2000 J4 Drop Tank Cargo Hauler

[PsiTraveller]

With the Cargo hauler I am not sure I would have the ship skim anything, what with the external cargo mounts making the ship rather sensitive. I think the tanks would be filled by the tender ship and hooked into position once filled, or the tank conencted and then filled from a fueling ship.

The strength of the connection and use of the external Demountable tank that is removable would have to be sorted out if the removable tank idea was to be effective. Having your tank fall off while skimming is awkward, there is all that paperwork to do, plus the whole risk of explosion.

And we really have to settle on a name for the removable fuel tank.

 

[AnotherDilbert]

A ship using external cargo mounts will become unstreamlined.

A commercial ship has no time to waste on trips to a gas giant. If we have the infrastructure in place to retrieve and refurbish the used drop tanks, fuel can easily be provided.

 

[Chas]

Wondering for the standardized heavy commercial routes they'd use pilots or automated ships. There might be one person overseeing the whole operation in a system. I guess there might be economies in place in a highly populated sector here where humans are cheaper than smart computers.

 

[AnotherDilbert]

I hate to say this, but between Virtual Crew, some Astro-Mech Droids, and a Autodoc (if we carry passengers), all crew needs can be automated, thereby removing the need for staterooms and even the bridge.

This saves us 40 + 18 * 4 = 112 dT, giving us an additional 112 * 7000 = Cr 784000 income per jump. Since we are scheduled and don't have to wait and scramble to find freight we can jump more often than every 14 days, so we can make 35 - 40 jumps per year, making it an extra MCr ~30 per year.

And we get rid of the salaries and life-support costs, say an average salary Cr 3000 and life-support Cr 2000 = Cr 5000 per month per crew. 5000 * 12 * 18 = 1080000 ≈ MCr 1 per year.

So, although I would never admit this in public, it would be economically mandatory to get rid of the crew, Imperial regulations permitting.

 

[Chas]

In this case it is not more than automating a train line, with one person watching the big board for flashing lights just in case. Who wants these boring jobs in cargo tramps doing the same thing light year in and light year out anyhoo? Free trading's where it's at man.

 

[AnotherDilbert]

Note that the crew requirements on p19-20 talk about people required, not functions fulfilled.

Virtual Crew: While ships are vastly complicated to run, requiring highly trained crews, relatively simple operations can be performed by this software package. Virtual Crew can replace up to five pilots, gunners or sensor operators on board a ship, potentially allowing the ship to act completely autonomously if all crew can be replaced in this way.

Note that engineers and astrogators are not replaced, so starships cannot be completely automated by RAW.

I will cling to my illusions as long as I can...

 

[Chas]

Actually I'd suggest a set up like this would have automated ships running the routes, the limited number of precalculated jump options and navigation done elsewhere by astrogators and piped aboard, but with human crewed support and maintenance vessels or space stations... specialized vessels which could more efficiently do all manner of jobs with workshops and spare parts included on board.

 

[phavoc]

A ship using drop tanks cannot be streamlined – at best, it will be partially streamlined.

Ok. So we are left to infer that a ship with drop tanks attached can skim. It's not implicitly implied, nor is it categorically denied. Me doth thinks that this was another thing never thought of when drop tanks were created.

 

[AnotherDilbert]

Me doth thinks that this was another thing never thought of when drop tanks were created.

It probably was, around 1980, when drop tanks were introduced in original High Guard. It was specifically considered and detailed in 1981 when the original Trillion Credit Squadron was published.

Drop Tanks are not new or untested in Traveller.

 

[phavoc]

Me doth thinks that this was another thing never thought of when drop tanks were created.

It probably was, around 1980, when drop tanks were introduced in original High Guard. It was specifically considered and detailed in 1981 when the original Trillion Credit Squadron was published.

Drop Tanks are not new or untested in Traveller.

I agree. With your statement in regards to drop tanks. However, drop tanks weren't always so survivable (don't have my FFE CD's in front of me, so I can't verify that thought at the moment).

But, to my original point, the way that they are being envisioned now, with ships putting ALL their jump fuel in drop tanks... THAT is not present in any TCS or HG design I have ever seen or recall reading. And THAT remains my point.

