Future Tech Advice and Assistance Thread [O.O.C.]

[The V O I D]

The Void makes use of AutoGens. No one really knows what they're powered by, but they're self-sustaining and generate not only power for all ships and cities, but they also power themselves and generate their own fuel within. Problem solved.

[Interstellar Planets]

Logistics is an aspect of warfare most seem to forget in FT. Ships are going to need to be refueled, whether they run on antimatter, hypermatter, or whatever it is you use.

What if you use Bussard Ramjets? I assume you need more fuel to power the ship

But can you collect enough hydrogen while moving to use it both to power your ship and the ramjet indefinitely? Can you build a ship that never needs refueling?

Assuming you are using a traditional Bussard ramjet concept (hydrogen is compressed to the point of thermonuclear fusion by the magnetic scoop, with the energy spat out the back like a rocket), you'd have at least three problems:

1. It only works if you get up to a high speed in the first place, else the hydrogen isn't swept up fast enough to sustain the fusion reaction. You'd still need a separate engine with its own power source to accelerate up to speed, and possibly for emergency deceleration (relying on the drag effect of the scoop - i.e. turning off the fusion reaction but continuing to collect hydrogen - might be too slow).
2. The magnetic scoop would have to be enormous, even more so than the original concept called for as Bussard may have over-estimated how much free-floating hydrogen there is be beyond the Sun's heliosphere. We're talking dozens, if not hundreds, of kilometres across. Generating that may be somewhat power-intensive, and building a physical scoop would be infeasible and stupid-looking.
3. Hydrogen approaching the magnetic scoop would need to be ionised by a powerful laser or something, otherwise it would be unaffected by the magnetic field.

There's also a question about drag, insomuch as you'd essentially be fighting against the drag of your own fuel source.

I view it as unlikely that you could get all of your power requirements from the Bussard ramjet, personally. But there's certainly an argument to incorporate the Bussard method for some of your fuel needs. Hydrogen is useful for both fusion and chemical rockets, so you may as well gather some even if it's just going into storage somewhere.

[Tierra Prime]

Logistics is an aspect of warfare most seem to forget in FT. Ships are going to need to be refueled, whether they run on antimatter, hypermatter, or whatever it is you use.

Can you build a ship that never needs refueling?

Unless your ship is powered by a localised singularity, I'd say no. Even nuclear reactors need to be refuelled every twenty years or so.

[The United Dominion]

Can you build a ship that never needs refueling?

Unless your ship is powered by a localised singularity, I'd say no. Even nuclear reactors need to be refuelled every twenty years or so.

Your last sentence is exactly why logistics (this particular part, anyway) are often "forgotten" by most. If you only need to refuel every twenty years, it's completely irrelevant to any RP unless you're using it very specifically as a plot point.

[Feazanthia]

To expand on that - while I agree that logistics is an important but oft-overlooked aspect of FT RP, fuel should only rarely be a concern with most conventional drives. The fact of the matter is that there's very little reason to have vessels on lengthy patrols. Even if one has a relatively large empire and a relatively slow FTL capability, it would be far more cost effective to have local garrisons rather than extended patrol fleets.

There is little reason to patrol the vast, empty tracts of interstellar space - there's nothing out there worth defending, and it's simply so mind-bogglingly big that there's no reasonable way to monitor it without techwank (which would, by extension, largely negate the need for interstellar patrol). Even when monitoring is needed, it makes far more sense to have sensor buoys and/or message drones out along the borders rather than manned vessels.

No, large and fuel-hungry ships will mostly stay in or around port, only deploying to respond to crises, conduct operations, or embark on the odd training cruise. Thus, they will generally only need to be short range, with much of their fuel mass reserved for sublight maneuvers.

In the event of protracted warfare, tender ships can easily provide refueling services in addition to basic repair and rearm.

[Tierra Prime]

Unless your ship is powered by a localised singularity, I'd say no. Even nuclear reactors need to be refuelled every twenty years or so.

