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Miscellaneous Loroi question-and-answer thread 
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Post Re: Miscellaneous Loroi question-and-answer thread
If a Loroi division surprises an Umiak division by waiting on their arrival around their jump sector, how large would be the expected Umiak losses?


Fri Sep 27, 2019 10:27 am
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Post Re: Miscellaneous Loroi question-and-answer thread
Werra wrote:
If a Loroi division surprises an Umiak division by waiting on their arrival around their jump sector, how large would be the expected Umiak losses?

Umiak ships have an advantage in close-range combat, so I don't think it's usually going to be in the Loroi interest to be up close when an Umiak division comes out of jump. The Umiak will be disorganized and disoriented, but it doesn't take a lot of finesse to shoot at targets at close range.

If you could predict exactly where the enemy will appear and position yourself at maximum weapons range, you could do a fair amount of damage, but that would be very difficult -- a normal jump zone for a Sun-like star is as much as 10 light minutes (more than 1 AU) deep, and that's assuming the enemy isn't deliberately short-jumping or deep-jumping.

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Post Re: Miscellaneous Loroi question-and-answer thread
How many Loroi are there?


Fri Sep 27, 2019 3:55 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
Warringrose wrote:
How many Loroi are there?


IIRC, somewhere between 50 and 100 billion...

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Sat Sep 28, 2019 8:03 am
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Post Re: Miscellaneous Loroi question-and-answer thread
I don't have an exact figure.

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Post Re: Miscellaneous Loroi question-and-answer thread
I would assume each Loroi's figure is hand drawn and quite nice.


Sat Sep 28, 2019 5:32 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
Ithekro wrote:
I would assume each Loroi's figure is hand drawn and quite nice.

I think you'll find we all agree :lol:

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Post Re: Miscellaneous Loroi question-and-answer thread
How does acceleration as shown on the insider ship pages break down for the ships.
If it says 27g is that any direction or only a direction the main engines can push, if its only the main engines whats the average acceleration of the maneuvering thrusters?
Also what is the speed of rotation, are the big Loroi caps like fighters capable of turning 180 in a few seconds or are they more weighty taking like 20s to rotate?


Sat Oct 05, 2019 9:38 am
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Post Re: Miscellaneous Loroi question-and-answer thread
MBehave wrote:
How does acceleration as shown on the insider ship pages break down for the ships.
If it says 27g is that any direction or only a direction the main engines can push, if its only the main engines whats the average acceleration of the maneuvering thrusters?
Also what is the speed of rotation, are the big Loroi caps like fighters capable of turning 180 in a few seconds or are they more weighty taking like 20s to rotate?

The listed acceleration is for the main engines, so it applies to the direction that the ship is currently pointed in. Ships can pivot using their maneuvering thrusters and/or by differential thrust or thrust vectoring of the main engines. The pivot rate will be specific to each ship, depending on the strength of its thrusters, the thrust and positioning of its engines, and its mass and shape. Loroi ships usually have two main engines positioned out from the centerline, and so can pivot rapidly by differential thrust of the two engines, though this means reducing overall acceleration during the pivot, since one of the engines must be throttled down. Loroi ships can also do some thrust vectoring of the main engines (as seen on p.81).

Figuring out pivot rates for ships gets complicated, as working out torque and moments of inertia for irregularly-shaped objects is not very straightforward. But the upshot is that inertia increases with the mass times the length of the object squared, and so larger ships will have slower pivot rates even when they have the same net acceleration of the various thrusters. So a battleship can't maneuver as nimbly as a fighter, no matter how big its engines are.

And, of course, we're only talking about rotation here and not "turning" in the sense of a terrestrial ship or car; rotating a spacecraft does not change its momentum, and it's still traveling in the same direction it was before, but now with its nose pointed in a different direction.

