Cinematic Realism, or having Fun with Inertia

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Cinematic Realism, or having Fun with Inertia

Unread post by glitterboy2098 »

one thing many people complain about in Phase World, Mutants in Orbit, Robotech, Aliens Unlimited, and other palladium space settings, is the 'mach in space' movement system and the absurdly low speeds there of.

in robotech i didn't mind much, since my games rarely got into space.
ever since getting phase world, i've been trying to devise a more realistic space travel system while maintaining the cinematic feel of the setting. after several failed attempts, i eventually found a method i liked, and i've been refining it since.

the main idea is Inertia and thrust. Thrust is the ships ability to alter it's velocity, and inertia keeps a ship moving at a velocity when the drives are off.
under this system, ships in combat would accellerate (thrust) to a speed, and then would coast at that velocity while fighting, altering speed only if needed.

this set up also allows for some more interesting combat methods, such as kinetic impactors, the use of reaction drives as weapons, and other such interesting methods.

in addition, it opens up the option of slower than light interstellar travel, which in turn allows for low-tech star nations and very interesting cosmozoans.


i have intentionally designed the system to be directly compatable with palladiums current game mechanics, with minimal modifications needed.


first is the unit of measurement. for simplicity, these are in mach, or the speed of sound, although in space this seems kinda silly.
to make the math easier, i stuck to metric, although those stuck in the imperial mode can use miles and feet if they want. ;)

1 mach = 1079 kph. (674mph)
1 c (speed of light) = 1,000,000 mach.

now, thurst is measured in how many mach a ship can accellerate by in a set period. for referance i have figured out the accelleration in gravities for each listing, so GM's and players can get an idea of how powerful the ships are. also listed are the kinds of drives that generally make use of which thrust profile.

1 mach per melee = 2g's advanced drives (contragrav, torch drive)
1 mach per minute (4 melee's) = .5g's basic drive (fusion drive, orion drive, Photon drive[antimatter drive])
1 mach per hour (240 melee's) = .08g's simple drives (ion, plasma, NERVA)
1 mach per day = .005g's passive drives (light sail, magsail, plasma sail)


now, although light speed is the absolute speed limit, most drives reach a point where the amount of energy used to accellerate is negated by relativity. most won't have the fuel to reach this max velocity, but there are always ways. (note, i am being generous here. these are general catagories, not specifics. GM's feel free to bump these up or down depending on the drive and races tech level.)

advanced drives: .5 c (500,000 mach)
basic drives: .25c (250,000 mach)
weak drives: .10c (100,000 mach)
passive drives: .7c (700,000 mach) (passive drives will need boosting of some sort to reach such speeds before leaving a system)

at these speeds, even a bolt or nail can be a weapon of mass destruction. ships even more so. as a general rule, an object moving at 3kilometers a second does damage equal to it's mass in TNT.
what this means is that for every 10 mach of velocity, an object does 1D6x10md per ton of mass. this damage is applied to both objects in the collision.

powerful reaction drives, such as fusion, antimatter photon drives, and torch drives, are highly destructive. they generate plumes of high temprature gases which provide the propulsive force, and these plumes can cut through ships like a knife through butter.
for these drives, the drive plume extends 1 kilometer per mach of accelleration, and inflicts 1D6x10md per mach of accell for every 1000 ton of mass to anything that enters the plume.
lower tech races have often used fusion drive or photon drive ships as weapons to defeat more advanced enemies by making use of this fact.


the only other major alteration made is weapon ranges. because ships are much faster, weapons must be much farther ranges to compensate. multiply all directfire weapon ranges by x10.
missiles have a velocity of 100x the listed mach #'s, plus the velocity of the firing ship. (missiles are launched with boosters, mass drivers or gravitic railguns to high velocity, and use onboard drives for manuvering only.) at 1 mach, an object covers about .3 kilometers a second, so to find the range of a missile, take it's velocity and divide by 3 to find how many kilometers the missile can travel in one melee attack. note that this comes to about 4.5 kilometers per melee, for those really long range shots.


in a misc. note, normal orbital velocity around a 1 gravity planet like earth is between 20-36 mach. anything less falls back to the planet, anything more escapes the planets pull. a ship can reach orbit if it can sustain 1 mach per melee of accelleration long enough to reach orbital speeds. (many less powerful ships have boosters or special drive modes to allow this.) given how powerful most ships are in phase world and others, this really doesn't matter much, but for settings like Aliens Unlimited, Robotech, and Mutants in Orbit this can help define which ships cannot enter an atmospere.

