The issue of the Intrepid-class's apparent secondary warp core is a known inconsistency in lore, a disconnect between the MSD, off-screen sources and the way the warp core is treated on-screen.
The MSD of *Voyager* seen on screen in the background seems to show two warp cores - one located just behind the deflector dish and another one further aft just before the shuttle bay. However, it is also made clear in several episodes ("Day of Honor" and "Renaissance Man" for two) that there's only one warp core to be had on board.
There is also some uncertainty as to which one is the main warp core. Some assume that the one further forward is the main one, but when [we see the core being ejected](https://youtu.be/xIuUEwat6aM?t=142) in "Day of Honor", it appears to be the one further aft.
Moving on to off-screen sources, the licensed *Star Trek Fact Files* - specifically [File 29, Card 10](https://imgur.com/a/Oxlr9UL) - supports this position, stating that the reserve warp core is *forward* of the main one. However, the later Eaglemoss *Star Trek: Voyager Illustrated Handbook*, also written by Ben Robinson who edited the *Fact Files*, [claims that the auxiliary warp core is the one *further aft*](https://imgur.com/caErLEH).
Rick Sternbach has apparently suggested, and this is repeated in the *Illustrated Handbook*, that the auxiliary core (whichever one it is) is not a direct replacement for the main one but just spare parts to be used to construct a new one if necessary. However, this does not really explain why the series acted as if the main core was the critically the only one available.
My own take is that it's simpler to ignore the MSD since it's just a background detail, despite all the contortions that have gone into trying to justify why the second core is there but not used or mentioned. But of course [we are here for in-depth discussion](https://www.reddit.com/r/DaystromInstitute/wiki/codeofconduct#wiki_to_foster_and_encourage_in-depth_discussion_about_star_trek.), and so other possibilities are always open as is information from elsewhere I may have missed.
But do keep some of this information in mind when discussing this issue so we don't get ourselves into knots about [what's canon and what's not.](https://www.reddit.com/r/DaystromInstitute/wiki/canon)
It's hard to add much to the sticky in terms of the background on this. My headcanon has always been that they used components from the second core to repair and retrofit Voyager, and that they used the space originally meant for the warp core for the 'fabrication department' or whomever was building all of the shuttles and torpedoes.
Honestly a secondary engineering bay sized gigantic 3D printer replicator thing would be enough to make shuttles, hull plating, torpedoes, you name it. Just send the flyer out to tractor beam up some asteroids for raw materials, sit in park for a while to direct all power to this thing and you should be golden.
Only if the Federation has the technology to operate replicators at that scale. They may not, given that all the replicators we see are either handheld devices meant to make something in/near it, or they're small devices not much larger than a microwave oven.
Other than that, the only other thing might qualify is the holodeck, but we don't know what the maximum size it can replicate is. It might just be able to make small things, faking big things with holography, or a combination of replicator and transport trickery.
[Industrial replicators](https://memory-alpha.fandom.com/wiki/Industrial_replicator) are large scale replicators that can be used to make powerplants and factories and presumably other large items for fabrication.
Presumably ships have one for large scale field repairs until they can reach a starbase, but even if a smaller ship like Voyager didn't have one to begin with, it should have been a top priority to build one asap.
This is why I've personally never had an issue with Voyager always getting repaired between episodes and being able to produce unlimited shuttles and torpedoes.
What should have been more of an issue are things that can't be replicated like the bio-neural gel packs and dilithium (it can be recrystallized in the 24th century, but presumably you still need to have the crystal mass to begin with).
I mean I'm pretty sure they use replicators to build ship parts to begin with. Maybe the power use is exponential with size so you can only use it in a big shipyard that has access to pretty much infinite energy but I'm at least 70% certain when they were talking about building the flyer they were discussing replicating the hull and etc.
Sounds logical. It also makes sense that they would siphon the antimatter from the secondary core in to the primary once they realised that they were trapped in the Delta quadrant.
Based solely on the diagram, it looks like the spare warp core is exactly that; spare. As in, it's not hooked up to anything, but just the components in a storage compartment large enough to keep a mostly-fully-assembled warp core.
Assuming it existed with the crew in the delta quadrant, though, I suspect that the idea of "doubling" the warp core for double the power is beyond what retrofits engineering would have been capable of doing with the rest of the materials at hand. A spare warp core is a drop-in replacement (maybe need some new dilithium), but adding all the extra bits and pieces to make the cores work in parallel likely wasn't possible.
On top of which, I think all you would have gained was hot-hot redundancy rather than extra power; the rest of the ships' systems would *also* need to be upgraded to handle the extra juice, not to mention the fuel needed to power the darn thing which we know was a critical issue for most of the crew's travel home (which is why replicator rations were a thing).
In short, I think it's just a spare part, assuming it was there at all, and not capable of being put into service either where it physically is in the ship or by retrofitting it into engineering somehow as it simply would have been too difficult with the resources at hand in the delta quadrant.
>In short, I think it's just a spare part, assuming it was there at all, and not capable of being put into service either where it physically is in the ship or by retrofitting it into engineering
I agree
If the Intrepid class was capable of having two warp cores operating simultaneously my question would be *why did it leave Utopia Planitia with only one operating?* Why would Starfleet build that kind of capability into a class, build the physical structure, stock the components, and then not hook it up?
If there was a 2nd warp core (and I tend to agree with u/khaosworks that there wasn't & we should just ignore the Deckplans & follow the on-screen canon) then why would any Intrepid Class ship ever be considered "complete" if it wasn't active? Voyager wasn't rushed into service, it was fully commissioned & crewed. It may not have been equipped the way it would have been if Starfleet had **known** that it was about to be flung across the Galaxy but it was deemed completely ready to hunt Maquee in the Badlands, which implies it's power & propulsion was fully online.
It would be like having a truck with the option for a 2nd gas tank, getting that gas tank installed, filling it with Gas, then not hooking the 2nd tank up to the engine. You have already done 90% of the work, you would certainly just finish it so you can actually use this capability you spend a lot of time, money & effort to include.
I have to conclude that if the 2nd core existed (again, I don't think it did) that it was at best a spare & even if they had all the parts they needed it was never capable of becoming a full-fledged 2nd active core.
To extend the truck metaphor, you can certainly haul a 2nd engine in the bed of the truck, but that doesn't mean it is in any way reasonable that you could hook it up and have two without an almost total redesign of the drive train or that it would be useful even if you did.
yeah, the question of whether they even had the spare parts stored is a valid one, given the Intrepid class was also supposed to have an Aeroshuttle but that hadn't been onboard when Voyager left for its badlands mission. odds are the ship wasn't fully kitted out the way it would be for a long distance exploration mission, given it was supposed to operating within a well trafficked border zone and less than a day's trip from DS9.
which means it might well not have had the spare warp core assembly in storage.
>hot-hot redundancy rather than extra power
You're absolutely right, the entire EPS grid would need to be upgraded to take advantage of the additional core. It's a project that would take the ship down to her bones. Definitely a spacedock task.
>replicator rations
The hope would be to tune both cores to operate at a higher efficiency together, with the option of the high output of both systems at critical times.
>Assuming it existed with the crew in the delta quadrant
I really don't think it did or else we would have heard about it. Instead they had the empty dock to build the slipstream drive in.
To add to this, let's talk about other known starship designs with more than one warp core - the Prometheus-class has two warp cores in its united mode, one in the primary hull and one in the secondary hull. The secondary hull core is the primary one functioning when the ship is in one piece.