I worked out some slightly abstracted pivot rates for the starship combat sim that deal in 60 degree increments and 80 second time segments: in general, the pivot rate for hull types are: destroyer = 3 degrees per 2 seconds, cruiser = 3°/4s, battleship = 3°/8s. (Fighters and gunboats pivot rapidly enough that in terms of the simulation, they can essentially point in any direction at will within the 80 second segment.) Of course, due to acceleration and angular momentum, the rotation rate is not constant, and a pivot of 120° will take less time per degree than a 60° pivot, but that's getting a bit into the weeds...

To take the Scimitar cruiser as an example, in the sim it can rotate 0.75 degrees per second using maneuvering thrusters alone, or up to 2.2 degrees per second using differential thrust of the main engines, in which case it is limited to half maximum acceleration during the pivot.

Umiak vessels have more but smaller main engines and will benefit less from differential thrust, but they tend to be more compactly shaped, and so will have smaller moments of inertia for the same mass than a Loroi ship.

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Post Re: Miscellaneous Loroi question-and-answer thread
Actually thought your ships used reactionless thrust for some reason so the mains worked as good in any direction and the "engine" nozzles was just for heat dissipation on Umiak and Loroi ships.
With those turn rates seems the mains would not do much to help avoid volley fire thats bracketing the area around a ship.
Whats the best acceleration each ship class could give out for say 30 seconds under emergency conditions to a right angle from original facing to try to dodge an area attack like the waveloom or kinetic projectiles?

Arioch wrote:
MBehave wrote:
How does acceleration as shown on the insider ship pages break down for the ships.
If it says 27g is that any direction or only a direction the main engines can push, if its only the main engines whats the average acceleration of the maneuvering thrusters?
Also what is the speed of rotation, are the big Loroi caps like fighters capable of turning 180 in a few seconds or are they more weighty taking like 20s to rotate?

The listed acceleration is for the main engines, so it applies to the direction that the ship is currently pointed in. Ships can pivot using their maneuvering thrusters and/or by differential thrust or thrust vectoring of the main engines. The pivot rate will be specific to each ship, depending on the strength of its thrusters, the thrust and positioning of its engines, and its mass and shape. Loroi ships usually have two main engines positioned out from the centerline, and so can pivot rapidly by differential thrust of the two engines, though this means reducing overall acceleration during the pivot, since one of the engines must be throttled down. Loroi ships can also do some thrust vectoring of the main engines (as seen on p.81).

Figuring out pivot rates for ships gets complicated, as working out torque and moments of inertia for irregularly-shaped objects is not very straightforward. But the upshot is that inertia increases with the mass times the length of the object squared, and so larger ships will have slower pivot rates even when they have the same net acceleration of the various thrusters. So a battleship can't maneuver as nimbly as a fighter, no matter how big its engines are.

And, of course, we're only talking about rotation here and not "turning" in the sense of a terrestrial ship or car; rotating a spacecraft does not change its momentum, and it's still traveling in the same direction it was before, but now with its nose pointed in a different direction.

I worked out some slightly abstracted pivot rates for the starship combat sim that deal in 60 degree increments and 80 second time segments: in general, the pivot rate for hull types are: destroyer = 3 degrees per 2 seconds, cruiser = 3°/4s, battleship = 3°/8s. (Fighters and gunboats pivot rapidly enough that in terms of the simulation, they can essentially point in any direction at will within the 80 second segment.) Of course, due to acceleration and angular momentum, the rotation rate is not constant, and a pivot of 120° will take less time per degree than a 60° pivot, but that's getting a bit into the weeds...

To take the Scimitar cruiser as an example, in the sim it can rotate 0.75 degrees per second using maneuvering thrusters alone, or up to 2.2 degrees per second using differential thrust of the main engines, in which case it is limited to half maximum acceleration during the pivot.

Umiak vessels have more but smaller main engines and will benefit less from differential thrust, but they tend to be more compactly shaped, and so will have smaller moments of inertia for the same mass than a Loroi ship.


Sat Oct 05, 2019 2:32 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
Arioch wrote:
Werra wrote:
If a Loroi division surprises an Umiak division by waiting on their arrival around their jump sector, how large would be the expected Umiak losses?

