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#1 Amaimon

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Posted 30 January 2014 - 03:51 AM

So I was doing some calculations about intra system flight.

 

A ship with speed of 10 VU, flies about 200,00 km/h which means a distance from earth to moon would be covered within 2 hours. With some orders its possible to do it in one hour. Eldar ships could pull it off in half hour.

 

This is of course battle speed, with manouvers etc. In Stars of Iniquity it says, that travel to the edges of solar system takes about 2 week for an avarage system. As a edge, for safe jump I estimated about 100 AU, which means far beyond kuipers belt. To get there in two weeks a ship would have to have speed of 0,041 c, which is about 12,400 km/s. With this speed the distance to the moon would be covered in 30s.

 

What this means.

 

Do ships really have to fly for two weeks to make a safe warp transition? Why? Warp is warp, real space gravity, shouldnt affect this?

 

ANY relief fleet would take about a month to get whenever they need too. Lets say a fleet that is only a week of warp travel away, takes two weeks to get to jump point, and then another two to get to the planet. So 5 weeks.

 

In novels and games everything takes much less time, otherwise it would be reaally boring. I know it makes sense, but that prevents keeping action on high pace. Heroic last minute rescues, etc.Thats also why, I'm not a fan of one strategic turn lasting 30 minutes of real time.

 

"Fire the guns! And now its time for a cup of tea. They won't fire on us for the next half hour, so how about a quick ping-pong match?"

Also not a fan of hundreds of people turning cogs and moving gigantic shells. Its just so stupid, and pointless. In grimm darkness of far future their is only boredom of space, and huge inefficency.

 

 



#2 Amazing Larry

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Posted 30 January 2014 - 04:48 AM

You're not reading between the lines, the way it's presented in the RT material synches up really well with most established lore. It's been years since I read the Guard codex but one thing I do remember is the concept that it takes the Guard a year or two to start piling on but once they are piling on woe betide any non-swarm army.

 

As for warp jump points and materium travel times do a search it's been discussed into the ground, but the gist always remains the same in that hauling in or out of system from the playing safe jump points takes one to two weeks at a minimum depending on your engines and hull. As for how it works who knows, the scientific principles behind warp travel haven't been understood since the dark age of technology. For whatever reason large gravity wells make it dangerous or impossible to transition in and out of the warp depending on a wide number of factors, so you have to haul out about Pluto distance if you wanna do it without risking your ass.

 

Now regarding Starship Combat turns it's not as if each ship fires off a volley from each gun every thirty minutes and calls it good and a "macrocannon" isn't even a single gun but rather a cluster of guns on a turret. It's an abstraction of a large number shells  being fired by that gun cluster over a thirty minute period and an abstraction of how many hit home in that period. 40k's conception of gunnery is very rooted in WW2 among other things and during WW2 an anti-air gun would fire about two thousand rounds for every one that actually struck an aircraft.

 

Now considering the size of a macroshell and a starship the odds aren't anywhere near that long but the majority of shells still just go flying off into space.


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#3 Marwynn

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Posted 30 January 2014 - 09:11 AM

Keep in mind that the speed is actually acceleration. If 1 VU = 20,000 km and a Speed of 1 = 20,000 kph, then it actually takes less than an hour to reach the moon from Earth with a Speed of 10. 

 

First 30 minutes is flying at 200,000 kph. The next turn of 30 minutes is then travelling at 200,000 kph and accelerating on top of that. Now this is using combat speed, where the ship would be required to manuever and actually decelerate. Which is a good reason why in combat, our voidships don't just zip by each other with relative velocities at several hundreds of thousands of kph and whatnot.

 

The game says as much when it shows the ships' accelerations. Page 312 says that they reach approximately 0.01c in their travel time. They don't use their full acceleration while they're still near the system's heart, risk of collisions are too great. Then once they make it to their destination they decelerate from their 0.01c speed. So gutsier captains (or foolish ones) will push the deceleration to the last possible moments and arrive quickly.

 

Novels are inconsistent with this. Games are horribly, horribly wrong about it. I play the Dawn of War 2 games on and off and they just zip around the warp like it's nothing... just one of the many problems I have with it. 

 

Secondly, as Amazing Larry pointed out, you're not firing one shell per 30 minutes. Unless it's a Nova Cannon or a Torpedo Tube, you're firing multiple times with macrobatteries. Lances too could fire multiple times. 