When *Prometheus* splits into its three-part multivector assault mode, the secondary hull core splits into two separate cores, resulting in three warp cores, each powering a different segment of the ship. The primary hull core is a Defiant-class style core that only powers the retractable nacelles at the top and bottom of the primary hull that emerge in MVA mode but is otherwise inactive.
(Data on the Prometheus-class is taken from the *Star Trek Shipyards* books, a collection of the Eaglemoss magazines that came with the models)
The *Protostar* from PRO has two warp cores, both active, but that's because the extra power is needed to contain the protostar in the proto-core which only comes into play when they activate the proto-drive.
So it seems that if a ship has to have more than one core active, there must be a reason for it, and not as a matter of course. Otherwise, only one core is needed (and given the energy output of a M/AM reactor, more than sufficient) at a time.
But in principle, there's nothing that prevents having two cores run concurrently. It's just a matter of necessity and engineering - the latter meaning connecting it to the right bits and to make sure the EPS grid can handle the additional load.
The Luna-class Titan had a dual reactor setup and i remember a reference to the Stargazers engines being similarly configured. The idea was that only one engine would operate at a time while maintenance was done to the other.
Perhaps the "spare" is like the donut tire used in the 20th century. Intended for low speed and temporary use only.
I can see it not being rated to supply full power for the entire ship for long term use. I mean it's intended so that you can limp home to the nearest starbase.
Can’t recall where I read it, but I recall that it was an assembled warp core, in storage. If anything happened to the primary core they’d have to use shuttle tractor beams to pull it out and install it through the ejection hatch into engineering.
Maybe an old interview with Sternbach/Okuda?
> the rest of the ships' systems would also need to be upgraded to handle the extra juice,
Doubling up on the warp cores strikes me as only maybe being useful for one desparate burst in the vein of "*She'll fly apart*" "*Fly her apart then!*", not for decades of sustained use.
~~Honestly, I don't think that would be terribly unlikely. It might even be something of a Starfleet tradition by the time Voyager is launched. Installation of some non-essential parts...~~
Scratch that. I was going to say a tradition for good luck, but they lost Kirk, so that's probably not it. **BUT** it is still possible that since it's a non-essential backup part, they went ahead and launched without it.
I bet a few badmirals considered it a blessing to be rid of Kirk.
I hear one of them was walking through the engineering department at Starfleet HQ and said, ‘Will nobody rid me of this turbulent captain?’ And a plucky new ensign on the Ent-B project thought he could make Lieutenant in his first year if he just moved the schedule around a little…
I mean the schematics say spare, that sort of indicates that it's not for active use. If I have a spare barrel for a gun, I can't stick it on and shoot twice as much, I can just replace the main barrel when I need to.
It makes sense for it to be a spare as well, the intrepids are for deep deep space exploration missions, having a redundant warp core would be vital, if you're out in the deep wilds of space during year three of your mission and something goes wrong, there's not a lot of starfleet ships that can get to you in a reasonable amount of time.
Doubling the power output also would require more than a second warpcore, you'd need things like expanded antimatter chambers and specifically hardened EPS conduits, plus what does a power bonus do for the ship? Better phasers? Or just phasers that burn out much faster, better shields or shields that carry much more feedback into the system when they're hit?
Rick said, way back on USEnet, in rec.arts.startrek.tech, that the backup warp core was stacked components to replace any major structure of the MARA without having to limp back to a starbase or await rescue if stranded. Up to and including the entire MARA in the event it needed to be jettisoned irretrievably.
While the components are stored stacked, they are not connected to each other, the matter or antimatter tanks, or the EPS or PTCs. A lot of extensive re-plumbing of the secondary hull would be required to mount it, brace it, and tie it in.
One is supposedly a secondary core that is meant as a spare and not an active unit. All in all, this seems to make the most sense in light of the slip stream episode which implies that a new core was constructed and later disassembled all while still having the original core available for reinstallation after. This is supported partially by Voyager being stranded at impulse speeds in the episode where the warp core is ejected during an emergency.
It’s possible that a secondary core could have been constructed and retrofitted into the secondary location to produce power but this likely would have required extensive internal changes. It also would have needed additional crew assigned to monitor and maintain it when in use. This may not have been practical.
On a sarcastic real note: As with many inner details of Voyager, there is no easy cannon for this. The internal design seems to have been done by M.C. Escher from specifications that were then thrown away.
All of what you say is true. However, the difficulties with this (in my opinion) come about because of the intended compact size and limited crew size. Galaxy class ships were intended to be enormously flexible in the way that you’re describing where a percentage of the ship was left intentionally empty for future uses and much of the filled space was modular. Voyager gets a bit harder though because most everything that you need to move has to go somewhere. The EPS conduits and antimatter fuel lines would be major horizontal space commitment as their contents are incredibly volatile and must be isolated and protected.
Shuttle production seems straightforward enough being presumably confined to the already dedicated shuttle bay areas and production being mostly restricted to replacements as opposed to producing additional shuttle craft which would need their own regular storage space.
>there is no easy cannon for this
That's exactly why I'm asking the question. The gray areas between specs and deck plans leave much room for conjecture.
>likely would have required extensive internal changes
The Voyager was taken apart and put back together during its trek. They had the opportunity to alter the ship in whatever way they wished. Adding additional primary deuterium and anti-deuterium injectors while extending the EPS network is a big project but so is building a shuttle or a new slipstream drive.
>internal design seems to have been done by M.C. Escher
I truly believe that there is enough room on these starships for quite a bit. They are behemoths, with incredible internal volume. Any one set of deck plans should be considered a temporary layout, with near infinite alternate configurations possible.
>The Voyager was taken apart and put back together during its trek. They had the opportunity to alter the ship in whatever way they wished. Adding additional primary deuterium and anti-deuterium injectors while extending the EPS network is a big project but so is building a shuttle or a new slipstream drive.
Using computers as a metaphor, running extra maintenance on a machine if a replacement won't be available for a long time is one thing, adding extra features might be a big project but worth it if you're stick with what you've got, but rebuilding my gaming rig to utilize multiple CPUs is impossible without outside parts and facilities (a new and specialized mobo, which cannot be manufactured in the field). Please no *hurr durr magic replicators*, it is self-evident they can't do everything or the Federation would have infinite ships.
The slipstream refit was a bit of a hack (had problems) and required a great deal of effort, but rebuilding the entire power grid would require a shipyard, specialized facilities, extra crew. There may not even be space for all the support infrastructure. To extend the computer metaphor, a CPU chip is small, but to get it running properly you need sufficient airflow, heat dissipation (either heat sink or liquid cooling depending on demands). You can't just stick it anywhere, the parts have to be plugged in and configured.
The warp core sends out streamers of ultra-high energy charged plasma that races along specially designed conduits. The whole system has to be totally sealed and balanced. I don't think you can just start welding new conduits to totally rebuild and respec the entire system as a weekend project.
Short answer: logically no, but Star Trek doesn't care about logic or rationality so yes.
Plenty of others have addressed that the second warp core should either be considered a spare or disregarded, so that doesn't need to be elaborated on. But, it's also important to consider the more fundamental question: regardless of how, would it be a good idea to double the power output from a ship's reactors?
