Jump accuracy in ANY Traveller System

[Hal]

Hello Folks,
In looking at the rules in CT, MT, T3 (Traveller: The New Era), T4, GT, and MgT (don't know about T20 as I never purchased the D&D based product) - only ONE of the game systems mentioned above actually attempted to do something with the Navigator skill (or Astrogation skill).

What is maddening about this is that MgT alludes to the potential for accuracy or lack of it, causing a ship to either have a either a Mis-jump or an inaccurate jump, or having a jump that is accurate. Problem is, I can't find the rules in MgT main rule book that say what specifically happens (ie how far off the inaccurate jump is). The Example of play on page 3 gives a tantalizing hint of what is involved for an inaccurate jump, but nothing is spelled out later on (table or otherwise that I could see).

T5 has an interesting bit on how accurate (or inaccurate) a jump might be. On an inaccurate jump the distance is equal to flux plus 12 on the Space Range table. As such, an inaccurate jump could range between S7 on up to S17. S17 is REALLY far out (Pun not intended!).

So, anyone got a hint on what/where I can find those inaccurate jump rules specs?

The reason I'm asking is because in my traveller universe (not standard!), precipitating out of Jump space due to bumping into a 100 diameter limit for a star or planet causes minor damage (I'm using GURPS TRAVELLER if that helps).

The way I'm going to try and work it (Similar to how MgT does it) is that a failed roll by 2 or more, results in a misjump, while a miss by 1 means an extreme (outer orbits) style inaccurate jump, and a success up to +3 means an inaccurate jump measured in smaller units.

As I look at what S17 is in actual distance, I was dismayed to discover that it had a range band designation of about 1230 AU's or seven light days from the intended location - making for a LONG travel time to the target world.

So, I'd like to try and find ways to make this a little more interesting for my player and not hose him down - but also give meaning to the skill of Astrogation where it means something and has impact in game play.

Thoughts?

 

[Spinward Scout]

MegaTraveller Imperial Encyclopedia has Jump Mishaps on pg. 93. It could be used for what you're looking for.

MgT has some rules on pg. 141.

 

[aramis]

Note that inherent accuracy is ±1000km per parsec in most editions.

 

[Whipsnade]

CT is going to be tough for you to pin down, Hal. Everything is scattered through different books, supplements, and articles, all of which don't exactly jibe with each other.

There are changes in misjump rolls between the 1977 and 1981 versions but both versions of [LBB:2 agree that jump takes a week. Not so many hours or day, a "week". HG2 gives us a range of 150 to 175 hours (which is not quite the "168 hours +/- 10%" we so often quote here.) HG2 also baldly states vectors are retained through jump.

Mr. Miller's jump space article in JTAS #24 is probably the most "concentrated" source of jump accuracy and misjump effects. In that article, the 168 hours +/- 10% is flatly stated. Jump is said as having an accuracy of "... less than one part per ten billion." and arrival point predicted to "... perhaps within 3,000 kilometers..." for jumps of one parsec while bad plots and poorly tuned drives can increase jump error by "... a factor of ten." Jump masking and jump shadows are also implied.

While the article has a section on misjumps, it's more of a set of vague suggestions for the referee than concrete numbers.

 

[Hal]

MegaTraveller Imperial Encyclopedia has Jump Mishaps on pg. 93. It could be used for what you're looking for.

MgT has some rules on pg. 141.

Thanks for the reminder about MegaTraveller. Using the information cited in there, the inaccurate jump could result in the ship being between 8 to 48 light hours away from the intended point of jump space exit. While that is a bit more definitive, it is still a NASTY penalty for a ship that has to transit normal space to reach their main world destination.

When I read through the rules in MgT, page 3 was the example, while page 141 had SOME of the rules involved, but not table or formula that one could look at and say "Succeed by less than 8, but more than 0 - and you end up at X distance away from your planned exit point".

In all, my goal here is to find an alternative to Jump Masking as to why ships end up having to transit through normal space to reach their main world destination.

Why do I want this?

Jump Masking leaves a raw taste in my mouth. I see the "need" to force ships to transit normal space to enhance the time it is vulnerable to space activities (such as piracy etc), but if that can be achieved by using an alternative "Navigation roll" methodology, then I'm happy.

