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Medieval flying castle propulsion


How would the design of a habitable underground fortification differ to that of a castle?Medieval low-energy housesThrustless Propulsion and Levitation - Science/Magic theoryCurrency for my medieval gameWould medieval fortifications be effective in a zombie apocalyptic world?How would castles be built in a medieval setting where some humans can fly?Medieval Setting - Castles Per CapitaHow thick a stone castle wall needs to be to withstand a modern tank?Biological Blimps: PropulsionWould a medieval-type castle still arise in an alternate history?













6












$begingroup$


One day, on the faraway world of not-medieval-Europe, someone discovered that a type of stone could be made to float. A decade or two later, there are flying castles, built out of and/or on a foundation of said floating stone.



Floating stone doesn't actually float everywhere. There are large lines (let's call them Ley lines) crisscrossing continents and oceans, where stone floats best on, separated by voids where it doesn't float much, or even at all. Altitude above ground also weaken the effect, so you won't see floating castles more than a few km up at most.



If a floating castle drifts away from a Line, it will (hopefully) gently float down and land - though "gently" at the scale of a castle can still be potentially fatal to anything both in or under the castle.



What propulsion would be used on a floating castle with medieval technology?



Standard airship techniques may not work, as flying castles are so incredibly denser and more massive. Ideally, it would allow for a fair bit of control, to avoid getting pushed out of a Line or into a mountain.



Available tech can be from late Roman to mid-late medieval era. There is no magic apart from floating rock, and it doesn't really scale down.



On the other hand, there have been a few decades with incentives to solve new problems, so new tech can be used if it could have reasonably been invented in those conditions. Likewise, flying castles themselves can help in engineering projects, for example to (slowly) move very large charges up.



The following numbers and assumptions are given as a baseline, but can be changed if it makes things more interesting:




  • The two main things moving a drifting floating castle are wind and natural currents from the Ley line. Generally, the Ley current is weaker though not negligible, and constant on one place. A castle can also very slowly gain and loose altitude. Assuming no ballast drop, a castle can accelerate at about 5 cm/s², with a max ascending speed of 2m/s, in good conditions (descending speed is limited only by lithobraking).


  • The largest flying foundations are roughly 30m radius circles, with 20m-thick foundation. The smallest ones are 8m radius and 6m-thick foundation. The foundation itself is at least 9/10 filled in stone, but there are often small chambres and tunnels for access below. There can be light structures hanging from under the foundation, though most of the mass must be over it.


  • Floating stone has a density of about 2.5 g/cm³. So the biggest castles have a foundation of about 150,000 tons, and the smallest of 3,000 tons. (If other properties are needed, we can use granite as placeholder)


  • Total non-floating-stone carrying capacity of a castle is about 1/3 of the stone mass, for the best-built (and most expensive) models - so 1,000 to 50,000 tons.


  • To save on capacity, walls can be partially built with floating stone, up to about 1/3 of the mass of the foundation. Those walls must be at least 1m thick, but don't count on carrying mass and can be used as support for other structures.


  • Flying castles typically have a smaller slab inside, in a long vertical shaft, capable of independent vertical movement. It is usable only when there is little to no horizontal acceleration, and with a max vertical speed of 10 cm/s. It can be used to raise about 1/30 of the mass of the foundation (so 100 to 5,000 tons). Some people are experimenting with cisterns at both ends, using hydraulic power from the upper cistern, then raising spent water from the lower to the upper one. Not sure how well this scheme would work - this would be the subject of another question, but consider that there is some power available from this, if it can help.











share|improve this question











$endgroup$








  • 5




    $begingroup$
    It seems to me that there's one more important detail we would need to attempt a coherent answer: what prevents a floating castle from "sliding" off the leyline it's riding? If the repulsive effect is weaker on one side of the castle than the other, wouldn't gravity just pull one side down, and the whole thing would start to slide sideways? (I guess, in my head, I'm modelling the repulsive force based on magnetism. It's a finicky thing to try to keep a magnet balanced "on top" of a magnetic field.) So, would you be able to describe the physics of the repulsive force, a bit?
    $endgroup$
    – Qami
    8 hours ago










  • $begingroup$
    @Qami Let's assume it works like an airship whose center of buoyancy is much higher than its center of mass. The CoM is in the foundation slab, but the CoB is at least one radius higher, possibly more. So it is inherently stable, like the scale of a balance. Local variations of the Ley force are generally too small to unbalance the castle - though there may be particularly sharp discontinuities that cannot be averaged out and have to be avoided at all costs...
    $endgroup$
    – Eth
    3 hours ago










  • $begingroup$
    definitely pull with ropes, as Starfish points out.
    $endgroup$
    – Fattie
    36 mins ago










  • $begingroup$
    If a flying castle is intentionally or accidentally moved into a "void" where stone doesn't float, is it effectively stranded there permanently as it's now just regular stone instead of floating stone?
    $endgroup$
    – Nathan Griffiths
    29 mins ago
















6












$begingroup$


One day, on the faraway world of not-medieval-Europe, someone discovered that a type of stone could be made to float. A decade or two later, there are flying castles, built out of and/or on a foundation of said floating stone.



Floating stone doesn't actually float everywhere. There are large lines (let's call them Ley lines) crisscrossing continents and oceans, where stone floats best on, separated by voids where it doesn't float much, or even at all. Altitude above ground also weaken the effect, so you won't see floating castles more than a few km up at most.



If a floating castle drifts away from a Line, it will (hopefully) gently float down and land - though "gently" at the scale of a castle can still be potentially fatal to anything both in or under the castle.



What propulsion would be used on a floating castle with medieval technology?



Standard airship techniques may not work, as flying castles are so incredibly denser and more massive. Ideally, it would allow for a fair bit of control, to avoid getting pushed out of a Line or into a mountain.



Available tech can be from late Roman to mid-late medieval era. There is no magic apart from floating rock, and it doesn't really scale down.



On the other hand, there have been a few decades with incentives to solve new problems, so new tech can be used if it could have reasonably been invented in those conditions. Likewise, flying castles themselves can help in engineering projects, for example to (slowly) move very large charges up.



The following numbers and assumptions are given as a baseline, but can be changed if it makes things more interesting:




  • The two main things moving a drifting floating castle are wind and natural currents from the Ley line. Generally, the Ley current is weaker though not negligible, and constant on one place. A castle can also very slowly gain and loose altitude. Assuming no ballast drop, a castle can accelerate at about 5 cm/s², with a max ascending speed of 2m/s, in good conditions (descending speed is limited only by lithobraking).


  • The largest flying foundations are roughly 30m radius circles, with 20m-thick foundation. The smallest ones are 8m radius and 6m-thick foundation. The foundation itself is at least 9/10 filled in stone, but there are often small chambres and tunnels for access below. There can be light structures hanging from under the foundation, though most of the mass must be over it.


  • Floating stone has a density of about 2.5 g/cm³. So the biggest castles have a foundation of about 150,000 tons, and the smallest of 3,000 tons. (If other properties are needed, we can use granite as placeholder)


  • Total non-floating-stone carrying capacity of a castle is about 1/3 of the stone mass, for the best-built (and most expensive) models - so 1,000 to 50,000 tons.


  • To save on capacity, walls can be partially built with floating stone, up to about 1/3 of the mass of the foundation. Those walls must be at least 1m thick, but don't count on carrying mass and can be used as support for other structures.


  • Flying castles typically have a smaller slab inside, in a long vertical shaft, capable of independent vertical movement. It is usable only when there is little to no horizontal acceleration, and with a max vertical speed of 10 cm/s. It can be used to raise about 1/30 of the mass of the foundation (so 100 to 5,000 tons). Some people are experimenting with cisterns at both ends, using hydraulic power from the upper cistern, then raising spent water from the lower to the upper one. Not sure how well this scheme would work - this would be the subject of another question, but consider that there is some power available from this, if it can help.











share|improve this question











$endgroup$








  • 5




    $begingroup$
    It seems to me that there's one more important detail we would need to attempt a coherent answer: what prevents a floating castle from "sliding" off the leyline it's riding? If the repulsive effect is weaker on one side of the castle than the other, wouldn't gravity just pull one side down, and the whole thing would start to slide sideways? (I guess, in my head, I'm modelling the repulsive force based on magnetism. It's a finicky thing to try to keep a magnet balanced "on top" of a magnetic field.) So, would you be able to describe the physics of the repulsive force, a bit?
    $endgroup$
    – Qami
    8 hours ago










  • $begingroup$
    @Qami Let's assume it works like an airship whose center of buoyancy is much higher than its center of mass. The CoM is in the foundation slab, but the CoB is at least one radius higher, possibly more. So it is inherently stable, like the scale of a balance. Local variations of the Ley force are generally too small to unbalance the castle - though there may be particularly sharp discontinuities that cannot be averaged out and have to be avoided at all costs...
    $endgroup$
    – Eth
    3 hours ago










  • $begingroup$
    definitely pull with ropes, as Starfish points out.
    $endgroup$
    – Fattie
    36 mins ago










  • $begingroup$
    If a flying castle is intentionally or accidentally moved into a "void" where stone doesn't float, is it effectively stranded there permanently as it's now just regular stone instead of floating stone?
    $endgroup$
    – Nathan Griffiths
    29 mins ago














6












6








6


1



$begingroup$


One day, on the faraway world of not-medieval-Europe, someone discovered that a type of stone could be made to float. A decade or two later, there are flying castles, built out of and/or on a foundation of said floating stone.