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#4 Amaimon

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Posted 30 January 2014 - 09:23 AM

Travelling to a planet in the inner solar system, would be a week of acceleration and week of deceleration. 

 

Also its a good way for players to shine. If they want to get somewhere realy quickly, they can pass some navigation (stellar) tests to use the gravity of the planets to help them brake, without turning the crew into gello. 

 

I know that firing macrobatteries (i think batteries is the key word here) is firing multiple shells. But looking at how are they loaded really makes you wander if they are really capable of firing more than twice or thrice in half hour. Macrocannon_Schematic.png


Edited by Amaimon, 30 January 2014 - 09:25 AM.

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#5 Roy Stone

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Posted 30 January 2014 - 09:42 AM

I feel sorry for any group who can't find anything to occupy their characters for 5 weeks.

 

Leaving a system might well be boring. But could there be cause to have a small adventure during those two weeks?

 

(1) Some mutant rats gnawing on cables in Gellar Field control. Explorator needs to make repairs while the Arch-Militant leads an assault force to exterminate the vermin.

(2) Perhaps some human or alien raiders/pirates are loitering close to the edges of the system. Whether part of an ongoing war, or just out for themselves, they harass any ship traffic that passes by them and today that traffic is you.

(3) Attempting to flee Imperium "justice", a criminal or rogue psyker seeks to stowaway on board your ship. Unfortunately, it isn't long before the individual(s) cause problems and the hunt for them is on.

 

I favour the Rogue Psyker as that will branch out into a mini-campaign in it's own right. Daemons, Enslavers and Psychneuein might burst forth from such a Psyker.

 

What about a week in the warp?

 

(1) We have a table for things that go bump in the warp. But why not have a daemon appear on board and require hunting. (2) Perhaps being in the warp causes some madness in the crew and they need shooting.

(3) Some among the crew are tainted by Chaos and now is the time to rise up and take, or doom, the ship.

 

These are just what come to mind, but something as simple as a mutiny could happen as rumour spreads as to their destination. Naturally, a continuation of the Rogue Psyker idea I had earlier could mean battling Enslavers or Psychneuein.

 

Two weeks to destination in system?

 

Human or alien raiders/pirates again. Indeed, if the system is being invaded, these could be patrols or hunting parties. Perhaps an Imperial system ship or two, incapable of warp travel, has been being chased and upon your arrival are seeking protection.

 

You could even play out the "boring" parts of the ship travel playing the chase.

 

 

The only limit to your enjoyment is your imagination.


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#6 venkelos

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Posted 30 January 2014 - 12:59 PM

Now regarding Starship Combat turns it's not as if each ship fires off a volley from each gun every thirty minutes and calls it good and a "macrocannon" isn't even a single gun but rather a cluster of guns on a turret. It's an abstraction of a large number shells  being fired by that gun cluster over a thirty minute period and an abstraction of how many hit home in that period. 40k's conception of gunnery is very rooted in WW2 among other things and during WW2 an anti-air gun would fire about two thousand rounds for every one that actually struck an aircraft.

And then I see the Mass Effect 2 Sergeant chewing out his fools, reminding them that they are ruining someone's day, somewhere, at some time. Thank you. ;)



#7 Tristonic

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Posted 30 January 2014 - 03:42 PM

Also, are we forgetting that the Warp is a parallel dimension with the Materium? What's in the warp is a mirror of what's in real space, which is why you go to the 'safe' jump points. Well beyond the gravity of any planet.

 

http://wh40k.lexican...um#.UurHJbT3QxE



#8 Fortinbras

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Posted 30 January 2014 - 10:01 PM

I feel sorry for any group who can't find anything to occupy their characters for 5 weeks.

 

Leaving a system might well be boring. But could there be cause to have a small adventure during those two weeks?

 

 

Because session time is limited and we don't want to distract ourselves from the main plot with that kind of thing?   I generally ignore the official word on ship combat time and system transitions.  It's very hard to keep cinematic tension if it's two weeks from jumping into eldritch-horror system to getting to eldritch-horror planet of the damned or 30 minutes for time-to-target.   Pacing is just as important in a tabletop RPG as it is in a video game or a movie.

 

Auspex Officer: "Captain! Incoming enemy volley!" 

 

Captain: "Brace for impact!"  

 

(30 minutes later)

 

Captain: ........

 

Captain: ........

 

Captain: .........

