Arkathan
Emperor Mongoose
The book has rules for warp drives, and the alternate TL for Warp and hyperdrives.
The rule for external fuel tanks with included piping is called a drop tank.
Excel Ship Designer v2025.05.09
- Thread starter Arkathan
- Start date
The rule for external fuel tanks with included piping is called a drop tank.
J. L. Brown
Emperor Mongoose
You are the one claiming the Collapsible Fuel Tank is fragile. It is robust enough to contain liquid hydrogen at high pressures. Diamene disagrees : https://bigthink.com/hard-science/t...can-stop-bullets-by-hardening-like-a-diamond/
All I am asking for is support on the design sheet for a concept that other folks have already embraced and used. You run your own game how you want, and I will not say a word. I want this tool to be useful to me as well, to design ships I want to put into a game.
It is accounted for by buying an 'External Cargo Mount'. That is part of the ship architect's job, when laying down the original specification for the expected performance regimes the ship will work within.
If a GM wants to specify a special Cargo with exotic handling requirements, then that is part of designing an adventure -- not a ship.
J. L. Brown
Emperor Mongoose
The book has rules for putting Fuel systems of all sorts into Cargo Space. This is far less of an 'Outlier' than Warp Drives (or a hundred other marginal and obscure systems which have been added without an eyeblink) are. Nor is 'a note on the summary sheet' sufficient; the performance of the ship changes.
A Collapsible Fuel Tank in External Cargo volume is NOT a Drop Tank. It is much less useful, and far more restricted -- but it is cheaper. Allowing a simple 'Fuel in Collapsible Tank is in External Cargo Volume' toggle is not an insurmountable obstacle.
Condottiere
Emperor Mongoose
Sure, if the external container defaults at twenty five kilostarbux per tonne, plus energy source, than life support would be included.
And required to be paid for, specifically oxygen regeneration.
At fifty kilostarbux, default, per tonne, artificial gravity would be included.
And required to be paid for, specifically oxygen regeneration.
At fifty kilostarbux, default, per tonne, artificial gravity would be included.
J. L. Brown
Emperor Mongoose
That is the purvue of the person designing the container. The External Cargo Mount provides sufficient protection, support, and systems access that Cargo may be routinely stowed and hauled in the External Cargo Space. The Collapsible Fuel Tank includes sufficient machinery to function, even in areas where the hull does not provide gravity or life support -- or else those requirements would be specified in the rules already.
Condottiere
Emperor Mongoose
Outside of reinforcing rings to attach the hoses, like vacuum packs for clothing, I sort of doubt that those latex condoms have additional attachments.
MasterGwydion
Emperor Mongoose
High Guard page 48, and I quote,
"COLLAPSIBLE FUEL TANK Collapsible fuel tanks (also called fuel bladders) are large flexible bladders that expand when filled with liquid-hydrogen fuel. They take up cargo space in a ship and are used to extend range without the need to fit mountable or drop tanks. Fuel cannot be pumped directly from these tanks to the jump drive, so a ship must complete a jump before it can use fuel stored in collapsible tanks."
Bolding Mine. Argument over. It clearly states that Collapsible Fuel Tanks can only be used in cargo space in a ship. "in" being the important word there. In, as inside, not outside of the ship.
Terry Mixon
Emperor Mongoose
Have fun storming the castle.
Condottiere
Emperor Mongoose
1. To be fair, I have considered using fuel bladders externally.
2. Unsupported, acceleration above a certain point is going to pop them like a pimple.
3. They aren't self sealing, so the odds of getting punctured are there.
4. You could place them in an external cage/cargo mount, for some form of support.
5. An external net, by definition, is flexible.
6. No idea what the reaction of a jump bubble and a fuel bladder would be like.
7. I suppose, you could add that sealing goop we have for tires, since internal pressure would eventually bring it to the created leak.