----
on a GM's note, those who don't wish to use the term mach should feel free to rename it to whatever they feel is best.

please let me now if there is anything you think i should add to this.

(edit: added a modifier to the fusion plume to reflect that bigger ships mean more damaging drives)
Last edited by glitterboy2098 on Mon Apr 09, 2007 3:43 pm, edited 1 time in total.
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Unread post by Greyaxe »

How has this gone in your group. The slow sublight combat has always been a pet peve of mine. Is this math difficult to keep track of?
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Unread post by glitterboy2098 »

Greyaxe wrote:How has this gone in your group. The slow sublight combat has always been a pet peve of mine. Is this math difficult to keep track of?


AtM, i don't have a group, so i really haven't tested it yet. (part of the reason for posting it here.)

i have played other games that have a similar set up, and those go pretty well. since most of those are miniatures games foremost, they don't work exactly the same though. (this is highly simplified compared to most mini's games, since mini's games can get away with full vector movement.)


as for the math, most of it is simple. you merely keep track of the vessels velocity on a scrap of paper or sheet. if the ship accellerates, merely add the amount of velocity gained at the beginning of the appropriate turn.

although i've listed the 'speed limits' in hundreds of thousands of mach, most combat would occur with relitive velocities of only a few dozen ot a hundred mach differance, and the majority would involve ships matching speeds.



generally unless the ship is mach per melee or mach per minute, it won't be accellerating in combat at all. those exist more to help GM's figure out out of of combat travel times. (travel time is basically the time it takes to accellerate up to speed, the time it takes to cross x distance, and the time it takes to decell. so to travel from earth to mars, a distance of about 3.5 lightminutes. lets say you choose to do it at 100,000 mach (10%c, or .1c), so you can reach it in 35 minutes. in a ship able to accellerate at 1 mach per melee, it would take 100,000 melees to reach that (100,000/1), or 17.36 days. so your total travel time (accell, transit, decell) would be about 35 days.

this math can be punched into a calculator pretty quick (especially if one has a scientific or graphing calc).


in combat situations, you can fudge as well, not having either side acell or decell much, only manuvering. (this would give combat something of a 'new battlestar galactica' or 'babylon 5' feel, with fighters mostly focusing on manuvering and not really changing velocities.)


i would imagine the hardest part would be players wrapping their heads around the inertia based set up. but once they get the hang of it, i'd bet they'd refuse to go back. :)


glitterboy... PS... light sped is not 1 million times the speed of sound. It is about 871,771 times the speed of sound.

check the values again. i redefined palladium's mach to 1079kmh.
figured by taking the speed of light (1,079,252,848.8 km/h) and dividing it by 1,000,000. (actual result is 1079.25, but i rounded to 1079 for simplicity.)

the alternative was a value for the speed of light that was not a nice round number divisable by 100, which would make figuring the %c used in fluff details harder.
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Unread post by glitterboy2098 »

Darkmax wrote:oh... i was using the real world sea level mach speed.


i figured. :) nice to know people were checking.

no other thoughts?

i'm thinking about adding a section on 'psuedo-vector' movement, like you see in Babylon 5 or the new Battlestar galactica. facing one way while moving another, ect. i call it psuedo vector because unlike real vector you could pull off the banking turns and other atmospheric manuvers as well, and you can ignore thrust bookeeping for things like turns and orbit changing.
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Unread post by kamikazzijoe »

Darkmax wrote:I do not know if you are familiar with Wing Commander the game series.