 

(shells strike ship) 


Edited by Fortinbras, 30 January 2014 - 10:03 PM.

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#9 Alasseo

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Posted 30 January 2014 - 10:36 PM

Keep in mind that the speed is actually acceleration. If 1 VU = 20,000 km and a Speed of 1 = 20,000 kph, then it actually takes less than an hour to reach the moon from Earth with a Speed of 10. 
 
First 30 minutes is flying at 200,000 kph. The next turn of 30 minutes is then travelling at 200,000 kph and accelerating on top of that. Now this is using combat speed, where the ship would be required to manuever and actually decelerate. Which is a good reason why in combat, our voidships don't just zip by each other with relative velocities at several hundreds of thousands of kph and whatnot.
 
The game says as much when it shows the ships' accelerations. Page 312 says that they reach approximately 0.01c in their travel time. They don't use their full acceleration while they're still near the system's heart, risk of collisions are too great. Then once they make it to their destination they decelerate from their 0.01c speed. So gutsier captains (or foolish ones) will push the deceleration to the last possible moments and arrive quickly.
 
Novels are inconsistent with this. Games are horribly, horribly wrong about it. I play the Dawn of War 2 games on and off and they just zip around the warp like it's nothing... just one of the many problems I have with it. 
 
Secondly, as Amazing Larry pointed out, you're not firing one shell per 30 minutes. Unless it's a Nova Cannon or a Torpedo Tube, you're firing multiple times with macrobatteries. Lances too could fire multiple times.

Indeed, the 0.01c is merely a safe economical "maximum" used for travel out to a jump point with no major hurry. There's traffic and debris aplenty (relatively speaking, of course. Space is really big, and very empty) in the inner system, and the more stress you put on the engine (even without Flank Speed/AAF type actions), the more maintenance needs doing (and so the more it'll cost).
 
In battle, or in emergencies, it is entirely possible that ships will exceed that (iirc several ships during the Heresy are noted as maneuvering at ~0.4c). The practical issue is, of course, that relativistic effects make aiming at something while travelling that fast... problematic. As it stands, IN gunners get treated really lightly when it comes to regulations because their job is so hard and stressful*. Asking them to hit targets at that speed? Not going to happen.
Quite aside from the relativistic effects of the ship's own velocity (which will be spectacular, but distracting. Just ask Carl Sagan), the enemy ship is also going to be moving, and may accelerate in one or more of 6 possible directions to throw off your aim (speed up, slow down, turn towards, turn away, "climb" or "dive"), and you have no way of knowing exactly what it is going to do until potentially several minutes after it has done so, given potential engagement ranges**. And in the meantime, your shots may still not have reached it.
Moving far slower than you theoretically could, therefore, makes a lot of sense for anyone who wants to fight (at least, if they want a chance of hitting something), and for someone who isn't running for their life and has to pay for engine maintenance/fuel.

If you want a feel for what space combat at these sort of ranges should be like, if done realistically, I heartily recommend the Lost Fleet series by John G Hemry (writing as Jack Campbell). The best way to describe the effect on the crews is boring but stressful
 
*At least according to Battlefleet Gothic. They have a tiny interval in which their guns are going to fire so they actually stand a chance of hitting the target, which of course, will obscure maybe a second of arc, if that, despite being several kilometres long. This interval is measured in fractions of a second, so they need to be on alert with tip-top reflexes, and they may be waiting for literally hours before it comes. It is therefore relatively common to issue them with stimulant cocktails so they can keep their edge. Nervous breakdowns are far from unknown as a result.
**Ok, that may be an exaggeration- this thread gives us an upper limit on range of just under a light-second, although it predates the release of most supplements, which have included some longer-ranged weapons.

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#10 Fortinbras

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Posted 30 January 2014 - 10:53 PM

 

Indeed, the 0.01c is merely a safe economical "maximum" used for travel out to a jump point with no major hurry. There's traffic and debris aplenty (relatively speaking, of course. Space is really big, and very empty) in the inner system, and the more stress you put on the engine (even without Flank Speed/AAF type actions), the more maintenance needs doing (and so the more it'll cost).
 
In battle, or in emergencies, it is entirely possible that ships will exceed that (iirc several ships during the Heresy are noted as maneuvering at ~0.4c). The practical issue is, of course, that relativistic effects make aiming at something while travelling that fast... problematic. As it 

 

 

0.4c has a negligible time dilation effect.  It doesn't become dramatically noticeable until about 0.6c or so.

