Mating Airlocks to Cargo Hatches

What can I say, a design system based on real world units would solve a lot of issues...

see sig...

🫥 🐙 🫣
Or just clearly state that ship items are ship scale measured in dTons and other items are metric. Then optionally add for items that are non ship scale but often carried on ship for use by the crew their docking space dTons.

Since air/rafts are common items a few different models would be nice and they should be clearly defined unlike the current where way back in the early days they had a air/raft that was more of an air/delivery van and now more of an air/sedan but both supposedly taking the same docking space and that space being the air/delivery van metric docking space made ship scaled to dTons on a one to one basis.
 
Here's my thing. Why use displacement tons at all? Why not just use m3 for volume and 1,000kg (1 ton) for mass? Oh look! No more confusion. Easy, simple, and yet over 40 years and we still can't manage to do it right. Either use all real-world numbers and nomenclature, like m3 and metric tons, or use all made up numbers, like bandwidth
 
Many of the vehicles in the book are of limited use. If I ever find I need a galleon, I am happy I can work it out using the design rules rather than needing one pre-built as its stats are going to be irrelevant 99% of the time. I don't need all the vehicles that are already in the CRB.

A TL8 train on the other hand would be useful and would be pretty common on many worlds. but to be useful needs to be able to traverse long distances at a fair clip or ballistic shuttles will be more efficient.
 
🫥😜 Nah, rating everything in cubic metres and 1000kg tons, far too sensible.

Striker, MegaTraveller, Fire Fusion and Steel, Star Cruiser - it just didn't catch on.

Much better to have a displacement ton that is sometimes 14 and other times 13.5, subdivided into spaces, which are actually double what you think (but that is hidden away) and then it can all be subdivided again into slots that are supposed to be a certain size but the examples than ignore the scaling. Simples.😜🫥
 
An air raft doesn't have wheels or a drive train and is traditionally depicted as much flatter than a car. Traditionally it doesn't have a roof or much of a windscreen either (and frankly if it flipped over it would be a death trap. My car is just under 1.5m on from the ground to the top. That includes the 6" or so ground clearance. Two that were packed to conform to a space constrained environment (vs a weight constrained environment) could reasonably stack to fit in a 3m space (they wouldn't necessarily drive on).

In general that's correct, and I'm fine with air rafts being able to be packed into shipping crates more efficiently than they can be into a vehicle bay.

And sure. A vehicle bay can have any ceiling height, like a cargo bay, but most of them are shown being at normal deck height, so let's just stick with the deckplans we have.

We get back to the vehicle bay having to be considerably larger than the deckplan footprint of the vehicle in order to be useful, and there being a minimum ceiling clearance. My argument is basically that while the default Air Raft could be designed to stack two within a 2.5 height, getting in and out of that is pretty damn awkward. Practical ergonomics dictate that there has to be clearance for a person to open the door, get in and sit.

It's not just the windscreen that sits above the Air/Raft deck... it's the passenger heads and shoulders too.

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Actually, I'd go back to CT and just define ships by mass. You only need volume when drawing up deckplans anyway, and the "2 squares per ton" thing works fine as an average aproximation for metric tons anyway.
 
I just saw a Spartan armoured personnel carrier backing out of a container, which I rather suspect contradicts Vehicles shipped spacing.

The issue, in my mind, is more why an air/raft takes up four tonnes in the Scout/Courier.

In theory, you could attach it on the side of the hull, like a life raft.


ShipsBoats_Raft_Carley_002.jpg
 
In general that's correct, and I'm fine with air rafts being able to be packed into shipping crates more efficiently than they can be into a vehicle bay.

And sure. A vehicle bay can have any ceiling height, like a cargo bay, but most of them are shown being at normal deck height, so let's just stick with the deckplans we have.

We get back to the vehicle bay having to be considerably larger than the deckplan footprint of the vehicle in order to be useful, and there being a minimum ceiling clearance. My argument is basically that while the default Air Raft could be designed to stack two within a 2.5 height, getting in and out of that is pretty damn awkward. Practical ergonomics dictate that there has to be clearance for a person to open the door, get in and sit.

