Possible improvements to Navani's flying fabrials.

[Through The Living Grub He/Him]

These are a couple of ideas that I came up with that could be used to improve Navani's plane fabrials, and I thought they might be fun to share.

First: How these fabrials work.

Conjoined gemstones are attached to the ship and a "controller" for lack of a better term. The controller is moved in a desired direction with a specific velocity for a period of time, and then spanreeds are used to coordinate the next action. Aluminum is used to "isolate planes of motion" which presumably means the ship can only move in straight lines without drifting to one side. Relatively simple, but labor intensive and requires a lot of awkward communication.

Improvements:

1. In the chapter heading of ROW ch. 13, Navani says (in her lecture on fabrials) that some spren "do not split as evenly, as easily, or at all" when compared to flamespren. My theory is that this uneven split will have an effect similar to having a spren in gemstones of different size gemstones: energy is conserved causing one gem to move a greater/smaller distance proportional their difference in size.

2. Similar to 1 but more focused on the actual constructed fabrials. I do not know what they do in world, but in theory the controller fabrials can have gemstones packed closer together and built out of a much heavier material. You end up with different velocities despite the size/mass difference.

I have vague ideas on how spanreed communication could be improved, but no way to describe it, and I lack understanding of how aluminum could be used. They should probably just invent Morse Code to be honest.

Any thoughts?

[Through the living Wahr He/Him]

I think the biggest Improvement of the Airship would need the discovery/rediscovery of a theoretically possible but not yet seen Surge Fabrial:

Gravitation Fabrial

We do not know how exactly they work, but they would utilize the Surge of Gravitation, if we look at other Surge Fabrials, we can assume they would be used similarly to the Radiant use of Surges. So theoretically they could be used to lashe an Object in any direction.

[PanLin they/he]

16 hours ago, Through The Living Grub said:

Conjoined gemstones are attached to the ship and a "controller" for lack of a better term. The controller is moved in a desired direction with a specific velocity for a period of time, and then spanreeds are used to coordinate the next action. Aluminum is used to "isolate planes of motion" which presumably means the ship can only move in straight lines without drifting to one side. Relatively simple, but labor intensive and requires a lot of awkward communication.

I mean, not necessarily—move the horizontal controller in a curve and the Bridge will follow that curve. Having the two controllers always reminded me of a video game controller or an Etch A Sketch. Precise control comes from coordinating the movements of the two controllers (but yes, I'll grant you that the controllers for the Bridge are slightly bigger than an Etch A Sketch).

 

16 hours ago, Through The Living Grub said:

1. In the chapter heading of ROW ch. 13, Navani says (in her lecture on fabrials) that some spren "do not split as evenly, as easily, or at all" when compared to flamespren. My theory is that this uneven split will have an effect similar to having a spren in gemstones of different size gemstones: energy is conserved causing one gem to move a greater/smaller distance proportional their difference in size.

I really had a good look around before posting this, so I hope I'm not saying something that's already be suggested, but I wonder if brass on the controller or zinc on the Bridge's lattice could be used to amplify the distance travelled (presumably by either requiring more Investiture, making the controller harder to move like upshifting on a bicycle, or both). Or maybe they would just make the conjoinment more efficient over larger distances?

Could just be that duralumin has a similar effect on Fabrials as it does on Allomancy, but we might not know for a while—Vin kind of accelerated the technological development of aluminum and its alloys because she knew there was a new alloy that would be allomantically viable, which isn't a push we have on Roshar (unless someone like Nirvani makes the observation that Fabrial metal effects tend to come in alloy-pairs).

That said, I like your idea too, and it makes intuitive sense—the chunk with less living Investiture in it moves further compared to the larger chunk.

Would be handy to find a way to make asymmetrical conjoiners that doesn't require Raysium, too (heck, maybe copper could do a similar thing).

 

16 hours ago, Through The Living Grub said:

2. Similar to 1 but more focused on the actual constructed fabrials. I do not know what they do in world, but in theory the controller fabrials can have gemstones packed closer together and built out of a much heavier material. You end up with different velocities despite the size/mass difference.

Yeah, sounds like a different packaging of the same concept. I think the main limiter here would be how much more difficult it gets to move the controllers. They seem to operate like gearboxes, so it's always going to be a balance between distance and force (unless they find a way to fuel the movement with Investiture instead).