 

[AnotherDilbert]

But, to my original point, the way that they are being envisioned now, with ships putting ALL their jump fuel in drop tanks... THAT is not present in any TCS or HG design I have ever seen or recall reading. And THAT remains my point.

Take a look at the TCS tournament winning fleet in JTAS#10 (?).

 

[Chas]

But, to my original point, the way that they are being envisioned now, with ships putting ALL their jump fuel in drop tanks... THAT is not present in any TCS or HG design I have ever seen or recall reading. And THAT remains my point.

? who is doing that?

The only common case I could see for doing all jump fuel in drop tanks would be for civilian use where you are shunting a barge through quick jump to jump and then have a smaller barge to tow or drive at the end of the journey. But that's hardly justifiable. Enough UNREP equipment and you can refill a ship in an hour or two max.

That and drones of course by they're a different kettle of fish.

The most I've proposed is half the fuel in drop tanks and that is as noted barely justifiable. And in that specific use case the drop tanks would be almost never used deliberately in combat but dropped off prior in a conventional fashion.

 

[AnotherDilbert]

? who is doing that?

The ship we are discussing, in the OP?

 

[Chas]

? who is doing that?

The ship we are discussing, in the OP?

Phavoc's angst seemed to be well aflame before that was put up, so I asked. :lol:

But even looking at that OP drop tank design I'd really want to compare that cost effectiveness vs. a cheap fueler. The drop tank still has to be refuled by a system that hauls the drop tank to the fuel station (where the fuel came from somewhere) and then hauled back full to be reconnected. If you have a cheap civilian refueler (and I've been meaning to make the 1 million ton fleet example) that goes down to a gas giant, processes the fuel and is in station to refuel a what I'll call jump barge in a very easily managed system that could also be easily semi-automated. The UNREP equipment is cheap and fast and multi use. Once the investment is made in the refueling vessel you're away, and are not reliant on anybody's else's supply, or issues like hauling the drop tanks around with tugs and whatnot.

 

[phavoc]

I submitted in the last Freelance Traveller a hydrogen fueling system, replete with tugs, fuel pods and all. I put an 8hr time window on the mission time from the time the tug leaves the fuel station in orbit around the gas giant, to flying into the atmosphere, finding the hydrogen, collecting it, and then flying back. It seemed reasonable to me from a time perspective.

My 'angst' is oriented around getting things right the first time. I do dislike systems that don't take into account common sense and require lots of interpretation by players and ref's to figure out just what the hell the rules are supposed to mean. Having a stable and good environment means WE, as the more vocal players, can easily trade designs and such through the forums and contribute to the gaming community.

I don't have my JTAS stuff, but I will look up that article. I'm betting that the TCS design is oriented around making a min/max design fleet to win a battle. Warships are going to be, for the most part, general ships that fulfill specific roles. Look at how destroyers and cruisers and even battleships are designed - battleships less so, but smaller cruisers and destroyers and escorts are usually general ships, designed for many missions. Specialized roles tend to be emphasis towards say missile frigates (that still can be escorts), or escort cruisers (designed to swat torpedoes and fighters, but still can perform the cruiser role). No Navy is ever going to have enough ships to do all it's missions, so it can't afford to tie up precious hull tonnage and personnel for limited roles.

 

[phavoc]

But, to my original point, the way that they are being envisioned now, with ships putting ALL their jump fuel in drop tanks... THAT is not present in any TCS or HG design I have ever seen or recall reading. And THAT remains my point.

Take a look at the TCS tournament winning fleet in JTAS#10 (?).

So I found an interesting thread that discussed this fleet. It brings up some good points. One was that some of the canonical larger ships (like Tigress) only carry enough internal fuel to make a J-3, but have J-4 drives. The implication is that if necessary they can use drop tanks to get that extra parsec. It was mentioned that at 30% of fuel there is plenty of fuel, but at 40% tonnage dedicated to fuel, you start to have to make hard decisions regarding your weaponry. And that sort of argument is a fair one, not like the ones we are having here.

