Mating Airlocks to Cargo Hatches

In any case, when it comes to drawing up deckplans there's a lot of leeway and common sense should be applied regarding access and the actual dimensions of the vehicle in question.
 
I always go by vehicle stat blocks not any other source
That is what I am talking about. Vehicle Handbook Update, page 95:

This is a eight Vehicle 'Space' light grav vehicle. 4 Vehicle 'Spaces' = 1 dTon; but it lists the 'Shipping Tonnage' as 4 dTons -- so 100% 'extra' space is already allocated, that is exactly what a Full Hangar requires. There is no need to add extra space.
 

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Because it is explicitly defined (well, as much as anything is 'explicitly defined') that way? 'Shipping Tonnage' is the amount of space it takes up aboard a (space)ship.

What else would it be?
It could just be the tons that it masses for shipment ON WORLD. Do you think that everything being shipped around a planet would have shipping weights in dTons? Tons seems to me to indicate just that - tons, as dTons means a specified volume.
 
A 4 TON item fits in just about any cargo hold as there would be few less than 1dTon and that fits 4 TONS quite nicely.

Check back into the early days of Traveller before Mongoose introduced dTons and the air/raft had the same shipping TONS as today. The air/raft didn't get bigger the ships did and the ship measurement changed to dTons and the air/raft was never changed.
 
A 4 TON item fits in just about any cargo hold as there would be few less than 1dTon and that fits 4 TONS quite nicely.

Check back into the early days of Traveller before Mongoose introduced dTons and the air/raft had the same shipping TONS as today. The air/raft didn't get bigger the ships did and the ship measurement changed to dTons and the air/raft was never changed.
Shipping size, not shipping weight. Clearly stated. Whatever was, this is what is.
 
A 4 TON item fits in just about any cargo hold as there would be few less than 1dTon and that fits 4 TONS quite nicely.

Check back into the early days of Traveller before Mongoose introduced dTons and the air/raft had the same shipping TONS as today. The air/raft didn't get bigger the ships did and the ship measurement changed to dTons and the air/raft was never changed.
/* sigh /* Mongoose did not invent the Displacement Ton; it goes back to (at least) the 1981 printing of High Guard under Game Designers Workshop. And if you want to fit an Air/Raft into a single dTon then you are going to need to ignore or revise numerous canon Mongoose designs of ships that carry Air/Rafts. Or, better yet, ask Gier -- the fellow who is currently writing the 'Vehicle Handbook Update' to replace the last 'Vehicle Handbook Update'.

Granted, I am arguing for something similar -- but I am advocating in favor of Mongoose fixing a scaling issue that they borked, not simply house-ruling around it.
 
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Pretty simple.

Also, CRB p.185:

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No doubling. The Shipping size statistic from the vehicle description IS the base dTonnage used for the vehicle bay requirements before the 10% overhead.

CRB vehicle entries don't actually list mass, although hull points can be taken as guide. More hull points suggests more mass.
 
That is what I am talking about. Vehicle Handbook Update, page 95:

This is a eight Vehicle 'Space' light grav vehicle. 4 Vehicle 'Spaces' = 1 dTon; but it lists the 'Shipping Tonnage' as 4 dTons -- so 100% 'extra' space is already allocated, that is exactly what a Full Hangar requires. There is no need to add extra space.
I don't pay attention to shipping tonnage as that isn't the vehicle volume
 
/* sigh /* Mongoose did not invent the Displacement Ton; it goes back to (at least) the 1981 printing of High Guard under Game Designers Workshop. And if you want to fit an Air/Raft into a single dTon then you are going to need to ignore or revise numerous canon Mongoose designs of ships that carry Air/Rafts.

So it goes back further than I thought BUT the air/raft goes back even further at being 4 tons.

As to ignoring canon design I understand the most recent CRB makes the bridge for 100 dTon ships to be 6 dTon so they invalidate some of their own. So having air/rafts not need a 5 dTon docking space isn't that big of an issue, you can just carry more than one or bigger air/rafts or be able to substitute something else. Or do the redesign for your campaign (which I would do anyhow as where the PCs would be is TL 11 peak).
 
Are people considering that things have internal and external dimensions?