They have this very neat maneuver where the vessel continues on its forward motion but is able to spin around..... I think they named it sliding.

That would be one way to use vectoring jets without altering the course of the vessel.


That sliding is the reason the ideal space fighter would be shaped like a flying saucer. The turret would be omni directional in its 180 of the sphere and the internal drives could be spun to apply thrust in any direction rapidly.

Personally in my phase world games i use my old battletech hex-board and say every hex is 1 mile and you get 1 movement per mach. When you move into some one else's spot you can burn one movement to try and get closer. After rolling opposed piloting skill (or zero g movement skill for CKs and the like), the two are either 1000 feet closer or further.
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Unread post by Rallan »

Right, while you're working on that, who wants to retool the stupidly short range and low damage of ship weapons in the setting? :)
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Unread post by glitterboy2098 »

Darkmax wrote:I do not know if you are familiar with Wing Commander the game series.

They have this very neat maneuver where the vessel continues on its forward motion but is able to spin around..... I think they named it sliding.

That would be one way to use vectoring jets without altering the course of the vessel.


thats one of the things i was reffering to. Wing Commander was more of a 'star wars' type game, having played a bit, but 'sliding' is exactly the sort of thing i include in the 'psuedo-vector' above. 'offset facing' is another term for it.

you ride your momentum, swiviling your craft around at angles to your line of movement.

i figued that under Psuedo movement, you can do that, and then thrust to immediately redirect your line of movement to the new direction. like you see in B5 or NBSG. no need to figure parabolic arcs and the like, as you would in real orbital mechanics. thats one handwave i have no problem with. or you can pull the 'star warsy' banks, turns, and the like as well, using your ships manuvering thrusters to alter direction as opposed to the main drive.

i figure CG fighters have an advantage there, since a CG drive could decellerate without having to first direct the exhust 'ahead' of the line of travel. which would mean a much more manuverable ship.


Right, while you're working on that, who wants to retool the stupidly short range and low damage of ship weapons in the setting?

done...

the only other major alteration made is weapon ranges. because ships are much faster, weapons must be much farther ranges to compensate. multiply all directfire weapon ranges by x10.
missiles have a velocity of 100x the listed mach #'s, plus the velocity of the firing ship. (missiles are launched with boosters, mass drivers or gravitic railguns to high velocity, and use onboard drives for manuvering only.) at 1 mach, an object covers about .3 kilometers a second, so to find the range of a missile, take it's velocity and divide by 3 to find how many kilometers the missile can travel in one melee attack. note that this comes to about 4.5 kilometers per melee, for those really long range shots.


obviously this would need some modification based on setting. the above is good for the 3g's. Robotech ranges only need the above for normal stuff, not the main guns. Aliens unlimited has decent ranges already, IIRC. MiO needs 100x on normal weapons and 1000x on the kill sats. (they are that bad...) (kill sats would also need an extra 0 added to damages...)
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Unread post by kamikazzijoe »

I'll never forget the first time in space some one grabbed hold of another PC he was fighting with and decided to "Fly to the sun and throw him in". Well seeing how he could only travel mach 5 they'd be dead of old age before he got there.
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Unread post by Rallan »

kamikazzijoe wrote:I'll never forget the first time in space some one grabbed hold of another PC he was fighting with and decided to "Fly to the sun and throw him in". Well seeing how he could only travel mach 5 they'd be dead of old age before he got there.


Should've equipped their ship with a traction drive. It's about the only drive in Phase World or Mutants In Orbit that makes travel within a solar system remotely practical (and boy howdy does it go a lot faster than they realised back when they wrote MiO).
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Unread post by glitterboy2098 »

Rallan wrote:
kamikazzijoe wrote:I'll never forget the first time in space some one grabbed hold of another PC he was fighting with and decided to "Fly to the sun and throw him in". Well seeing how he could only travel mach 5 they'd be dead of old age before he got there.