To get back to the winning designs, I think they were allowed under the first tournament's rules, but definitely are min/max designs. First off they are going along the lines of maximizing the number of spinals your fleet can bring to battle. The largest ship was a few tons less than 20,000 (to get under the game-imposed rules, not reality-based.. but one we all live with to game from). Plus they all carried their jump fuel in L-Hyd tanks. A 20,000 ton class vessel carrying 10,000 tons of fuel in drop tanks. Which means all of the ships were essentially riders, but with jump drives. And remember these are tournament designs, essentially being created for one-shot battles. The ultimate in min/max designs. The link is here - https://members.tip.net.au/~davidjw/tavspecs/best_tml/Starships%20(HG)%20-%20Professor%20Lenat%20and%20EURISKO's%20Winning%20Fleet.htm

For another long discussion, that talks about how the 'legendary' fleet really looked for ways to rules lawyer their way to victory are here - http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=15850

 

[Chas]

I submitted in the last Freelance Traveller a hydrogen fueling system, replete with tugs, fuel pods and all. I put an 8hr time window on the mission time from the time the tug leaves the fuel station in orbit around the gas giant, to flying into the atmosphere, finding the hydrogen, collecting it, and then flying back. It seemed reasonable to me from a time perspective.

Ah. That's nice. :!: Refuelers that buzz around from that fuel station is probably better than doing a grab drop tank, haul and refeul and haul and reattach routine with tugs. And isn't TL challenged.

My 'angst' is oriented around getting things right the first time. I do dislike systems that don't take into account common sense and require lots of interpretation by players and ref's to figure out just what the hell the rules are supposed to mean. Having a stable and good environment means WE, as the more vocal players, can easily trade designs and such through the forums and contribute to the gaming community.

This I can relate to. I do dislike it when clarifying text, even if repeating what is put up elsewhere, isn't included, typically to save word space. A well designed User Guide doesn't leave it to chance that you remember something tucked away in another book, each issue is dealt with as a single individual whole to make sure what you need to grasp a concept and carry it out is right there in front of you.

I don't have my JTAS stuff, but I will look up that article. I'm betting that the TCS design is oriented around making a min/max design fleet to win a battle. Warships are going to be, for the most part, general ships that fulfill specific roles. Look at how destroyers and cruisers and even battleships are designed - battleships less so, but smaller cruisers and destroyers and escorts are usually general ships, designed for many missions. Specialized roles tend to be emphasis towards say missile frigates (that still can be escorts), or escort cruisers (designed to swat torpedoes and fighters, but still can perform the cruiser role). No Navy is ever going to have enough ships to do all it's missions, so it can't afford to tie up precious hull tonnage and personnel for limited roles.

Agreed. (To the point where the rules make it feasible, those blasted missile escorts are bad news) Again why I directed my extended drop tank designs to fulfill specific niches.

And EDIT:

It was mentioned that at 30% of fuel there is plenty of fuel, but at 40% tonnage dedicated to fuel, you start to have to make hard decisions regarding your weaponry. And that sort of argument is a fair one, not like the ones we are having here.

That's all I've been doing with my drop tank designs and where I've been coming from all along. Making high firepower strike space superiority ships. Or ultra long jump you cannot do any other way.

 

[phavoc]

A ship using drop tanks cannot be streamlined – at best, it will be partially streamlined.

You aren't answering the question. So let's pull this apart. "A ship using drop tanks cannot be streamlined - at best, it will be partially streamlined"

If you think about this rule, it actually doesn't survive the first logical test - that being it's illogical. First, a ship's hull design has nothing to do with mounting drop tanks on a craft that exists in a vacuum. Therefore one can also argue that this rule itself is broken.

OR, one could say, that ANY streamlined ship, once it takes on drop tanks, becomes partially streamlined, at best. But the 'at best' indicates there is some sort of gradient there. One could infer that this would now mean it COULD go from partially streamlined to being all the way considered as a distributed hull.

And this is where clarity in the rules comes in awful handy. No one has yet cited a single sentence allowing, or prohibiting, craft from entering atmosphere or skimming a gas giant while having drop tanks attached.