Shipping tonnage has to take into account overall length, height and width. Unless the vehicle is literally a rectilinear box there is going to be waste space in the vehicle bay - this is most apparent with smaller vehicles that have heights which are substantially lower than the ceiling.

We went through this much earlier, but an air/raft that is 2.5m x 4m is going to need a space that's at least 2 x 3 deck squares. It won't matter that it has more than a metre of clearance to the ceiling... the whole of ship design is going to have that as a matter of course in most cases.

But the internal dimensions expressed in terms of spaces will be smaller than the outside dimensions, unless you're building a TARDIS.

The rule is that two vehicle spaces take up one shipping ton/dTon. That does NOT mean a vehicle space is half a dton in volume, but that it is no more than half a dton in volume. Usually, it would be a bit less because of internal and external dimensions.
 
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That old 4 ton Air/raft could carry 4 tons as well. It had a write up by the Judges Guild which gave its dimensions as 2m wide, 3m long and 2m high 12m^3 or about 1 dTon. The passenger version we see these days is even smaller but both have the same shipping tons?

Look at the current (most recent I've seen is the 2016) Air/raft (4 tons, hull 16) much less cargo (.25 tons), AFV (10 tons, hull 60). The AFV is 2.5 times the raft tons but nearly 4 times the hull. Odd the grav floater looks to be about 1/4 the size but is .5 tons and 2 hull or 1/8th the size. Usually smaller items have more waste in their shipping dimensions than the larger items.

These numbers are all as far as I can see NOT properly adjusted to dTons.

Now tell me what the SHIPPING volume in CRATES has to do with the volume used in a docking space? All that waste space in the crate adds to the room it needs OUT of the crate? Why does the smaller passenger Air/Raft take the same shipping volume of the old cargo Air/Raft? Does not compute.
 
The "shipping volume" as used by MGT2e22 is the base bay size required to carry the vehicle on a ship in dTons, per pp 137 and 185. It's not actually for putting them in shipping containers, though I guess it could be used for that.
 
Are people considering that things have internal and external dimensions?

Shipping tonnage has to take into account overall length, height and width. Unless the vehicle is literally a rectilinear box there is going to be waste space in the vehicle bay - this is most apparent with smaller vehicles that have heights which are substantially lower than the ceiling.

We went through this much earlier, but an air/raft that is 2.5m x 4m is going to need a space that's at least 2 x 3 deck squares. It won't matter that it has more than a metre of clearance to the ceiling... the whole of ship design is going to have that as a matter of course in most cases.

But the internal dimensions expressed in terms of spaces will be smaller than the outside dimensions, unless you're building a TARDIS.

The rule is that two vehicle spaces take up one shipping ton/dTon. That does NOT mean a vehicle space is half a dton in volume, but that it is no more than half a dton in volume. Usually, it would be a bit less because of internal and external dimensions.
And that rule is crap; and ought to be changed. It creates more problems than it solves /* gestures at conversation here so far /* and it is part of the reason vehicle and robot systems do not scale to each other (or to ships) in any rational manner.

The Vehicle rule allocating one passenger seat per 3500 liters is already full of hand-wavy 'padding'; and as much as I hate it, it is at least consistent with 'Acceleration Benches' in HGU p 50.

[Edit:] As a point of comparison, a brief reality check. The Boeing 747-400 had the largest passenger-volume cabin (975 cubic meters) of any airliner ever put into service. Some configurations maximized the number of seated (economy) passengers at 660 passengers. This was sufficient space for people to endure 12+ hour trans-pacific flights; AND it included space for overhead bins, under-seat carry-on baggage, aisles, lavatories, crew seating, safety equipment, and galleys. That works out to a (fairly miserable, except for short term) volume of less than 1328 liters per passenger. Ten passengers per dTon (1400 liters) in acceleration benches would be somewhat more luxurious; 'Standing room only' would pack in far more people. Troops packed into an military vehicle might get some additional volume for equipment, but you can be fairly certain that 'their comfort' is not a top priority of the vehicle-designers. [/Edit]
 
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You really wouldn’t have airlocks for most loading and unloading. A airlock as Matt has said it a hatch room hatch. Cargo hatch’s would be designed to like up with station hatches so no airlock required. A airlock would be the worse thing for unloading a ship since you have to move the cargo into the airlock close the inner than open the outer hatch. Airlocks are really meant for EVAs not anything else
 
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