Excel Ship Designer v2025.05.03d

[Arkathan]

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

I will add two custom lines to the crew and passenger section. These will report to the summary as user defined. You can use them for any type of accomodations that way.
There are more characteristics than are displayed, so the area to define custom accomodations will probably have to go at the bottom of the page, below the multi-environment section.
I won't get to it until after I finish getting the break away hulls fixed, and the fuel bladders.
I'm currently wrestling with the drives page, to figure out the best way to show two drives, built for varying tonnages and ratings, that combine to provide a rating on the combined ship, and then how to report that on the summary.

 

[Terry Mixon]

I will add two custom lines to the crew and passenger section. These will report to the summary as user defined. You can use them for any type of accomodations that way.
There are more characteristics than are displayed, so the area to define custom accomodations will probably have to go at the bottom of the page, below the multi-environment section.
I won't get to it until after I finish getting the break away hulls fixed, and the fuel bladders.
I'm currently wrestling with the drives page, to figure out the best way to show two drives, built for varying tonnages and ratings, that combine to provide a rating on the combined ship, and then how to report that on the summary.

That’s for all that. The ship was making my brain hurt trying to recreate it.

 

[mavikfelna]

I will add two custom lines to the crew and passenger section. These will report to the summary as user defined. You can use them for any type of accomodations that way.
There are more characteristics than are displayed, so the area to define custom accomodations will probably have to go at the bottom of the page, below the multi-environment section.
I won't get to it until after I finish getting the break away hulls fixed, and the fuel bladders.
I'm currently wrestling with the drives page, to figure out the best way to show two drives, built for varying tonnages and ratings, that combine to provide a rating on the combined ship, and then how to report that on the summary.

Thanks for that! So now I could even add the small 2 ton single staterooms from MT, which is great!

 

[Terry Mixon]

Thanks for that! So now I could even add the small 2 ton single staterooms from MT, which is great!

I wonder if it’s two (one for crew and one for passengers) or two each? I vote for two each because one might want small staterooms and special low berths at the same time.

 

[Arkathan]

I wonder if it’s two (one for crew and one for passengers) or two each? I vote for two each because one might want small staterooms and special low berths at the same time.

Two each.

 

[J. L. Brown]

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.

That is a very odd restriction. Fuel and Cargo are not the same thing; and there are no canon 'Fuel System Options' that I am aware of that explicitly state 'This is not in any way connected to the fuel system of the ship it is installed on. Install pumps and piping (at a volume, power, and credit cost) separately."

Getting to granny's antique fine china tea set in external cargo requires a vacc-suit; because it is cargo, not fuel. Getting a glass of delicious Frozen Concentrated Orange Juice from a bladder in External Cargo requires a vacc-suit; because it is cargo, not fuel. Getting a dewar full of liquid hydrogen from a (design unspecified) cargo container in External Cargo requires a vacc-suit; because it is cargo, not fuel.

Getting a dTon of hydrogen out of a 'Collapsible Fuel Tank' in External Cargo does not take a vacc-suit; it is fuel, NOT cargo. The bladder is attached to the fuel system of the ship by default. It is detailed (on page 48) in the section with the heading 'Fuel', not the section (page 52) with the heading 'Cargo'. The illustration of the bladder includes a connection to the fuel system of the ship (although, to be fair, it does not include the ship itself) as part of the bladder. The only interaction with 'cargo' in the fuel section is 'takes up cargo space' -- but it is not handled like cargo.

 

[Terry Mixon]

That is a very odd restriction. Fuel and Cargo are not the same thing; and there are no canon 'Fuel System Options' that I am aware of that explicitly state 'This is not in any way connected to the fuel system of the ship it is installed on. Install pumps and piping (at a volume, power, and credit cost) separately."

Getting to granny's antique fine china tea set in external cargo requires a vacc-suit; because it is cargo, not fuel. Getting a glass of delicious Frozen Concentrated Orange Juice from a bladder in External Cargo requires a vacc-suit; because it is cargo, not fuel. Getting a dewar full of liquid hydrogen from a (design unspecified) cargo container in External Cargo requires a vacc-suit; because it is cargo, not fuel.