Floating stone doesn't actually float everywhere. There are large lines (let's call them Ley lines) crisscrossing continents and oceans, where stone floats best on, separated by voids where it doesn't float much, or even at all. Altitude above ground also weaken the effect, so you won't see floating castles more than a few km up at most.



If a floating castle drifts away from a Line, it will (hopefully) gently float down and land - though "gently" at the scale of a castle can still be potentially fatal to anything both in or under the castle.



What propulsion would be used on a floating castle with medieval technology?



Standard airship techniques may not work, as flying castles are so incredibly denser and more massive. Ideally, it would allow for a fair bit of control, to avoid getting pushed out of a Line or into a mountain.



Available tech can be from late Roman to mid-late medieval era. There is no magic apart from floating rock, and it doesn't really scale down.



On the other hand, there have been a few decades with incentives to solve new problems, so new tech can be used if it could have reasonably been invented in those conditions. Likewise, flying castles themselves can help in engineering projects, for example to (slowly) move very large charges up.



The following numbers and assumptions are given as a baseline, but can be changed if it makes things more interesting:




  • The two main things moving a drifting floating castle are wind and natural currents from the Ley line. Generally, the Ley current is weaker though not negligible, and constant on one place. A castle can also very slowly gain and loose altitude. Assuming no ballast drop, a castle can accelerate at about 5 cm/s², with a max ascending speed of 2m/s, in good conditions (descending speed is limited only by lithobraking).


  • The largest flying foundations are roughly 30m radius circles, with 20m-thick foundation. The smallest ones are 8m radius and 6m-thick foundation. The foundation itself is at least 9/10 filled in stone, but there are often small chambres and tunnels for access below. There can be light structures hanging from under the foundation, though most of the mass must be over it.


  • Floating stone has a density of about 2.5 g/cm³. So the biggest castles have a foundation of about 150,000 tons, and the smallest of 3,000 tons. (If other properties are needed, we can use granite as placeholder)


  • Total non-floating-stone carrying capacity of a castle is about 1/3 of the stone mass, for the best-built (and most expensive) models - so 1,000 to 50,000 tons.


  • To save on capacity, walls can be partially built with floating stone, up to about 1/3 of the mass of the foundation. Those walls must be at least 1m thick, but don't count on carrying mass and can be used as support for other structures.


  • Flying castles typically have a smaller slab inside, in a long vertical shaft, capable of independent vertical movement. It is usable only when there is little to no horizontal acceleration, and with a max vertical speed of 10 cm/s. It can be used to raise about 1/30 of the mass of the foundation (so 100 to 5,000 tons). Some people are experimenting with cisterns at both ends, using hydraulic power from the upper cistern, then raising spent water from the lower to the upper one. Not sure how well this scheme would work - this would be the subject of another question, but consider that there is some power available from this, if it can help.











share|improve this question











$endgroup$




One day, on the faraway world of not-medieval-Europe, someone discovered that a type of stone could be made to float. A decade or two later, there are flying castles, built out of and/or on a foundation of said floating stone.



Floating stone doesn't actually float everywhere. There are large lines (let's call them Ley lines) crisscrossing continents and oceans, where stone floats best on, separated by voids where it doesn't float much, or even at all. Altitude above ground also weaken the effect, so you won't see floating castles more than a few km up at most.



If a floating castle drifts away from a Line, it will (hopefully) gently float down and land - though "gently" at the scale of a castle can still be potentially fatal to anything both in or under the castle.



What propulsion would be used on a floating castle with medieval technology?



Standard airship techniques may not work, as flying castles are so incredibly denser and more massive. Ideally, it would allow for a fair bit of control, to avoid getting pushed out of a Line or into a mountain.



Available tech can be from late Roman to mid-late medieval era. There is no magic apart from floating rock, and it doesn't really scale down.



On the other hand, there have been a few decades with incentives to solve new problems, so new tech can be used if it could have reasonably been invented in those conditions. Likewise, flying castles themselves can help in engineering projects, for example to (slowly) move very large charges up.



The following numbers and assumptions are given as a baseline, but can be changed if it makes things more interesting:




  • The two main things moving a drifting floating castle are wind and natural currents from the Ley line. Generally, the Ley current is weaker though not negligible, and constant on one place. A castle can also very slowly gain and loose altitude. Assuming no ballast drop, a castle can accelerate at about 5 cm/s², with a max ascending speed of 2m/s, in good conditions (descending speed is limited only by lithobraking).


  • The largest flying foundations are roughly 30m radius circles, with 20m-thick foundation. The smallest ones are 8m radius and 6m-thick foundation. The foundation itself is at least 9/10 filled in stone, but there are often small chambres and tunnels for access below. There can be light structures hanging from under the foundation, though most of the mass must be over it.


  • Floating stone has a density of about 2.5 g/cm³. So the biggest castles have a foundation of about 150,000 tons, and the smallest of 3,000 tons. (If other properties are needed, we can use granite as placeholder)


  • Total non-floating-stone carrying capacity of a castle is about 1/3 of the stone mass, for the best-built (and most expensive) models - so 1,000 to 50,000 tons.


  • To save on capacity, walls can be partially built with floating stone, up to about 1/3 of the mass of the foundation. Those walls must be at least 1m thick, but don't count on carrying mass and can be used as support for other structures.


  • Flying castles typically have a smaller slab inside, in a long vertical shaft, capable of independent vertical movement. It is usable only when there is little to no horizontal acceleration, and with a max vertical speed of 10 cm/s. It can be used to raise about 1/30 of the mass of the foundation (so 100 to 5,000 tons). Some people are experimenting with cisterns at both ends, using hydraulic power from the upper cistern, then raising spent water from the lower to the upper one. Not sure how well this scheme would work - this would be the subject of another question, but consider that there is some power available from this, if it can help.








science-based technology medieval airships






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 7 hours ago









Glorfindel

4611716




4611716










asked 8 hours ago









EthEth

3,2181823




3,2181823








  • 5




    $begingroup$
    It seems to me that there's one more important detail we would need to attempt a coherent answer: what prevents a floating castle from "sliding" off the leyline it's riding? If the repulsive effect is weaker on one side of the castle than the other, wouldn't gravity just pull one side down, and the whole thing would start to slide sideways? (I guess, in my head, I'm modelling the repulsive force based on magnetism. It's a finicky thing to try to keep a magnet balanced "on top" of a magnetic field.) So, would you be able to describe the physics of the repulsive force, a bit?
    $endgroup$
    – Qami
    8 hours ago










  • $begingroup$
    @Qami Let's assume it works like an airship whose center of buoyancy is much higher than its center of mass. The CoM is in the foundation slab, but the CoB is at least one radius higher, possibly more. So it is inherently stable, like the scale of a balance. Local variations of the Ley force are generally too small to unbalance the castle - though there may be particularly sharp discontinuities that cannot be averaged out and have to be avoided at all costs...
    $endgroup$
    – Eth
    3 hours ago










  • $begingroup$
    definitely pull with ropes, as Starfish points out.
    $endgroup$
    – Fattie
    36 mins ago










  • $begingroup$
    If a flying castle is intentionally or accidentally moved into a "void" where stone doesn't float, is it effectively stranded there permanently as it's now just regular stone instead of floating stone?
    $endgroup$
    – Nathan Griffiths
    29 mins ago














  • 5




    $begingroup$
    It seems to me that there's one more important detail we would need to attempt a coherent answer: what prevents a floating castle from "sliding" off the leyline it's riding? If the repulsive effect is weaker on one side of the castle than the other, wouldn't gravity just pull one side down, and the whole thing would start to slide sideways? (I guess, in my head, I'm modelling the repulsive force based on magnetism. It's a finicky thing to try to keep a magnet balanced "on top" of a magnetic field.) So, would you be able to describe the physics of the repulsive force, a bit?
    $endgroup$
    – Qami
    8 hours ago










  • $begingroup$
    @Qami Let's assume it works like an airship whose center of buoyancy is much higher than its center of mass. The CoM is in the foundation slab, but the CoB is at least one radius higher, possibly more. So it is inherently stable, like the scale of a balance. Local variations of the Ley force are generally too small to unbalance the castle - though there may be particularly sharp discontinuities that cannot be averaged out and have to be avoided at all costs...
    $endgroup$
    – Eth
    3 hours ago