2. Unsupported, acceleration above a certain point is going to pop them like a pimple.
3. They aren't self sealing, so the odds of getting punctured are there.
4. You could place them in an external cage/cargo mount, for some form of support.
5. An external net, by definition, is flexible.
6. No idea what the reaction of a jump bubble and a fuel bladder would be like.
7. I suppose, you could add that sealing goop we have for tires, since internal pressure would eventually bring it to the created leak.
Arkathan
Emperor Mongoose
Here is a compromise that does not effect the rules:
I have added labels to labs, craft bays, cargo bays and airlocks.
I can add labels to external cargo. Probably three lines, with a tonnage block after them. It will not count against the hull, and will throw an error if it exceeds total external cargo capacity. I'll even add in a user defined cost box, for giggles. Those label plates can be expensive...
In this way, you can have whatever you like in the external cargo and it will show up on the summary in the Cargo section.
So if you label one section of external cargo as "External Fuel Bladder with Piping" and enter the cost of a mountable tank/fuel bladder, no one can complain... as long as you don't try to pass it off as HG'22 standard.
I have added labels to labs, craft bays, cargo bays and airlocks.
I can add labels to external cargo. Probably three lines, with a tonnage block after them. It will not count against the hull, and will throw an error if it exceeds total external cargo capacity. I'll even add in a user defined cost box, for giggles. Those label plates can be expensive...
In this way, you can have whatever you like in the external cargo and it will show up on the summary in the Cargo section.
So if you label one section of external cargo as "External Fuel Bladder with Piping" and enter the cost of a mountable tank/fuel bladder, no one can complain... as long as you don't try to pass it off as HG'22 standard.
J. L. Brown
Emperor Mongoose
Yes, the bolding is yours; and all it does is illustrate sloppy editing. The unspoken assumption is 'All Cargo Space Is Inside A Ship', with External Cargo being completely overlooked. External Cargo is an afterthought, and I cannot think of a published canon ship that uses it -- and any that does is a member of a tiny minority. It is a bit like 'Battle Riders' being utterly ignored in the published fleets; there are a couple designs, but the vast majority of fleets are utterly conventional.
What that quoted rule does NOT do is state that a Collapsible Fuel Tank requires an UNREP system. Nor does it really define what 'In' a ship means when it is possible to stow and carry cargo outside the hull, but inside the volume affected by the drives.
You are not the only one. There are other folks designing ships with external bladders; there was one example up-thread.
The 'bladders are delicate, fragile things' is an assumption which is not stated in the rules. We know for certain that they are tough enough to contain high-pressure liquid Hydrogen for weeks. As you point out, the 'External Cargo Mount' is all about providing support which makes carrying cargo outside routinely possible -- and some of those unspecified cargoes might very well be in (potentially partially-filled) flexible containers.
This is true -- a Jump Net and an Interplanetary Jump Net also provide for carrying External Cargo. Using a Collapsible Fuel Tank with Jump is not possible; the fuel must first be pumped to other (Jump-compatible) fuel tankage. If someone put a Collapsible Fuel Tank inside a Jump Net, and made a Jump (using fuel from some other, non-bladder, source) then the Collapsible Fuel Tank and the fuel inside it would presumable still be there when the ship emerged -- that is the whole point of the Jump Net.
Jump fuel tanks are already assumed to be self-sealing; although a bladder might be less-good at this sort of thing, The rules do not specify. I would hesitate to add contaminants to my refined fuel.
Arkathan
Emperor Mongoose
A bladder in a Jump Net would be supported and do just fine in jump space. External cargo also does just fine.
It's the micro meteors I worry about. Much more powerful than a standard bullet.
Also no connectors, because twisting at every change in dV.
MasterGwydion
Emperor Mongoose
On a ship
Both "on a ship" and "in a ship" are correct, but they are used in different contexts. "On a ship" is used when referring to being physically on the deck or surface of a ship. "In a ship" is used when talking about being inside the ship's structure.By nautical terminology, which is in use on spaceships, such as the word hull, in a ship means inside the structure of the ship.