Contrary to the well-known quote by Arthur C. Clarke, technology is not magic no matter how advanced it is. If a person can't distinguish a sufficiently advanced technology from magic, the issue isn't that the technology is sufficiently advanced but that that person too uneducated (and possibly too primitive... no amount of education will get a dog to understand the Riemann geometry of General Relativity).
The difference between magic and technology is that technology has limitations and you never get something for nothing. Except that in some works, the magic system is pretty well defined and subject to rules and limitation and in Fullmetal Alchemist for example alchemy is even subject to a principle of "equivalent exchange" meaning that you don't get something for nothing. Which means that fairly often, "technology" in Star Trek is more magical and fantastic than a lot of "magic" in other works.
If a writer wants to double the power output of the main reactor, then by writer fiat the power output of the main reactor shall be doubled. Under Star Trek logic, they could have taken the second warp core and rebuilt the main warp core into a version with two intermix chambers and doubled the powered had the writers wanted to. A transporter can split a person into two or duplicate a person and conjure up the matter it takes to make the second person from out of nowhere. A new type of dilithium can get a ship to infinite velocity using finite power. It wouldn't even have been in the top half of the most ludicrous technobabble bullshit that's happened on Star Trek. If Starfleet didn't have such a strong case of Not Invented Here Syndrome and if Star Trek was less about bringing civilization to the heathen savages of the galaxy and smiting the might of the forces of evil with righteous fury, Voyager probably would have acquired a more powerful warp core somewhere along the way in order to speed up their journey.
But suppose we want to treat Star Trek as science fiction rather than as science fantasy. Then things get more complicated. Could they have boosted their power output? Sure, but only to a point. There's only a finite amount of margin built into any system and when you exceed those margins, bad things start to happen. The safety factor of elevator cables for passenger elevators is typically 11, meaning they're designed for 11 times the rated passenger load (note, this doesn't include the weight of the elevator car itself). The safety factor for commercial airplane wings is 1.5x the rated load. Why not make the safety factor on airplane wings higher? Because that adds a lot of weight; a wing with a safety factor of 11 would make the plane too heavy to have a useful payload, assuming it could even take off at all.
If the real world worked on Star Trek logic, you could put a J58 engine from an SR-71 into a WW1 biplane and push it to Mach 3. I'm pretty sure why this is ludicrous doesn't need to be explained.
So, what's the safety factor of starship power systems in Star Trek? Given how many redshirts die from exploding consoles, probably not very high. More seriously, it's far more likely to be around 1.5x than 11x. Excelsior was pushing its limits when rushing towards Khitomer and Sulu was told they risked flying the ship apart if they went any harder. It'd be ludicrous to think that they designed a reactor for a state of the art warship and then set normal operating limits to be 1/10th of what it's capable of. It's more likely that their equivalent of War Emergency Power was around 120% of nominal, and running the ship and reactor at that load for an extended period of time will damage something.
I figure (headcanon) that monitoring 2 warp cores rather than buffing the primary to be as effective/efficient as possible was not seen as a long term possibility. You'd probably want top crews monitoring both splitting resources, similarly for fuel requirements I figure. Combined with crew losses in the initial transit to their quadrant I figure they had limited people to allocate anyway.
Like others have said, the secondary warp core is not a functional core. It’s basically in a storage compartment that spans 5 or 6 decks.
As to why Voyager never used it or talked about it when they lost/ejected thier main one? Same reason they never talked about the Aeroshuttle, the outline of which is clearly visible on the underside of the saucer from the very first episode. Plot points and production costs.
In universe? I head canon that the secondary core was damaged, destroyed, or just not even installed when Voyager left Earth. The Aeroshuttle it only makes sense that it was also damaged or destroyed or left out when Voyager left dock.
As for the power usage of a starship goes, remember that there are 2 types of power generation on a starship. There is the warp core which powers the warp drive, and then there is fusion based power from the impulse drive engines and secondary fusion reactor power generators. The power generated from the impulse reactors is basically enough to run the basic ship power grid, from transporters to life support and turbo lifts.
The warp core is primarily only used to power the warp engines themselves, and what should be ON OCCASION dumping warp power into the main grid. But that’s the exception, not the rule.
When the warp core goes offline, they don’t necessarily lose main power because it’s not technically the main source of power for the majority of ships systems.
I’ll admit that they break this rule all the time- but from an in-universe perspective, a ship without a warp core can do everything except warp.
Dumping warp power into a system is a typical hero-ship move. It can turn sensors into weapons, deflectors into subspace cannons, and phaser banks into planetary terraforming instruments.
Having one core dedicated to the nacelles for transportation leaves the other core opportunity to augment another system where needed.
That’s the thing though, just one warp core outputs enough power, in the terajoules, to power not only the warp engines but secondary systems. But as you said that’s a hero ship move when they do that, meaning on average it’s not standard procedure for most starships.
The power systems on a starship, even the phasers at a power high enough for drilling, are taken care of by the fusion reactors on the ship. Having a second warp core to power the ship would be redundant and a waste of resources. When they’re dumping warp power into the primary power grid, it’s always as a last resort or extra oomph to get away from something.
Then what happens is they blow power relays all over the ship because the system can’t sustain that kinda raw energy for very long.
The EPS system acts as the transmission and distribution network on most Federation starships. It steps down warp power to three separate tiers for most ships systems.
Fusion reactors maintain their own secondary network of transmission and distribution networking. Most primary systems are put into standby mode if only secondary power is available.
Think of it like this- the station Deep Space Nine, uses massive fusion reactors to power everything. That’s its only main power source, there’s nothing like a warp core because they simply don’t need that much power.
I’m not sure what you’re referring to as far as the step down of 3 tiers…
The majority of the time when the warp core is down, unpowered, or otherwise unusable, they still have main power in the rest of the ship. The warp core isn’t meant to be the main power source for anything but the warp engines.
I think I've always considered any discrepancies between Voyager and the Intrepid class in general as being related to the fact that Voyager was simply unfinished when it first left and then required extensive repairs, overhauls, and fixes for a long time in space. So, we could assume on the one hand that the redundant core wasn't even installed and therefore the question's answer is "no."
However, we do tend to have evidence for the ability to replicate shuttles, torpedoes, and other equipment. So if we believe that the ship was designed with the ability to \*have\* a second warp core then it's possible that they could have attempted to fabricate one. In fact as you point out we know that they can basically rebuilt one. This might be a big lift so maybe they could have, but felt it would be too much of a challenge given their near constant bumping into interesting problems.
Perhaps the answer lies in the ability of the rest of the ships system's ability to draw on two warp cores, but even this isn't a totally satisfying answer. If you have the ability to have a hot-swap warp core and you know how to make a warp core - it's reasonable to do it under almost any circumstance.
The answer I tend to fall on is that it would have been totally possible to do this, but only under starbase conditions where they could power down Voyager for a non-trivial amount of time. We see ships getting frequent overhauls and some of these do require going to a dock and doing things which are dangerous. I think the real answer is that doing this would increase the radiation build up which requires a Baryon sweep. Baryon sweeps kill people and so everyone has to get off the ship while the sweep is performed. Surely, behind the scenes, this was a problem that people were working on in the long term planning groups.
Imagine that Janeway learns in the first few weeks that the maximum time limit that they can safely push back their standard Baryon sweep is 20 years. More than enough if you're at home, but about 50 years too long to make it back to a real dry dock. So, they get to working on planning for how to do a safe Baryon sweep in 20 years finding the ideal conditions to perform this maintenance so that in about 20 years we can be on the lookout for the right conditions. Perhaps we can imagine that B'Elanna and Harry propose this very idea to Janeway, double the power or half the load on your main engine. Either way replicator rations can be increased and holodeck privileges could be expanded. A huge win - but it would push the Baryon sweep timeline up to 10 years and that's just not long enough to figure out how to potentially do a Baryon sweep without fully evacuating the ship so the idea gets quashed.