 

Interestingly enough, a lot of sci-fi recently that's tried to be more "hard" and returned to things like characters sunk into gravity couches as they pull incredible G's for extended amounts of time often have ships engaging in combat at anywhere from 0.4-0.6c.    I think 0.4c is a fair speed for a ship to traverse a solar system at in the grim darkness of the 41st Millennium, which, doing a bit of math here, would take a ship 33 hours to traverse from Earth to the heliopause of our solar system.   Hardly two weeks.

 

Also as for hundreds of men loading cannons, this isn't just barbaric stupidity, but an Imperial distrust of automation to get the job done.   When your power systems and datacables have been shredded into swiss cheese by Ork Gunz, you need someone on the gun deck who can get the job done.  

 

That being said, your first trip should be to Zayth to negotiate for their handy auto-loading tech. 


Edited by Fortinbras, 30 January 2014 - 11:10 PM.


#11 Tenebrae

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Posted 31 January 2014 - 01:08 AM

0.4c has a negligible time dilation effect.  It doesn't become dramatically noticeable until about 0.6c or so.

This has been covered elsewhere on this forum.
 
And as for the negligible time dilation effect I should point out that we use the full relativistic calculations for anything above 0.01c. This is because otherwise deviations become too large to ignore.

Eg. if you want to hit something the size of a planet.

At your suggested 0.6c, I probably wouldn't even bother talking about speed/velocity, because it will be largely senseless, I would probably be discussing things in terms of gamma instead.



#12 Amaimon

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Posted 31 January 2014 - 04:06 AM

Also it would be nice, if the ships could change the stern position during combat.

 

Eg ship accelerates to speed of 10, then uses manuvering thrusters to change position of the stern by 180, and then fire upon the pursuers. Or fly with port/starboard first, like in homeworld 2

 

hw2-destroyers02.jpg



#13 Radwraith

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Posted 31 January 2014 - 04:55 AM

You are all assuming a linear flight. In Narrative time the RAW actually suggest that the ships use continuous acceleration/deceleration to reach their target point in space. This combined with a parbolic decelerating turn to bring the ship into orbital sync with it's target planet means that the ship will still approach it's intended destination head on. This is why stellar navigation is not just "point and shoot" from the navigators perspective! While it would certainly be possible to calculate all this manually, from a gaming perspective THAT would be painful for most players! Easier for both player and Gm to say; "You travel for two weeks in system. the transit is uneventful and you now see planet Eldritch horror in your forward viewports. Captain, what are your orders?" If the Gm wants to throw encounters at the party on the way in that's certainly his right but otherwise, Narrative time is intentionally flexible!  


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#14 Alasseo

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Posted 31 January 2014 - 05:22 AM

You are all assuming a linear flight. In Narrative time the RAW actually suggest that the ships use continuous acceleration/deceleration to reach their target point in space. This combined with a parbolic decelerating turn to bring the ship into orbital sync with it's target planet means that the ship will still approach it's intended destination head on. This is why stellar navigation is not just "point and shoot" from the navigators perspective! While it would certainly be possible to calculate all this manually, from a gaming perspective THAT would be painful for most players! Easier for both player and Gm to say; "You travel for two weeks in system. the transit is uneventful and you now see planet Eldritch horror in your forward viewports. Captain, what are your orders?" If the Gm wants to throw encounters at the party on the way in that's certainly his right but otherwise, Narrative time is intentionally flexible!

As it happens, I wasn't, but I grant that I didn't say anything to suggest otherwise. Also- I agree completely. If you've ever tried playing Advanced Vector: Tactical, or the Saganami Island Tactical Simulator, you know that manually working out course corrections and vector changes in 3 dimensions (let alone the firing solutions) is a massive pain. Hell, the same has been applied to Battlefleet Gothic (which is far simpler than the above examples, and in many ways simpler than the starship combat system of Rogue Trader, although it is also suited to a larger scale).