  • $begingroup$
    definitely pull with ropes, as Starfish points out.
    $endgroup$
    – Fattie
    36 mins ago










  • $begingroup$
    If a flying castle is intentionally or accidentally moved into a "void" where stone doesn't float, is it effectively stranded there permanently as it's now just regular stone instead of floating stone?
    $endgroup$
    – Nathan Griffiths
    29 mins ago








5




5




$begingroup$
It seems to me that there's one more important detail we would need to attempt a coherent answer: what prevents a floating castle from "sliding" off the leyline it's riding? If the repulsive effect is weaker on one side of the castle than the other, wouldn't gravity just pull one side down, and the whole thing would start to slide sideways? (I guess, in my head, I'm modelling the repulsive force based on magnetism. It's a finicky thing to try to keep a magnet balanced "on top" of a magnetic field.) So, would you be able to describe the physics of the repulsive force, a bit?
$endgroup$
– Qami
8 hours ago




$begingroup$
It seems to me that there's one more important detail we would need to attempt a coherent answer: what prevents a floating castle from "sliding" off the leyline it's riding? If the repulsive effect is weaker on one side of the castle than the other, wouldn't gravity just pull one side down, and the whole thing would start to slide sideways? (I guess, in my head, I'm modelling the repulsive force based on magnetism. It's a finicky thing to try to keep a magnet balanced "on top" of a magnetic field.) So, would you be able to describe the physics of the repulsive force, a bit?
$endgroup$
– Qami
8 hours ago












$begingroup$
@Qami Let's assume it works like an airship whose center of buoyancy is much higher than its center of mass. The CoM is in the foundation slab, but the CoB is at least one radius higher, possibly more. So it is inherently stable, like the scale of a balance. Local variations of the Ley force are generally too small to unbalance the castle - though there may be particularly sharp discontinuities that cannot be averaged out and have to be avoided at all costs...
$endgroup$
– Eth
3 hours ago




$begingroup$
@Qami Let's assume it works like an airship whose center of buoyancy is much higher than its center of mass. The CoM is in the foundation slab, but the CoB is at least one radius higher, possibly more. So it is inherently stable, like the scale of a balance. Local variations of the Ley force are generally too small to unbalance the castle - though there may be particularly sharp discontinuities that cannot be averaged out and have to be avoided at all costs...
$endgroup$
– Eth
3 hours ago












$begingroup$
definitely pull with ropes, as Starfish points out.
$endgroup$
– Fattie
36 mins ago




$begingroup$
definitely pull with ropes, as Starfish points out.
$endgroup$
– Fattie
36 mins ago












$begingroup$
If a flying castle is intentionally or accidentally moved into a "void" where stone doesn't float, is it effectively stranded there permanently as it's now just regular stone instead of floating stone?
$endgroup$
– Nathan Griffiths
29 mins ago




$begingroup$
If a flying castle is intentionally or accidentally moved into a "void" where stone doesn't float, is it effectively stranded there permanently as it's now just regular stone instead of floating stone?
$endgroup$
– Nathan Griffiths
29 mins ago










5 Answers
5






active

oldest

votes


















5












$begingroup$

Brute force. Lots of inertia in a castle, so you'll have problems making an engine sufficiently powerful to drive a propellor to move it along, even if you had substantially more advantaged technology than was generally available in the medieval period.



Therefore, brute force.



One means of brute force is to just get a lot of slaves on the end of ropes. This might be a good reason to get back to the good old loot'n'enslave warfare that was so popular back in the axial age. A slightly less ethically challenged option would be to use lots of draft animals... oxen would probably do, because you don't want to get up too much speed with a castle.



Another possibility is to use anchors and capstans, and use mechanical advantage to haul your castle up towards an anchor, and then (slightly less) brute force to move your anchor points in the direction you wish to go. You might have to use this method to make headway against very strong winds, and you'll definitely want to be anchoring your castle in place when you're not moving it around.



There's a minor additional benefit here in that you could perhaps fire a lightweight anchor via a siege weapon, and therefore be able to haul yourself along without actually putting troops or animals on the ground. This would be useful for navigating hostile or otherwise impassible terrain such as mountains, swamps or shallow lakes and rivers.






share|improve this answer









$endgroup$





















    4












    $begingroup$

    You should work on the physics behind the floating rocks. What is the principle that makes them float?



    We know that the force of the stones is parallel (but opposite in verse) to the gravity, so it alway points toward the sky.

    This means that the rocks can only make the castle stay afloat. In order to move the castle, you need a force that can be addressed, with a parallel component with respect to the surface.



    You said that, far from the Line, the floating power of the rocks gradually vanishes, as well as it is weaker the higher you are from the surface, so we can make some assumptions.
    Everything sounds as if there is a repulsive force from the ground (1), as well as a material that can dampen the force toward the sky that is generated by such stones (which should be plentiful far from the Line).

    Now, let's say that I can shield my floating stones:



    enter image description here
    The mortals tremble in the presence of my superior Paint skills!



    An unshielded stone, receives repulsive force from all directions, so that all the components parallel to surface cancel themselves. A shielded one, receive only the forces from one direction, so that it has a smaller component toward the sky, but also a component parallel to the surface, pointing in the opposite verse with respect to the opening in the shielding.



    So, a castle could have some big unshielded stones, mainly used to keep everything afloat, and one or more partially shielded stones, mounted on joints that can be orientated, to propel and steer the castle itself.



    (1) But let's be careful: the repulsive force from something that can be approximated as an infinite plane would be the same at every distance from the plane itself (in other words, it wouldn't fade with height). I suppose that the Line is thin enough that the ground under the castle can't be considered an infinite, repulsive, plane.






    share|improve this answer









    $endgroup$









    • 1




      $begingroup$
      Careful use of massive keels may also be required to avoid embarassing incidents like the famous Fort I've Fallen And I Can't Get Up.
      $endgroup$
      – Starfish Prime
      6 hours ago










    • $begingroup$
      @Starfish Prime Well, maybe the people in the castle would be prepared for such eventualities... for instance, in the living room, they would keep a set of forniture bolted to the floor and another one bolted to the ceiling :D
      $endgroup$
      – McTroopers
      4 hours ago












    • $begingroup$
      Beating the RP FLIP to the sideways-bathroom design by centuries ;-)
      $endgroup$
      – Starfish Prime
      4 hours ago










    • $begingroup$
      @Starfish Prime What's that feeling, when you think you've just said a really really absurd joke, and then discover that it is something that really exists? :D
      $endgroup$
      – McTroopers
      4 hours ago



















    2












    $begingroup$

    Tracks.



    I wondered for how long people had been using rail-type tracks to move cargo overland. A long time: I found the Diolkos, used by the ancient Greeks to move ships overland.



    https://en.wikipedia.org/wiki/Diolkos




    The Diolkos was a trackway paved with hard limestone[26] with parallel
    grooves running about 1.60 metres (63 in) apart.[31] The roadway was
    3.4 to 6 metres (11 to 20 ft) wide.[26] Since ancient sources tell little about how the ships were hauled across,[24] the mode of ship
    transport has largely to be reconstructed from the archaeological
    evidence. The tracks indicate that transport on the Diolkos was done
    with some sort of wheeled vehicle.




    Your ley lines would have parallel tracks along them, probably of stone. Stays down within the tracks would prevent upward motion of the castle and having two would prevent lateral movement out of the influence of the ley lines supporting power.



    The castle would be moved by sliding the stays along the tracks. A team of oxen could do this, in the same manner an ox team might pull a barge. Depending on the distance between the two stays you might need 2 teams working together.



    You could do away with the stays and rails and just use the ox teams but you would need to have a cart heavy enough to oppose the lifting power of the castle which is more work to move.






    share|improve this answer









    $endgroup$





















      1












      $begingroup$

      Ley-Line Canals



      An image of the Segovia Aqueduct
      https://commons.wikimedia.org/wiki/File:Segovia_Aqueduct.JPG



      Your castles may float along dedicated canals which are specifically built to allow for floating castles to navigate them. The Romans famously built aqueducts for transporting water, if you built something similar, it would allow for you to easily transport your castles around.



      The canals would be constructed along the paths of the ley-lines, essentially acting as guides to prevent the castle from drifting away from the ley-line. This also means you will not accidentally drift into a “dead zone” where the stones do not float at all, which would cause a castle to crash.



      Sails



      Canals alone though wont cause you to move forward. Instead, as you are now floating along fixed lines, like a railroad track, you can now safely use sails to push you forwards. Before, without he canal, you risked being pushed out of the ley-line. Now though, as you are more firmly fixed into the line, there is significantly less of a chance for you to be pushed out, most momentum from the wind should push you forwards (assuming you angle your sails correctly and the wind is not blowing in the complete opposite direction you want to go).