Getting a dTon of hydrogen out of a 'Collapsable Fuel Tank' in External Cargo does not take a vacc-suit; it is fuel, NOT cargo. The bladder is attached to the fuel system of the ship by default. It is detailed (on page 48) in the section with the heading 'Fuel', not the section (page 52) with the heading 'Cargo'. The only interaction with 'cargo' in the fuel section is 'takes up cargo space' -- but it is not handled like cargo.

The problem I see with this is the rules assume it is inside the ship in the cargo section, not in external cargo.

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. When empty, collapsible tanks consume 1% of the tonnage they use when full.

Bolding mine.

That presumes the ability to run hoses to get the fuel from the bladder to the fuel tank. As exterior cargo, there is a pesky hull in the way and vacuum to deal with. Drop tanks make a hard connection to the fuel system in the docking clamp. In a more ad hoc setup, not so much.

 

[J. L. Brown]

Bolding mine.

Which highlights sloppy editting. It assumes that all cargo space available will be 'inside' a ship; 'External Cargo' is an afterthought. Notice that it is nowhere specified that the fuel inside the bladder is handled like Cargo.

That presumes the ability to run hoses to get the fuel from the bladder to the fuel tank. As exterior cargo, there is a pesky hull in the way and vacuum to deal with.

Fuel scoops and starports manage to get fuel from outside the ship to inside the ship with no trouble at all. Hulls have multitudes of places where wiring, conduits, piping, windows, and a host of other things pierce the hull without any problem at all. Getting from 'outside' to 'inside' is not some impossible task; especially as it is assumed that designers of ships make allowances for necessary functions. It is just as justifiable to assume that there are connections in appropriate places to allow taking on fuel; as it is that there are places (outside the usual design rules) for 'free' airlocks.

 

[Terry Mixon]

Which highlights sloppy editting. It assumes that all cargo space available will be 'inside' a ship; 'External Cargo' is an afterthought. Notice that it is nowhere specified that the fuel inside the bladder is handled like Cargo.



Fuel scoops and starports manage to get fuel from outside the ship to inside the ship with no trouble at all. Hulls have multitudes of places where wiring, conduits, piping, windows, and a host of other things pierce the hull without any problem at all. Getting from 'outside' to 'inside' is not some impossible task; especially as it is assumed that designers of ships make allowances for necessary functions. It is just as justifiable to assume that there are connections in appropriate places to allow taking on fuel; just like there are places (outside the usual design rules) for 'free' airlocks.

I believe that docking clamps should have air/power/fuel connections. There do need to be external fuel connections, I agree, but the rules as written don't favor something as ad hoc as a fuel bladder strapped outside the ship as a source of fuel.

I'm sure it could be rigged up, but the question in my mind is how durable a fuel bladder would be in that environment. External fuel tanks are not collapsible and presumably made sturdy. Something that can empty to 1% of its size is not sturdy at all and would be severely at risk of damage and having acceleration tear it apart without the support of those hard walls in a cargo bay.

I hear what you're saying but don't think the use of a collapsable bladder for external fuel storage--much less during fuel skimming if that is being considered--is practical.

 

[mavikfelna]

For an external bladder of fuel to be accessible from inside a ship, it would need to be a drop tank. Otherwise it has no plumbing.

 

[MasterGwydion]

I believe that docking clamps should have air/power/fuel connections. There do need to be external fuel connections, I agree, but the rules as written don't favor something as ad hoc as a fuel bladder strapped outside the ship as a source of fuel.

I'm sure it could be rigged up, but the question in my mind is how durable a fuel bladder would be in that environment. External fuel tanks are not collapsible and presumably made sturdy. Something that can empty to 1% of its size is not sturdy at all and would be severely at risk of damage and having acceleration tear it apart without the support of those hard walls in a cargo bay.

I hear what you're saying but don't think the use of a collapsable bladder for external fuel storage--much less during fuel skimming if that is being considered--is practical.

Not sure if this helps or not as it is non-Canon.

Fuelbag class Fuel Depot Drone
This ship was first created using Mongoose Traveller Second Edition rules. Ship stats are presented below.