I should also note that the 0.4c (or whatever) is or could be the velocity of your ship. The enemy vessel is also moving, and may well be moving as fast, or faster than you, so your gunners are trying to hit something a mere 1-5km long, at distances of tens of thousands of kilometers, with a relative velocity of (to maintain the example) up to 0.8c (I think. Relativity gives me a headache, and I have yet to have caffeine this morning).
Even if your batteries aren't firing more than once or twice per gun every 30 min or so, they're not just going to be twiddling their thumbs in the meantime. They're going to be reloading, while waiting for the gunnery officers to sweat through the math and give them another firing solution, for the senior officers (Master of Ordnance, say, or even the Captain) to check the various solutions given provided and pick one, and then waiting for the correct moment to fire. There's plenty of stuff to be done, and plenty of stress and suspense... all of which can be harmlessly glossed over for the sake of pacing and gameplay.

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#15 Tenebrae

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Posted 31 January 2014 - 08:26 AM

*sigh* I feel ignored.


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#16 Roy Stone

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Posted 31 January 2014 - 01:22 PM

 

I feel sorry for any group who can't find anything to occupy their characters for 5 weeks.

 

Leaving a system might well be boring. But could there be cause to have a small adventure during those two weeks?

 

 

Because session time is limited and we don't want to distract ourselves from the main plot with that kind of thing?   I generally ignore the official word on ship combat time and system transitions.  It's very hard to keep cinematic tension if it's two weeks from jumping into eldritch-horror system to getting to eldritch-horror planet of the damned or 30 minutes for time-to-target.   Pacing is just as important in a tabletop RPG as it is in a video game or a movie.

 

Auspex Officer: "Captain! Incoming enemy volley!" 

 

Captain: "Brace for impact!"  

 

(30 minutes later)

 

Captain: ........

 

Captain: ........

 

Captain: .........

 

(shells strike ship) 

 

 

I tend to just do the whole movie thing if I don't want any distractions or diversions.

 

"The Imperial ship leaves system A....5 weeks later the ship emerges from the hellish torment of the warp in system B, raised shields and readied for war....."

 

5 weeks in one sentence.

 

I do agree with your point of view. It can clutter things up too much. Not everyone shares my fun of Main Plot and Sub Plots. The paper work alone can be daunting.

 

Hello Tenebrae


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#17 Amaimon

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Posted 31 January 2014 - 01:39 PM

@Tenebrae - I've read all those other threads. The calculations there were awesome, I'm gonna use them extensively. 

 

From the works of 

wolph42

 

Assuming half time accelerating, and other half decelerating.

Time [days] = SQRT(8.2 * distance [AU] / acceleration [g])

 

or with no brakes. 

 

[days] = SQRT(4.1[AU]/[g])

 

 

Assuming 40 AU is the distance to exit point. 

G (DAYS, both for exit and entry)

 

g (Days)
1 (13)
1,5 (10,5)
2 (9)
2,5 (8)
3 (7,5)
4 (6,5)
5 (5,5)
6 (5)

 

 

ALSO JUMPING INSIDE SOLAR SYSTEM

In follow up to this post:

It's unlikely that your players ever will take the chance, but ORKS just might do this. So here a suggestion of the percentile mishap (= BOOM)

Assumptions:

- Warp exit/entry at edge: change of mishap 0% (concerning the gravity well)
- Warp exit/entry close to the star: chance of mishap 50% (again: concerning the gravity well). Initially I was thinking 100% but as habital planets are typically 1 AU away in a typically 40 AU solar system would mean that jumping close to the habital planet is about 100% chance on mishap. That with the fact that mishap = warpdrive explodes, in other words: end of story for the ship!! AND the reference earlier mentioned of the ork fleet jumping in on a star fleet in orbit, would have meant the instant decimation of the entire fleet. Hence: 50% chance on blow-up.

The formula to calculate this is very simple:

Chance on mishap = (7*DFE/SR)^2 %

here is:

SR = Solar system Radius (e.g. 30 AU, solar system of Terra)

DFE = distance from edge of the solar system where you jump in. E.g. with an with an SR=30, 0 is the edge and 30 is inside the sun. Entry at halfway = 15 AU:

Mishap = (7*15/30)^2 = 12%.

