Hi all,
I am coming to this conversation a bit late, but it has stimulated a lot of thought on my part. I started a separate thread on modules.
Hi, I have been working on a large 10,000 dTon modular freighter. The ship has a manoeuvre-1 drive (100 dTons), jump-2 drive (505 dTons), power plant (300 dTon), fuel (2000+30 dTon), bridge (60 dTons), crew and passenger areas, plus other misc items total 4,000 dTons. My design includes six...
forum.mongoosepublishing.com
Thanks to several other great posters, I refined my idea which I think is relevant here.
The concept of self-loading container-containers. Allow me to explain.
You build a large jump-capable
Cargo-Tender (like the Battle Tender). You put the jump drives and passenger staterooms in this "core." I designed a 4000-dTon version that can carry six 1000-dTon Cargo Riders.
You build a large sub-light only ship (I chose 1000 dTon). Equip it with the absolute MINIMUM needed to get to orbit. Build it a convenient shape without a lot of wasted space. I call it a
Cargo-Rider. You fill that ship with cargo at the starport or wherever you like. This means you can do things like remove the entire roof and load it from the top if you want.
When the Cargo-Tender arrives, the six Cargo-Riders detach and fly down to the starport to be unloaded.
I designed fuel tanker versions of the Cargo-Rider. They can fly up to the tender and refuel it in orbit.
The fresh, full, out-bound Cargo-Rider can be waiting on the ground or even in orbit. As soon as the tender is refuelled and the tankers detach, the out-bound Cargo-Riders can attach to the Cargo-Tender. Cargo can be turned around in just a few hours.
The ship can carry up to 1128 x 5-dTon cargo containers in 1G / 1 atmosphere shirt sleeve comfort.
It could also carry up to 5700 dTons of bulk cargo (grain, ore, etc), or 5640 dTons of fuel (also with the capability to scoop and purify it during the 7 day jump).
This idea scales easily. The
Hadrian Class Battle Rider is 50,000 dTons. It is theoretically possible to have similar sized Cargo-Riders.
You just need pairs of worlds that need that volume of cargo. Considering that here on Earth, there are dozens of container ships carrying 18,270 TEU.* That is the equivalent to 51,811 dTons of cargo. That is 9.2 times the volume of cargo in my proposed Cargo-Tender with six Cargo-Riders (carrying containers).
* TEU = Twenty Foot Equivalent Unit shipping container = 2.44m x 2.59m x 6.058m = 2.839 dTon (assuming 13.5m3 per dTon).
Looking at the volume of trade on Earth, imagine a high population world with ten times the Earth's population. You would need hundreds or thousands of ships like this per day.
Just a few thoughts.