It's not just the windscreen that sits above the Air/Raft deck... it's the passenger heads and shoulders too.

View attachment 5474
It was shipping space that I was contesting. You don't need to board a vehicle that is being shipped and in reality we don't even need to crew it to unload it as it has autopilot and it can unload itself. That windscreen need not be fixed either and could retract or be removed when shipping.

HG p61 advises us that a docking space has "...barely enough room for crew and passengers to scramble aboard. Most repairs and maintenance require the craft to be launched first."

When in a vehicle space we already add 10% for personnel access and assume the normal deck height whether that be 3m or 2.5m. You certainly don't need more than 2m headspace. You don't need any space in front or behind the air raft for boarding access. We can assume it lifts straight up and out of an overhead hatch or drives out of a forward hatch that it can be hard up against. Any access space is to the sides (and possibly only one side). Half a metre or so is adequate. Very few car parking spaces in multi-story car parks are more than that and we all manage.

I also don't recall seeing any indication of deck height on a cargo bay in any of the books, generally we only have top down views on deck plans. I'd be happy to be corrected with a citation.

We infer a 2.5m height for accommodation as there is no depicted plumbing, life support etc. and it must go somewhere, but that is only to avoid considering it. Humans only need a few metres for sufficient headroom, even 2.5m is spacious. 1/2 DTon per square is just convention and the only way that makes sense with squares 1.5m on a side is if the deck height is 3m. The 4 DTon for a stateroom includes all the bits needed to accommodate a passenger. It is not 4Dtons of empty space.

Cargo doesn't need all that support and so each DTon can be empty space (it doesn't cost any more than fuel storage and that doesn't need decks). Cargo containers that are 3m high on the other hand require a 3m deck height (and probably somewhat more if we are actually expecting to manoeuvre that stuff around). Cargo holds traditionally only have decks where needed structurally.

We can stack containers several high, it is harder to stack people.
 
Some cargo bays are indeed multideck. The Subsidised Merchant is a common example. I was specifically sticking with the Air/Raft earlier, because there is a practical minimum ceiling height, and getting in and out of even a small vehicle is going to need that (call it 2m, which is headroom for a tall human or average Aslan). The smaller vehicles are going to be less efficient in terms of bay dimensions; and I'd distinguish between vehicles and small craft here. Small craft are often shown snugly mated to the ship in an open cavity (the Broadsword cutters are a prime example). Because the small craft is spaceworthy, this doesn't cause any big issues and you can set up an access point for when they are docked - you just open the ship hatch, open the craft hatch and board. That's not usually how a vehicle bay needs to work. Nor is it practical to move a vehicle out into space to repair it in most cases.
 
Some cargo bays are indeed multideck. The Subsidised Merchant is a common example. I was specifically sticking with the Air/Raft earlier, because there is a practical minimum ceiling height, and getting in and out of even a small vehicle is going to need that (call it 2m, which is headroom for a tall human or average Aslan). The smaller vehicles are going to be less efficient in terms of bay dimensions; and I'd distinguish between vehicles and small craft here. Small craft are often shown snugly mated to the ship in an open cavity (the Broadsword cutters are a prime example). Because the small craft is spaceworthy, this doesn't cause any big issues and you can set up an access point for when they are docked - you just open the ship hatch, open the craft hatch and board. That's not usually how a vehicle bay needs to work. Nor is it practical to move a vehicle out into space to repair it in most cases.
What you are describing with ships fitted snuggly into open cavities are not internal docking areas such as Docking Bays (10%), Full Hangars (200%), or Docking Facilities (300%). You seem to be more describing docking clamps. Or does Traveller have exterior clamps that allow you to keep your streamlining? Maybe in a book that I don't have?
 
What you are describing with ships fitted snuggly into open cavities are not internal docking areas such as Docking Bays (10%), Full Hangars (200%), or Docking Facilities (300%). You seem to be more describing docking clamps. Or does Traveller have exterior clamps that allow you to keep your streamlining? Maybe in a book that I don't have?
I'm pretty sure you have it:
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I remember I considered this some time back, but Traveller didn't have the mechanisms for it.