So THREE sentences could fix this whole issue "Drop tanks, of an TL, may be destroyed by a ship's jump field. Drop tanks may not be carried externally by a ship through jump. Ships with mounted drop tanks may not gather fuel through skimming of a gas giant, or land on a planet with an atmosphere greater than 3 or a gravity field greater than .2G"

That allows for any starship to mount drop tanks, but it takes away the advantages of them to apply them everywhere. It also puts limitations on the usage of them. This still allows them, but restores the canonical designs to being the defacto standard (i.e. most ships carry all their own fuel, and drop tanks are relegated back to being special-use equipment).

 

[phavoc]

I submitted in the last Freelance Traveller a hydrogen fueling system, replete with tugs, fuel pods and all. I put an 8hr time window on the mission time from the time the tug leaves the fuel station in orbit around the gas giant, to flying into the atmosphere, finding the hydrogen, collecting it, and then flying back. It seemed reasonable to me from a time perspective.

Ah. That's nice. :!: Refuelers that buzz around from that fuel station is probably better than doing a grab drop tank, haul and refeul and haul and reattach routine with tugs. And isn't TL challenged.

I figured that since we are just slinging hydrogen around, there's no actual need to have a ship move it. Plus for some places we are talking about HUGE amounts of hydrogen being needed. So that means we need pipelines in space, or the equivalent of that. I got around that limitation by accelerating the tanks and letting them coast to near their targets where they get picked up and decelerated. And that pushed upwards the size of the tanks. The smallest size was, I think 25,000Dtons. Cool thing was I figured an 'average' of 30 days transit time, so I put in some fuel processors that would allow the tank to fully purify the fuel, so it's ready to be consumed upon arrival.

The original, shorter, article is here - http://www.freelancetraveller.com/features/culture/reference/rhcat.html - but I've since expanded it and it should be coming out soon.

 

[AnotherDilbert]

A ship using drop tanks cannot be streamlined – at best, it will be partially streamlined.

You aren't answering the question. So let's pull this apart. "A ship using drop tanks cannot be streamlined - at best, it will be partially streamlined"

If you think about this rule, it actually doesn't survive the first logical test - that being it's illogical. First, a ship's hull design has nothing to do with mounting drop tanks on a craft that exists in a vacuum. Therefore one can also argue that this rule itself is broken.

OR, one could say, that ANY streamlined ship, once it takes on drop tanks, becomes partially streamlined, at best. But the 'at best' indicates there is some sort of gradient there. One could infer that this would now mean it COULD go from partially streamlined to being all the way considered as a distributed hull.

I agree that the rule is not perfectly clear. I see it as another condition on the ships streamlining:

SHIP CONFIG         WITH DROP TANKS
Unstreamlined       Unstreamlined
Partially           Partially
Streamlined         Partially

so a ship with drop tanks can be partially streamlined, at best, not guaranteed.

And this is where clarity in the rules comes in awful handy. No one has yet cited a single sentence allowing, or prohibiting, craft from entering atmosphere or skimming a gas giant while having drop tanks attached.

Partial streamlining means that the ship can enter atmospheres, hence it can skim fuel.

Partial streamlining allows a ship to skim gas giants and enter Atmosphere codes of 3 or less, acting in the same way as streamlined ships. In other atmospheres, the ship will be ponderous and unresponsive, reliant on its thrusters to keep it aloft. All Pilot checks will be made with DM-2.

Nowhere is it stated or implied that drop tanks are so fragile that they will fall off or disintegrate at a gust of wind. Aircraft drop tanks today can withstand a few G and a full atmosphere. The Imperium has had 3000 years to refine the concept.

So THREE sentences could fix this whole issue "Drop tanks, of an TL, may be destroyed by a ship's jump field. Drop tanks may not be carried externally by a ship through jump. Ships with mounted drop tanks may not gather fuel through skimming of a gas giant, or land on a planet with an atmosphere greater than 3 or a gravity field greater than .2G"

This is not how drop tanks have ever worked in Traveller. You want to change them to something more fragile. That is your prerogative.

But at this point I'm pretty much argued out over the topic.

I have to agree with you on this.