Fuelbag class fuel depot drone, TL 12
Maintenance: 347 credits/month
Crew: none (virtual pilot)
MCr: 4.167
Excess power: 0
System____________________________________________________________tons__MCr____power
Planetoid hull (5 Hull)___________________________________________-10___0.04___2
Planetoid null space______________________________________________2_____0______0
Armor 2 (planetoid hull)__________________________________________0_____0______0
Budget thrust-1 maneuver drive for 100 tons (energy inefficient)__1_____1.5____13
Fusion power plant________________________________________________1_____1______-15
Collapsible fuel tank (can hold 600 tons)_________________________6_____0.003__0
External cargo mount (594 tons, to handle fuel tanks when full)___0_____0.594__0
Computer/5________________________________________________________0_____0.03___0
Basic sensors_____________________________________________________0_____0______0
Software: maneuver/0______________________________________________0_____0______0
Software: virtual crew/0__________________________________________0_____1______0

Fuelbag class Fuel Depot Drone/meta - Traveller

wiki.travellerrpg.com

 

[J. L. Brown]

For an external bladder of fuel to be accessible from inside a ship, it would need to be a drop tank. Otherwise it has no plumbing.

Plumbing is included; otherwise it is not a 'fuel tank'; it is a Cargo container which happens to be full of liquid hydrogen.

I believe that docking clamps should have air/power/fuel connections. There do need to be external fuel connections, I agree, but the rules as written don't favor something as ad hoc as a fuel bladder strapped outside the ship as a source of fuel.

Yes, they do. There is an option called 'External Cargo Mount', which includes special hardware for carrying & supporting things on the outside of the ship at potentially many Gs of acceleration.

There is also a 'Jump Net' which does the same thing; and the strangely mis-named 'Interplanetary Jump Net' (no Jump allowed!) at lower TL.

There are also a variety of options for installing Fuel tanks in Cargo Space. One of those options is a set of hardware for connecting a collapsible bladder for storing & using fuel.

Something that can empty to 1% of its size is not sturdy at all and would be severely at risk of damage and having acceleration tear it apart without the support of those hard walls in a cargo bay.

This is what the special support hardware for External Cargo is for. If you are carrying a bladder full of FCOJ in Exterior Cargo, then durability is not a problem -- because of the External Cargo hardware. A ship with such External Cargo can certainly maneuver & skim fuel without any additional hazard; the restrictions on External Cargo ships (and there are many) are spelled out in the definition of the External Cargo Mount.

 

[Terry Mixon]

Plumbing is included; otherwise it is not a 'fuel tank'; it is a Cargo container which happens to be full of liquid hydrogen.


Yes, they do. There is an option called 'External Cargo Mount', which includes special hardware for carrying & supporting things on the outside of the ship at potentially many Gs of acceleration.

There is also a 'Jump Net' which does the same thing; and the strangely mis-named 'Interplanetary Jump Net' (no Jump allowed!) at lower TL.

There are also a variety of options for installing Fuel tanks in Cargo Space. One of those options is a set of hardware for connecting a collapsible bladder for storing & using fuel.


This is what the special support hardware for External Cargo is for. If you are carrying a bladder full of FCOJ in Exterior Cargo, then durability is not a problem -- because of the External Cargo hardware. A ship with such External Cargo can certainly maneuver & skim fuel without any additional hazard; the restrictions on External Cargo ships (and there are many) are spelled out in the definition of the External Cargo Mount.

Okay, let's post the rules here.

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. Landing a ship with external cargo mounts is a dangerous procedure, so these ships can have difficulties trading at worlds without a shuttle fleet or highport. Landing a ship requires a Difficult (10+) Pilot check. Failure results in a Critical Hit to the cargo contained in the mount, with each point of negative Effect causing one level of severity, as described in the Critical Hit Effect chart on page 170 of the Traveller Core Rulebook. For example, a failed check with two points of negative Effect results in 1D x 10% of cargo destroyed.

External cargo can be jettisoned remotely. The mount is equipped with explosive bolts, allowing specific cargo to be released if necessary. A ship using external cargo mounts becomes unstreamlined regardless of its default configuration.

You've already wanted a deviation by saying the fuel should be accessible without going out. One could be a stickler for the rules and say that nothing in an external cargo mount can be accessed without going to get it in a vaccsuit. It is not designed to be handy.