Eventually? I think I'm going to realize a long standing dream of mine:

Detail the star system of Adibicci, Ianic, Derchon, and Lunion for a nval campaign where one player commands a Destroyer class ship, one player is in charge of a single pirate ship, and using GURPS rules for sensor ranges etc - have the pirates try to avoid being caught (usually by not operating in the same system as the Destroyer!) and not being so successful that the area is declared to be in need of beefed up patrols (where up to four more destroyers can be deployed - not to mention destroyer escorts!)

As it is? Whipsnade played a big part in my not turning my back on Traveller Forever (And I'm glad I got the chance to meet him face to face that one day - someday, I'd like to meet up with him again!)

Long story short, the more I can detail certain things, the more I can put a dream into action: Using Fantasy Grounds 2 - run a campaign of Pirates Versus Navy. Then hit the naval player with various issues such as some crew members reaching a time where they are near Voluntary Separation from service and need to be returned back to the Naval base at Lunion in preparation for discharge. Then there is that pesky requirement for yearly maintenance, etc.

In the end? I'd like to try my hand at that scenario that has been in my mind since 2004.

Who knows?

 

[Hal]

CT is going to be tough for you to pin down, Hal. Everything is scattered through different books, supplements, and articles, all of which don't exactly jibe with each other.

There are changes in misjump rolls between the 1977 and 1981 versions but both versions of [LBB:2 agree that jump takes a week. Not so many hours or day, a "week". HG2 gives us a range of 150 to 175 hours (which is not quite the "168 hours +/- 10%" we so often quote here.) HG2 also baldly states vectors are retained through jump.

Mr. Miller's jump space article in JTAS #24 is probably the most "concentrated" source of jump accuracy and misjump effects. In that article, the 168 hours +/- 10% is flatly stated. Jump is said as having an accuracy of "... less than one part per ten billion." and arrival point predicted to "... perhaps within 3,000 kilometers..." for jumps of one parsec while bad plots and poorly tuned drives can increase jump error by "... a factor of ten." Jump masking and jump shadows are also implied.

While the article has a section on misjumps, it's more of a set of vague suggestions for the referee than concrete numbers.

Yup. That's why I was getting to the point of minor frustration. With all the systems done since 1977, you'd think we would have something definitive. Mongoose Traveller was the first "hint" that there might be something reasonable out there, but its rules were essentially:

Roll an effect of zero or less, Misjump
Roll an effect of 8 plus, jump exit where desired
that leaves an effect between 1 and 7 inclusive, where the ship entered into an inaccurate jump.

In GURPS, this might be something like "Failed skill roll results in no jump, crit failure results in a misjump.

Successful roll less than by 3 (ie a skill of 12 requires a roll of a 9 or less on 3 six sided dice) - inaccurate jump
Success by 3+ is a normal jump with minor errors in distance (1d6 light seonds maybe?) while a success by 5+ means dead on nagivation.

I want to be able to simulate the longer "in transit" times as given in Jump Masking rules, without using Jump Masking rules!

by the by - email me hal AT roadrunner and the com with that period before com. I'd like to chat with you again.

It has been a while since I last saw you and left you a copy of THE MILLENNIAL PROJECT. A lot of time has passed, and I still smile remembering the fun I had trying to find your place with all those trees around it!

Hope to hear from you soon.

Hal

 

[Hal]

Note that inherent accuracy is ±1000km per parsec in most editions.

True enough. Most editions being:

CT
T4

I had forgotten the MT rule about 1d6*8 light seconds (I never really used MT as a referee and have never played it, I generally used MT for source material fleshing out the Traveller history.

T5 has that rule I alluded to regarding 1230 AU's at its most distant range (a change from 1,000 kilometers for sure!)

MgT had that hint of a rule, but not fleshed out.

TNE I don't think had a change to it, so that makes it part of the team that has the 1,000 kilometer rule. With the FF&S rules for ship building and ship movement, it probably wouldn't have survived a 60 parsec chase to the main world due to an inaccurate jump.

T20 I have no knowledge of, so I can't say what it does or doesn't have, and I will never likely pick up HERO TRAVELLER <shrug>

Now what remains for me to do is come up with something that can approximate the jump masking transit times as "inaccurate jump results" and I'll be happy.

Thanks for your input!

 

[Marchand]

There are rules for jump accuracy in CT Beltstrike, Folder 1 "Lodes of Adventure":

"A mistake in navigation could place the shlp further from the
desired location (but never closer in). Commercial ships rarely make
such mistakes, but they may occur with private vessels. Throw 10 +
for a slip in computations to cause a mistake in navigation, with
a DM of -navigation skill. If such a mishap does occur, the ship will be 2D times 1 million km further from [the destination]."