What's essential are the power source, gravitational modules, and controls.

You could collapse sides and the seating, and have an even thinner silhouette.

Or, have air bags for the side, like a dinghy.
 
Some cargo bays are indeed multideck. The Subsidised Merchant is a common example.
That is contra-indicated by the description:
"In fact, if its cargo bay doors were larger, the subsidised merchant could theoretically swallow a free trader whole."
HG p189
The Type P Corsair on p195
"is infamous for devouring 100 ton ships whole and delivering them to criminal starports for refurbishing into ships that cannot be identified as the originals."
I do not believe that any 100T ship is only 2.5m in overall height (since they are at least one deck high internally themselves.

MGT2 deck plans are not necessarily consistent with the description. The corsair for example has a 220 square docking space. that must equal 110 tons of open space and each square is shown as 1/2 DTon. It does not say that each square is 1.5m on a side (though that is the conventional size and is consistent with staterooms for example). They could for example be 1m on a side and the deck height for the corsair could be 7m. This would make the other compartments oddly shaped and likely impractical.
I was specifically sticking with the Air/Raft earlier, because there is a practical minimum ceiling height, and getting in and out of even a small vehicle is going to need that (call it 2m, which is headroom for a tall human or average Aslan). The smaller vehicles are going to be less efficient in terms of bay dimensions; and I'd distinguish between vehicles and small craft here.
Except the rules do not distinguish between small craft and vehicles. HG p61 has:
"This is an internal bay in which a smaller auxiliary ship or vehicle can dock."
Small craft are often shown snugly mated to the ship in an open cavity (the Broadsword cutters are a prime example). Because the small craft is spaceworthy, this doesn't cause any big issues and you can set up an access point for when they are docked - you just open the ship hatch, open the craft hatch and board.
The Mercenary Cruiser cutter wells are not actually docking spaces per the description in HG as they are external to the ship if we are to believe the deck plans. They would be better described as docking clamps. It would be far more efficient to use docking clamps as the cruiser isn't streamlined (ditto the laboratory ship). This is a prime exemplar of the need to use common sense as the mercenary cruiser pre-dates the introduction of docking clamps. Someone drew a "cool looking" ship and added the components available at the time that best matched that concept. They are also not shown on the graphic of the ship as being external (or indeed present).

The images are not blueprints, they are artists impressions and not necessarily to scale and as we have seen in other publications even if they were, size is somewhat fuzzy. Frankly the deck plans of the cruiser bear no relation to the supposed spherical shape of the ship. It looks like the ship should actually be cylindrical with bulge around deck 3. It looks like the walls of the ship have been omitted from most of the decks to save space, which isn't helpful.

The air raft is also space worthy (you just need vacc suits) and is explicitly described as being capable of reaching orbit. Things like the ATV are deemed to have an exterior hatch. Most other docking spaces are fully internal (with maybe just a bubble canopy or roller door separating them from space).
That's not usually how a vehicle bay needs to work. Nor is it practical to move a vehicle out into space to repair it in most cases.
In which case you need to allocate twice the volume as it requires a hangar. I'd be happy with a 4 DTon hangar for air rafts but that is not consistent with the RAW.
 
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That is contra-indicated by the description:
"In fact, if its cargo bay doors were larger, the subsidised merchant could theoretically swallow a free trader whole."
HG p189
The Type P Corsair on p195
"is infamous for devouring 100 ton ships whole and delivering them to criminal starports for refurbishing into ships that cannot be identified as the originals."
I do not believe that any 100T ship is only 2.5m in overall height (since they are at least one deck high internally themselves.
I think my comment was badly worded there and we are actually in agreement. When I said some cargo bays are multideck, i meant that they extend through several of the ships's normal deck levels, as one space. I certainly did not intend that to be taken as "those cargo areas comprise of distinct layered decks", which I can now see my wording might imply.
 
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