Excel Ship Designer v2025.06.21

[Arkathan]

I'm working on breakaway hulls now (still), but will check the others to see if advanced formatting crept in.
External cargo is a bunch of containers slid into racks or frames or clamped on. They should not be available for fuel. Although you could put fuel in the containers and transfer it into the hull after several hours of fiddling, or with an unrep system.

 

[J. L. Brown]

I'm working on breakaway hulls now (still), but will check the others to see if advanced formatting crept in.
External cargo is a bunch of containers slid into racks or frames or clamped on. They should not be available for fuel. Although you could put fuel in the containers and transfer it into the hull after several hours of fiddling, or with an unrep system.

Lots of bulk-liquid cargos might be hauled externally, making a distinction between those and 'fuel' is a bit odd. Fuel in a collapsible tank already cannot be used by the Jump engine, it has to be pumped into regular fuel tankage first; that is a major restriction on the key function of fuel.

 

[Arkathan]

Bladders and mounted tanks are inside a cargo space and connect to the fuel system.
Fuel mounted outside that is ready to use is a designated as a drop tank. It also has the proper fuel connections for ready use. You do not have to drop drop tanks when they are empty.
Fuel in cargo containers clamped to the hull do not have connections to internal fuel lines. You would have to maneuver them to a cargo bay or air lock to access cargo container connectors or use an unrep system to access the fuel those external containers.
For the connectors, some versions of Traveller have had rigs that allow a ship with fuel scoops to attach/extend a hose for the purposes of melting ice and sucking up the water. Something similar could be done with external tanks, but the setup would be as labor intensive as ice mining.

 

[Terry Mixon]

Bladders and mounted tanks are inside a cargo space and connect to the fuel system.
Fuel mounted outside that is ready to use is a designated as a drop tank. It also has the proper fuel connections for ready use. You do not have to drop drop tanks when they are empty.
Fuel in cargo containers clamped to the hull do not have connections to internal fuel lines. You would have to maneuver them to a cargo bay or air lock to access cargo container connectors or use an unrep system to access the fuel those external containers.
For the connectors, some versions of Traveller have had rigs that allow a ship with fuel scoops to attach/extend a hose for the purposes of melting ice and sucking up the water. Something similar could be done with external tanks, but the setup would be as labor intensive as ice mining.

I think he intended to use them for external fuel storage from skimming that could then be moved to other ships via UNREP. He’ll have to clarify if I got it wrong.

 

[Arkathan]

I am getting odd behavior in OpenDocument. Any value in the 'Additional Tons of Fuel' throws an 'Invalid Value' error. Also, I am attempting to put extendable fuel bladders on a ship with External Cargo mounts and Interplanetary Cargo Nets -- but it seems as though the 'fuel' page does not recognize those as cargo space.

I will look to see if this happens in Sheets.... Yes, yes it does.

In GoogleSheets any value in the 'Additional Tons of Fuel' throws a data validation error.
"There was a problem
The data you entered in cell C11 violates the data validation rules set on this cell."

Also, external cargo apparently does not count as cargo space available for fuel. So apparently this is the same in both other spreadsheet programs. I do not have excel, so I cannot check it there.

Also -- is H23 on the Fuel tab supposed to calculate a dTonnage? I added a simple '=C23/100' to that cell, but it seemed blank before.

On both Sheets and OpenDoc, the Fuel tab cell C11 (the 'Additional Tons of Fuel' cell) apparently the validation rule expected a number between 0 and =B1048567. I deleted the 'B' at the beginning, and it worked fine. Added Cargo tab cells 'D11' and 'D12' to the error-detection stuff on the Fuel tab (cells 'T29' & 'T32'). Seems to work fine.

The Additional Tons of Fuel, in Excel, uses a validation of 0 to Cell I9 (India-9). That way it doesn't exceed the size of the hull.
Don't know what the conversion did with that or how to fix it in the future.

If anyone has any knowledge on this matter, let me know. Edit: If the other programs do not have a problem with names in validation, I could change it to Tonnage and get the same number.