 

16 hours ago, Through The Living Grub said:

I have vague ideas on how spanreed communication could be improved, but no way to describe it, and I lack understanding of how aluminum could be used. They should probably just invent Morse Code to be honest.

Anything you want to just wordvomit on and then work out later? We have seen a sort of rudimentary blinking code used on spanreeds a few times—I think the closest to Morse code was in Dawnshard after Huio stumbles on his aluminum discovery, but I don't have that book on me rn to check.

 

5 hours ago, Through the living Wahr said:

Gravitation Fabrial

We do not know how exactly they work, but they would utilize the Surge of Gravitation, if we look at other Surge Fabrials, we can assume they would be used similarly to the Radiant use of Surges. So theoretically they could be used to lashe an Object in any direction.

Well that's going to be handy for spaceflight 

Even for normal airflight, imagine being able to fully negate any gravitational pull on an aircraft, leaving the pilot able to freely navigate in three dimensions.

 

As for my input, I would LOVE to know how the other allomantic metals interact with Fabrials. Stuff like:

• can cadmium be used to change a Fabrial's local perception of time, to account for time dilation? (especially as the Cosmere enters the space age, the ability to track time in specific locations by letting some clocks on your ship ignore the time dilation experience by the ship is HUGE)
• is there more to aluminium, based on its actual allomantic effect? Is there a way to use its interactions with Identity to either unkey any incoming Investiture or blank a Fabrial spren's Identity, to allow it to use any Light, or even Breaths or Hion?
• can electrum allow a Fabrial to self-adjust and predict things without it needing to be Awakened?

Not going to go through all of them, but there's a lot of potentially fun realmatic engineering waiting to be unlocked there.

[Jult]

There's so much room for improvement. It requires hundreds of laborers turning winches to move vertically and dozens of chulls to move laterally. At full speed, it goes about 5 knots (9.26km/h or 5.75mph). It also takes hundreds of infused gems to power. 

Certainly, Navani's discovery of using Raysium to transfer conjoined spren into different sized gemstones will cut down on the amount of labor required to get the ship moving and increase its speed.

Though, I think, to save on Stormlight, I'd probably scrap a good chunk of the design related to lateral movement and build something more similar to Rysn's freechair. Keep the winch system (but enhanced with different sized gemstones) for vertical movement because that's the part that kind of requires magic to work. And find a new way to "push" the ship around laterally without consuming Stormlight. Some of Navani's earlier sketches had sails and by RoW they had added fans (though they were barely functioning)... That's a good step in this direction. Or just get your hands on some Aether spores, but that doesn't feel super possible for present-day Roshar.

As for communication... The gems discovered in the Urithiru gem archive already introduced something similar to Morse code, so they do have a blueprint for that. But I also think that Navani's work with tones and vibrations in RoW was already inching towards some kind of walkie-talkie fabrial. Some kind of paired conjoiner fabrials that pass along vibrations to produce tones.

[Qianweilian He/him]

7 minutes ago, Jult said:

It requires hundreds of laborers turning winches to move vertically and dozens of chulls to move laterally.

Honestly, even just motors and engines would help a lot.

[PanLin they/he]

5 minutes ago, Qianweilian said:

Honestly, even just motors and engines would help a lot.

And at that point, it probably is more efficient to just mount some steam-powered propellers on the Bridge and only use the conjoiners for vertical movement.

[ParaTulip fae/faer (declines as she/her)]

36 minutes ago, PanLin said:

And at that point, it probably is more efficient to just mount some steam-powered propellers on the Bridge and only use the conjoiners for vertical movement.

Have we seen anyone do steam power using flame-spren? Coal and fuel oil are not things that I recall coming up in the Stormlight books, running a steam engine on charcoal sounds like a bad time logistically, and I almost wonder if using attractor and repeller fabriels would not be a better system?

Doing a power conversion from Light to Spren to Water to Steam to Kinetic Energy seems like it would need to introduce more losses than just doing Light to Spren to Kinetic Energy. Not sure what the limits on what attractors and repellers can be set to effect, but it just seems like there should be a convergence on the principles seen in the [checks that I am in the comsere forum] era 2 southern scadrian airships. The motor force comes from magical force being applied to the spiny part, not from running a more general power plant.