Umiak ships have an advantage in close-range combat, so I don't think it's usually going to be in the Loroi interest to be up close when an Umiak division comes out of jump. The Umiak will be disorganized and disoriented, but it doesn't take a lot of finesse to shoot at targets at close range.

If you could predict exactly where the enemy will appear and position yourself at maximum weapons range, you could do a fair amount of damage, but that would be very difficult -- a normal jump zone for a Sun-like star is as much as 10 light minutes (more than 1 AU) deep, and that's assuming the enemy isn't deliberately short-jumping or deep-jumping.


Do jumps require the standard military ships in this conflict to dump heat, and recharge its batteries for shields, and weapons? If yes, is it a short time, or lengthy process?


Sat Oct 05, 2019 3:18 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
hi hi

I think in the insider, it is said that the thrusters are semi-reactionless. They still require propellant, but they're able to get an effective exhaust velocity that is higher than the speed of light.

(Also, it's important to note that as long as a ship is moving somewhat perpendicular to the line of fire, they can do some dodging without any turning at all, just by varying their thrust.)


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Post Re: Miscellaneous Loroi question-and-answer thread
MBehave wrote:
Actually thought your ships used reactionless thrust for some reason so the mains worked as good in any direction and the "engine" nozzles was just for heat dissipation on Umiak and Loroi ships.

"Reactionless" just means you don't have to use reaction mass; it doesn't necessarily mean that the thrust can be applied in any direction. The Loroi Floater drives and the Umiak Plastron drives aren't truly reactionless, but they both use inertial damping fields to amplify the effect of reaction mass; they're still blasting propellant out the back.

The Historian "Illusion Drive" is similar to what you described.

MBehave wrote:
With those turn rates seems the mains would not do much to help avoid volley fire thats bracketing the area around a ship.
Whats the best acceleration each ship class could give out for say 30 seconds under emergency conditions to a right angle from original facing to try to dodge an area attack like the waveloom or kinetic projectiles?

To dodge incoming fire, you need to move away from your current predicted location at the time the shot arrives on target. You don't necessarily have to "turn" to do that; you can also increase or decrease your acceleration.

For example, if you're targeting a Scimitar that's running under full 30g acceleration, and she goes into a hard right pivot and throttles down the starboard engine, it will take about 40 seconds to rotate 90 degrees, during which time she will have cut her acceleration along the predicted path instantly in half to 15g and then over the course of that pivot shifting that 15g acceleration on a tangent away from the previous course. Between the reduced forward acceleration and the lateral acceleration as she rotates, her final position after 40 seconds will be approximately 150 km off the predicted position from her previous course.

Voitan wrote:
Do jumps require the standard military ships in this conflict to dump heat, and recharge its batteries for shields, and weapons? If yes, is it a short time, or lengthy process?

Normal weapons fire is usually powered directly from the mains, so this doesn't depend on the state of the batteries used for jump. In Loroi ships, the main deflectors and the jump drive are tied into the same set of batteries, so jump does deplete this system, but only for a few seconds. (In most Umiak ships, they are separate systems.) The main issue for the heat system on most ships is dealing with the heat output from running the engines at full throttle, and this is something that it has to be able to handle continuously for hours on end.

Jump does stress the heat system, but usually not to great degree as regards normal engine and weapons operation. If Tempest tried to do something that further stresses the heat system (like fire her wave-looms) immediately after jumping, that could present a problem.

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Post Re: Miscellaneous Loroi question-and-answer thread
Ahh what?
15g has a displacement of 73.5m over 1 second, velocity is relative and completely irrelevant, a ship capable of thrust at 15g in any direction will have a sphere of uncertainty with a radius of 73.5m over its previously predicted location.
That holds true if its moving at half the speed of light or was stationary relative to the attacker.
Are g in outsider gravity of acceleration or something else?

Volley fire with a bracketed target could be say 3000 kinetic rounds spaced 250m apart against a Umiak Super Heavy.
Don't want to go into it to much because it has to do with Terran Fusion tech and don't want to drag this off topic.