      Wheels



      Alternatively, you might opt to use wheels to move your castles. Wheels would run along grooves in the canal and could be powered through a number of ways, such as by man power, using beasts of burden or even with falling water like a watermill. Don’t expect the castle to move particularly quickly though.



      One problem with the concept of using canals though is they would take a very long time to build everywhere. Perhaps you only have canals on major routs, such as between cities (much like how highways only run between large cities and smaller towns build up along those routs). You could also take from the idea of shipping lanes where canals are only built on well-established and often used routs.



      Magnetism



      Essentially, your castles could work like levitating trains. Your stones would work like magnets, repelling away from the ley-line which causes them to float. If you can invert that signal, causing them to be pulled towards the ley-line rather than being pushed away, you could propel yourself through the power of magnetism (not really magnets per say but they function similarly enough).



      The way magnetic trains work is by turning on and off magnets in a certain order, causing the train to be pulled forward. Your stones could be turned on and off, when they are on, they float on the ley-line, when they are off, they fall.



      So how can we turn this into forward movement? Well if we start with all of the stones being turned on, the castle will be floating and relatively stationary (barring the flow of the ley-line and the wind pushing it). What we do next is turn off the stones at the front of the castle, only for a fraction of a second, which will cause the castle to tilt slightly forwards. The force of gravity will start pulling the castle downwards on that side, pulling it forward. To prevent us from crashing, we turn the stone back on, floating us back up, only now we are slightly further forward. If we keep repeating this process rapidly, we will soon start to build up significant speed, despite the castles high mass.



      This concept is very similar to that of the rail gun which uses electromagnetic force to move a metallic object at high speed. Contrary to its name, it is not just intended for weaponry, NASA proposed to use a rail gun to accelerate small aircraft or spacecraft into orbit..






      share|improve this answer









      $endgroup$





















        0












        $begingroup$

        You should be able to sail the castle, the issue would be sail material, you'd be using bamboo, timber and metal rather than cloth because the structures are going to be too large for traditional fabric. Controlling sails that large will be challenging but not impossible, I'd think that capstan and treadwheel driven winches would be sufficient.






        share|improve this answer











        $endgroup$









        • 1




          $begingroup$
          Sailing only works because the hull of the boat is in the sea and can provide lateral resistance. Similarly, landsailing works because the wheels provide lateral resistance. Free-floating objects with sails will simply blow downwind. If the wind is blowing along your Line then you're in luck, otherwise you simply cannot use sails at all.
          $endgroup$
          – Starfish Prime
          7 hours ago










        • $begingroup$
          @StarfishPrime Of course you can, you can play the pressure on different sets of sails off each other to get differential movement, also the ley line current will act as the differential current against the winds that you need to get movement out of sails in any vessel.
          $endgroup$
          – Ash
          7 hours ago










        • $begingroup$
          You will, at best, be able to slightly change your downwind vector. The OP explicitly states that castles are able to drift from their Lines, and as such you clearly cannot rely on them to provide a stabilising force of any useful magnitude.
          $endgroup$
          – Starfish Prime
          7 hours ago










        • $begingroup$
          Starfish Prime is correct about this. This is the reason sails have never been used on zeppelins/blimps (outside of fanciful airships from video games and animes etc.)
          $endgroup$
          – Qami
          6 hours ago












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        5 Answers
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        5 Answers
        5






        active

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        5












        $begingroup$

        Brute force. Lots of inertia in a castle, so you'll have problems making an engine sufficiently powerful to drive a propellor to move it along, even if you had substantially more advantaged technology than was generally available in the medieval period.



        Therefore, brute force.



        One means of brute force is to just get a lot of slaves on the end of ropes. This might be a good reason to get back to the good old loot'n'enslave warfare that was so popular back in the axial age. A slightly less ethically challenged option would be to use lots of draft animals... oxen would probably do, because you don't want to get up too much speed with a castle.



        Another possibility is to use anchors and capstans, and use mechanical advantage to haul your castle up towards an anchor, and then (slightly less) brute force to move your anchor points in the direction you wish to go. You might have to use this method to make headway against very strong winds, and you'll definitely want to be anchoring your castle in place when you're not moving it around.



        There's a minor additional benefit here in that you could perhaps fire a lightweight anchor via a siege weapon, and therefore be able to haul yourself along without actually putting troops or animals on the ground. This would be useful for navigating hostile or otherwise impassible terrain such as mountains, swamps or shallow lakes and rivers.






        share|improve this answer









        $endgroup$


















          5












          $begingroup$

          Brute force. Lots of inertia in a castle, so you'll have problems making an engine sufficiently powerful to drive a propellor to move it along, even if you had substantially more advantaged technology than was generally available in the medieval period.



          Therefore, brute force.



          One means of brute force is to just get a lot of slaves on the end of ropes. This might be a good reason to get back to the good old loot'n'enslave warfare that was so popular back in the axial age. A slightly less ethically challenged option would be to use lots of draft animals... oxen would probably do, because you don't want to get up too much speed with a castle.



          Another possibility is to use anchors and capstans, and use mechanical advantage to haul your castle up towards an anchor, and then (slightly less) brute force to move your anchor points in the direction you wish to go. You might have to use this method to make headway against very strong winds, and you'll definitely want to be anchoring your castle in place when you're not moving it around.



          There's a minor additional benefit here in that you could perhaps fire a lightweight anchor via a siege weapon, and therefore be able to haul yourself along without actually putting troops or animals on the ground. This would be useful for navigating hostile or otherwise impassible terrain such as mountains, swamps or shallow lakes and rivers.






          share|improve this answer









          $endgroup$
















            5












            5








            5





            $begingroup$

            Brute force. Lots of inertia in a castle, so you'll have problems making an engine sufficiently powerful to drive a propellor to move it along, even if you had substantially more advantaged technology than was generally available in the medieval period.



            Therefore, brute force.



            One means of brute force is to just get a lot of slaves on the end of ropes. This might be a good reason to get back to the good old loot'n'enslave warfare that was so popular back in the axial age. A slightly less ethically challenged option would be to use lots of draft animals... oxen would probably do, because you don't want to get up too much speed with a castle.



            Another possibility is to use anchors and capstans, and use mechanical advantage to haul your castle up towards an anchor, and then (slightly less) brute force to move your anchor points in the direction you wish to go. You might have to use this method to make headway against very strong winds, and you'll definitely want to be anchoring your castle in place when you're not moving it around.



            There's a minor additional benefit here in that you could perhaps fire a lightweight anchor via a siege weapon, and therefore be able to haul yourself along without actually putting troops or animals on the ground. This would be useful for navigating hostile or otherwise impassible terrain such as mountains, swamps or shallow lakes and rivers.






            share|improve this answer









            $endgroup$



            Brute force. Lots of inertia in a castle, so you'll have problems making an engine sufficiently powerful to drive a propellor to move it along, even if you had substantially more advantaged technology than was generally available in the medieval period.



            Therefore, brute force.



            One means of brute force is to just get a lot of slaves on the end of ropes. This might be a good reason to get back to the good old loot'n'enslave warfare that was so popular back in the axial age. A slightly less ethically challenged option would be to use lots of draft animals... oxen would probably do, because you don't want to get up too much speed with a castle.



            Another possibility is to use anchors and capstans, and use mechanical advantage to haul your castle up towards an anchor, and then (slightly less) brute force to move your anchor points in the direction you wish to go. You might have to use this method to make headway against very strong winds, and you'll definitely want to be anchoring your castle in place when you're not moving it around.



            There's a minor additional benefit here in that you could perhaps fire a lightweight anchor via a siege weapon, and therefore be able to haul yourself along without actually putting troops or animals on the ground. This would be useful for navigating hostile or otherwise impassible terrain such as mountains, swamps or shallow lakes and rivers.







            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered 8 hours ago









            Starfish PrimeStarfish Prime

            4,877934




            4,877934























                4












                $begingroup$

                You should work on the physics behind the floating rocks. What is the principle that makes them float?



                We know that the force of the stones is parallel (but opposite in verse) to the gravity, so it alway points toward the sky.

                This means that the rocks can only make the castle stay afloat. In order to move the castle, you need a force that can be addressed, with a parallel component with respect to the surface.



                You said that, far from the Line, the floating power of the rocks gradually vanishes, as well as it is weaker the higher you are from the surface, so we can make some assumptions.
                Everything sounds as if there is a repulsive force from the ground (1), as well as a material that can dampen the force toward the sky that is generated by such stones (which should be plentiful far from the Line).

                Now, let's say that I can shield my floating stones:



                enter image description here
                The mortals tremble in the presence of my superior Paint skills!