H23 is intentionally blank. The tonnage is counted in the cargo section, because it must be mounted in a cargo bay, where it takes up cargo space, not additional ship space. Entering a number in H23 charges you for it twice.

For a fuel bladder in a net, an unrep system seems to be the appropriate transfer system.
If someone sees a better method that can be coded with the rules, let me know.

 

[Condottiere]

1. The reason you can't use fuel directly from a bladder to feed the jump drive, is, I'll speculate, because it sucks it too fast.

2. Fuel bladder, would tend to define it as a flexible container, in a net, which is also flexible; then, place those in unprotected acceleration.

3. In theory, if you have a large enough underway replenishment system, you can transfer within six minutes sufficient fuel from an external container to the starship for a jump.

 

[J. L. Brown]

I think he intended to use them for external fuel storage from skimming that could then be moved to other ships via UNREP. He’ll have to clarify if I got it wrong.

That is correct. A ship with Extrenal Cargo is 'Unstreamlined', but unstreamlined ships can still skim fuel.

Bladders and mounted tanks are inside a cargo space and connect to the fuel system.

External Cargo Space is still Cargo Space.

'Drop Tanks' can be used to power Jumps, and are essentially deluxe 'Mountable Tanks' with explosive quick-disconnects so that they can be emptied & dumped before a Jump. Ships using Drop Tanks can be (at best) Partially Streamlined. Clearly the best, to the point that some GMs just delete them from the setting; the most expensive option.

'Fuel / Cargo Conatiners' are kind of awesome. They can be used to Jump, are quick to swap between fuel or cargo, and cost one hundredth the price of Drop Tanks. Mounted in External Cargo, they increase the displacement tonnage of the ship; the ship is rendered 'Unstreamlined'; and each 20 dTons of capacity requires 1 dTon of dedicated space which is not otherwise usable. These are almost pure 'win' for Internal Cargo.

A 'Mountable Tank' in External Cargo Space can be used to Jump; but adds to the displacement tonnage of a ship during Jump, decreasing drive performance and increasing fuel use. Many would say that renders an External Mounted Tank somewhat pointless. It takes four weeks of work to add or remove, either way -- plus, having anything in External Cargo makes the ship Unstreamlined. A middle-ground choice, one five-hundredth the cost of Drop Tanks.

A 'Collapsible Fuel Tank' in External (or any, really) Cargo Space, cannot be used to fuel a Jump -- it must be transferred to a regular tank first; but only adds to the displacement tonnage of the ship while there is fuel in it. Like all the other fuel system options, no UNREP system is necessary; it is already connected to the fuel system -- an UNREP system would simply be useful for transferring fuel to another vessel. Clearly the worst choice, but has the advantage of (sometimes) freeing up some volume, and being one thousandth the cost of Drop Tanks.

(Funny -- lots of Classic ships carry Small Craft, and are assumed to be able to refuel them. No mention of UNREP or any other dedicated facilities though; I guess it was just a concept which was not considered).

 

[Arkathan]

Docking clamps and internal bays/docking space have the connections for fuel. There is the assumption that a docking clamp allows the crew to access the mother ship.

I have yet to find anything that allows external cargo to connect to interior systems via installed connections. If anyone can point to this reference, it would be helpful.

 

[Terry Mixon]

Docking clamps and internal bays/docking space have the connections for fuel.

Does it say that somewhere? I play it that was but would like it to be official.

 

[Arkathan]

HG'22 pg 52

EXTERNAL CARGO MOUNT
Instead of carrying cargo inside the hull, a ship can
be designed to mount cargo in an external rack or
framework. This allows a smaller hull to be used,
making the cost of transportation considerably cheaper.
Ships with streamlined or dispersed structure hull
configurations cannot use external cargo mounts. A
ship’s Thrust and jump capability must be recalculated
when using external cargo mounts, using the combined
tonnage of the ship and the external cargo it carries.
This likely means that the manoeuvre drive operates at
a lower Thrust and jump capability is reduced.
Cargo carried externally can only be accessed outside
the ship by vacc suit or vehicle.

