I sort of derailed my own thread (SDB's vs. Warships) getting off on the cargo discussion, so I figured I'd start a new one, if anything just to make it easier to search at a later date.
The cost of starships, like container ships and pretty much any other cargo ship today, is huge, and some would argue that it's exorbitant. In either case, it's all about the money, right? Cargo ships, unlike warships, need to be designed to operate economically as possible. And their related operations need to be similar - fast and efficient.
Up till about 40 years ago, most cargo in the world was transported pretty much like it had been since day 1 - jumbled together in a cargo hold. Oh, they tried to be smart about it, but there's only so much you can do with palletized cargo. Bulk cargo's, on the other hand, kind of went the opposite direction. Bulk cargo's (wheat, corn, soybeans, coal, ore, etc) are actually more efficiently transported in bulk, using specialized freighters. In much the same way, specialized rail cars were developed to transport specific cargo's. Now you see tank cars, hoppers, coil cars, and more beyond the original box car and flat car.
Then along came containers. It made loading and unloading a snap. Shippers could now sell shipping by the TEU (20' foot containers. The 'standard' shipping container for sea transport is the 40' container, which is actually 2 TEU's). No longer did you need an army of stevedores (who tended to strike a lot too). Cranes with a single person could unload a ship easily, 4-5 of them can unload a ship in about 12 hours. It takes longer to load them naturally, but no more than 24hrs (this does not include the amount of 'ground' time necessary to pre-stage the cargo, though this is not much different than the old fashioned way either).
There's a complete dearth of information in regards to how cargo is moved in the Traveller universe. At least as far as the official guides are. Nothing I've found to date tells you how the "Ag" planets manage to get their goods to the buyers. Obviously not everything moves by Free Trader, Far Trader or Subsidized Merchant. And the books allude to larger cargo ships, but that's about it. GURPS mentioned some LASH-style ships with 1k Dton pods that got moved around, but not much else.
Which is ok for a RPG game. Not many players and refs want to play "Let's Move that Grain", or at least that's a suspicion of mine. As I see it, the cargo ships will be something along the lines of container ships of today, except sealed better to protect against the vacuum of space. The containers themselves will come in all sizes and shapes to facilitate transport and handling of the cargo. Everything that can be containerized will be. Shipping liquids can be done through containers by putting the tank itself within a container-frame (just like they do today). Livestock, too, can be shipped that way (there's an example in Merchants). Smaller containers (10-120Dton) would be popular as they can be loaded in pretty much any freigther. Plus they make for handy distribution of the products once they hit dirtside. Transport and storage of the cargo also needs to be efficient to keep costs down. But there will be some larger containers that need to be constructed to transport larger, bulk cargo's. Since a) materials science will give you access to strong materials, and b) a lot of work will be done in zero-g, making a 400Dton container, for example, to transport smaller containers makes physical and economic sense. Then once the ship hits the unloading point it can unload a single larger container, and load a single large container instead of 40 10Dton containers. Lighters can then pick up the container for transport to the surface or to an orbital facility.
For the most part, since containers are standardized, the cost per transport ton will be the same for any product, with a few exceptions. Products that are hazardous would naturally be charged a higher rate due to the risk factor. Sensitive cargo, like live animals, might likewise have a higher rate attached to them due to extra risk and potentially extra work having to take place to care for the animals. But for the most part if you can seal it in a container and not have to worry about it, then everything should be shipped for the same rate.
The container's themselves would come in two classifications probably. Vacuum-rated, and non-vacuum rated. The TL would also probably come in two levels. A lower TL for the container itself means more worlds can build their own locally - a huge cost factor. Higher TL containers would probably be slightly more expensive, but feature things like vacuum-ratings, temperature, atmosphere and gravity controls, and more than few might have their own anti-grav system built in (though that might be a bit cost prohibitive). Today a shipping container, as opposed to say a tractor-trailer container, is able to withstand most handgun fire not utilizing armor-piercing bullets. Why? Because shipping containers have to withstand a great deal of stress and the ocean environment. They are pretty tough. Though unless you had the need, you wouldn't build a shipping container to withstand LMG, autocannon, gauss or laser rifle fire unless you were transporting high-security cargo.
I would suspect the cargo container to have standard dimensions so that any of the thousands of planets in the Imperium could take a container and put it on a truck, a train, a grav vehicle, etc. Plus there is all the cargo handling equipment that would also stand to benefit from standardization. And we all know the Imperium is big on standardization! That really just leaves the weight of the container. In zero-g weight is zero, but mass counts for something. We handle that through Dtons. On the ground, however, weight CAN be a factor. But unless you are running GURPS and take into account both mass and weight, you can probably just discard that for gaming purposes. Who cares if you have 10 Dtons of marshmellow's or lead? They both take up the same amount of cargo space, right?