                An unshielded stone, receives repulsive force from all directions, so that all the components parallel to surface cancel themselves. A shielded one, receive only the forces from one direction, so that it has a smaller component toward the sky, but also a component parallel to the surface, pointing in the opposite verse with respect to the opening in the shielding.



                So, a castle could have some big unshielded stones, mainly used to keep everything afloat, and one or more partially shielded stones, mounted on joints that can be orientated, to propel and steer the castle itself.



                (1) But let's be careful: the repulsive force from something that can be approximated as an infinite plane would be the same at every distance from the plane itself (in other words, it wouldn't fade with height). I suppose that the Line is thin enough that the ground under the castle can't be considered an infinite, repulsive, plane.






                share|improve this answer









                $endgroup$









                • 1




                  $begingroup$
                  Careful use of massive keels may also be required to avoid embarassing incidents like the famous Fort I've Fallen And I Can't Get Up.
                  $endgroup$
                  – Starfish Prime
                  6 hours ago










                • $begingroup$
                  @Starfish Prime Well, maybe the people in the castle would be prepared for such eventualities... for instance, in the living room, they would keep a set of forniture bolted to the floor and another one bolted to the ceiling :D
                  $endgroup$
                  – McTroopers
                  4 hours ago












                • $begingroup$
                  Beating the RP FLIP to the sideways-bathroom design by centuries ;-)
                  $endgroup$
                  – Starfish Prime
                  4 hours ago










                • $begingroup$
                  @Starfish Prime What's that feeling, when you think you've just said a really really absurd joke, and then discover that it is something that really exists? :D
                  $endgroup$
                  – McTroopers
                  4 hours ago
















                4












                $begingroup$

                You should work on the physics behind the floating rocks. What is the principle that makes them float?



                We know that the force of the stones is parallel (but opposite in verse) to the gravity, so it alway points toward the sky.

                This means that the rocks can only make the castle stay afloat. In order to move the castle, you need a force that can be addressed, with a parallel component with respect to the surface.



                You said that, far from the Line, the floating power of the rocks gradually vanishes, as well as it is weaker the higher you are from the surface, so we can make some assumptions.
                Everything sounds as if there is a repulsive force from the ground (1), as well as a material that can dampen the force toward the sky that is generated by such stones (which should be plentiful far from the Line).

                Now, let's say that I can shield my floating stones:



                enter image description here
                The mortals tremble in the presence of my superior Paint skills!



                An unshielded stone, receives repulsive force from all directions, so that all the components parallel to surface cancel themselves. A shielded one, receive only the forces from one direction, so that it has a smaller component toward the sky, but also a component parallel to the surface, pointing in the opposite verse with respect to the opening in the shielding.



                So, a castle could have some big unshielded stones, mainly used to keep everything afloat, and one or more partially shielded stones, mounted on joints that can be orientated, to propel and steer the castle itself.



                (1) But let's be careful: the repulsive force from something that can be approximated as an infinite plane would be the same at every distance from the plane itself (in other words, it wouldn't fade with height). I suppose that the Line is thin enough that the ground under the castle can't be considered an infinite, repulsive, plane.






                share|improve this answer









                $endgroup$









                • 1




                  $begingroup$
                  Careful use of massive keels may also be required to avoid embarassing incidents like the famous Fort I've Fallen And I Can't Get Up.
                  $endgroup$
                  – Starfish Prime
                  6 hours ago










                • $begingroup$
                  @Starfish Prime Well, maybe the people in the castle would be prepared for such eventualities... for instance, in the living room, they would keep a set of forniture bolted to the floor and another one bolted to the ceiling :D
                  $endgroup$
                  – McTroopers
                  4 hours ago












                • $begingroup$
                  Beating the RP FLIP to the sideways-bathroom design by centuries ;-)
                  $endgroup$
                  – Starfish Prime
                  4 hours ago










                • $begingroup$
                  @Starfish Prime What's that feeling, when you think you've just said a really really absurd joke, and then discover that it is something that really exists? :D
                  $endgroup$
                  – McTroopers
                  4 hours ago














                4












                4








                4





                $begingroup$

                You should work on the physics behind the floating rocks. What is the principle that makes them float?



                We know that the force of the stones is parallel (but opposite in verse) to the gravity, so it alway points toward the sky.

                This means that the rocks can only make the castle stay afloat. In order to move the castle, you need a force that can be addressed, with a parallel component with respect to the surface.



                You said that, far from the Line, the floating power of the rocks gradually vanishes, as well as it is weaker the higher you are from the surface, so we can make some assumptions.
                Everything sounds as if there is a repulsive force from the ground (1), as well as a material that can dampen the force toward the sky that is generated by such stones (which should be plentiful far from the Line).

                Now, let's say that I can shield my floating stones:



                enter image description here
                The mortals tremble in the presence of my superior Paint skills!



                An unshielded stone, receives repulsive force from all directions, so that all the components parallel to surface cancel themselves. A shielded one, receive only the forces from one direction, so that it has a smaller component toward the sky, but also a component parallel to the surface, pointing in the opposite verse with respect to the opening in the shielding.



                So, a castle could have some big unshielded stones, mainly used to keep everything afloat, and one or more partially shielded stones, mounted on joints that can be orientated, to propel and steer the castle itself.



                (1) But let's be careful: the repulsive force from something that can be approximated as an infinite plane would be the same at every distance from the plane itself (in other words, it wouldn't fade with height). I suppose that the Line is thin enough that the ground under the castle can't be considered an infinite, repulsive, plane.






                share|improve this answer









                $endgroup$



                You should work on the physics behind the floating rocks. What is the principle that makes them float?



                We know that the force of the stones is parallel (but opposite in verse) to the gravity, so it alway points toward the sky.

                This means that the rocks can only make the castle stay afloat. In order to move the castle, you need a force that can be addressed, with a parallel component with respect to the surface.



                You said that, far from the Line, the floating power of the rocks gradually vanishes, as well as it is weaker the higher you are from the surface, so we can make some assumptions.
                Everything sounds as if there is a repulsive force from the ground (1), as well as a material that can dampen the force toward the sky that is generated by such stones (which should be plentiful far from the Line).

                Now, let's say that I can shield my floating stones:



                enter image description here
                The mortals tremble in the presence of my superior Paint skills!



                An unshielded stone, receives repulsive force from all directions, so that all the components parallel to surface cancel themselves. A shielded one, receive only the forces from one direction, so that it has a smaller component toward the sky, but also a component parallel to the surface, pointing in the opposite verse with respect to the opening in the shielding.



                So, a castle could have some big unshielded stones, mainly used to keep everything afloat, and one or more partially shielded stones, mounted on joints that can be orientated, to propel and steer the castle itself.



                (1) But let's be careful: the repulsive force from something that can be approximated as an infinite plane would be the same at every distance from the plane itself (in other words, it wouldn't fade with height). I suppose that the Line is thin enough that the ground under the castle can't be considered an infinite, repulsive, plane.







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered 6 hours ago









                McTroopersMcTroopers

                2,329110




                2,329110








                • 1




                  $begingroup$
                  Careful use of massive keels may also be required to avoid embarassing incidents like the famous Fort I've Fallen And I Can't Get Up.
                  $endgroup$
                  – Starfish Prime
                  6 hours ago










                • $begingroup$
                  @Starfish Prime Well, maybe the people in the castle would be prepared for such eventualities... for instance, in the living room, they would keep a set of forniture bolted to the floor and another one bolted to the ceiling :D
                  $endgroup$
                  – McTroopers
                  4 hours ago












                • $begingroup$
                  Beating the RP FLIP to the sideways-bathroom design by centuries ;-)
                  $endgroup$
                  – Starfish Prime
                  4 hours ago










                • $begingroup$
                  @Starfish Prime What's that feeling, when you think you've just said a really really absurd joke, and then discover that it is something that really exists? :D
                  $endgroup$
                  – McTroopers
                  4 hours ago














                • 1




                  $begingroup$
                  Careful use of massive keels may also be required to avoid embarassing incidents like the famous Fort I've Fallen And I Can't Get Up.
                  $endgroup$
                  – Starfish Prime
                  6 hours ago










                • $begingroup$
                  @Starfish Prime Well, maybe the people in the castle would be prepared for such eventualities... for instance, in the living room, they would keep a set of forniture bolted to the floor and another one bolted to the ceiling :D
                  $endgroup$
                  – McTroopers
                  4 hours ago












                • $begingroup$
                  Beating the RP FLIP to the sideways-bathroom design by centuries ;-)
                  $endgroup$
                  – Starfish Prime
                  4 hours ago










                • $begingroup$
                  @Starfish Prime What's that feeling, when you think you've just said a really really absurd joke, and then discover that it is something that really exists? :D
                  $endgroup$
                  – McTroopers
                  4 hours ago