Does it say that somewhere? I play it that was but would like it to be official.

The 400 ton lab ship used in Death Station and the example in HG'22
The Pinnace is attached with a docking clamp. There is an elevator/hall in the spoke and access between the two vessels. The Pinnace is modified with a fuel tank/purifier setup to provide wilderness refueling, but neither has an unrep system. The logical conclusion is that there are fuel/atmosphere connections and access to the mother ship included in a docking clamp.

In the next iteration, those may have to be purchased separately, but we shall see. For now, all we have to go on are the examples given. It is also possible that we currently have to pay for or use a free air lock for that purpose.

 

[Terry Mixon]

HG'22 pg 52



The 400 ton lab ship used in Death Station and the example in HG'22
The Pinnace is attached with a docking clamp. There is an elevator/hall in the spoke and access between the two vessels. The Pinnace is modified with a fuel tank/purifier setup to provide wilderness refueling, but neither has an unrep system. The logical conclusion is that there are fuel/atmosphere connections and access to the mother ship included in a docking clamp.

In the next iteration, those may have to be purchased separately, but we shall see. For now, all we have to go on are the examples given. It is also possible that we currently have to pay for or use a free air lock for that purpose.

I would sacrifice a free airlock for it. Thanks.

 

[Condottiere]

Use a firehose.

Run it through the catflap in the airlock hatch.

 

[J. L. Brown]

I have yet to find anything that allows external cargo to connect to interior systems via installed connections. If anyone can point to this reference, it would be helpful.

The various Fuel systems spell out what sort of connections are included with that type of fuel system. Their interaction with Cargo Space is just that they occupy it (or not). External Cargo was a johnny-come-lately, and all the interactions were not spelled out, nor (very likely) even thought through -- so it is no surprise that there is no specific 'ship Power can (or cannot) be run to External Cargo', nor 'Fuel can (or cannot) be run to External Cargo', nor 'Life Support can (or cannot) be run to External Cargo', nor 'Artificial Gravity can (or cannot) encompass External Cargo', nor 'Computer access or data services can (or cannot) be run to External Cargo'. There are cargoes where it might be reasonable to assert that any or all of those CAN be used with External Cargo, but the rules are (perhaps intentionally) vague.

If you feel strongly that all of the above are impossible, then please include a 'Allow/Disallow use of External Cargo' switch (defaults to 'Disallow') in the appropriate spot, so that folks who want to use External Cargo can do so by opting in.

 

[J. L. Brown]

The Additional Tons of Fuel, in Excel, uses a validation of 0 to Cell I9 (India-9). That way it doesn't exceed the size of the hull.
Don't know what the conversion did with that or how to fix it in the future.

H23 is intentionally blank. The tonnage is counted in the cargo section, because it must be mounted in a cargo bay, where it takes up cargo space, not additional ship space. Entering a number in H23 charges you for it twice.

On the Fuel tab in Google Sheets, cell India9 is blank. When I click on 'View More Cell Actions', then 'Data Validation' on cell C11 ('Additional Tons of Fuel') Sheets claims the only rule for that cell is 'Value between 0 and 1048567'; but it does not say where that rule is stored or established.

I am seeing an odd behavior; but H23 does not appear to count the dTons twice. =FIXED(C23/100,2,0) calculated the dTons for the empty bladder; the switched value on the Cargo section (D52) calls values from T28 & T29. T28 seems to be 'Installed but Empty' value; T29 is "='4-Fuel'!C200-1" which always returns '-1' because '4-Fuel'!C200 is blank.

Maybe calculate the tonnage of the empty bladder on '4-Fuel'!H23, since this tonnage will never change. Then add another row below 23, for 'Current dTons of Fuel in Bladder', which must be equal to or less than the maximum value (in H23). The '12-Cargo)!T28 value can then always be subtracted from total cargo volume, with a separate line for 'dTons of Fuel currently in the Bladder' -- this simplifies the 12-Cargo tab, by eliminating a drop-down menu, and puts the fuel-related calculations on the 4-Fuel tab.