Your last sentence is exactly why logistics (this particular part, anyway) are often "forgotten" by most. If you only need to refuel every twenty years, it's completely irrelevant to any RP unless you're using it very specifically as a plot point.

That depends on how your FTL drives work. Twenty years is only for modern ships, starships are going to have much larger energy requirements.

I keep my FTL drives separate from my reactors, so they have to be refuelled once every few hundred thousand light years or so, depending on the size of the ship.

[Source Swarm]

Your last sentence is exactly why logistics (this particular part, anyway) are often "forgotten" by most. If you only need to refuel every twenty years, it's completely irrelevant to any RP unless you're using it very specifically as a plot point.

That depends on how your FTL drives work. Twenty years is only for modern ships, starships are going to have much larger energy requirements.

I keep my FTL drives separate from my reactors, so they have to be refuelled once every few hundred thousand light years or so, depending on the size of the ship.

With regards to this matter (that is, fuel and endurance), there's a number of ways to look at the problem, both FTL and sublight.

For one, unless you're handwaving, you're going to need reaction mass (remass for short) for your engines. Newtonian physics and all that. So you're going to be stopping at depots for hydrogen, or whatever atom-molecule you like to fling aft as hard as you can. Then, depending on your FTL tech, the drives themselves will need periodic overhauls.

Another concern is that - like real-life large vessels - your ships are never going to be in perfect working order. Port calls allow time to refit things you can't fix on the fly.

[OMGeverynameistaken]

That depends on how your FTL drives work. Twenty years is only for modern ships, starships are going to have much larger energy requirements.

I keep my FTL drives separate from my reactors, so they have to be refuelled once every few hundred thousand light years or so, depending on the size of the ship.

With regards to this matter (that is, fuel and endurance), there's a number of ways to look at the problem, both FTL and sublight.

For one, unless you're handwaving, you're going to need reaction mass (remass for short) for your engines. Newtonian physics and all that. So you're going to be stopping at depots for hydrogen, or whatever atom-molecule you like to fling aft as hard as you can. Then, depending on your FTL tech, the drives themselves will need periodic overhauls.

Another concern is that - like real-life large vessels - your ships are never going to be in perfect working order. Port calls allow time to refit things you can't fix on the fly.

Apparently NASA is currently testing the EM drive and results seem promising. So a 'reactionless drive' is no longer, strictly speaking, a handwave. Although an accurate EM drive spaceship is going to accelerate quite slowly.

[Imperial Nalydya]

To expand on that - while I agree that logistics is an important but oft-overlooked aspect of FT RP, fuel should only rarely be a concern with most conventional drives. The fact of the matter is that there's very little reason to have vessels on lengthy patrols. Even if one has a relatively large empire and a relatively slow FTL capability, it would be far more cost effective to have local garrisons rather than extended patrol fleets.

There is little reason to patrol the vast, empty tracts of interstellar space - there's nothing out there worth defending, and it's simply so mind-bogglingly big that there's no reasonable way to monitor it without techwank (which would, by extension, largely negate the need for interstellar patrol). Even when monitoring is needed, it makes far more sense to have sensor buoys and/or message drones out along the borders rather than manned vessels.

No, large and fuel-hungry ships will mostly stay in or around port, only deploying to respond to crises, conduct operations, or embark on the odd training cruise. Thus, they will generally only need to be short range, with much of their fuel mass reserved for sublight maneuvers.

In the event of protracted warfare, tender ships can easily provide refueling services in addition to basic repair and rearm.

We actually do have vessels and units that go out for extended patrol, but they do so from the rift and so can cover vastly more ground than anything in real space. This isn't really out of a need to defend anything (they're not patrolling Pordish space) but rather, it's more to keep an eye on the goings-on of the wider verse.

Similarly, fuel is largely a non-issue because the rift itself is a chaotic realm, and its pure, unadulterated hatred and rage have long since been tapped into and harnessed to power our vessels and their systems.