- Definition of external
- adjective
happening or arising or located outside or beyond some limits or especially surface
“the external auditory canal”
“external pressures”
synonyms:
outer
being on or toward the outside of the body
outside
originating or belonging beyond some bounds:"the outside world"
outside
relating to or being on or near the outer side or limit
see more
Seems pretty clear to me.
- adjective
MasterGwydion
Emperor Mongoose
Also, External Cargo Mount is on page 52 of High Guard '22.
So, your statement that all cargo is assumed to be internal is proved invalid by the mere existence of an External Cargo Mount. Since they exist, cargo must be able to be carried outside of the ship. Since the writers of the book knew that this was possible (they wrote it after all), it would be odd, to say the least, that they assumed that cargo could only be carried internally.
So, your statement that all cargo is assumed to be internal is proved invalid by the mere existence of an External Cargo Mount. Since they exist, cargo must be able to be carried outside of the ship. Since the writers of the book knew that this was possible (they wrote it after all), it would be odd, to say the least, that they assumed that cargo could only be carried internally.
Condottiere
Emperor Mongoose
Let's separate two issues:
Jump nets are a legacy before jump bubbles, and essentially are an extension of the lanthanum grid; I don't think we currently have, or use them.
Fuel bladders are likely manufactured from a material that can contain refined fuel; to be fair, if it's like a wineskin, it doesn't expand, but inflates and deflates.
Nothing says that you can't attach them externally, like you could with a pet carrier on the top of a car.
However, we aren't sure of the consequences, just that it's likely that they aren't optimal.
If we tow it, or net it, guaranteed it won't have the protection of the inertial compensation field.
External cargo mount, that would depend on the configuration of the inertial compensation field.
Which we have no idea of.
I'm sure physics would tell us, at what point the acceleration force would cause the contents of the fuel bladder, to cause a leak, followed by catastrophic collapse.
We could give it a pass at acceleration factor/zero.
Jump nets are a legacy before jump bubbles, and essentially are an extension of the lanthanum grid; I don't think we currently have, or use them.
Fuel bladders are likely manufactured from a material that can contain refined fuel; to be fair, if it's like a wineskin, it doesn't expand, but inflates and deflates.
Nothing says that you can't attach them externally, like you could with a pet carrier on the top of a car.
However, we aren't sure of the consequences, just that it's likely that they aren't optimal.
If we tow it, or net it, guaranteed it won't have the protection of the inertial compensation field.
External cargo mount, that would depend on the configuration of the inertial compensation field.
Which we have no idea of.
I'm sure physics would tell us, at what point the acceleration force would cause the contents of the fuel bladder, to cause a leak, followed by catastrophic collapse.
We could give it a pass at acceleration factor/zero.
J. L. Brown
Emperor Mongoose
The real question here is:
Why is it that not allowing a person to design a ship this way in the tool a hill which is worth dying on?
And if we are playing silly amphiboly games on 'words in the rules', then I present:
So there are two interpretations:
1} External Cargo is exactly equivalent to Internal Cargo.
The other one is almost as silly as some of the 'definition arguments' which I have seen --
2} Any ship which has External Cargo may never have any Internal Cargo.
Why is it that not allowing a person to design a ship this way in the tool a hill which is worth dying on?
And if we are playing silly amphiboly games on 'words in the rules', then I present:
So there are two interpretations:
1} External Cargo is exactly equivalent to Internal Cargo.
The other one is almost as silly as some of the 'definition arguments' which I have seen --
2} Any ship which has External Cargo may never have any Internal Cargo.
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Terry Mixon
Emperor Mongoose
Because as design nerds we have an overwhelming aversion to letting a questionable rule call go by unchallenged?
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J. L. Brown
Emperor Mongoose
Yeah, that is why it is proposed as a select-able toggle which defaults to 'nope'.
J. L. Brown
Emperor Mongoose
Apparently. Does that allow the ship to have fuel in the External Cargo area? That affects endurance, and all the other non-Jump things that fuel figures into.