The rules on the dangers of landing indicate how unstable the external cargo is. If landing risks destruction, then so does fuel skimming. There is nothing here that says otherwise.

Once again, a flexible, collapsable bladder isn't, in my view, suitable to take in for a landing or for skimming. It is inherently fragile. You can run those in your game however you like, but I can't imagine this working under the rules as written. Sorry.

 

[J. L. Brown]

Okay, let's post the rules here.

EXTERNAL CARGO MOUNT
{snip}

Cargo carried externally can only be accessed outside the ship by vacc suit or vehicle.

Landing a ship with external cargo mounts is a dangerous procedure, so these ships can have difficulties trading at worlds without a shuttle fleet or highport. Landing a ship requires a Difficult (10+) Pilot check. Failure results in a Critical Hit to the cargo contained in the mount, with each point of negative Effect causing one level of severity, as described in the Critical Hit Effect chart on page 170 of the Traveller Core Rulebook. For example, a failed check with two points of negative Effect results in 1D x 10% of cargo destroyed.

{snip}

Highlighting mine.

You've already wanted a deviation by saying the fuel should be accessible without going out.

No, there is no special deviation involved. A Collapsible Fuel Tank is already connected to a ship's fuel system. Please cite ANY exceptions where a 'Fuel System Option' is explicitly not so connected. As a Fuel system, handling Fuel, it obeys the rules for Fuel, not Cargo. You cannot scoop Fuel with a Cargo Net, nor move fuel around with a Cargo Crane or Loading Belt.

The 'special exception' is insisting that a Fuel system is fundamentally changed in how it works, and is intended to work, based on where it happens to be mounted.

The rules on the dangers of landing indicate how unstable the external cargo is. If landing risks destruction, then so does fuel skimming. There is nothing here that says otherwise.

Make up your mind. The rules specify exactly what the penalties for External Cargo are; and skimming fuel is NOT mentioned -- you are making that up. The penalties spelled out are for landing -- places where a ship is operating in close proximity to a solid surface, and perhaps other ships and structures, and might very well be within the tight confines of a landing bay. Skimming fuel happens in a wide open sky, where there nothing solid within a thousand kilometers of the hull; equating these is disingenous.

 

[Terry Mixon]

Highlighting mine.

No, there is not special dispensation involved. A Collapsible Fuel Tank is already connected to a ship's fuel system. Please cite ANY exceptions where a 'Fuel System Option' is explicitly not so connected. As a Fuel system, handling Fuel, it obeys the rules for Fuel, not Cargo. You cannot scoop Fuel with a Cargo Net, nor move fuel around with a Cargo Crane or Loading Belt.

I'm not trying difficult, but you are going outside the accepted use of the equipment. Nowhere does it mention collapsible fuel bladders going outside the ship. Also, there are also no rules that explicitly state that external fuel tanks are connected unless they are special cases like drop tanks.

Since you are looking to create something new, it is up to you to cite any rule explicitly stating they are connected when outside the ship in the external cargo area. It's not my place to disprove your assertion. It's yours to justify your new use of the equipment.

The 'special exception' is insisting that a Fuel system is fundamentally changed in how it works, and is intended to work, based on where it happens to be mounted.

I have seen nothing other than an UNREP system or drop tank that gets fuel into the ship when not undergoing fueling on the ground or in space, likely using an UNREP system equivalent. You want to make a change that isn't supported by the rules. Claiming that no rule says it can't be done isn't sufficient when you want to change something fundamental.

Make up your mind. The rules specify exactly what the penalties for External Cargo are; and skimming fuel is NOT mentioned -- you are making that up. The penalties spelled out are for landing -- places where a ship is operating in close proximity to a solid surface, and perhaps other ships and structures, and might very well be within the tight confines of a landing bay. Skimming fuel happens in a wide open sky, where there nothing solid within a thousand kilometers of the hull; equating these is disingenous. Pretending the rules specify 'skimming' when they do not is worse.

You mentioned this idea elsewhere while talking about fuel skimming using a drop tanker to refuel the fleet, so it's not disingenuous. This setup was your alternative to a fuel tanker I posted so I think it's fair to bring it up. Here it is.