The difference in tech level between the Historian and Loroi almost appears greater then the tech difference between the Terrans and Loroi/Umiak, when Umiak invaded historian space did they actually hit any worlds and recover tech databases or ships?
Seems like even a Historian cargo transport would boost significantly the tech level of the Umiak assuming they could understand it.


Arioch wrote:
MBehave wrote:
Actually thought your ships used reactionless thrust for some reason so the mains worked as good in any direction and the "engine" nozzles was just for heat dissipation on Umiak and Loroi ships.

"Reactionless" just means you don't have to use reaction mass; it doesn't necessarily mean that the thrust can be applied in any direction. The Loroi Floater drives and the Umiak Plastron drives aren't truly reactionless, but they both use inertial damping fields to amplify the effect of reaction mass; they're still blasting propellant out the back.

The Historian "Illusion Drive" is similar to what you described.

MBehave wrote:
With those turn rates seems the mains would not do much to help avoid volley fire thats bracketing the area around a ship.
Whats the best acceleration each ship class could give out for say 30 seconds under emergency conditions to a right angle from original facing to try to dodge an area attack like the waveloom or kinetic projectiles?

To dodge incoming fire, you need to move away from your current predicted location at the time the shot arrives on target. You don't necessarily have to "turn" to do that; you can also increase or decrease your acceleration.

For example, if you're targeting a Scimitar that's running under full 30g acceleration, and she goes into a hard right pivot and throttles down the starboard engine, it will take about 40 seconds to rotate 90 degrees, during which time she will have cut her acceleration along the predicted path instantly in half to 15g and then over the course of that pivot shifting that 15g acceleration on a tangent away from the previous course. Between the reduced forward acceleration and the lateral acceleration as she rotates, her final position after 40 seconds will be approximately 150 km off the predicted position from her previous course.

Voitan wrote:
Do jumps require the standard military ships in this conflict to dump heat, and recharge its batteries for shields, and weapons? If yes, is it a short time, or lengthy process?

Normal weapons fire is usually powered directly from the mains, so this doesn't depend on the state of the batteries used for jump. In Loroi ships, the main deflectors and the jump drive are tied into the same set of batteries, so jump does deplete this system, but only for a few seconds. (In most Umiak ships, they are separate systems.) The main issue for the heat system on most ships is dealing with the heat output from running the engines at full throttle, and this is something that it has to be able to handle continuously for hours on end.

Jump does stress the heat system, but usually not to great degree as regards normal engine and weapons operation. If Tempest tried to do something that further stresses the heat system (like fire her wave-looms) immediately after jumping, that could present a problem.


Sat Oct 05, 2019 9:25 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
MBehave wrote:
15g has a displacement of 73.5m over 1 second, velocity is relative and completely irrelevant, a ship capable of thrust at 15g in any direction will have a sphere of uncertainty with a radius of 73.5m over its previously predicted location.

Volley fire with a bracketed target could be say 3000 kinetic rounds spaced 250m apart against a Umiak Super Heavy.

The Scimitar has a maximum acceleration of 30g, so the value would be 147m in one second. But for kinetic rounds to arrive with a delay of only one second, the firing ship would have to be at extremely close range. The AMM-250 at 400g can only displace about 7,000 km in one second, unless the firing ship had a very high additional relative velocity.

MBehave wrote:
The difference in tech level between the Historian and Loroi almost appears greater then the tech difference between the Terrans and Loroi/Umiak, when Umiak invaded historian space did they actually hit any worlds and recover tech databases or ships?
Seems like even a Historian cargo transport would boost significantly the tech level of the Umiak assuming they could understand it.

The Loroi have very little information about what happened in Historian territory during the Umiak invasion. The Historians appear to have withdrawn from the attacked systems having offered very little resistance, and then retook most of the systems less than a year later, but it's not known what the Umiak found there or what they did during the time those systems were under their control. To this point there has been no indication of a spike in Umiak technology, and when pressed on the subject the Historian envoys would say only that it was not a matter of concern.