Should've equipped their ship with a traction drive. It's about the only drive in Phase World or Mutants In Orbit that makes travel within a solar system remotely practical (and boy howdy does it go a lot faster than they realised back when they wrote MiO).


by Traction drive you mean the Spatial Catapiller drive that grabs a chunk of space, knots it, pulls it through the drive, releases it, repeat adnausium?
last i knew it only existed in theory, we can't manipulate space to that degree. (you may be mistaking it for the 'hyperdrive' theory recently put out where ultrahigh magnetic feilds [in the 'fry every life form in the solar system with one ship' level] will pull a ship into another level of space where it can exceed the speed of light...)

2nd, no drive can be 'faster' than another. more thrust maybe, or higher Isp, but not 'faster' velocity is a function of distance/time, and their is no limit on velocity in space save for what einstein imposes. thrust = accelleration =an increase/decrease in velocity. if i have a rocket able to thrust at 1g of accelleration, in theory i can reach .9999999999% the speed of light in only 365 days. (my whole point of moving to an inertia based system for space for palladium is because of this 'no limit' reality.


as for opening up the solar system, Fusion will do that, NERVA will do that too, though not as well, Plasma will do that, heck even Continious boost Ion drive will do that, if you don't mind months of travel. just about anything with higher thrust or higher Specific Impulse (Isp) than the Chemical rockets we currently have.
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Unread post by glitterboy2098 »

Darkmax wrote:Traction drive sounds just like CG....


i'd say they are related technologies. Traction drive operates by 'draging' the ship through space, like if you were to pull yourself across a floor with your fingernails.

CG drive operates by 'pushing' a ship through space at the edge of a wave of altered space-time. like surfing a wave.

both require the ability to control the fabric of space through manipulating gravity-like effects.

Traction drive very likely predates a true CGdrive in most cultures, since traction drive would be simpler to pull off. the math and theory behind the manipulation of space for the drive very likely forms the basis for the methods of the CGdrive.
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Unread post by glitterboy2098 »

Darkmax wrote:perhaps traction drive is the fore-runner, the granddaddy of the CG-Drive.

thats one way to look at it. :-D

probably a sequence like
Reaction drive (Fusion or Antiimatter Photon Drive)
Traction Drive
CG FTL drive
CG Sublight drive
CG Dual FTL/Sublight drive

since a sublight CG drive is basically a greatly reduced strength FTL drive, i imagine the FTL version would be first, followed by the Sublight drive as the theory and technology is refined. a dual mode drive would be the final result.
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Unread post by glitterboy2098 »

Darkmax wrote:shouldn't sublight comes before the FTL?


you could run it that way.

i just figure that the sublight mode requires more fine control and efficency than the FTL mode. so the FTl mode would be perfected first, and then the Sublight would be developed from that.
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Unread post by glitterboy2098 »

Darkmax wrote:have you gone and read the entry on Star Trek's FTL and sublight propulsion in Wiki?.... It's under Warp Factor I think. Very interesting to know that at least a part of the sublight system still uses thrusters from conventional means.

And I just got to know that maximum sublight in ST is 1/4c!!! I always thought it would have to be as close to 3/4c.....


actually, Star Trek Impulse Drive is purely newtonian and Einstenian, with a maximum velocity of just under the speed of light (and by just under, i mean always just under), and relies almost entirely on a fusion drive. (augmented by the use of subspace feilds for mass reduction, getting hyper efficency)

the 1/4th c thing was created for the Techmanual by Okuda, but not only contradicted Roddenberry's work (see the .5c prior to the wormhole in the Motion Picture, and the .8c afterwards), and later works in DS9 and Voyager.

the tech manual is not canon, and nearly all the material in it has been since contradicted by material from the show. (there is a little left that is canon, there is an Enterprise that is Galaxy class and captained by Jean-Luc Picard....)


sorry, as you probably already known i am a trekkie, and sometimes the Techmanual fallacies get to me.
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Unread post by glitterboy2098 »

Darkmax wrote:May you live long and prosper. :D I'm a Trek fan too! :D


I didn't know the tech manual is no longer canon!!! Damn... and I spend so much on it! Curse, Okuda!