Counter-offer:
Instead of internal fuel tank; fuel bladders, mounted externally. The external mounts take no space -- if you want them to occupy volume you could do them as 'Interplanetary Jump Nets'.
That gives you a 300000 dTon ship when skimming for fuel, and a 34000 dTon ship when empty -- delivering 266500 dTons of fuel. Of course, it will take about 11 hours to skim that much fuel, and about 5 hours to pump it off, so maybe having a fuel refinery aboard might make sense -- 20000 dTons should cover it. Plus the power-plant to run it. If you want an even 50000 dTons, the other 16000 could be 15200 capacity of fuel/cargo allowing the pelican to deliver other supplies (or just more fuel).

It's not only the structures that are a threat to a ship. Diving into atmosphere with an unbalanced and unprotected load is also a matter that has to be considered. A gas giant is a lot rougher than a planetary atmosphere, I suspect, so I feel it is something that has to be accounted for. A ship with a solid hull isn't a collapsable fuel bladder exposed to the gas giant's atmosphere during the scooping of fuel.

Honestly, this kind of thing will get a little warning sticker put on the bladder by the manufacturer to try and keep the next person from trying it.

You've said your case and that's fine. I disagree. No amount of arguing will change that. Do as you please.

 

[Arkathan]

You want to make a change that isn't supported by the rules. Claiming that no rule says it can't be done isn't sufficient when you want to change something fundamental.

Except that the external cargo rule says it cannot be done.

Can still do what you (broad you) want in your game.

For such an outlier, and in the absence of a rule to code in, change the summary to read what you (broad you again) want it to on that ship's sheet.

 

[J. L. Brown]

Except that the external cargo rule says it cannot be done.

It does not. It specifies that Cargo, when it is stored in an External Cargo Mount, is handled in a specific way. But a Collapsible Fuel Tank, when it is in any cargo area, does NOT handle the Fuel inside as Cargo; it handles it as Fuel.

For such an outlier, and in the absence of a rule to code in, change the summary to read what you (broad you again) want it to on that ship's sheet.

Does the sheet have room for Warp Drives?

 

[J. L. Brown]

It's not only the structures that are a threat to a ship. Diving into atmosphere with an unbalanced and unprotected load is also a matter that has to be considered. A gas giant is a lot rougher than a planetary atmosphere, I suspect, so I feel it is something that has to be accounted for. A ship with a solid hull isn't a collapsable fuel bladder exposed to the gas giant's atmosphere during the scooping of fuel.

All of that is covered by making the ship 'Unstreamlined', which is precisely what the rules already specify. A big bladder half full of FCOJ in the external cargo mount, or a bladder half-full of inert nitrogen gas, does NOT warrant anything further -- those are just Cargo. It seems like the big mental melt-down is over fuel and fueling; and it is entirely uncalled for.

The ship that installs External Cargo Mounts has Cargo Space, which happens to be outside the hull. It can be used for all sorts of things that other Cargo Space can be used for. Sometimes, things take up Cargo Space which have their own rules. They continue to obey those rules, despite being in Cargo Space.

 

[Terry Mixon]

All of that is covered by making the ship 'Unstreamlined', which is precisely what the rules already specify. A big bladder half full of FCOJ in the external cargo mount, or a bladder half-full of inert nitrogen gas, does NOT warrant anything further -- those are just Cargo. It seems like the big mental melt-down is over fuel and fueling; and it is entirely uncalled for.

The ship that installs External Cargo Mounts has Cargo Space, which happens to be outside the hull. It can be used for all sorts of things that other Cargo Space can be used for. Sometimes, things take up Cargo Space which have their own rules. They continue to obey those rules, despite being in Cargo Space.

Our disagreement is over whether that can include something as flexible as a bladder, and as fragile. You do you. So far as I'm concerned, this idea, while out of the box, is a no-go.

 

[Condottiere]

Internal and external, in relationship to the spacecraft, is relevant.

Internal would presume all the advantages of being inside the hull, including gravity, plumbing, life support, and inertial compensation.

External, would assume, by default, without the above, unless explicitly stated, and provided for.

Especially, inertial compensation, which is is only vaguely defined, and we don't know how far the field extends, and life support, without which, those Alaskan King Crabs are likely to go bad.