If you like to keep things simple and assume EVERY solar system of size 50AU then the formula becomes really simple:

Chance on Mishap = DFE^2 / 50 %

To resolve simply throw a 1d100 if you roll UNDER the set score: BOOM

Some chances (assuming SR = 50)

Jumping in at:
Distance from edge - %

0 (jump at the edge) - 0%
6 - 1%
10 - 2%
20 - 8%
30 - 18%
40 - 32%
49 (jumping close to a habital planet which are typically at 1 to 3 AU away from its sun) - 48%
50 - 50%

 

ALSO JUMPING INTO LAGRANGIAN POINTS

 

mm interesting notion… I guess that in that case L1 to L3 are right out as they are unstable and too small to ever make that jump (in addition 1 and 2 are REALLY close to the planet), which leaves L4 and 5, which are stable and quite a bit larger then 1,2 and 3. If you would jump there then you would be at 1AU distance from the planet. L4 and 5 are actually pretty big, about 1AU length and half that in width so its not THAT hard. What makes it hard in general to find the right spot at all is the fact of the time distortion in the warp. In order to jump right next to a planet or in a lagrange point you need to know the time (as that decides the position of the planet and LP in regard of its star).

So basically you want to jump at a distance of 1AU from the star without much error, lets say max 10% so within 0.9 to 1.1 AU AND you need to know the exit time. Both these rolls are part of the 5 navigation steps.

First you need to know the time, now the LP are pretty big so there's always a 30% chance that you jump into one. And I would rule that if you jump in from farther then from the edge of the solar system as beyond that its really completely random at what exact time you jump in. Should you jump first to the edge and then from the edge to the LP then I would rule a very hard Navigation Warp test (-30) for the correct estimate, however since there is a 30% chance that you get it right anyway I would simply rule a Navigation Warp Test (+0). Every degree of fail increases the difficulty of the 'leaving the warp' with one step, more then 3 DoF means your NOT jumping in the LP.

'Charting course' is negligible (again assuming jumping from edge) so ordinary warp

'steering vessel' will again influence the time and space exit which are vital so again very hard test (-30) navigation warp and again 3 DOF means NOT jumping in the LP and every DoF increases the difficulty with one step on leaving the warp.

When that's done you need to roll 'leaving the warp test' which is usually at -20, this time modified with the DoF of the other rolls.

Should you actually succeed this test then this would half the chance of BOOM to 24% lowering it further with 1% for every degree of success. Fail would mean you arrive at roughly 1AU from the sun: 48%. Should you fail this warp with 6+ DoF then you jump straight into the sun.


Edited by Amaimon, 31 January 2014 - 01:45 PM.


#18 Tenebrae

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Posted 31 January 2014 - 02:51 PM

Thanks people, I'm all touched here :rolleyes:

 

but the point was that the subject pretty much has been discussed before and probably will be again.

Please use a few seconds to dive for this sort of thing, maybe those old threads have your answers :)


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#19 Radwraith

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Posted 31 January 2014 - 03:47 PM

@Tenebrae - I've read all those other threads. The calculations there were awesome, I'm gonna use them extensively. 

 

From the works of 

wolph42

 

Assuming half time accelerating, and other half decelerating.

Time [days] = SQRT(8.2 * distance [AU] / acceleration [g])

 

or with no brakes. 

 

[days] = SQRT(4.1[AU]/[g])

 

 

Assuming 40 AU is the distance to exit point. 

G (DAYS, both for exit and entry)

 

g (Days)
1 (13)
1,5 (10,5)
2 (9)
2,5 (8)
3 (7,5)
4 (6,5)
5 (5,5)
6 (5)

 

 

ALSO JUMPING INSIDE SOLAR SYSTEM

In follow up to this post:

It's unlikely that your players ever will take the chance, but ORKS just might do this. So here a suggestion of the percentile mishap (= BOOM)

Assumptions:

- Warp exit/entry at edge: change of mishap 0% (concerning the gravity well)
- Warp exit/entry close to the star: chance of mishap 50% (again: concerning the gravity well). Initially I was thinking 100% but as habital planets are typically 1 AU away in a typically 40 AU solar system would mean that jumping close to the habital planet is about 100% chance on mishap. That with the fact that mishap = warpdrive explodes, in other words: end of story for the ship!! AND the reference earlier mentioned of the ork fleet jumping in on a star fleet in orbit, would have meant the instant decimation of the entire fleet. Hence: 50% chance on blow-up.

The formula to calculate this is very simple:

Chance on mishap = (7*DFE/SR)^2 %

here is:

SR = Solar system Radius (e.g. 30 AU, solar system of Terra)

DFE = distance from edge of the solar system where you jump in. E.g. with an with an SR=30, 0 is the edge and 30 is inside the sun. Entry at halfway = 15 AU:

Mishap = (7*15/30)^2 = 12%.