The others are right though. Even in the days where our fuel was limited ships went out on extended patrol so rarely that running out of fuel was such a minor concern that it wasn't really even worth worrying about. The vast majority of the battlewagons sat around planets in their orbitals not really using up all that much fuel. Campaigns were largely short and didn't really require vessels with great endurance.

[SquareDisc City]

I'd just bear in mind logistics is much wider than fuel. Depending on tech fuel might be the easy bit - a fusion-powered ship could plausibly self-refuel from a gas giant for example. Harder is stuff that isn't a raw material but needs to be produced - food, spare parts, munitions, and so on. Then there's what I might call "soft" factors. Sure, a ship's crew can be on an isolated 20-year deployment, but morale is probably much better if they get emails, parcels, 'shore leave', and a sensible-length tour of duty before a new crew is rotated in.

How much it will come into RP is obviously going to vary. In a straight-up space battle logistics might not matter much. If you're writing about "boots on the ground" it's going to be more important, though still not necessarily the focus. And in a siege or blockade situation logistics may become front-and-centre to the plot.

Whatever the details, chances are there are good reasons to get Stuff from There to Here, or/and to stop another nation doing so. Even when it's not the focus of the writing, it's still something to add interest.

[Excidium Planetis]

Can you build a ship that never needs refueling?

Unless your ship is powered by a localised singularity, I'd say no. Even nuclear reactors need to be refuelled every twenty years or so.

You took my sentence out of context... In my post, I was specifically referring to the use of a magnetic scoop to pick up free floating hydrogen during space travel, which could theoretically supply your ship with fuel as it moves, thus negating the requirement for stopping to refuel.

While the actual tech and power requirements to get it going are huge, given the amount of tech "wank" most FT nations use (handheld and lethal Directed Energy Weapons? Mechs? Energy shields?), it is not improbable that some nations could utilize such a set up to eliminate the need to refuel.

Apparently NASA is currently testing the EM drive and results seem promising. So a 'reactionless drive' is no longer, strictly speaking, a handwave. Although an accurate EM drive spaceship is going to accelerate quite slowly.

So far, the EM drive has a handful of unreviewed experiments whose reported measurements are so small they fall within experimental error range. And the designer of the EM drive has been criticized in the past for incorrect science, so I don't hold out much hope for realistic reactionless drives.

[The United Dominion]

Unless your ship is powered by a localised singularity, I'd say no. Even nuclear reactors need to be refuelled every twenty years or so.

You took my sentence out of context... In my post, I was specifically referring to the use of a magnetic scoop to pick up free floating hydrogen during space travel, which could theoretically supply your ship with fuel as it moves, thus negating the requirement for stopping to refuel.

While the actual tech and power requirements to get it going are huge, given the amount of tech "wank" most FT nations use (handheld and lethal Directed Energy Weapons? Mechs? Energy shields?), it is not improbable that some nations could utilize such a set up to eliminate the need to refuel.

Given that "wank" is an insulting term, maybe you shouldn't use it to describe classic aspects of the scifi genre to which the majority of the FT community subscribes.

That said, you're definitely right that it's not improbable for ships to not require refueling. But even in the cases where they might, if you have, say, a range of 150-200,000 LY, sheer IC incompetence or a series of plot-derived (and probably plot-hole filled) catastrophic events are the only ways refueling would likely be a concern.

That's why it's not a worthwhile aspect of logistics for most people. Food, water, atmosphere, and spare parts are far more likely to be relevant. And even then, I'd question it being important or coming up at all in most circumstances. The most that the majority of us probably need is "we send out tender ships as necessary."

[Excidium Planetis]

You took my sentence out of context... In my post, I was specifically referring to the use of a magnetic scoop to pick up free floating hydrogen during space travel, which could theoretically supply your ship with fuel as it moves, thus negating the requirement for stopping to refuel.