I do feel like there is an idea for a kind of "What if a Shardworld was awful because it was like real life?" concept in all of this talk of oil and coal and power. Imagine a world where there are huge wells of energy beneath the rocks and soil, but extracting and using them destroys the ecology of the planet. I suppose this would be something like if Harmony was a pre-existing being whose body was always found within the soil and who would be injured by the taking up of that power recklessly?

[PanLin they/he]

1 minute ago, ParaTulip said:

Have we seen anyone do steam power using flame-spren? Coal and fuel oil are not things that I recall coming up in the Stormlight books, running a steam engine on charcoal sounds like a bad time logistically, and I almost wonder if using attractor and repeller fabriels would not be a better system?

Doing a power conversion from Light to Spren to Water to Steam to Kinetic Energy seems like it would need to introduce more losses than just doing Light to Spren to Kinetic Energy. Not sure what the limits on what attractors and repellers can be set to effect, but it just seems like there should be a convergence on the principles seen in the [checks that I am in the comsere forum] era 2 southern scadrian airships. The motor force comes from magical force being applied to the spiny part, not from running a more general power plant.

I do feel like there is an idea for a kind of "What if a Shardworld was awful because it was like real life?" concept in all of this talk of oil and coal and power. Imagine a world where there are huge wells of energy beneath the rocks and soil, but extracting and using them destroys the ecology of the planet. I suppose this would be something like if Harmony was a pre-existing being whose body was always found within the soil and who would be injured by the taking up of that power recklessly?

Ah that's a good point. I suppose it depends whether the fuel is gathered through mundane or Invested means (eg: mined coal vs soulcast fuel). I wonder how long it'll be before Roshar gets access to Zephyr spores, or even a Fabrial that just converts Warlight directly into matter-based propulsion as their version of a chemical propulsion rocket booster.

I agree with your real-world-sucks parallel! Spoilers for IotE:

Spoiler

The way the Malwish are presented in the future really gives (to me at least) the vibe that they're a highly industrialised civilisation, to have access to such advanced military infrastructure. The steel fields alone (of which they're very proud, and reasonably so) have to be the result of large-scale mining and production operations.

The extra concept of fossil fuel mining weakening a Shard is interesting and very plausible, especially on Scadrial where the planet was made directly by the Shards and is therefore more strongly Invested by Harmony than a lot of other planets. Maybe the same could be said for crem and Cultivation.

Somewhat related and potentially a fun read: there's a worldbuilding project called Cathedris that I've been following for a while that takes the real-world concept of whalefalls (where a slowly decomposing whale carcass takes so long to be used up that it creates its own temporary ecosystem) and applies it to gods. Your example with Harmony reminded me, but this is a much more direct application: the gods in that setting (now mostly mad and dying following a big ol' divine war) have physical bodies made of extremely valuable materials that people have learned to mine and build their entire industrial infrastructure from.

I do that same check to make sure I'm in the Cosmere forum all the time 

 

[Nitpicking]

Why not just grab mandras to pull it?

[PanLin they/he]

1 hour ago, Nitpicking said:

Why not just grab mandras to pull it?

Conjoined fabrials don't work across realms, and mandras can't pull things in the physical realm like they do in the cognitive (unless someone continues Ishar's experiments successfully).

[Through The Living Grub He/Him]

On 4/9/2026 at 5:10 AM, Through the living Wahr said:

I think the biggest Improvement of the Airship would need the discovery/rediscovery of a theoretically possible but not yet seen Surge Fabrial:

Gravitation Fabrial

5 hours ago, Nitpicking said:

Why not just grab mandras to pull it?

I wonder if Mandras could mimic Gravitation when used in a fabrial.

On 4/9/2026 at 10:52 AM, PanLin said:

Anything you want to just wordvomit on and then work out later? We have seen a sort of rudimentary blinking code used on spanreeds a few times—I think the closest to Morse code was in Dawnshard after Huio stumbles on his aluminum discovery, but I don't have that book on me rn to check.

I just read Navani's chapter where she is shown the personal lift fabrial, and here comments on aluminum helped. Basically, a writing board could be set up on the Fourth Bridge but rotated so that the writer's "down" direction is the same as the direction of travel. An aluminum cage could then be used to remove the effect of the ship's motion, and the receiver only gets the writing. This may require both spanreeds be horizontal, but artifabrians in world should be able to solve this problem in a way similar to the personal lift perhaps.