If you like to keep things simple and assume EVERY solar system of size 50AU then the formula becomes really simple:

Chance on Mishap = DFE^2 / 50 %

To resolve simply throw a 1d100 if you roll UNDER the set score: BOOM

Some chances (assuming SR = 50)

Jumping in at:
Distance from edge - %

0 (jump at the edge) - 0%
6 - 1%
10 - 2%
20 - 8%
30 - 18%
40 - 32%
49 (jumping close to a habital planet which are typically at 1 to 3 AU away from its sun) - 48%
50 - 50%

 

ALSO JUMPING INTO LAGRANGIAN POINTS

 

mm interesting notion… I guess that in that case L1 to L3 are right out as they are unstable and too small to ever make that jump (in addition 1 and 2 are REALLY close to the planet), which leaves L4 and 5, which are stable and quite a bit larger then 1,2 and 3. If you would jump there then you would be at 1AU distance from the planet. L4 and 5 are actually pretty big, about 1AU length and half that in width so its not THAT hard. What makes it hard in general to find the right spot at all is the fact of the time distortion in the warp. In order to jump right next to a planet or in a lagrange point you need to know the time (as that decides the position of the planet and LP in regard of its star).

So basically you want to jump at a distance of 1AU from the star without much error, lets say max 10% so within 0.9 to 1.1 AU AND you need to know the exit time. Both these rolls are part of the 5 navigation steps.

First you need to know the time, now the LP are pretty big so there's always a 30% chance that you jump into one. And I would rule that if you jump in from farther then from the edge of the solar system as beyond that its really completely random at what exact time you jump in. Should you jump first to the edge and then from the edge to the LP then I would rule a very hard Navigation Warp test (-30) for the correct estimate, however since there is a 30% chance that you get it right anyway I would simply rule a Navigation Warp Test (+0). Every degree of fail increases the difficulty of the 'leaving the warp' with one step, more then 3 DoF means your NOT jumping in the LP.

'Charting course' is negligible (again assuming jumping from edge) so ordinary warp

'steering vessel' will again influence the time and space exit which are vital so again very hard test (-30) navigation warp and again 3 DOF means NOT jumping in the LP and every DoF increases the difficulty with one step on leaving the warp.

When that's done you need to roll 'leaving the warp test' which is usually at -20, this time modified with the DoF of the other rolls.

Should you actually succeed this test then this would half the chance of BOOM to 24% lowering it further with 1% for every degree of success. Fail would mean you arrive at roughly 1AU from the sun: 48%. Should you fail this warp with 6+ DoF then you jump straight into the sun.

This is all good information and a good 'scientific' application! My take on it has been to apply a more fluffy approach as follows: Most Starships will, for the sake of safety enter a system at a "safe" distance in the outer region of said system however, certain situations may require a more risky re-entry! The most common (Although hardly 'common') reason is when responding to a distress call. When a ship in the warp responds to a distress call they are responding to an astropathic transmission. This effectively sets up a beacon that a Skilled navigator can "Lock-on" to and thus bring his ship out of the warp MUCH closer to the transmission source (Perhaps a hard -20 Psyniscience test.) If the Navigator is successful at locating said beacon he plots his re-entry normally into realspace. Because the ship is entering realspace in a Gravity riptide. (RT. pg. 227) There is no avoiding this but the ship's Helmsman may choose to "Shoot the rapids" as stated in the same section. If this happens during combat the vessel enters the map at twice it's normal combat speed and may not turn until it has reduced speed to normal (Normally 1/2 of the vehicles thrust value per turn but special maneuvers can affect this). The resulting warp rift may also have similar consequences for the ships within 5 VU of the emergence point. The rift is temporary and only lasts one (Starship) turn.

 

This method explains the classic "Blasting in in the nick of time" scenario. If you really want to get all warp cheesy I would suggest that the emotion of a few thousand crewmembers in distress creates a time dilation within the warp that often contributes to this "Nick of time" effect! ;)



#20 Roy Stone

Roy Stone

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Posted 31 January 2014 - 03:47 PM

Thanks people, I'm all touched here :rolleyes:

 

but the point was that the subject pretty much has been discussed before and probably will be again.

Please use a few seconds to dive for this sort of thing, maybe those old threads have your answers :)

 

Please forgive this lazy newbie. I hang my head in shame  :(

 

See you in a few weeks when someone else brings up the topic  :)






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