                1




                1




                $begingroup$
                Careful use of massive keels may also be required to avoid embarassing incidents like the famous Fort I've Fallen And I Can't Get Up.
                $endgroup$
                – Starfish Prime
                6 hours ago




                $begingroup$
                Careful use of massive keels may also be required to avoid embarassing incidents like the famous Fort I've Fallen And I Can't Get Up.
                $endgroup$
                – Starfish Prime
                6 hours ago












                $begingroup$
                @Starfish Prime Well, maybe the people in the castle would be prepared for such eventualities... for instance, in the living room, they would keep a set of forniture bolted to the floor and another one bolted to the ceiling :D
                $endgroup$
                – McTroopers
                4 hours ago






                $begingroup$
                @Starfish Prime Well, maybe the people in the castle would be prepared for such eventualities... for instance, in the living room, they would keep a set of forniture bolted to the floor and another one bolted to the ceiling :D
                $endgroup$
                – McTroopers
                4 hours ago














                $begingroup$
                Beating the RP FLIP to the sideways-bathroom design by centuries ;-)
                $endgroup$
                – Starfish Prime
                4 hours ago




                $begingroup$
                Beating the RP FLIP to the sideways-bathroom design by centuries ;-)
                $endgroup$
                – Starfish Prime
                4 hours ago












                $begingroup$
                @Starfish Prime What's that feeling, when you think you've just said a really really absurd joke, and then discover that it is something that really exists? :D
                $endgroup$
                – McTroopers
                4 hours ago




                $begingroup$
                @Starfish Prime What's that feeling, when you think you've just said a really really absurd joke, and then discover that it is something that really exists? :D
                $endgroup$
                – McTroopers
                4 hours ago











                2












                $begingroup$

                Tracks.



                I wondered for how long people had been using rail-type tracks to move cargo overland. A long time: I found the Diolkos, used by the ancient Greeks to move ships overland.



                https://en.wikipedia.org/wiki/Diolkos




                The Diolkos was a trackway paved with hard limestone[26] with parallel
                grooves running about 1.60 metres (63 in) apart.[31] The roadway was
                3.4 to 6 metres (11 to 20 ft) wide.[26] Since ancient sources tell little about how the ships were hauled across,[24] the mode of ship
                transport has largely to be reconstructed from the archaeological
                evidence. The tracks indicate that transport on the Diolkos was done
                with some sort of wheeled vehicle.




                Your ley lines would have parallel tracks along them, probably of stone. Stays down within the tracks would prevent upward motion of the castle and having two would prevent lateral movement out of the influence of the ley lines supporting power.



                The castle would be moved by sliding the stays along the tracks. A team of oxen could do this, in the same manner an ox team might pull a barge. Depending on the distance between the two stays you might need 2 teams working together.



                You could do away with the stays and rails and just use the ox teams but you would need to have a cart heavy enough to oppose the lifting power of the castle which is more work to move.






                share|improve this answer









                $endgroup$


















                  2












                  $begingroup$

                  Tracks.



                  I wondered for how long people had been using rail-type tracks to move cargo overland. A long time: I found the Diolkos, used by the ancient Greeks to move ships overland.



                  https://en.wikipedia.org/wiki/Diolkos




                  The Diolkos was a trackway paved with hard limestone[26] with parallel
                  grooves running about 1.60 metres (63 in) apart.[31] The roadway was
                  3.4 to 6 metres (11 to 20 ft) wide.[26] Since ancient sources tell little about how the ships were hauled across,[24] the mode of ship
                  transport has largely to be reconstructed from the archaeological
                  evidence. The tracks indicate that transport on the Diolkos was done
                  with some sort of wheeled vehicle.




                  Your ley lines would have parallel tracks along them, probably of stone. Stays down within the tracks would prevent upward motion of the castle and having two would prevent lateral movement out of the influence of the ley lines supporting power.



                  The castle would be moved by sliding the stays along the tracks. A team of oxen could do this, in the same manner an ox team might pull a barge. Depending on the distance between the two stays you might need 2 teams working together.



                  You could do away with the stays and rails and just use the ox teams but you would need to have a cart heavy enough to oppose the lifting power of the castle which is more work to move.






                  share|improve this answer









                  $endgroup$
















                    2












                    2








                    2





                    $begingroup$

                    Tracks.



                    I wondered for how long people had been using rail-type tracks to move cargo overland. A long time: I found the Diolkos, used by the ancient Greeks to move ships overland.



                    https://en.wikipedia.org/wiki/Diolkos




                    The Diolkos was a trackway paved with hard limestone[26] with parallel
                    grooves running about 1.60 metres (63 in) apart.[31] The roadway was
                    3.4 to 6 metres (11 to 20 ft) wide.[26] Since ancient sources tell little about how the ships were hauled across,[24] the mode of ship
                    transport has largely to be reconstructed from the archaeological
                    evidence. The tracks indicate that transport on the Diolkos was done
                    with some sort of wheeled vehicle.




                    Your ley lines would have parallel tracks along them, probably of stone. Stays down within the tracks would prevent upward motion of the castle and having two would prevent lateral movement out of the influence of the ley lines supporting power.



                    The castle would be moved by sliding the stays along the tracks. A team of oxen could do this, in the same manner an ox team might pull a barge. Depending on the distance between the two stays you might need 2 teams working together.



                    You could do away with the stays and rails and just use the ox teams but you would need to have a cart heavy enough to oppose the lifting power of the castle which is more work to move.






                    share|improve this answer









                    $endgroup$



                    Tracks.



                    I wondered for how long people had been using rail-type tracks to move cargo overland. A long time: I found the Diolkos, used by the ancient Greeks to move ships overland.



                    https://en.wikipedia.org/wiki/Diolkos




                    The Diolkos was a trackway paved with hard limestone[26] with parallel
                    grooves running about 1.60 metres (63 in) apart.[31] The roadway was
                    3.4 to 6 metres (11 to 20 ft) wide.[26] Since ancient sources tell little about how the ships were hauled across,[24] the mode of ship
                    transport has largely to be reconstructed from the archaeological
                    evidence. The tracks indicate that transport on the Diolkos was done
                    with some sort of wheeled vehicle.




                    Your ley lines would have parallel tracks along them, probably of stone. Stays down within the tracks would prevent upward motion of the castle and having two would prevent lateral movement out of the influence of the ley lines supporting power.



                    The castle would be moved by sliding the stays along the tracks. A team of oxen could do this, in the same manner an ox team might pull a barge. Depending on the distance between the two stays you might need 2 teams working together.



                    You could do away with the stays and rails and just use the ox teams but you would need to have a cart heavy enough to oppose the lifting power of the castle which is more work to move.







                    share|improve this answer












                    share|improve this answer



                    share|improve this answer










                    answered 6 hours ago









                    WillkWillk

                    125k29232518




                    125k29232518























                        1












                        $begingroup$

                        Ley-Line Canals



                        An image of the Segovia Aqueduct
                        https://commons.wikimedia.org/wiki/File:Segovia_Aqueduct.JPG



                        Your castles may float along dedicated canals which are specifically built to allow for floating castles to navigate them. The Romans famously built aqueducts for transporting water, if you built something similar, it would allow for you to easily transport your castles around.



                        The canals would be constructed along the paths of the ley-lines, essentially acting as guides to prevent the castle from drifting away from the ley-line. This also means you will not accidentally drift into a “dead zone” where the stones do not float at all, which would cause a castle to crash.



                        Sails



                        Canals alone though wont cause you to move forward. Instead, as you are now floating along fixed lines, like a railroad track, you can now safely use sails to push you forwards. Before, without he canal, you risked being pushed out of the ley-line. Now though, as you are more firmly fixed into the line, there is significantly less of a chance for you to be pushed out, most momentum from the wind should push you forwards (assuming you angle your sails correctly and the wind is not blowing in the complete opposite direction you want to go).



                        Wheels



                        Alternatively, you might opt to use wheels to move your castles. Wheels would run along grooves in the canal and could be powered through a number of ways, such as by man power, using beasts of burden or even with falling water like a watermill. Don’t expect the castle to move particularly quickly though.



                        One problem with the concept of using canals though is they would take a very long time to build everywhere. Perhaps you only have canals on major routs, such as between cities (much like how highways only run between large cities and smaller towns build up along those routs). You could also take from the idea of shipping lanes where canals are only built on well-established and often used routs.



                        Magnetism



                        Essentially, your castles could work like levitating trains. Your stones would work like magnets, repelling away from the ley-line which causes them to float. If you can invert that signal, causing them to be pulled towards the ley-line rather than being pushed away, you could propel yourself through the power of magnetism (not really magnets per say but they function similarly enough).