While the actual tech and power requirements to get it going are huge, given the amount of tech "wank" most FT nations use (handheld and lethal Directed Energy Weapons? Mechs? Energy shields?), it is not improbable that some nations could utilize such a set up to eliminate the need to refuel.

Given that "wank" is an insulting term, maybe you shouldn't use it to describe classic aspects of the scifi genre to which the majority of the FT community subscribes.

It was in quotations for a reason. Anyhow, I couldn't think of a better term for what I wanted to describe at the time, though I suppose "handwaving" would have been a better term.

That said, you're definitely right that it's not improbable for ships to not require refueling. But even in the cases where they might, if you have, say, a range of 150-200,000 LY, sheer IC incompetence or a series of plot-derived (and probably plot-hole filled) catastrophic events are the only ways refueling would likely be a concern.

That's why it's not a worthwhile aspect of logistics for most people. Food, water, atmosphere, and spare parts are far more likely to be relevant. And even then, I'd question it being important or coming up at all in most circumstances. The most that the majority of us probably need is "we send out tender ships as necessary."

The most logistics I've bothered with is "we kind of need these asteroids to mine or our fleets will run out of resources". When you have space battles that only last several hours or so, fuel and food are not much of a concern.

[The Akasha Colony]

Unless your ship is powered by a localised singularity, I'd say no. Even nuclear reactors need to be refuelled every twenty years or so.

You took my sentence out of context... In my post, I was specifically referring to the use of a magnetic scoop to pick up free floating hydrogen during space travel, which could theoretically supply your ship with fuel as it moves, thus negating the requirement for stopping to refuel.

While the actual tech and power requirements to get it going are huge, given the amount of tech "wank" most FT nations use (handheld and lethal Directed Energy Weapons? Mechs? Energy shields?), it is not improbable that some nations could utilize such a set up to eliminate the need to refuel.

No, because then you'd have a perpetual motion machine, which violates the laws of thermodynamics.

As it stands, a Bussard ramjet is not designed to gather fuel, it gathers reaction mass. The ramjet was designed to gather and compress free hydrogen to the point where it naturally underwent fusion and would then be expelled to the rear of the craft, as thrust. However, the system would still require a separate power source for the magnetic fields. The benefit of this system is that you would not have to carry the reaction mass onboard, you would only need to carry the fuel mass for the power system. It's the same as the difference between an air-breathing engine and a rocket: the air-breathing engine can rely on atmospheric oxygen, eliminating the need to carry a separate oxidizer.

[The Ten Thousand Suns]

Without being able to find the actual papers on the subject that calculate reaction mass/mass of ship needed/etc, I believe the problem with bussard collectors is that space is a lot emptier than Bussard thought. A physical scoop wouldn't be able to collect enough to provide effective propulsion unless it was in an unfeasibly dense nebula.

The model that I've seen that works on paper relies on a gigantic magnetic field to scoop up matter, without the added mass of a physical scoop. The matter still isn't dense enough to provide effective thrust in between solar systems (most of the matter you'd be scooping up would be hydrogen ejected from the local star, which is densest near said star), and it would be very difficult to collect anything near any planet that had any sort of electromagnetic field (sorry, but harvesting from gas giants with this system is right out). You would also need a fairly beefy computer to perform the calculations needed to aim the scoop to make use of the solar winds. Which it needs, because the scoop gets practically nothing if its pointed the wrong way (I feel compelled to point out it gets very little if pointed the right way, but if you're not in a hurry or in a gravity well, you could get anywhere in the solar system with a few pounds of matter and the power to eject it).

You might try fusing this tech with its child technology - the solar sail. Using the same concepts as the magnetic scoop, it uses the velocity of the solar winds to push the spacecraft along. The solar sail (usually magnetic, just like your scoop) is great for going away from the star, but not so good at going towards it (the star is what's generating the wind, after all). The bussard scoop could provide the thrust to allow the spacecraft to accelerate towards the star.