it never was. no written star trek works are canon. only the 10 movies and the 5 series.
places like Wikipedia and memory-alpha (the ST wiki) allow written works like the tech manual as 'secondary sources', meaning non-canon but can be used in articles.

i have the tech manual, plus the DS9 one, as well as the old Franz Joseph TOS one. they are good reads, just represent that authors vision of the show, not the show itself.

ok, back on topic....:)
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Unread post by glitterboy2098 »

Darkmax wrote:damn waste of money then


not really. they come close, it's just a case of later writers not reading them. :)

they are still good books, and you have to be a total nerd like me to notice anything wrong at all.

though i like to read them for idea's.
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Unread post by glitterboy2098 »

ok, back on topic.
since i want to keep this fairly simple, the guide for 'psuedo-vector' movement.

while coasting (known as 'cruising' to many pilots), a craft can alter it's bearing at angles to it's direction of movement, meaning it can point it's bow somewhere other than directly towards where it is travelling.
using the main engines, this can allow the craft to rapidly change direction with only a little thrust. a full period of accelleration brings the craft onto the new path, with the normal change of velocity.
however, there is a limit to this. first, if the new course is more than 90 degrees from the current direction of travel, the accelleration will become decelleration, reducing the crafts velocity instead of increasing it, and if you change your bearing 180 degrees (placing your engines directly along the path of travel), you will only deccellerate, and not change your direction of travel.
second, the larger the craft, the longer it will take to swing the craft to a new heading. a fighter can chage heading rapidily, in only a few seconds. a cruiser, being larger and more massive, will take longer, up to a whole melee. truely large vessels like battleships and packmaster carriers are more massive still, and will take up to 1 minute to change heading. as a result, large vessels rarely engage in such high-energy manuvers.


(this glosses over some aspects of orbital mechanics, but should produce a workable version of the stuff you see in B5 and the New BSG. )


some examples of what i mean can be seen Here and Here. i'm still looking for decent B5 examples.
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Unread post by glitterboy2098 »

GB, nicely done. Is that what its called, "coasting"? This maneuver can be executed with the main engine off.


it's not an official term. not sure what the 'official' term would be.

the battletech players i know call it 'coasting', in the new BSG they called it 'cruising', you mentioned 'sliding' for Wingcommander, they all refer to mostly the same thing. i imagine there are more too.
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Unread post by Sgt Anjay »

One factor does have to be considered that hasnt been brought up....

The fighters/ships can pull all kinds of wacky maneuvers at crazy high speeds because theres no top speed in space. All well and good. Doesn't mean much if the maneuver turns the the pilot/crew into a nice red (or whatever color) smear on the inside of the craft because that same inertia you're bringing up smashes them to pieces.

In other words, there is a practical top speed if you want to maneuver without causing harm to whoever's inside the craft, and the crazier the maneuver the lower the speed you can pull it off at. So top speed in space may be more a matter of safety limiters built into craft as opposed to limits imposed by physics.
Of course, that opens a can of worms......can MDC pilots take higher speed maneuvers because their bodies can take more punishment? Does this mean robotic/full cyborg pilots also have an advantage? And so on....
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Unread post by glitterboy2098 »

Sgt Anjay wrote:One factor does have to be considered that hasnt been brought up....

The fighters/ships can pull all kinds of wacky maneuvers at crazy high speeds because theres no top speed in space. All well and good. Doesn't mean much if the maneuver turns the the pilot/crew into a nice red (or whatever color) smear on the inside of the craft because that same inertia you're bringing up smashes them to pieces.


yes, G-forces. the bane of fighter pilots. but it's not inertia that does it, it's the centripical forces and the accelleration.

the human body can withstand up to 6-7 G's over short periods (a few seconds), and 2G for extended periods (minutes to hours).
the problem is that in a climb, dive, or turn, these effects pull blood to or from the head, leading to redout (blood to the head) or blackout (blood from the head). when just accellerating, the blood 'pools' towards the accelleration, which has health issues. (try staying in bed for months on end and you'd see what i mean. thats why in some hospitals they have those rotating beds...)