                        The way magnetic trains work is by turning on and off magnets in a certain order, causing the train to be pulled forward. Your stones could be turned on and off, when they are on, they float on the ley-line, when they are off, they fall.



                        So how can we turn this into forward movement? Well if we start with all of the stones being turned on, the castle will be floating and relatively stationary (barring the flow of the ley-line and the wind pushing it). What we do next is turn off the stones at the front of the castle, only for a fraction of a second, which will cause the castle to tilt slightly forwards. The force of gravity will start pulling the castle downwards on that side, pulling it forward. To prevent us from crashing, we turn the stone back on, floating us back up, only now we are slightly further forward. If we keep repeating this process rapidly, we will soon start to build up significant speed, despite the castles high mass.



                        This concept is very similar to that of the rail gun which uses electromagnetic force to move a metallic object at high speed. Contrary to its name, it is not just intended for weaponry, NASA proposed to use a rail gun to accelerate small aircraft or spacecraft into orbit..






                        share|improve this answer









                        $endgroup$


















                          1












                          $begingroup$

                          Ley-Line Canals



                          An image of the Segovia Aqueduct
                          https://commons.wikimedia.org/wiki/File:Segovia_Aqueduct.JPG



                          Your castles may float along dedicated canals which are specifically built to allow for floating castles to navigate them. The Romans famously built aqueducts for transporting water, if you built something similar, it would allow for you to easily transport your castles around.



                          The canals would be constructed along the paths of the ley-lines, essentially acting as guides to prevent the castle from drifting away from the ley-line. This also means you will not accidentally drift into a “dead zone” where the stones do not float at all, which would cause a castle to crash.



                          Sails



                          Canals alone though wont cause you to move forward. Instead, as you are now floating along fixed lines, like a railroad track, you can now safely use sails to push you forwards. Before, without he canal, you risked being pushed out of the ley-line. Now though, as you are more firmly fixed into the line, there is significantly less of a chance for you to be pushed out, most momentum from the wind should push you forwards (assuming you angle your sails correctly and the wind is not blowing in the complete opposite direction you want to go).



                          Wheels



                          Alternatively, you might opt to use wheels to move your castles. Wheels would run along grooves in the canal and could be powered through a number of ways, such as by man power, using beasts of burden or even with falling water like a watermill. Don’t expect the castle to move particularly quickly though.



                          One problem with the concept of using canals though is they would take a very long time to build everywhere. Perhaps you only have canals on major routs, such as between cities (much like how highways only run between large cities and smaller towns build up along those routs). You could also take from the idea of shipping lanes where canals are only built on well-established and often used routs.



                          Magnetism



                          Essentially, your castles could work like levitating trains. Your stones would work like magnets, repelling away from the ley-line which causes them to float. If you can invert that signal, causing them to be pulled towards the ley-line rather than being pushed away, you could propel yourself through the power of magnetism (not really magnets per say but they function similarly enough).



                          The way magnetic trains work is by turning on and off magnets in a certain order, causing the train to be pulled forward. Your stones could be turned on and off, when they are on, they float on the ley-line, when they are off, they fall.



                          So how can we turn this into forward movement? Well if we start with all of the stones being turned on, the castle will be floating and relatively stationary (barring the flow of the ley-line and the wind pushing it). What we do next is turn off the stones at the front of the castle, only for a fraction of a second, which will cause the castle to tilt slightly forwards. The force of gravity will start pulling the castle downwards on that side, pulling it forward. To prevent us from crashing, we turn the stone back on, floating us back up, only now we are slightly further forward. If we keep repeating this process rapidly, we will soon start to build up significant speed, despite the castles high mass.



                          This concept is very similar to that of the rail gun which uses electromagnetic force to move a metallic object at high speed. Contrary to its name, it is not just intended for weaponry, NASA proposed to use a rail gun to accelerate small aircraft or spacecraft into orbit..






                          share|improve this answer









                          $endgroup$
















                            1












                            1








                            1





                            $begingroup$

                            Ley-Line Canals



                            An image of the Segovia Aqueduct
                            https://commons.wikimedia.org/wiki/File:Segovia_Aqueduct.JPG



                            Your castles may float along dedicated canals which are specifically built to allow for floating castles to navigate them. The Romans famously built aqueducts for transporting water, if you built something similar, it would allow for you to easily transport your castles around.



                            The canals would be constructed along the paths of the ley-lines, essentially acting as guides to prevent the castle from drifting away from the ley-line. This also means you will not accidentally drift into a “dead zone” where the stones do not float at all, which would cause a castle to crash.



                            Sails



                            Canals alone though wont cause you to move forward. Instead, as you are now floating along fixed lines, like a railroad track, you can now safely use sails to push you forwards. Before, without he canal, you risked being pushed out of the ley-line. Now though, as you are more firmly fixed into the line, there is significantly less of a chance for you to be pushed out, most momentum from the wind should push you forwards (assuming you angle your sails correctly and the wind is not blowing in the complete opposite direction you want to go).



                            Wheels



                            Alternatively, you might opt to use wheels to move your castles. Wheels would run along grooves in the canal and could be powered through a number of ways, such as by man power, using beasts of burden or even with falling water like a watermill. Don’t expect the castle to move particularly quickly though.



                            One problem with the concept of using canals though is they would take a very long time to build everywhere. Perhaps you only have canals on major routs, such as between cities (much like how highways only run between large cities and smaller towns build up along those routs). You could also take from the idea of shipping lanes where canals are only built on well-established and often used routs.



                            Magnetism



                            Essentially, your castles could work like levitating trains. Your stones would work like magnets, repelling away from the ley-line which causes them to float. If you can invert that signal, causing them to be pulled towards the ley-line rather than being pushed away, you could propel yourself through the power of magnetism (not really magnets per say but they function similarly enough).



                            The way magnetic trains work is by turning on and off magnets in a certain order, causing the train to be pulled forward. Your stones could be turned on and off, when they are on, they float on the ley-line, when they are off, they fall.



                            So how can we turn this into forward movement? Well if we start with all of the stones being turned on, the castle will be floating and relatively stationary (barring the flow of the ley-line and the wind pushing it). What we do next is turn off the stones at the front of the castle, only for a fraction of a second, which will cause the castle to tilt slightly forwards. The force of gravity will start pulling the castle downwards on that side, pulling it forward. To prevent us from crashing, we turn the stone back on, floating us back up, only now we are slightly further forward. If we keep repeating this process rapidly, we will soon start to build up significant speed, despite the castles high mass.



                            This concept is very similar to that of the rail gun which uses electromagnetic force to move a metallic object at high speed. Contrary to its name, it is not just intended for weaponry, NASA proposed to use a rail gun to accelerate small aircraft or spacecraft into orbit..






                            share|improve this answer









                            $endgroup$



                            Ley-Line Canals



                            An image of the Segovia Aqueduct
                            https://commons.wikimedia.org/wiki/File:Segovia_Aqueduct.JPG



                            Your castles may float along dedicated canals which are specifically built to allow for floating castles to navigate them. The Romans famously built aqueducts for transporting water, if you built something similar, it would allow for you to easily transport your castles around.



                            The canals would be constructed along the paths of the ley-lines, essentially acting as guides to prevent the castle from drifting away from the ley-line. This also means you will not accidentally drift into a “dead zone” where the stones do not float at all, which would cause a castle to crash.



                            Sails



                            Canals alone though wont cause you to move forward. Instead, as you are now floating along fixed lines, like a railroad track, you can now safely use sails to push you forwards. Before, without he canal, you risked being pushed out of the ley-line. Now though, as you are more firmly fixed into the line, there is significantly less of a chance for you to be pushed out, most momentum from the wind should push you forwards (assuming you angle your sails correctly and the wind is not blowing in the complete opposite direction you want to go).



                            Wheels



                            Alternatively, you might opt to use wheels to move your castles. Wheels would run along grooves in the canal and could be powered through a number of ways, such as by man power, using beasts of burden or even with falling water like a watermill. Don’t expect the castle to move particularly quickly though.



                            One problem with the concept of using canals though is they would take a very long time to build everywhere. Perhaps you only have canals on major routs, such as between cities (much like how highways only run between large cities and smaller towns build up along those routs). You could also take from the idea of shipping lanes where canals are only built on well-established and often used routs.



                            Magnetism



                            Essentially, your castles could work like levitating trains. Your stones would work like magnets, repelling away from the ley-line which causes them to float. If you can invert that signal, causing them to be pulled towards the ley-line rather than being pushed away, you could propel yourself through the power of magnetism (not really magnets per say but they function similarly enough).



                            The way magnetic trains work is by turning on and off magnets in a certain order, causing the train to be pulled forward. Your stones could be turned on and off, when they are on, they float on the ley-line, when they are off, they fall.