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Post Re: Miscellaneous Loroi question-and-answer thread
Thats the main engines which you have stated is directional and the ships are slow to turn... why I was asking what their maneuvering thrust is.
I'm trying to work out effective range for high velocity bust railguns using hydrogen pellets for a fleet battle sim.
As the fleets are closing on each other they only really have lateral thrust to use for avoiding incoming fire since the turn rates for the ships are slow.

Arioch wrote:
MBehave wrote:
15g has a displacement of 73.5m over 1 second, velocity is relative and completely irrelevant, a ship capable of thrust at 15g in any direction will have a sphere of uncertainty with a radius of 73.5m over its previously predicted location.

Volley fire with a bracketed target could be say 3000 kinetic rounds spaced 250m apart against a Umiak Super Heavy.

The Scimitar has a maximum acceleration of 30g, so the value would be 147m in one second. But for kinetic rounds to arrive with a delay of only one second, the firing ship would have to be at extremely close range. The AMM-250 at 400g can only displace about 7,000 km in one second, unless the firing ship had a very high additional relative velocity.

MBehave wrote:
The difference in tech level between the Historian and Loroi almost appears greater then the tech difference between the Terrans and Loroi/Umiak, when Umiak invaded historian space did they actually hit any worlds and recover tech databases or ships?
Seems like even a Historian cargo transport would boost significantly the tech level of the Umiak assuming they could understand it.

The Loroi have very little information about what happened in Historian territory during the Umiak invasion. The Historians appear to have withdrawn from the attacked systems having offered very little resistance, and then retook most of the systems less than a year later, but it's not known what the Umiak found there or what they did during the time those systems were under their control. To this point there has been no indication of a spike in Umiak technology, and when pressed on the subject the Historian envoys would say only that it was not a matter of concern.


Sun Oct 06, 2019 12:08 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
hi hi

Railguns continue to not be very combat effective weapons in the Outsider universe. (Or really any universe with effective beam weapons.)

Also, closing vessels don't need to have their main engines pointed in the axis of movement, they could rotate off axis and still close with their initial momentum.


Sun Oct 06, 2019 4:17 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
I was able to find the calculations that I did regarding pivot rates and angular momentum, and they give very different pivot rates to the ones in the combat sim -- a 60 degree pivot using differential thrust of the main engines alone was calculated at 3.27 seconds for the Scimitar and 4.4 seconds for the Tempest. I don't recall whether I used different values in the sim because I found these to be wrong, or whether I was just fudging for the sake of the Attack Vector sim mechanics (this is from 2005). Here are my notes if you want to check the logic:

Spoiler: show
1 radian is essentially one 60 degree hex face (57.2958 degrees).
For a test, we’d like to know how long it takes for a cylinder of arbitrary dimensions to rotate 1 radian.
So the angular displacement (theta) we’re looking for is 1 rad in 80 sec. Theta = theta0 + ωt.
On a sample cruiser, F = ma, and a = 294 m/s², and m= 350 kt, so F = 102,900,000,000 N. That’s 51,450,000,000 from each engine (F = ma/2).
Torque = force * distance from center of rotation = τ = F*r. For the cruiser, r is about 115 m. So torque is 5,916,750,000,000 Nm.
Let’s pretend the cruiser has a mass distribution of a sphere. I = 2/5 mr² = 2/5*350kt*(417m/2)² = 6,086,115,000,000 kg*m².
Torque is also equal to the Moment of Inertia * angular acceleration (τ = Iα). So α = τ /I = .97 rad/s².
Θ = ½αt². So the rotation in 1 segment is = .97*(80)²/2 = 3104. That’s 177,859.2 degrees, or 494 complete revolutions. Doesn’t sound quite right.
Let’s look at it going the other way. Looking for a Θ of ½ rad (0.52) in 40 seconds (this would be a maneuvering thruster rate), α = 2Θ/t² = 0.00065 rad/s².
τ = Iα = 6,086,115,000,000 kg*m² * 0.00065 rad/s² = 3,955,974,750 Nm.
F = τ/r = 34,399,780.43 N.
a = F/m = 0.098 m/s² = 0.010 G. So the maneuvering thrusters’ acceleration would be .01 G (or .002 (1/500) thrust points). At the system level, this won’t get you anywhere in a reasonable period of time (after one whole day of thrust, you’ll have yourself 2/500 hex/turn of velocity), so you’re effectively crippled if you lose your main drive.