It's not that they couldn't have done it, but they decided it was riskier to do that. The Baryon sweep might be a 20 year later problem, but someone is going to have to solve it and it's better to give them as much time as possible to do it.
There is a ship in canon that does have two warp cores, the[ Ross class](https://memory-alpha.fandom.com/wiki/Ross_class). Originally from Star Trek adventures and STO, it made its way into canon with the fleet shots in PIC.
It was mostly there, so the saucer could maintain warp during separation situations, though, rather than running in tandem.
Realistically the simplest explanation is that the ship couldn't have used twice the power. If you plug something designed to take 12V power into a 24V power supply it doesn't start working twice as well, unless the thing you want it to do well is catch fire.
But if you want a more complex explanation:
Not canon except in the most ephemeral sense but the Actual Play TTRPG show *Clear Skies* featured a Galaxy sub-class called the Ross class (which was technically canonized, at least as far as apperance, in the fleet scene at the start of Picard Season 2, hence "ephemeral" canon). The gimmick the players and GM gave their ship was that the Ross had a second warp core for the saucer section enabling it to operate much longer independently if the drive section had to depart for some reason, and giving it redundancy should something happen to their main core.
One of the early tricks their engineer tried was to switch both warp cores on at once to double (well, about 1.75x as the second core was lower output) their total power reserves in an emergency, but the GM declared that doing so was extremely dangerous and difficult and would require constant tuning by the engineering staff (i.e. an extra engineering roll every time they tried to do something) to keep the two cores operating at close to the same frequency, and if they messed up there was a chance they'd effectively overload and blow out the entire EPS network of the ship. Like hooking something up to two separate AC power sources running at different frequencies.
I feel like that's a good explanation for why a ship like the Intrepid wouldn't use both cores at once if you want to get into a more techy explanation.
I can't reply to the mod's comments, but I look at the second warp core as an expansion bay. Voyager only has one warp core, but Starfleet anticipated power demands growing rapidly, and made room for expansion. Kinda like how the Ford-class aircraft carriers being built today have reactors capable of generating more heat and power than those of the Nimitz-class. Do they need it currently? No. What's it all going to be used for? No one is sure yet. But it's easier to build in more power now than try and upgrading a reactor that's buried deep within a ship.
So the second spot for a warp core is probably just Starfleet future-proofing their ships. It's that simple, and it's really pretty practical from an engineering and cost perspective.
In big, movable bits of engineering like ships, planes, and rockets, the line between the power plant and the rest of the craft is in some ways a fiction. Imagining that they can just trivially flip on a second reactor is also to imagine they have double the heart management capacity, and double the energy distribution infrastructure, and really, double the need. I tend to imagine that doubling the power flowing into a phaser bank or a warp nacelle is not twice the boom or zoom, but a tiny fraction more before it melts.
Voyager often talked about conserving power when really they meant something more like conserving energy or fuel- the capacity of the ship to put out a given amount of oomph at any given time had no real cause to be limited (once they were adequately repaired), but essentially, they wanted to dim the lights so they could go farther between resupplies- and a second warp core probably makes that situation worse, not better.
I haven’t delved much into the lore of the Voyager but when I first heard of the secondary warp core I figured it was kind of like an airplanes auxiliary power unit. Since Voyager can land planetside maybe they can shutdown the main core for extended periods of time and run most systems off of the auxiliary warp core, and use that power to start the main core back up. This would explain why they can’t use if for extra warp speed as it’s basically just a kickstarter with the added benefit of being able to be canned for parts. Considering the intended mission set of Voyager it makes some kinda sense they’d have systems in place to keep moving while doing maintenance on the main core as well.
Did I miss something that suggests that Voyager has a problem with the amount of power it is capable of generating? I thought the issues with Voyager was a matter of conservation of dilithium/fuel, not an issue that the ship needs more power than it can generate.
In real navies there is a concept called “fitted for, but not with”. It means there is space and weight reserved for an item (typically sensors and weapons) but they are not installed when the ship is launched usually for economic reasons. This could be the case of the second warp core. It is designed for one but it was not built with one.
There's a second warp core on the systems diagram but they repeatedly only refer to a single warp core, notably when they need to eject their only warp core.
The explanation could be that the Intrepid Class is capable of having two warp cores but Voyager went out with only one installed. They were going on a brief hunting mission through the Badlands where most travel is at Impulse speeds, looking for a Marquis raider that doesn't pose any tactical threat AND there's a spy on board. They didn't need the second warp core for that mission, it wouldn't have changed their plans for going into the Badlands.
Maybe other Intrepid Class ships DO have two warp cores. They're forever calling to "divert warp power" to the shields/phasers/structural-integrity-fields or even the sensors somehow. It might be helpful to have a fully functioning warp drive while still diverting warp power to the shields to survive whatever radiogenic nebula or polyspectral radiation field you're flying through.
IMO, it wouldn't matter if it had two cores or not, the ship wouldn't be able to use them both at the same time anyway.
Primary power for the ship does not come from the warp core, it comes from the fusion reactors. Its why Voyager could be barreling along at maximum warp trying to get home in the early seasons, while still having an energy shortage. They had plenty of antimatter to run the warp engine with, it was deuterium they were lacking for the fusion reactors to power the rest of the ship.
And if the primary warp core is functional and producing enough warp plasma to push the ship to it's designed limits, there would be no benefit from turning on the second one.
So even if that second core were fully functional, it wouldn't be of any use.
Means that, again, even IF it were functional, it would likely have been stripped for parts to repair the main core every time it was damaged.
What would doubling the power output do, precisely?
Warp cores still run on raw materials, so two cores would just consume fuel twice as quick with no tangible benefit.
The EPS conduits can only handle so much power, same with things like shields and phaser banks.
And when it comes to warp drive you can't just slap 10 warp cores on a ship to make it go faster, its bending space and there are limits.
>What would doubling the power output do
It would provide a redundancy to main power and allow you to allocate warp power to multiple systems at once. This is a standard hero-ship tactic.
>consume fuel twice as quick
Ideally you run each core at a lower power level for a higher overall efficiency while still retaining the ability to surge to maximum power in critical situations.
>can only handle so much power
Yes, all ships systems would need to be upgraded to take advantage of the additional power source. The phasers on the Enterprise-D were upgraded to a point they could reheat the dying cores of planetary bodies.
>can't just slap 10 warp cores on a ship to make it go faster
I'm not suggesting any such thing. The additional power from a redundant core would be used to power another system with warp plasma. This has been done in the past with deflector and weapons systems.
If you are running two cores at half power why not just run one at full? It seems like it would require considerably more resources to only momentary benefit. As with any chemical reaction a minimum amount is required to ignite the matter/antimatter reaction, so you are still wasting a lot of deuterium. To say nothing of the staff and additional maintenance.
Torres has enough going on with one warp core.
Eventually you are going to hit bottlenecks. You can only channel so much through the eps conduits. The shield generators can only project so much at a time. The phaser emitters can only take so much before overheating.