So, if you want your science fiction to be as hard as possible, a bussard collector/solar sail combo would be able to get you around star systems fairly cheaply (you still need a power supply - even Bussard didn't think that would work) - but your ships would go very slowly. And you'd need some sort of FTL drive to get you between stars (and you'd need to justify why they didn't just use that to get around).

All of that aside, however, this is science FICTION. If you like the idea of Star Trek-style bussard collectors, do it. The collectors are a neat and interesting idea, and if you like them, you should roll with them. When asked "how does it work?", have your ship captain respond "I don't know, I don't have a degree in physics."

[Excidium Planetis]

You took my sentence out of context... In my post, I was specifically referring to the use of a magnetic scoop to pick up free floating hydrogen during space travel, which could theoretically supply your ship with fuel as it moves, thus negating the requirement for stopping to refuel.

While the actual tech and power requirements to get it going are huge, given the amount of tech "wank" most FT nations use (handheld and lethal Directed Energy Weapons? Mechs? Energy shields?), it is not improbable that some nations could utilize such a set up to eliminate the need to refuel.

No, because then you'd have a perpetual motion machine, which violates the laws of thermodynamics.

No, it isn't, because it uses up hydrogen in a chemical reaction. That does not violate the laws of thermodynamics.

As it stands, a Bussard ramjet is not designed to gather fuel, it gathers reaction mass. The ramjet was designed to gather and compress free hydrogen to the point where it naturally underwent fusion and would then be expelled to the rear of the craft, as thrust. However, the system would still require a separate power source for the magnetic fields. The benefit of this system is that you would not have to carry the reaction mass onboard, you would only need to carry the fuel mass for the power system. It's the same as the difference between an air-breathing engine and a rocket: the air-breathing engine can rely on atmospheric oxygen, eliminating the need to carry a separate oxidizer.

I understand what a Bussard Ramjet is. But the nuclear fusion can provide power for the magnetic field as well as for thrust, yes? You simply need a magnetic field strong enough (or a ship traveling fast enough) to collect enough hydrogen for both.

[Source Swarm]

No, because then you'd have a perpetual motion machine, which violates the laws of thermodynamics.

No, it isn't, because it uses up hydrogen in a chemical reaction. That does not violate the laws of thermodynamics.

As it stands, a Bussard ramjet is not designed to gather fuel, it gathers reaction mass. The ramjet was designed to gather and compress free hydrogen to the point where it naturally underwent fusion and would then be expelled to the rear of the craft, as thrust. However, the system would still require a separate power source for the magnetic fields. The benefit of this system is that you would not have to carry the reaction mass onboard, you would only need to carry the fuel mass for the power system. It's the same as the difference between an air-breathing engine and a rocket: the air-breathing engine can rely on atmospheric oxygen, eliminating the need to carry a separate oxidizer.

I understand what a Bussard Ramjet is. But the nuclear fusion can provide power for the magnetic field as well as for thrust, yes? You simply need a magnetic field strong enough (or a ship traveling fast enough) to collect enough hydrogen for both.

Which requires more energy the bigger you make the field.

An overunity device always violates thermodynamics. And Hydrogen Fusion is a nuclear reaction, not a chemical one.

[Excidium Planetis]

No, it isn't, because it uses up hydrogen in a chemical reaction. That does not violate the laws of thermodynamics.


I understand what a Bussard Ramjet is. But the nuclear fusion can provide power for the magnetic field as well as for thrust, yes? You simply need a magnetic field strong enough (or a ship traveling fast enough) to collect enough hydrogen for both.

Which requires more energy the bigger you make the field.

An overunity device always violates thermodynamics. And Hydrogen Fusion is a nuclear reaction, not a chemical one.

Then we'll settle for more starship speed, rather than a larger magnetic field. Then we will still scoop up more hydrogen for the same power usage.

Also, what the heck is an overunity device?
(and yes, you are right, it is a nuclear reaction)

[Source Swarm]

Which requires more energy the bigger you make the field.

An overunity device always violates thermodynamics. And Hydrogen Fusion is a nuclear reaction, not a chemical one.