for a fighter, which experiances high G-forces for only a short period (in combat), it's not much of an issue. rarely does the pilot get exposed to life threatening stress for long. especially if it's reaction drive fighter like a Veritech. because your fuel would be limited, dogfights would be rare, and most fighters would be 'missile buses', platforms designed to deliver masses of missiles to a target. battles would be craft lobbing masses of missiles at each other. (watch the beginning of Robotech new Generations for an example). if you engage in a gun fight, your not going to manuver much, just enough to get you past a target where you can 'turret' your craft to shoot the enemy.

for bigger reaction drive ships, accellerations would not be much more than 2 mach per minute normally, and 1 mach per melee in combat. same issues. you lack the fuel to do much manuvering, so combat tends to be either massed missile volleys, or lots of turreted guns.

but the 3G's mastery of gravity means a different story. first, it means Inertial dampening, or the reduction of G-forces on the crew. instead of being limited to only 2-3 G's, your now able to pull manuvers more like 200 G's! plus, your drives are reactionless, requiring no fuel, only power, meaning you have energy to burn for manuvering. you can accellerate more and at higher rates, and dodge around the battle feild. a true 'dogfight' is possible, where fighters are no longer just piloted missile boxes.

for big ships, it's the same story. you can accellerate more and better, for longer periods. you have no fuel limit, so you can manuver more than just getting to a new orbit. with smaller ships (frigates and the like), you can even consider trying the same 'dogfight' tactics of the fighters, but on a slower scale (big ships manuver slower due to mass.)

as for borgs, juicers, and G-forces, use the rules from the Rifter (#34 i think?) it has a great article on air combat. most of the same issues apply.
Last edited by glitterboy2098 on Wed Apr 11, 2007 5:07 pm, edited 1 time in total.
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Unread post by glitterboy2098 »

Darkmax wrote:BTW... shouldn't the forces at work be Centrifugal Force?


Nope
Centripetal force should not be confused with centrifugal force. The centrifugal force is a fictitious force that arises from being in a rotating reference frame. To eliminate all such fictitious forces, one needs to be in a non-accelerating reference frame, i.e., in an inertial reference frame. Only then can one safely use Newton's laws of motion, such as F = ma.


but the Centrifugal force is a related effect.
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Unread post by Sgt Anjay »

Are the inertial dampeners discussed anywhere, or are we using assumption? Also, would full CG be neccesary? The Robotech universe, for example, does not use contragrav, but does have mastery of antigravity and artificial gravity.
Still, intertial dampeners might raise the top practical speed, but unless they have unlimited effectiveness there is an upper limit to how fast you can move and maneuver effectively.

BTW, how many fighters actually use CG? Fighters with any kind of CG seem pretty rare all in all, and its possibly they're too small to house dampeners as well as cg-drives. Most seem to rely on reaction thrusters, which means their top speeds in combat are limited as stated before.

And the question still remains of MDC pilots; can their bodies take greater G's, giving them an advantage?
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Unread post by glitterboy2098 »

Sgt Anjay wrote:Are the inertial dampeners discussed anywhere, or are we using assumption? Also, would full CG be neccesary? The Robotech universe, for example, does not use contragrav, but does have mastery of antigravity and artificial gravity.
Still, intertial dampeners might raise the top practical speed, but unless they have unlimited effectiveness there is an upper limit to how fast you can move and maneuver effectively.


ok, your argueing two different things here.
1st, their is no 'top speed' in space, except that of light itself. you can accellerate in space, increasing your velocity over time, but their is nothing that can limit you in velocity. remember, no friction. so any velocity you gain, you keep. you only need to turn the drive on to accellerate.

