-
mour.
If one expects a NASA-type suit with added armour to fit through a 1.5 m
corridor, I see no problem to expect a skintight suit with added armour
to fit through a 1 m corridor ?

 

[AndrewW]

But then when you add armour and the like to a suit...

... it would still be a lot less bulky than a NASA-type suit with added ar-
mour.
If one expects a NASA-type suit with added armour to fit through a 1.5 m
corridor, I see no problem to expect a skintight suit with added armour
to fit through a 1 m corridor ?

True would be less bulky then a NASA type suit, but didn't say a NASA type suit with added armour would fit through the corridor.

 

[rust]

Besides, I usually design a ship in a way that makes it impossible to
reach certain vital installations (especially the bridge) while wearing
heavy armour, especially battle dress and thelike. The sections whe-
re the crew members are likely to wear heavy gear, for example at
and around the airlocks, moonpools and thelike, are usually far more
roomy than the sections where such gear would be out of place. It
adds a bit of (in my view plausible) security without making the life
of the crew considerably more difficult.

 

[AndrewW]

Besides, I usually design a ship in a way that makes it impossible to
reach certain vital installations (especially the bridge) while wearing
heavy armour, especially battle dress and thelike. The sections whe-
re the crew members are likely to wear heavy gear, for example at
and around the airlocks, moonpools and thelike, are usually far more
roomy than the sections where such gear would be out of place. It
adds a bit of (in my view plausible) security without making the life
of the crew considerably more difficult.

I could see the upside but also a downside to that. Those boarding the ship may not use heavy armour to reach those areas but those defending the ship may have it, or others coming in later to retake the ship.

 

[PFVA63]

Besides, I usually design a ship in a way that makes it impossible to reach certain vital installations (especially the bridge) while wearing heavy armour, especially battle dress and thelike. The sections where the crew members are likely to wear heavy gear, for example at and around the airlocks, moonpools and thelike, are usually far more roomy than the sections where such gear would be out of place. It adds a bit of (in my view plausible) security without making the life of the crew considerably more difficult.

I could see the upside but also a downside to that. Those boarding the ship may not use heavy armour to reach those areas but those defending the ship may have it, or others coming in later to retake the ship.

I guess another thought, too, is whether that might preclude someone from donning a space suit while on the bridge (say if there is a hull breach) and then trying to escape, or vice-versa (say someone in a spacesuit/armor (like say an emergency paramilitary rescue patrol / equivalent to a mdoern day Coast Guard), etc is trying to make it to the bridge to help rescue the crew.

With regards to a previous comment regarding future spacesuits being smaller than what NASA currently uses, I guess the flip side to this that maybe should also be considered is the question of whether people (and/or other sentient beings) in the 57th century might not be bigger than current astronuats.

Anyway, just some additional thoughts.

Regards

PF

 

[rust]

I guess another thought, too, is whether that might preclude someone from donning a space suit while on the bridge (say if there is a hull breach) and then trying to escape, or vice-versa (say someone in a spacesuit/armor (like say an emergency paramilitary rescue patrol / equivalent to a mdoern day Coast Guard), etc is trying to make it to the bridge to help rescue the crew.

In my setting this would cause no problem, only combat units have any
armour equivalent (in protection and bulk) to battle dress, and even tho-
se units normally wear lighter skintight space suits that fit through all cor-
ridors.

 

[kristof65]

IMO, a lot of Traveller ships show poor design traits, especially among the military ones. Corridor size is among these.

FREX, while it might be both necessary for quick and efficient movement between the bridge and engineering, and necessary for BD equipped troops to have access to both those areas, it probably isn't important that BD equipped troops have quick and effecient movement between them. So the corridors providing the quick and efficient movement betwen the bridge and engineering would be narrow, while a much longer/slower and wider route would still allow access for BD equipped troops. So if the bridge is taken, the surviving bridge crew can hightail it engineering and hole up there long before the BD equipped attackers can get there.

In most of the official published plans, a BD equipped strike force could quite easily hold and take an important area such as the bridge, engineering, etc.

 

[rinku]

Worth mentioning at this point that the origin of the 1.5 metre corridoor was the grid size chosen for Snapshot.

It remains a reasonable size for the purpose (i.e. miniatures combat), but in terms of drawing up plans there's nothing preventing you regridding, or even ignoring the grid altogether (But if you *do* want to use the plans for mini combat, it's best to make the walls run along the grid). Dropping to a 1m grid would work, though.

Personally, I don't see the 1.5 standard as a major issue. Traveller ships *aren't* NASA ships, and you have to allow paying passengers more room than you would a military crew.

 

[AndrewW]

In most of the official published plans, a BD equipped strike force could quite easily hold and take an important area such as the bridge, engineering, etc.

Even without wider passageways this could be done, attacking forces don't have to use an airlock, a breaching tube for example can cut right through the hull, while not always desirable can be the best option at times.

 

[justacaveman]

Use breaching charges to make your own doorways through intervening rooms (like they do now).

You don't attack heavily defended areas head-on, you hold their attention while your buddies go around and get them from behind.

 

[rinku]

I'm a *little* wary of high explosive use in a pressurised spaceship (if it's unpressurised, no problem). It occurs to me that you're going to have to be VERY careful or you'll cause as much damage to yourself as the opposition. It's better to think of combat in a spaceship more like combat in an airliner or submarine than in a building or a surface ship.

Plus, you know, if you're trying to take the thing intact, then blowing gaping holes in bulkheads and rupturing seals may not be the smartest move. Especially if there's vital electronics in either compartment.

I'd think that most ship breaches are going to be done with cutting equipment, not breaching charges for this reason.

On the up side, flash/bang grenades probably work a bit better in a tin can...

 

[BP]

'Burn your way thru' using souped up Glue gun - ala Firefly