Then we'll settle for more starship speed, rather than a larger magnetic field. Then we will still scoop up more hydrogen for the same power usage.

Also, what the heck is an overunity device?
(and yes, you are right, it is a nuclear reaction)

Any device capable of generating more energy than is put into it. Say, a Brussard Ramjet with an EM scoop and the fusion core AND the remass all provided by the ambient hydrogen collected in flight.

It might have very very long endurance... but you're going to have to get it up to speed first. And then slow it down. Otherwise it is of no use at all.

(Brussard Ramjets don't work the way you describe either. They gather interstellar medium for reaction mass to be accelerated by the heat of the onboard reactor. The fusion reactor is prefulled before the BR-bearing vessel ever leaves port. I suppose its fusion could be sustained by diverting some of the captured hydrogen (not all of which will be isotopically useful for fusion) into the core, you need a hell of a lot more hydrogen than would be available.

Making the ship faster doesn't solve the energy problem either. You're just moving the expenditure from the magnetic field to the speed. (And that's not how orbital mechanics works anyway.)

Can a ship with functionally infinite endurance exist in FT? Sure, but it's not hard scifi.

[Korhal IVV]

Are pylons alright?

[The Akasha Colony]

Then we'll settle for more starship speed, rather than a larger magnetic field. Then we will still scoop up more hydrogen for the same power usage.

No you won't. Going faster means you end up with more drag, the same as if you had used a larger scoop. That's inevitable, because your goal is to scoop the same amount of hydrogen.

The problem with a Bussard ramjet is the amount of energy required to not just scoop up the hydrogen but to compress it to sufficient densities to achieve fusion. That was the problem to which no solution was found, and it became worse when it was realized the interstellar medium was less dense than Robert Bussard expected when he proposed his design. That's why the "rocket-ramjet" hybrid was later proposed, using the scooped hydrogen solely as reaction mass and not as the actual power source.

[Feazanthia]

Are pylons alright?

The problem with pylons is that you never have enough. You always need to construct additional ones.


(Seriously though, how do you mean?)

[Tierra Prime]

I've stated in the support ships section of my factbook that some of my transport ships have been converted into carriers, though I haven't detailed these carriers in the warship section of my factbook. My navy would consider these carriers ad hoc modifications of the original transports, not actual, dedicated fleet carriers, so does it make sense they aren't included in the warship section? I haven't put down any stats for them in the support ship section either, all I did was say they can exist.

"Due to their large size, some Endeavour-class transports have been converted into heavy fleet carriers, designated the Vengeance-class, which are capable of carrying up to four hundred starcraft of varying types, including bombers."

[Transvaal Vrystaat]

Generally, speaking, a carrier is a carrier regardless of what it started life as. It will certainly be considered a combatant by the enemy because it's carrying craft capable of offensive action, so I see no reason not to class it as a warship.

[Lubyak]

I've stated in the support ships section of my factbook that some of my transport ships have been converted into carriers, though I haven't detailed these carriers in the warship section of my factbook. My navy would consider these carriers ad hoc modifications of the original transports, not actual, dedicated fleet carriers, so does it make sense they aren't included in the warship section? I haven't put down any stats for them in the support ship section either, all I did was say they can exist.

"Due to their large size, some Endeavour-class transports have been converted into heavy fleet carriers, designated the Vengeance-class, which are capable of carrying up to four hundred starcraft of varying types, including bombers."

Well, since there's no inter-stellar treaty in FT that defines what a fleet carrier or a combatant is you can do anything you want. However, it sounds similar to IJN and USN programs to convert merchantmen and other civilian ships into carriers during World War II. (See, e.g. Sangamon class and Taiyo class) Although smaller in scale than fleet carriers, they were definitely still considered combatants. Legally, I'm certain most would consider a merchantman conversion into a warship a combatant, and subject to the laws of war as a combatant. Nonetheless, if you want to say it's still classified as a merchantman rather than a warship, feel free to do so.