2nd, G-forces are a factor of 'manuver', not speed. accelleration generates the effect of gravity, but thats not the issue. what you are argueing is that a fighter when turning creates G-force effect. this is because you, according to the laws of momentum, want to go in a straight line, while the fighter you are in is being pushed around in an arc. this is centripital force.
you feel 'centrifugal force', which feels like gravity, when you hit the fighter you are in and you cannot move further in a straight line. you are 'dragged' along under the accelleration that is allowing your fighter to perform its arc. this is G-force.

the faster you are traveling, the more G-force you may experiance. but the big variable is how fast you are changing course. if you do a tight turn in a fighter, you run the risk of a blackout. the faster you go, the more likely you will blackout. this is because the faster you go, the more accelleration is needed to change your course, and this accelleration increases the more faster you change course.

if you pull a 5 degree turn in 15 seconds, the force might be low. if you pull it in 3 seconds, the forces will be much much higher. this is because the amount of energy is the same, but the faster turn means it is spent over a shorter period of time, meaning a larger accelleration rate over that time. at high velocity, things are worse. to alter your course, you have to put enough energy into the right directions to effect the change. the faster you are going, the more more energy you must use to effect the change. and the tighter the turn, the shorter the period in which to impart it. thus the greater the accelleration, and thus the greater the G-force.

the slower you go, the tighter you can turn, because the energy needed is less, which means less G-force.


as you can see, this is a very complicated issue, and for good reason i chose to gloss over it in favor of playable mechanics. :)
since it isn't hard to imagine that all pilots will have at least G-suits, if not fluid filled cockpits or inertial dampeners, the issue isn't a big one anyway.

BTW, how many fighters actually use CG? Fighters with any kind of CG seem pretty rare all in all, and its possibly they're too small to house dampeners as well as cg-drives. Most seem to rely on reaction thrusters, which means their top speeds in combat are limited as stated before.


actually, in phase world, 90% of space craft in the 3 galaxies use CG drives. that includes all the canon fighters.
MiO has no fighters, AU has fighters (with a range of drives) but i beleive it specifies inertial dampening, robotech has fighters with reaction drives and no mention of inertial dampening.

and their is no such thing as 'top speed' in space.
And the question still remains of MDC pilots; can their bodies take greater G's, giving them an advantage?
yes, their bodies can withstand more G-forces.
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Unread post by Sgt Anjay »

If speeds above a certain point restrict your ability to maneuver to the point where any simple turret A.I. can telegraph your course and shoot you down like child's play, and pulling combat maneuvers at, say, mach 15 (just throwing out numbers) causes you to black out, and doing so at, say, 20 causes you to hemorrhage internally and die, then for all intents and purposes there is a top combat speed. Maybe its imposed by your fighter (if you go too fast you cant maneuver quickly and become a sitting duck), maybe its imposed by your biology (too many Gs and you're a casualty without ever getting hit), but just because physics isn't imposing it doesn't mean it doesn't exist.
If all you're doing is going from point A to point B in a line, then ignoring anything about top speeds (outside the speed of light without an FTL drive) is indeed fine and dandy. But in combat, especially fighter combat, imposing a top "safe" speed is entirely realistic. Using speeds listed in the book as a base would probably make sense, and those speeds may indicate that assumptions about fighters having powerful inertial dampening may be false.
BTW, the main Phase World book mentions that moving above certain high speeds gives a penalty to dodge and makes dogfighting impossible....which basically is what I'm saying.

As to inertial reduction sustems....
Is inertial reduction mentioned in any of the PW books? If not, hopefully it'll be touched in the fleets book. I dont have AU; does it have any details about inertial reduction, or just mentions what has it? And do any fighters use it, or just larger ships?
It being related to gravitic technology does make sense, but its entirely possible that you dont need contragrav tech. Robotech doesn't mention inertial dampening, but they do have gravitic technology: antigrav engines and artificial gravity. Thus, it makes sense they have inertial dampening, at least in the ships. As for fighters, I'd definately say no, though they'd certainly have G suits.
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Unread post by glitterboy2098 »

If speeds above a certain point restrict your ability to maneuver to the point where any simple turret A.I. can telegraph your course and shoot you down like child's play, and pulling combat maneuvers at, say, mach 15 (just throwing out numbers) causes you to black out, and doing so at, say, 20 causes you to hemorrhage internally and die, then for all intents and purposes there is a top combat speed. Maybe its imposed by your fighter (if you go too fast you cant maneuver quickly and become a sitting duck), maybe its imposed by your biology (too many Gs and you're a casualty without ever getting hit), but just because physics isn't imposing it doesn't mean it doesn't exist.