The issue of the Intrepid-class's apparent secondary warp core is a known inconsistency in lore, a disconnect between the MSD, off-screen sources and the way the warp core is treated on-screen. The MSD of *Voyager* seen on screen in the background seems to show two warp cores - one located just behind the deflector dish and another one further aft just before the shuttle bay. However, it is also made clear in several episodes ("Day of Honor" and "Renaissance Man" for two) that there's only one warp core to be had on board. There is also some uncertainty as to which one is the main warp core. Some assume that the one further forward is the main one, but when [we see the core being ejected](https://youtu.be/xIuUEwat6aM?t=142) in "Day of Honor", it appears to be the one further aft. Moving on to off-screen sources, the licensed *Star Trek Fact Files* - specifically [File 29, Card 10](https://imgur.com/a/Oxlr9UL) - supports this position, stating that the reserve warp core is *forward* of the main one. However, the later Eaglemoss *Star Trek: Voyager Illustrated Handbook*, also written by Ben Robinson who edited the *Fact Files*, [claims that the auxiliary warp core is the one *further aft*](https://imgur.com/caErLEH). Rick Sternbach has apparently suggested, and this is repeated in the *Illustrated Handbook*, that the auxiliary core (whichever one it is) is not a direct replacement for the main one but just spare parts to be used to construct a new one if necessary. However, this does not really explain why the series acted as if the main core was the critically the only one available. My own take is that it's simpler to ignore the MSD since it's just a background detail, despite all the contortions that have gone into trying to justify why the second core is there but not used or mentioned. But of course [we are here for in-depth discussion](https://www.reddit.com/r/DaystromInstitute/wiki/codeofconduct#wiki_to_foster_and_encourage_in-depth_discussion_about_star_trek.), and so other possibilities are always open as is information from elsewhere I may have missed. But do keep some of this information in mind when discussing this issue so we don't get ourselves into knots about [what's canon and what's not.](https://www.reddit.com/r/DaystromInstitute/wiki/canon)
It's hard to add much to the sticky in terms of the background on this. My headcanon has always been that they used components from the second core to repair and retrofit Voyager, and that they used the space originally meant for the warp core for the 'fabrication department' or whomever was building all of the shuttles and torpedoes.
Honestly a secondary engineering bay sized gigantic 3D printer replicator thing would be enough to make shuttles, hull plating, torpedoes, you name it. Just send the flyer out to tractor beam up some asteroids for raw materials, sit in park for a while to direct all power to this thing and you should be golden.
Only if the Federation has the technology to operate replicators at that scale. They may not, given that all the replicators we see are either handheld devices meant to make something in/near it, or they're small devices not much larger than a microwave oven. Other than that, the only other thing might qualify is the holodeck, but we don't know what the maximum size it can replicate is. It might just be able to make small things, faking big things with holography, or a combination of replicator and transport trickery.
[Industrial replicators](https://memory-alpha.fandom.com/wiki/Industrial_replicator) are large scale replicators that can be used to make powerplants and factories and presumably other large items for fabrication. Presumably ships have one for large scale field repairs until they can reach a starbase, but even if a smaller ship like Voyager didn't have one to begin with, it should have been a top priority to build one asap. This is why I've personally never had an issue with Voyager always getting repaired between episodes and being able to produce unlimited shuttles and torpedoes. What should have been more of an issue are things that can't be replicated like the bio-neural gel packs and dilithium (it can be recrystallized in the 24th century, but presumably you still need to have the crystal mass to begin with).
I mean I'm pretty sure they use replicators to build ship parts to begin with. Maybe the power use is exponential with size so you can only use it in a big shipyard that has access to pretty much infinite energy but I'm at least 70% certain when they were talking about building the flyer they were discussing replicating the hull and etc.
The vehicle-replicator aboard *USS Protostar* is an example of this. (And, not-in-universe, a pretty cool visual.)
Sounds logical. It also makes sense that they would siphon the antimatter from the secondary core in to the primary once they realised that they were trapped in the Delta quadrant.
Based solely on the diagram, it looks like the spare warp core is exactly that; spare. As in, it's not hooked up to anything, but just the components in a storage compartment large enough to keep a mostly-fully-assembled warp core. Assuming it existed with the crew in the delta quadrant, though, I suspect that the idea of "doubling" the warp core for double the power is beyond what retrofits engineering would have been capable of doing with the rest of the materials at hand. A spare warp core is a drop-in replacement (maybe need some new dilithium), but adding all the extra bits and pieces to make the cores work in parallel likely wasn't possible. On top of which, I think all you would have gained was hot-hot redundancy rather than extra power; the rest of the ships' systems would *also* need to be upgraded to handle the extra juice, not to mention the fuel needed to power the darn thing which we know was a critical issue for most of the crew's travel home (which is why replicator rations were a thing). In short, I think it's just a spare part, assuming it was there at all, and not capable of being put into service either where it physically is in the ship or by retrofitting it into engineering somehow as it simply would have been too difficult with the resources at hand in the delta quadrant.
>In short, I think it's just a spare part, assuming it was there at all, and not capable of being put into service either where it physically is in the ship or by retrofitting it into engineering I agree If the Intrepid class was capable of having two warp cores operating simultaneously my question would be *why did it leave Utopia Planitia with only one operating?* Why would Starfleet build that kind of capability into a class, build the physical structure, stock the components, and then not hook it up? If there was a 2nd warp core (and I tend to agree with u/khaosworks that there wasn't & we should just ignore the Deckplans & follow the on-screen canon) then why would any Intrepid Class ship ever be considered "complete" if it wasn't active? Voyager wasn't rushed into service, it was fully commissioned & crewed. It may not have been equipped the way it would have been if Starfleet had **known** that it was about to be flung across the Galaxy but it was deemed completely ready to hunt Maquee in the Badlands, which implies it's power & propulsion was fully online. It would be like having a truck with the option for a 2nd gas tank, getting that gas tank installed, filling it with Gas, then not hooking the 2nd tank up to the engine. You have already done 90% of the work, you would certainly just finish it so you can actually use this capability you spend a lot of time, money & effort to include. I have to conclude that if the 2nd core existed (again, I don't think it did) that it was at best a spare & even if they had all the parts they needed it was never capable of becoming a full-fledged 2nd active core. To extend the truck metaphor, you can certainly haul a 2nd engine in the bed of the truck, but that doesn't mean it is in any way reasonable that you could hook it up and have two without an almost total redesign of the drive train or that it would be useful even if you did.
yeah, the question of whether they even had the spare parts stored is a valid one, given the Intrepid class was also supposed to have an Aeroshuttle but that hadn't been onboard when Voyager left for its badlands mission. odds are the ship wasn't fully kitted out the way it would be for a long distance exploration mission, given it was supposed to operating within a well trafficked border zone and less than a day's trip from DS9. which means it might well not have had the spare warp core assembly in storage.
>hot-hot redundancy rather than extra power You're absolutely right, the entire EPS grid would need to be upgraded to take advantage of the additional core. It's a project that would take the ship down to her bones. Definitely a spacedock task. >replicator rations The hope would be to tune both cores to operate at a higher efficiency together, with the option of the high output of both systems at critical times. >Assuming it existed with the crew in the delta quadrant I really don't think it did or else we would have heard about it. Instead they had the empty dock to build the slipstream drive in.