Let’s assume a worst-case moment of inertia, where all the mass of the ship is at 1/2length (208.5m), so I = mr² = 350kt*(208.5)^2 = 15,215,287,500,000. That’s only about twice as much as the previous example. a = t/I = .3889 rad/s/s. Theta = .3889/2*(80)^2 = 1,244 rad = 198 rotations.
Okay. So the total amount of time to rotate 1 hex face and stop (take ½ radian and multiply the total time by 2) = t = 2*sqrt((theta/2) / (.5*alpha))= 2*sqrt(.52 / (.5*.3889)) = 3.27 seconds.

Let’s try the example for Tempest. Here the mass is 1,200 kt, length is 750m, and the axis of thrust is about 200m. The force of one engine is = 1,200kt*298/2 = 178,800,000,000 N. The torque is 35,760,000,000,000 Nm. The worst-case moment of inertia is = 1200kt*( 375^2) = 168,750,000,000,000. So alpha = .212 rad/s/s. t = 2*sqrt(.212) =
.52 rad = ½ * .212 rad/s/s * t²
.52 rad / (½ * .212 rad/s/s) = t²
sqrt(.52 rad / (½ * .212 rad/s/s)) = t
t = 2.2 s. So that’s 4.4 seconds to complete a pivot of 1 hex face.
2 hex faces = 2*sqrt((2.094/2) / (.5*.212)) = 6.28 sec.
3 hex faces (180 degrees) = 2*sqrt((3.14159/2) / (.5*.212)) = 7.7 sec.


The acceleration potential of the maneuvering thrusters is probably somewhere between .01-.1g, which won't displace the ship in any kind of meaningful time that would let you dodge shots. The maneuvering thrusters are for rotating the ship and doing fine maneuvers such as docking, not for lateral acceleration.

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Post Re: Miscellaneous Loroi question-and-answer thread
icekatze wrote:
hi hi

Railguns continue to not be very combat effective weapons in the Outsider universe. (Or really any universe with effective beam weapons.)

Also, closing vessels don't need to have their main engines pointed in the axis of movement, they could rotate off axis and still close with their initial momentum.


Yeah, the projectile speed vs beam speed comparison is pretty damning. I can see two very small niches where railguns could plausibly kick arse:
  • Ridiculously close range, where solid projectiles may be better at getting energy through armour. (Assuming armour has been optimised against beam weapons.) Not sure how you get that close without dying first...
  • Ridiculously long range bombardment of “stationary” targets (I.e. targets on highly predictable trajectories). I assume you could design a sabot launcher which kept the projectile cold (so it doesn’t shine out obvious infrared) and an active terminal guidance suite in to give a couple of gentle nudges in flight.
Both of these are very niche.


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Post Re: Miscellaneous Loroi question-and-answer thread
Actually I was talking to a guy from CERN on hardscifi discord a few days ago.
Think it deserves its own topic so I will continue this conversation there.
But the gist is.
Its easier to accelerate smaller objects then it is to accelerate large projectiles to large energy levels, peak field strength needed to accelerate something like a 2m long 8cm wide tungsten projectile(outsider Terran kinetic projectile mass) is far greater and less efficient then a vastly smaller encapsulated solid hydrogen pellet due to field dropoff over distance. Railguns should attempt over 4000km/s and use hydrogen pellets.
Such weapons if they fire in bursts are effective at outsider combat ranges and beyond when used to fire in volleys and fleets/guns are linked by firecontrol systems.
They also don't use significant amounts of mass.

icekatze wrote:
hi hi

Railguns continue to not be very combat effective weapons in the Outsider universe. (Or really any universe with effective beam weapons.)