                            So how can we turn this into forward movement? Well if we start with all of the stones being turned on, the castle will be floating and relatively stationary (barring the flow of the ley-line and the wind pushing it). What we do next is turn off the stones at the front of the castle, only for a fraction of a second, which will cause the castle to tilt slightly forwards. The force of gravity will start pulling the castle downwards on that side, pulling it forward. To prevent us from crashing, we turn the stone back on, floating us back up, only now we are slightly further forward. If we keep repeating this process rapidly, we will soon start to build up significant speed, despite the castles high mass.



                            This concept is very similar to that of the rail gun which uses electromagnetic force to move a metallic object at high speed. Contrary to its name, it is not just intended for weaponry, NASA proposed to use a rail gun to accelerate small aircraft or spacecraft into orbit..







                            share|improve this answer












                            share|improve this answer



                            share|improve this answer










                            answered 4 hours ago









                            Liam MorrisLiam Morris

                            4,332642




                            4,332642























                                0












                                $begingroup$

                                You should be able to sail the castle, the issue would be sail material, you'd be using bamboo, timber and metal rather than cloth because the structures are going to be too large for traditional fabric. Controlling sails that large will be challenging but not impossible, I'd think that capstan and treadwheel driven winches would be sufficient.






                                share|improve this answer











                                $endgroup$









                                • 1




                                  $begingroup$
                                  Sailing only works because the hull of the boat is in the sea and can provide lateral resistance. Similarly, landsailing works because the wheels provide lateral resistance. Free-floating objects with sails will simply blow downwind. If the wind is blowing along your Line then you're in luck, otherwise you simply cannot use sails at all.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  @StarfishPrime Of course you can, you can play the pressure on different sets of sails off each other to get differential movement, also the ley line current will act as the differential current against the winds that you need to get movement out of sails in any vessel.
                                  $endgroup$
                                  – Ash
                                  7 hours ago










                                • $begingroup$
                                  You will, at best, be able to slightly change your downwind vector. The OP explicitly states that castles are able to drift from their Lines, and as such you clearly cannot rely on them to provide a stabilising force of any useful magnitude.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  Starfish Prime is correct about this. This is the reason sails have never been used on zeppelins/blimps (outside of fanciful airships from video games and animes etc.)
                                  $endgroup$
                                  – Qami
                                  6 hours ago
















                                0












                                $begingroup$

                                You should be able to sail the castle, the issue would be sail material, you'd be using bamboo, timber and metal rather than cloth because the structures are going to be too large for traditional fabric. Controlling sails that large will be challenging but not impossible, I'd think that capstan and treadwheel driven winches would be sufficient.






                                share|improve this answer











                                $endgroup$









                                • 1




                                  $begingroup$
                                  Sailing only works because the hull of the boat is in the sea and can provide lateral resistance. Similarly, landsailing works because the wheels provide lateral resistance. Free-floating objects with sails will simply blow downwind. If the wind is blowing along your Line then you're in luck, otherwise you simply cannot use sails at all.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  @StarfishPrime Of course you can, you can play the pressure on different sets of sails off each other to get differential movement, also the ley line current will act as the differential current against the winds that you need to get movement out of sails in any vessel.
                                  $endgroup$
                                  – Ash
                                  7 hours ago










                                • $begingroup$
                                  You will, at best, be able to slightly change your downwind vector. The OP explicitly states that castles are able to drift from their Lines, and as such you clearly cannot rely on them to provide a stabilising force of any useful magnitude.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  Starfish Prime is correct about this. This is the reason sails have never been used on zeppelins/blimps (outside of fanciful airships from video games and animes etc.)
                                  $endgroup$
                                  – Qami
                                  6 hours ago














                                0












                                0








                                0





                                $begingroup$

                                You should be able to sail the castle, the issue would be sail material, you'd be using bamboo, timber and metal rather than cloth because the structures are going to be too large for traditional fabric. Controlling sails that large will be challenging but not impossible, I'd think that capstan and treadwheel driven winches would be sufficient.






                                share|improve this answer











                                $endgroup$



                                You should be able to sail the castle, the issue would be sail material, you'd be using bamboo, timber and metal rather than cloth because the structures are going to be too large for traditional fabric. Controlling sails that large will be challenging but not impossible, I'd think that capstan and treadwheel driven winches would be sufficient.







                                share|improve this answer














                                share|improve this answer



                                share|improve this answer








                                edited 7 hours ago

























                                answered 8 hours ago









                                AshAsh

                                28.9k471159




                                28.9k471159








                                • 1




                                  $begingroup$
                                  Sailing only works because the hull of the boat is in the sea and can provide lateral resistance. Similarly, landsailing works because the wheels provide lateral resistance. Free-floating objects with sails will simply blow downwind. If the wind is blowing along your Line then you're in luck, otherwise you simply cannot use sails at all.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  @StarfishPrime Of course you can, you can play the pressure on different sets of sails off each other to get differential movement, also the ley line current will act as the differential current against the winds that you need to get movement out of sails in any vessel.
                                  $endgroup$
                                  – Ash
                                  7 hours ago










                                • $begingroup$
                                  You will, at best, be able to slightly change your downwind vector. The OP explicitly states that castles are able to drift from their Lines, and as such you clearly cannot rely on them to provide a stabilising force of any useful magnitude.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  Starfish Prime is correct about this. This is the reason sails have never been used on zeppelins/blimps (outside of fanciful airships from video games and animes etc.)
                                  $endgroup$
                                  – Qami
                                  6 hours ago














                                • 1




                                  $begingroup$
                                  Sailing only works because the hull of the boat is in the sea and can provide lateral resistance. Similarly, landsailing works because the wheels provide lateral resistance. Free-floating objects with sails will simply blow downwind. If the wind is blowing along your Line then you're in luck, otherwise you simply cannot use sails at all.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  @StarfishPrime Of course you can, you can play the pressure on different sets of sails off each other to get differential movement, also the ley line current will act as the differential current against the winds that you need to get movement out of sails in any vessel.
                                  $endgroup$
                                  – Ash
                                  7 hours ago










                                • $begingroup$
                                  You will, at best, be able to slightly change your downwind vector. The OP explicitly states that castles are able to drift from their Lines, and as such you clearly cannot rely on them to provide a stabilising force of any useful magnitude.
                                  $endgroup$
                                  – Starfish Prime
                                  7 hours ago










                                • $begingroup$
                                  Starfish Prime is correct about this. This is the reason sails have never been used on zeppelins/blimps (outside of fanciful airships from video games and animes etc.)
                                  $endgroup$
                                  – Qami
                                  6 hours ago








                                1




                                1




                                $begingroup$
                                Sailing only works because the hull of the boat is in the sea and can provide lateral resistance. Similarly, landsailing works because the wheels provide lateral resistance. Free-floating objects with sails will simply blow downwind. If the wind is blowing along your Line then you're in luck, otherwise you simply cannot use sails at all.
                                $endgroup$
                                – Starfish Prime
                                7 hours ago




                                $begingroup$
                                Sailing only works because the hull of the boat is in the sea and can provide lateral resistance. Similarly, landsailing works because the wheels provide lateral resistance. Free-floating objects with sails will simply blow downwind. If the wind is blowing along your Line then you're in luck, otherwise you simply cannot use sails at all.
                                $endgroup$
                                – Starfish Prime
                                7 hours ago












                                $begingroup$
                                @StarfishPrime Of course you can, you can play the pressure on different sets of sails off each other to get differential movement, also the ley line current will act as the differential current against the winds that you need to get movement out of sails in any vessel.
                                $endgroup$
                                – Ash
                                7 hours ago




                                $begingroup$
                                @StarfishPrime Of course you can, you can play the pressure on different sets of sails off each other to get differential movement, also the ley line current will act as the differential current against the winds that you need to get movement out of sails in any vessel.
                                $endgroup$
                                – Ash
                                7 hours ago












                                $begingroup$
                                You will, at best, be able to slightly change your downwind vector. The OP explicitly states that castles are able to drift from their Lines, and as such you clearly cannot rely on them to provide a stabilising force of any useful magnitude.
                                $endgroup$
                                – Starfish Prime
                                7 hours ago




                                $begingroup$
                                You will, at best, be able to slightly change your downwind vector. The OP explicitly states that castles are able to drift from their Lines, and as such you clearly cannot rely on them to provide a stabilising force of any useful magnitude.
                                $endgroup$
                                – Starfish Prime
                                7 hours ago












                                $begingroup$
                                Starfish Prime is correct about this. This is the reason sails have never been used on zeppelins/blimps (outside of fanciful airships from video games and animes etc.)
                                $endgroup$
                                – Qami
                                6 hours ago




                                $begingroup$
                                Starfish Prime is correct about this. This is the reason sails have never been used on zeppelins/blimps (outside of fanciful airships from video games and animes etc.)
                                $endgroup$
                                – Qami
                                6 hours ago


















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