 

[Arkathan]

Hmm, yeah, it should be I6, not i9. I don't remember moving those around, so not sure when that happened.
What should be happening in C23 when you toggle A23 is the message for "Requires Cargo Bay, No Piping to Jump Drive " fills with Yellow.
When you create a Cargo bay, tells you how much room you have to play with and fills the field with green.
Entering a number in C23 prior to creating a cargo bay reformats to an error message and displays //CFT>Cargo//.

OK, after digging while typing... Adding the Ramscoop tossed a shoe into the gears. That moved the validation field from I6 to I9, because C23 started at C20. Odd, because validation usually doesn't change when I move something.

I'll have to dig further to see what else broke.

 

[Arkathan]

The various Fuel systems spell out what sort of connections are included with that type of fuel system. Their interaction with Cargo Space is just that they occupy it (or not). External Cargo was a johnny-come-lately, and all the interactions were not spelled out, nor (very likely) even thought through -- so it is no surprise that there is no specific 'ship Power can (or cannot) be run to External Cargo', nor 'Fuel can (or cannot) be run to External Cargo', nor 'Life Support can (or cannot) be run to External Cargo', nor 'Artificial Gravity can (or cannot) encompass External Cargo', nor 'Computer access or data services can (or cannot) be run to External Cargo'. There are cargoes where it might be reasonable to assert that any or all of those CAN be used with External Cargo, but the rules are (perhaps intentionally) vague.

If you feel strongly that all of the above are impossible, then please include a 'Allow/Disallow use of External Cargo' switch (defaults to 'Disallow') in the appropriate spot, so that folks who want to use External Cargo can do so by opting in.

See HG'22 pg 52

Your out is to stick a small unrep system on the ship. Doesn't have to be big, and the fuel transfer won't take anywhere near as long as diving into a gas giant. That will let you circumvent the specified restrictions of requiring vehicles or vacc suits.
There is an article somewhere detailing self sufficient cargo containers, which allow sensitive cargo to be stacked externally.

I'll look at it more closely after I get that part of the sheet working as intended.

 

[mavikfelna]

I am testing out a Ship Designer in MS Excel for personal, non-commercial use.
If anyone wants to point out errors - politely - feel free to take a look.


Change log:
<snip>

Current Version: v2025.04.18

Apr 18 - Implemented rules for required steward levels in the Crew Tab
Automated adding required passenger storage in the Cargo Tab.
TM5 - Fixed error with entertainment section
change to passenger storage reporting
-a Passenger Storage goes away on Summary when = Zero.

Edit: Thanks to Another Dilbert, MingtheMirthless and DigrizJB for identifying bugs. Thanks to Terry Mixon for the formatting update and sensor correction, fabricators and help on craft tables

Hey, I love your sheet and it has helped me hugely. Terry Mixon has been helping me alot and he has recently posted his new robotic Low Berths and I was wondering if we could get some way to add these to the sheet? Even a line where we can enter a custom low berth config with TL, Price, Tonnage and Power?
Thanks!

 

[Terry Mixon]

Hey, I love your sheet and it has helped me hugely. Terry Mixon has been helping me alot and he has recently posted his new robotic Low Berths and I was wondering if we could get some way to add these to the sheet? Even a line where we can enter a custom low berth config with TL, Price, Tonnage and Power?
Thanks!

And number of occupants. I've literally gone nuts creating alternate low berths, alternate emergency low berths, and 3-person 1-ton cluster low berths. That was not on my dance card, but I'm glad someone finds them useful.

 

[mavikfelna]

And number of occupants. I've literally gone nuts creating alternate low berths, alternate emergency low berths, and 3-person 1-ton cluster low berths. That was not on my dance card, but I'm glad someone finds them useful.

yes, I forgot to add occupants. Thanks for adding that and for all your hard work on making such great toys to play with!

 

[Terry Mixon]

yes, I forgot to add occupants. Thanks for adding that and for all your hard work on making such great toys to play with!

You're welcome. Building robots, vehicles, and ships is fun.