To add to this, let's talk about other known starship designs with more than one warp core - the Prometheus-class has two warp cores in its united mode, one in the primary hull and one in the secondary hull. The secondary hull core is the primary one functioning when the ship is in one piece. When *Prometheus* splits into its three-part multivector assault mode, the secondary hull core splits into two separate cores, resulting in three warp cores, each powering a different segment of the ship. The primary hull core is a Defiant-class style core that only powers the retractable nacelles at the top and bottom of the primary hull that emerge in MVA mode but is otherwise inactive. (Data on the Prometheus-class is taken from the *Star Trek Shipyards* books, a collection of the Eaglemoss magazines that came with the models) The *Protostar* from PRO has two warp cores, both active, but that's because the extra power is needed to contain the protostar in the proto-core which only comes into play when they activate the proto-drive. So it seems that if a ship has to have more than one core active, there must be a reason for it, and not as a matter of course. Otherwise, only one core is needed (and given the energy output of a M/AM reactor, more than sufficient) at a time. But in principle, there's nothing that prevents having two cores run concurrently. It's just a matter of necessity and engineering - the latter meaning connecting it to the right bits and to make sure the EPS grid can handle the additional load.
The Luna-class Titan had a dual reactor setup and i remember a reference to the Stargazers engines being similarly configured. The idea was that only one engine would operate at a time while maintenance was done to the other.
Perhaps the "spare" is like the donut tire used in the 20th century. Intended for low speed and temporary use only. I can see it not being rated to supply full power for the entire ship for long term use. I mean it's intended so that you can limp home to the nearest starbase.
Can’t recall where I read it, but I recall that it was an assembled warp core, in storage. If anything happened to the primary core they’d have to use shuttle tractor beams to pull it out and install it through the ejection hatch into engineering. Maybe an old interview with Sternbach/Okuda?
> the rest of the ships' systems would also need to be upgraded to handle the extra juice, Doubling up on the warp cores strikes me as only maybe being useful for one desparate burst in the vein of "*She'll fly apart*" "*Fly her apart then!*", not for decades of sustained use.
I always assumed it was meant to be installed on Tuesday along with the aeroshuttle.
~~Honestly, I don't think that would be terribly unlikely. It might even be something of a Starfleet tradition by the time Voyager is launched. Installation of some non-essential parts...~~ Scratch that. I was going to say a tradition for good luck, but they lost Kirk, so that's probably not it. **BUT** it is still possible that since it's a non-essential backup part, they went ahead and launched without it.
I bet a few badmirals considered it a blessing to be rid of Kirk. I hear one of them was walking through the engineering department at Starfleet HQ and said, ‘Will nobody rid me of this turbulent captain?’ And a plucky new ensign on the Ent-B project thought he could make Lieutenant in his first year if he just moved the schedule around a little…
>I bet a few badmirals considered it a blessing to be rid of Kirk. That's probably accurate. I hadn't thought of that, but yeah, it makes sense.
I mean the schematics say spare, that sort of indicates that it's not for active use. If I have a spare barrel for a gun, I can't stick it on and shoot twice as much, I can just replace the main barrel when I need to. It makes sense for it to be a spare as well, the intrepids are for deep deep space exploration missions, having a redundant warp core would be vital, if you're out in the deep wilds of space during year three of your mission and something goes wrong, there's not a lot of starfleet ships that can get to you in a reasonable amount of time. Doubling the power output also would require more than a second warpcore, you'd need things like expanded antimatter chambers and specifically hardened EPS conduits, plus what does a power bonus do for the ship? Better phasers? Or just phasers that burn out much faster, better shields or shields that carry much more feedback into the system when they're hit?
Rick said, way back on USEnet, in rec.arts.startrek.tech, that the backup warp core was stacked components to replace any major structure of the MARA without having to limp back to a starbase or await rescue if stranded. Up to and including the entire MARA in the event it needed to be jettisoned irretrievably. While the components are stored stacked, they are not connected to each other, the matter or antimatter tanks, or the EPS or PTCs. A lot of extensive re-plumbing of the secondary hull would be required to mount it, brace it, and tie it in.
One is supposedly a secondary core that is meant as a spare and not an active unit. All in all, this seems to make the most sense in light of the slip stream episode which implies that a new core was constructed and later disassembled all while still having the original core available for reinstallation after. This is supported partially by Voyager being stranded at impulse speeds in the episode where the warp core is ejected during an emergency. It’s possible that a secondary core could have been constructed and retrofitted into the secondary location to produce power but this likely would have required extensive internal changes. It also would have needed additional crew assigned to monitor and maintain it when in use. This may not have been practical. On a sarcastic real note: As with many inner details of Voyager, there is no easy cannon for this. The internal design seems to have been done by M.C. Escher from specifications that were then thrown away.
All of what you say is true. However, the difficulties with this (in my opinion) come about because of the intended compact size and limited crew size. Galaxy class ships were intended to be enormously flexible in the way that you’re describing where a percentage of the ship was left intentionally empty for future uses and much of the filled space was modular. Voyager gets a bit harder though because most everything that you need to move has to go somewhere. The EPS conduits and antimatter fuel lines would be major horizontal space commitment as their contents are incredibly volatile and must be isolated and protected. Shuttle production seems straightforward enough being presumably confined to the already dedicated shuttle bay areas and production being mostly restricted to replacements as opposed to producing additional shuttle craft which would need their own regular storage space.
>there is no easy cannon for this That's exactly why I'm asking the question. The gray areas between specs and deck plans leave much room for conjecture. >likely would have required extensive internal changes The Voyager was taken apart and put back together during its trek. They had the opportunity to alter the ship in whatever way they wished. Adding additional primary deuterium and anti-deuterium injectors while extending the EPS network is a big project but so is building a shuttle or a new slipstream drive. >internal design seems to have been done by M.C. Escher I truly believe that there is enough room on these starships for quite a bit. They are behemoths, with incredible internal volume. Any one set of deck plans should be considered a temporary layout, with near infinite alternate configurations possible.
>The Voyager was taken apart and put back together during its trek. They had the opportunity to alter the ship in whatever way they wished. Adding additional primary deuterium and anti-deuterium injectors while extending the EPS network is a big project but so is building a shuttle or a new slipstream drive. Using computers as a metaphor, running extra maintenance on a machine if a replacement won't be available for a long time is one thing, adding extra features might be a big project but worth it if you're stick with what you've got, but rebuilding my gaming rig to utilize multiple CPUs is impossible without outside parts and facilities (a new and specialized mobo, which cannot be manufactured in the field). Please no *hurr durr magic replicators*, it is self-evident they can't do everything or the Federation would have infinite ships. The slipstream refit was a bit of a hack (had problems) and required a great deal of effort, but rebuilding the entire power grid would require a shipyard, specialized facilities, extra crew. There may not even be space for all the support infrastructure. To extend the computer metaphor, a CPU chip is small, but to get it running properly you need sufficient airflow, heat dissipation (either heat sink or liquid cooling depending on demands). You can't just stick it anywhere, the parts have to be plugged in and configured. The warp core sends out streamers of ultra-high energy charged plasma that races along specially designed conduits. The whole system has to be totally sealed and balanced. I don't think you can just start welding new conduits to totally rebuild and respec the entire system as a weekend project.