Mach 15 isn't even orbital velocity. and if you are at orbital velocity (20-33 mach), your cruising, and in freefall. no G-forces. if you alter course, you only experiance the force from the course change, which is gojng to be gradual because you can't bull extreme manuvers, orbital mechanics won't let you. this isn't dogfighting. it's rocketteering. if your in an equitorial orbit, and you want ot move to a polar orbit to close on a target, you position your ship the correct way and kick on your engines long enough to accellerate to the new orbit. your manuverbility is defined by how long it takes to reach that new orbit. low manuverbility = low thrust = more time to change orbit. high manuverbility = high thrust = less time to change orbits. you only experiance the backwards thrust of the engine, and you only thrust at levels safe for the crew.

BTW, the main Phase World book mentions that moving above certain high speeds gives a penalty to dodge and makes dogfighting impossible....which basically is what I'm saying.

and where did i state otherwise? all i am doing is moving said pointup to a new level.


and where did i say physics aren't imposing G-force limits? G-forces are pure Physics. i merely choose to leave such issues up to the GM, and not create a rules heavy system!
if you want that, go use Kitsune's rules and stop trolling.
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Unread post by Sgt Anjay »

Combat requires maneuvering. Maneuvering creates G forces. The faster you go while performing combat maneuvers, the more G forces you'll deal with. Since there's a limit to how many Gs a pilot can take, there's an upper limit to how fast a fighter can move and still fight.

Modern atmospheric fighters are physically capable of maneuvers extreme enough for human pilots to black out; space doesnt alleviate this, it makes it worse because not having to worry about lift, control surfaces, gravity, stalling, etc, you can easily pull maneuvers much more extreme than is possible in atmo. Maneuvers extreme enough to not just black you out, but seriously injure or kill. Add in more advanced propulsion methods, and it quickly becomes a matter of the fact that you'll build a fighter capable of all kinds of things it will never do because doing them will kill your pilot. Move at that kind of speed and either you'll be an easier target to track because you wont maneuver fast enough to avoid any incomming, or you'll kill yourself from G forces trying to maneuver.

Thats why I brought up the listed speeds in the books in my previous post. I say for simplicity's sake just take those as the top combat speed a fighter is capable of without physically harming the pilot. They may even be preprogrammed by the manufacturers into governor software, not allowing you to make certain maneuvers at certain speeds so as to avoid lawsuits (or irate military forces; I'd be more scare of the lawyers, myself).
Which, basically, means that all I'm saying is one can use the stats as written in the books when it comes to combat, while acknowledging that the craft can accelerate nigh unto forever when not in combat. Wow, rules heavy approach. :roll:
And by the way, proposing alternatives to a house rule is not trolling.
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Unread post by glitterboy2098 »

sigh. and where in the preceeding posts did i indicate otherwise?

your arguing on a point we both agree on. my point is that canon space velocities are absurdly slow.
in regards to 'top combat speeds' none of the listed 'speeds' are even capable of reaching space, much less manuvering in it. so an improvement was warranted.

since it was silly to increase speed while still violating the laws of conservation of inertia, i stuck them in.

yes manuvering is still limited by G-forces. but remember, you have a lot more space to manuver in, so not being able to pull pin point turns isn't an issue. plus, at the velocities involved and the distances involved, time lag between firing and impact makes combat no more ineffective or effective than normal. plus you have to add in issues with targeting and tracking, attack timing, ect.

this site has everything you could need to do a decent space battle. it's a hard science veiw, but it should help a lot.
This page has targeting info
Strategy and tactics, including the use of manuver in combat.


if you don't like it, don't use it.
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