Also, closing vessels don't need to have their main engines pointed in the axis of movement, they could rotate off axis and still close with their initial momentum.


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Post Re: Miscellaneous Loroi question-and-answer thread
icekatze wrote:
hi hi

Railguns continue to not be very combat effective weapons in the Outsider universe. (Or really any universe with effective beam weapons.)


There is a reason that the railgun attacks in the Helfort's War books consisted of firing conical spiral bursts (Swarms) of a hundred thousand or so projectiles plus a liberal supply of decoys to minimise the targets ability to use beam weapons to deflect shots or manuever to face low density areas of the swarm.

And then are happy with three or four hits in 96,000 projectiles.

IIRC they are firing at comparatively very low ranges there and have lower acceleration given Helfort survives trailing behind his ship on a cable at one point while it is evading at one point.


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Post Re: Miscellaneous Loroi question-and-answer thread
hi hi

I don't think 3 or 4 hits is going to do much against anyone who has some moderate understanding of how to make hypervelocity resistant armor. Between whipple shields and appropriate sloping, it can take quite a few hits do cause significant damage.


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Post Re: Miscellaneous Loroi question-and-answer thread
A Whipple shield is not magic.
5gram projectile moving at ~18000km/s for example will collapse it and at best still deform the hull, at worst punch through anyways now as super heated plasma.
Can't Reach those speeds in outsider?
This is the velocity off modern day gunpowder weapons vs a Loroi fleet that decided to "charge" Earth.

A perfectly aligned jump with Earth and 4.5au under full thrust at 24g in a flyby attack puts them at 18000km/s

At these speeds ~32000 rounds spaced 50m apart have an effective range against a dodging Loroi Tempest(4.7s 90 degree rotation at 25% lateral acceleration, then 100% lateral acceleration at full thrust)
over 1200000km.
What if we want to waste a million rounds against such a ship at say 20m spaced, effective range of almost 200000km.
Even Earth today could easily handle sending a swarm of BILLIONS of 50 cal rounds, only accuracy is a problem, advanced railguns 160 years down the line designed for space combat should not have that issue.
Of course the launchers would be overtaken by the Loroi fleet shortly after fireing but its just an example of how both projectile and ships speed is important
.
Railguns are not a fleet to fleet weapon unless you can get decent fractional C, they do however work against a high thrust ships by forcing them to burn fuel dodging or limit their maximum system speed. Further if the projectiles are small enough and coated so they are hard to detect fleets have to assume they are underfire and constantly make vector changes further reducing their acceleration ability in straight lines even over short distances.

Rapid fire railguns at Terran outsider speeds of 400km/s with say 1 gram projectiles would significantly limit the intersystem speed hostile fleets ability to charge/retreat under full thrust.
Also ammo is not a problem.
lets say 10000 rounds a minute per gun, after 24 hours of constant use such a gun would only consume 14.4 tons of ammo.
So its not even excessive for a Terran Cruiser to fire constantly for days at a Enemy fleet with such guns just to keep them having to burn reaction mass even if they don't get a single hit.
icekatze wrote:
hi hi

I don't think 3 or 4 hits is going to do much against anyone who has some moderate understanding of how to make hypervelocity resistant armor. Between whipple shields and appropriate sloping, it can take quite a few hits do cause significant damage.


Wed Oct 09, 2019 10:44 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
hi hi

Stationary defenses are already regarded is not very effective in the Outsider universe. The ability to maneuver is very important, and if an attacking fleet is able to fly directly toward your planet without being interdicted, you've already lost that engagement whether you have some out of setting railguns or not.

MBehave wrote:
A Whipple shield is not magic.
I think everyone can agree on this. I don't think that was ever a question.


Wed Oct 09, 2019 11:09 pm
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Post Re: Miscellaneous Loroi question-and-answer thread
I guess this is more a human question, but will there be anything in the Loroi diet that Alex can find edible, or if that is a spoiler, what that he has tried to eat can be eaten and kept down to some success?


Thu Oct 10, 2019 9:40 pm
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