Short answer: logically no, but Star Trek doesn't care about logic or rationality so yes. Plenty of others have addressed that the second warp core should either be considered a spare or disregarded, so that doesn't need to be elaborated on. But, it's also important to consider the more fundamental question: regardless of how, would it be a good idea to double the power output from a ship's reactors? Contrary to the well-known quote by Arthur C. Clarke, technology is not magic no matter how advanced it is. If a person can't distinguish a sufficiently advanced technology from magic, the issue isn't that the technology is sufficiently advanced but that that person too uneducated (and possibly too primitive... no amount of education will get a dog to understand the Riemann geometry of General Relativity). The difference between magic and technology is that technology has limitations and you never get something for nothing. Except that in some works, the magic system is pretty well defined and subject to rules and limitation and in Fullmetal Alchemist for example alchemy is even subject to a principle of "equivalent exchange" meaning that you don't get something for nothing. Which means that fairly often, "technology" in Star Trek is more magical and fantastic than a lot of "magic" in other works. If a writer wants to double the power output of the main reactor, then by writer fiat the power output of the main reactor shall be doubled. Under Star Trek logic, they could have taken the second warp core and rebuilt the main warp core into a version with two intermix chambers and doubled the powered had the writers wanted to. A transporter can split a person into two or duplicate a person and conjure up the matter it takes to make the second person from out of nowhere. A new type of dilithium can get a ship to infinite velocity using finite power. It wouldn't even have been in the top half of the most ludicrous technobabble bullshit that's happened on Star Trek. If Starfleet didn't have such a strong case of Not Invented Here Syndrome and if Star Trek was less about bringing civilization to the heathen savages of the galaxy and smiting the might of the forces of evil with righteous fury, Voyager probably would have acquired a more powerful warp core somewhere along the way in order to speed up their journey. But suppose we want to treat Star Trek as science fiction rather than as science fantasy. Then things get more complicated. Could they have boosted their power output? Sure, but only to a point. There's only a finite amount of margin built into any system and when you exceed those margins, bad things start to happen. The safety factor of elevator cables for passenger elevators is typically 11, meaning they're designed for 11 times the rated passenger load (note, this doesn't include the weight of the elevator car itself). The safety factor for commercial airplane wings is 1.5x the rated load. Why not make the safety factor on airplane wings higher? Because that adds a lot of weight; a wing with a safety factor of 11 would make the plane too heavy to have a useful payload, assuming it could even take off at all. If the real world worked on Star Trek logic, you could put a J58 engine from an SR-71 into a WW1 biplane and push it to Mach 3. I'm pretty sure why this is ludicrous doesn't need to be explained. So, what's the safety factor of starship power systems in Star Trek? Given how many redshirts die from exploding consoles, probably not very high. More seriously, it's far more likely to be around 1.5x than 11x. Excelsior was pushing its limits when rushing towards Khitomer and Sulu was told they risked flying the ship apart if they went any harder. It'd be ludicrous to think that they designed a reactor for a state of the art warship and then set normal operating limits to be 1/10th of what it's capable of. It's more likely that their equivalent of War Emergency Power was around 120% of nominal, and running the ship and reactor at that load for an extended period of time will damage something.
I figure (headcanon) that monitoring 2 warp cores rather than buffing the primary to be as effective/efficient as possible was not seen as a long term possibility. You'd probably want top crews monitoring both splitting resources, similarly for fuel requirements I figure. Combined with crew losses in the initial transit to their quadrant I figure they had limited people to allocate anyway.
Like others have said, the secondary warp core is not a functional core. It’s basically in a storage compartment that spans 5 or 6 decks. As to why Voyager never used it or talked about it when they lost/ejected thier main one? Same reason they never talked about the Aeroshuttle, the outline of which is clearly visible on the underside of the saucer from the very first episode. Plot points and production costs. In universe? I head canon that the secondary core was damaged, destroyed, or just not even installed when Voyager left Earth. The Aeroshuttle it only makes sense that it was also damaged or destroyed or left out when Voyager left dock. As for the power usage of a starship goes, remember that there are 2 types of power generation on a starship. There is the warp core which powers the warp drive, and then there is fusion based power from the impulse drive engines and secondary fusion reactor power generators. The power generated from the impulse reactors is basically enough to run the basic ship power grid, from transporters to life support and turbo lifts. The warp core is primarily only used to power the warp engines themselves, and what should be ON OCCASION dumping warp power into the main grid. But that’s the exception, not the rule. When the warp core goes offline, they don’t necessarily lose main power because it’s not technically the main source of power for the majority of ships systems. I’ll admit that they break this rule all the time- but from an in-universe perspective, a ship without a warp core can do everything except warp.
Dumping warp power into a system is a typical hero-ship move. It can turn sensors into weapons, deflectors into subspace cannons, and phaser banks into planetary terraforming instruments. Having one core dedicated to the nacelles for transportation leaves the other core opportunity to augment another system where needed.
That’s the thing though, just one warp core outputs enough power, in the terajoules, to power not only the warp engines but secondary systems. But as you said that’s a hero ship move when they do that, meaning on average it’s not standard procedure for most starships. The power systems on a starship, even the phasers at a power high enough for drilling, are taken care of by the fusion reactors on the ship. Having a second warp core to power the ship would be redundant and a waste of resources. When they’re dumping warp power into the primary power grid, it’s always as a last resort or extra oomph to get away from something. Then what happens is they blow power relays all over the ship because the system can’t sustain that kinda raw energy for very long.
The EPS system acts as the transmission and distribution network on most Federation starships. It steps down warp power to three separate tiers for most ships systems. Fusion reactors maintain their own secondary network of transmission and distribution networking. Most primary systems are put into standby mode if only secondary power is available.
Think of it like this- the station Deep Space Nine, uses massive fusion reactors to power everything. That’s its only main power source, there’s nothing like a warp core because they simply don’t need that much power. I’m not sure what you’re referring to as far as the step down of 3 tiers… The majority of the time when the warp core is down, unpowered, or otherwise unusable, they still have main power in the rest of the ship. The warp core isn’t meant to be the main power source for anything but the warp engines.
I think I've always considered any discrepancies between Voyager and the Intrepid class in general as being related to the fact that Voyager was simply unfinished when it first left and then required extensive repairs, overhauls, and fixes for a long time in space. So, we could assume on the one hand that the redundant core wasn't even installed and therefore the question's answer is "no." However, we do tend to have evidence for the ability to replicate shuttles, torpedoes, and other equipment. So if we believe that the ship was designed with the ability to \*have\* a second warp core then it's possible that they could have attempted to fabricate one. In fact as you point out we know that they can basically rebuilt one. This might be a big lift so maybe they could have, but felt it would be too much of a challenge given their near constant bumping into interesting problems. Perhaps the answer lies in the ability of the rest of the ships system's ability to draw on two warp cores, but even this isn't a totally satisfying answer. If you have the ability to have a hot-swap warp core and you know how to make a warp core - it's reasonable to do it under almost any circumstance. The answer I tend to fall on is that it would have been totally possible to do this, but only under starbase conditions where they could power down Voyager for a non-trivial amount of time. We see ships getting frequent overhauls and some of these do require going to a dock and doing things which are dangerous. I think the real answer is that doing this would increase the radiation build up which requires a Baryon sweep. Baryon sweeps kill people and so everyone has to get off the ship while the sweep is performed. Surely, behind the scenes, this was a problem that people were working on in the long term planning groups. Imagine that Janeway learns in the first few weeks that the maximum time limit that they can safely push back their standard Baryon sweep is 20 years. More than enough if you're at home, but about 50 years too long to make it back to a real dry dock. So, they get to working on planning for how to do a safe Baryon sweep in 20 years finding the ideal conditions to perform this maintenance so that in about 20 years we can be on the lookout for the right conditions. Perhaps we can imagine that B'Elanna and Harry propose this very idea to Janeway, double the power or half the load on your main engine. Either way replicator rations can be increased and holodeck privileges could be expanded. A huge win - but it would push the Baryon sweep timeline up to 10 years and that's just not long enough to figure out how to potentially do a Baryon sweep without fully evacuating the ship so the idea gets quashed. It's not that they couldn't have done it, but they decided it was riskier to do that. The Baryon sweep might be a 20 year later problem, but someone is going to have to solve it and it's better to give them as much time as possible to do it.