The cost of starships, like container ships and pretty much any other cargo ship today, is huge, and some would argue that it's exorbitant. In either case, it's all about the money, right? Cargo ships, unlike warships, need to be designed to operate economically as possible. And their related operations need to be similar - fast and efficient.
Up till about 40 years ago, most cargo in the world was transported pretty much like it had been since day 1 - jumbled together in a cargo hold. Oh, they tried to be smart about it, but there's only so much you can do with palletized cargo. Bulk cargo's, on the other hand, kind of went the opposite direction. Bulk cargo's (wheat, corn, soybeans, coal, ore, etc) are actually more efficiently transported in bulk, using specialized freighters. In much the same way, specialized rail cars were developed to transport specific cargo's. Now you see tank cars, hoppers, coil cars, and more beyond the original box car and flat car.
Then along came containers. It made loading and unloading a snap. Shippers could now sell shipping by the TEU (20' foot containers. The 'standard' shipping container for sea transport is the 40' container, which is actually 2 TEU's). No longer did you need an army of stevedores (who tended to strike a lot too). Cranes with a single person could unload a ship easily, 4-5 of them can unload a ship in about 12 hours. It takes longer to load them naturally, but no more than 24hrs (this does not include the amount of 'ground' time necessary to pre-stage the cargo, though this is not much different than the old fashioned way either).
There's a complete dearth of information in regards to how cargo is moved in the Traveller universe. At least as far as the official guides are. Nothing I've found to date tells you how the "Ag" planets manage to get their goods to the buyers. Obviously not everything moves by Free Trader, Far Trader or Subsidized Merchant. And the books allude to larger cargo ships, but that's about it. GURPS mentioned some LASH-style ships with 1k Dton pods that got moved around, but not much else.
Which is ok for a RPG game. Not many players and refs want to play "Let's Move that Grain", or at least that's a suspicion of mine. As I see it, the cargo ships will be something along the lines of container ships of today, except sealed better to protect against the vacuum of space. The containers themselves will come in all sizes and shapes to facilitate transport and handling of the cargo. Everything that can be containerized will be. Shipping liquids can be done through containers by putting the tank itself within a container-frame (just like they do today). Livestock, too, can be shipped that way (there's an example in Merchants). Smaller containers (10-120Dton) would be popular as they can be loaded in pretty much any freigther. Plus they make for handy distribution of the products once they hit dirtside. Transport and storage of the cargo also needs to be efficient to keep costs down. But there will be some larger containers that need to be constructed to transport larger, bulk cargo's. Since a) materials science will give you access to strong materials, and b) a lot of work will be done in zero-g, making a 400Dton container, for example, to transport smaller containers makes physical and economic sense. Then once the ship hits the unloading point it can unload a single larger container, and load a single large container instead of 40 10Dton containers. Lighters can then pick up the container for transport to the surface or to an orbital facility.
For the most part, since containers are standardized, the cost per transport ton will be the same for any product, with a few exceptions. Products that are hazardous would naturally be charged a higher rate due to the risk factor. Sensitive cargo, like live animals, might likewise have a higher rate attached to them due to extra risk and potentially extra work having to take place to care for the animals. But for the most part if you can seal it in a container and not have to worry about it, then everything should be shipped for the same rate.
The container's themselves would come in two classifications probably. Vacuum-rated, and non-vacuum rated. The TL would also probably come in two levels. A lower TL for the container itself means more worlds can build their own locally - a huge cost factor. Higher TL containers would probably be slightly more expensive, but feature things like vacuum-ratings, temperature, atmosphere and gravity controls, and more than few might have their own anti-grav system built in (though that might be a bit cost prohibitive). Today a shipping container, as opposed to say a tractor-trailer container, is able to withstand most handgun fire not utilizing armor-piercing bullets. Why? Because shipping containers have to withstand a great deal of stress and the ocean environment. They are pretty tough. Though unless you had the need, you wouldn't build a shipping container to withstand LMG, autocannon, gauss or laser rifle fire unless you were transporting high-security cargo.
I would suspect the cargo container to have standard dimensions so that any of the thousands of planets in the Imperium could take a container and put it on a truck, a train, a grav vehicle, etc. Plus there is all the cargo handling equipment that would also stand to benefit from standardization. And we all know the Imperium is big on standardization! That really just leaves the weight of the container. In zero-g weight is zero, but mass counts for something. We handle that through Dtons. On the ground, however, weight CAN be a factor. But unless you are running GURPS and take into account both mass and weight, you can probably just discard that for gaming purposes. Who cares if you have 10 Dtons of marshmellow's or lead? They both take up the same amount of cargo space, right?