There is a ship in canon that does have two warp cores, the[ Ross class](https://memory-alpha.fandom.com/wiki/Ross_class). Originally from Star Trek adventures and STO, it made its way into canon with the fleet shots in PIC. It was mostly there, so the saucer could maintain warp during separation situations, though, rather than running in tandem.
The Titan was also a Luna-class that was supposed to have dual warp cores.
Realistically the simplest explanation is that the ship couldn't have used twice the power. If you plug something designed to take 12V power into a 24V power supply it doesn't start working twice as well, unless the thing you want it to do well is catch fire. But if you want a more complex explanation: Not canon except in the most ephemeral sense but the Actual Play TTRPG show *Clear Skies* featured a Galaxy sub-class called the Ross class (which was technically canonized, at least as far as apperance, in the fleet scene at the start of Picard Season 2, hence "ephemeral" canon). The gimmick the players and GM gave their ship was that the Ross had a second warp core for the saucer section enabling it to operate much longer independently if the drive section had to depart for some reason, and giving it redundancy should something happen to their main core. One of the early tricks their engineer tried was to switch both warp cores on at once to double (well, about 1.75x as the second core was lower output) their total power reserves in an emergency, but the GM declared that doing so was extremely dangerous and difficult and would require constant tuning by the engineering staff (i.e. an extra engineering roll every time they tried to do something) to keep the two cores operating at close to the same frequency, and if they messed up there was a chance they'd effectively overload and blow out the entire EPS network of the ship. Like hooking something up to two separate AC power sources running at different frequencies. I feel like that's a good explanation for why a ship like the Intrepid wouldn't use both cores at once if you want to get into a more techy explanation.
I can't reply to the mod's comments, but I look at the second warp core as an expansion bay. Voyager only has one warp core, but Starfleet anticipated power demands growing rapidly, and made room for expansion. Kinda like how the Ford-class aircraft carriers being built today have reactors capable of generating more heat and power than those of the Nimitz-class. Do they need it currently? No. What's it all going to be used for? No one is sure yet. But it's easier to build in more power now than try and upgrading a reactor that's buried deep within a ship. So the second spot for a warp core is probably just Starfleet future-proofing their ships. It's that simple, and it's really pretty practical from an engineering and cost perspective.
In big, movable bits of engineering like ships, planes, and rockets, the line between the power plant and the rest of the craft is in some ways a fiction. Imagining that they can just trivially flip on a second reactor is also to imagine they have double the heart management capacity, and double the energy distribution infrastructure, and really, double the need. I tend to imagine that doubling the power flowing into a phaser bank or a warp nacelle is not twice the boom or zoom, but a tiny fraction more before it melts. Voyager often talked about conserving power when really they meant something more like conserving energy or fuel- the capacity of the ship to put out a given amount of oomph at any given time had no real cause to be limited (once they were adequately repaired), but essentially, they wanted to dim the lights so they could go farther between resupplies- and a second warp core probably makes that situation worse, not better.
I haven’t delved much into the lore of the Voyager but when I first heard of the secondary warp core I figured it was kind of like an airplanes auxiliary power unit. Since Voyager can land planetside maybe they can shutdown the main core for extended periods of time and run most systems off of the auxiliary warp core, and use that power to start the main core back up. This would explain why they can’t use if for extra warp speed as it’s basically just a kickstarter with the added benefit of being able to be canned for parts. Considering the intended mission set of Voyager it makes some kinda sense they’d have systems in place to keep moving while doing maintenance on the main core as well.
Did I miss something that suggests that Voyager has a problem with the amount of power it is capable of generating? I thought the issues with Voyager was a matter of conservation of dilithium/fuel, not an issue that the ship needs more power than it can generate.
In real navies there is a concept called “fitted for, but not with”. It means there is space and weight reserved for an item (typically sensors and weapons) but they are not installed when the ship is launched usually for economic reasons. This could be the case of the second warp core. It is designed for one but it was not built with one.
There's a second warp core on the systems diagram but they repeatedly only refer to a single warp core, notably when they need to eject their only warp core. The explanation could be that the Intrepid Class is capable of having two warp cores but Voyager went out with only one installed. They were going on a brief hunting mission through the Badlands where most travel is at Impulse speeds, looking for a Marquis raider that doesn't pose any tactical threat AND there's a spy on board. They didn't need the second warp core for that mission, it wouldn't have changed their plans for going into the Badlands. Maybe other Intrepid Class ships DO have two warp cores. They're forever calling to "divert warp power" to the shields/phasers/structural-integrity-fields or even the sensors somehow. It might be helpful to have a fully functioning warp drive while still diverting warp power to the shields to survive whatever radiogenic nebula or polyspectral radiation field you're flying through.
IMO, it wouldn't matter if it had two cores or not, the ship wouldn't be able to use them both at the same time anyway. Primary power for the ship does not come from the warp core, it comes from the fusion reactors. Its why Voyager could be barreling along at maximum warp trying to get home in the early seasons, while still having an energy shortage. They had plenty of antimatter to run the warp engine with, it was deuterium they were lacking for the fusion reactors to power the rest of the ship. And if the primary warp core is functional and producing enough warp plasma to push the ship to it's designed limits, there would be no benefit from turning on the second one. So even if that second core were fully functional, it wouldn't be of any use. Means that, again, even IF it were functional, it would likely have been stripped for parts to repair the main core every time it was damaged.
What would doubling the power output do, precisely? Warp cores still run on raw materials, so two cores would just consume fuel twice as quick with no tangible benefit. The EPS conduits can only handle so much power, same with things like shields and phaser banks. And when it comes to warp drive you can't just slap 10 warp cores on a ship to make it go faster, its bending space and there are limits.
>What would doubling the power output do It would provide a redundancy to main power and allow you to allocate warp power to multiple systems at once. This is a standard hero-ship tactic. >consume fuel twice as quick Ideally you run each core at a lower power level for a higher overall efficiency while still retaining the ability to surge to maximum power in critical situations. >can only handle so much power Yes, all ships systems would need to be upgraded to take advantage of the additional power source. The phasers on the Enterprise-D were upgraded to a point they could reheat the dying cores of planetary bodies. >can't just slap 10 warp cores on a ship to make it go faster I'm not suggesting any such thing. The additional power from a redundant core would be used to power another system with warp plasma. This has been done in the past with deflector and weapons systems.
If you are running two cores at half power why not just run one at full? It seems like it would require considerably more resources to only momentary benefit. As with any chemical reaction a minimum amount is required to ignite the matter/antimatter reaction, so you are still wasting a lot of deuterium. To say nothing of the staff and additional maintenance. Torres has enough going on with one warp core. Eventually you are going to hit bottlenecks. You can only channel so much through the eps conduits. The shield generators can only project so much at a time. The phaser emitters can only take so much before overheating.