 

[flykiller]

So, I'd like to try and find ways to make this a little more interesting for my player

something official, or just anything?

 

[Spinward Scout]

I did something a long time ago (the date on the post is Sept 2002) with Astrogator Calculations. I'm wondering if something that I or someone else posted there might be helpful for you. It was for T20 originally, if I remember.

I've also modified it a bit since, so if it interests you, let me know.

 

[Hal]

something official, or just anything?

When something doesn't exist in a rule set or the rule that does exist, kind of stinks, I'm not above creating what I need or shy about creating house rules

 

[Hal]

There are rules for jump accuracy in CT Beltstrike, Folder 1 "Lodes of Adventure":

"A mistake in navigation could place the shlp further from the
desired location (but never closer in). Commercial ships rarely make
such mistakes, but they may occur with private vessels. Throw 10 +
for a slip in computations to cause a mistake in navigation, with
a DM of -navigation skill. If such a mishap does occur, the ship will be 2D times 1 million km further from [the destination]."

Too bad I never purchased belt strike back in the day, or I'd have used it. 3 million km is about 1 A.U. So an inaccurate jump would have been between .33 to 2 A.U. In range. Something to consider.

 

[Hal]

I did something a long time ago (the date on the post is Sept 2002) with Astrogator Calculations. I'm wondering if something that I or someone else posted there might be helpful for you. It was for T20 originally, if I remember.

I've also modified it a bit since, so if it interests you, let me know.

When I get home, I'll look at the thread - thanks

 

[flykiller]

I'm not above creating what I need or shy about creating house rules

I'm hip. well I have a task system that covers navigation, if you want I'll post it.

 

[whartung]

Too bad I never purchased belt strike back in the day, or I'd have used it. 3 million km is about 1 A.U. So an inaccurate jump would have been between .33 to 2 A.U. In range. Something to consider.

An A.U. is ~155M km

 

[Hal]

I'm hip. well I have a task system that covers navigation, if you want I'll post it.

Go for it. Ideas are always welcome.

I was having a talk with a player about some of the issues I was having trying to make the random die rolls represent something "rational" without getting a migraine headache. So I came up with one basic idea, and he came up with a refinement for that basic Idea...

Worlds with a population under a given value - are not actual MEMBER worlds. They come under the heading of colonies of sorts, and until they are given their first "Noble", they come under a different jurisdiction than member worlds do. So a world with a population rating of 4 and a corporate government is a glorified mining camp (so to speak) while a world with a population of 4 with a democracy would be seen more as an to form a colony. That is when the player mentioned that maybe a limited charter defines the truly temporary occupation of worlds, and have to be renewed every year, while colonies have a simple charter - intending to become a member world eventually.

The scout service is used to check on the colonies to insure that they are functional and to be on hand from time to time if there is ever an emergency. It isn't their "ONLY" function so much as an afterthought.

The whole point for me as a GM is to try and "live" in that universe in my own imagination so I can bring it alive for my players. When I looked at the world Ianic back in the day, I saw how many trade partners it had, and that anyone who arrived at it, would have to refuel at a nearby gas giant (there's laws about taking a scarce life giving resource from a world!). So some genius figured out that maybe he could build a refueling corporation. Price the cost of the fuel transports that ran between the gas giant and the main world, price a space station that accumulates the raw fuel from the gas giant (automated refueling shuttles to avoid radiation issues and save lives) and presto... a company that can present a business model projected revenues based on projected traffic, along with a solid presentation of construction costs for the space station, the "Boats" carrying the fuel with onboard refining equipment, underground fuel tanks, and even fuel tankers on the planet side to dispense fuel to customers. Heck, thanks to GURPS FAR TRADER, there were even rules on how to handle an initial stock offer and how many people might buy into it on a week by week basis. Those "exercises" made me realize that sometimes starports aren't built necessarily by the SPA, but by people who see a product/service they can offer, and after it takes off, the SPA takes it over after buying them out. I fleshed out the ship designs - calling one a plecosomas (Spelling?) named after a sucker fish that scrapes off alge from smooth surfaces. I forget now what I called the other classes, but posted the information somewhere at some point in time. Maybe even here.

So, sharing ideas is a GOOD thing from my perspective.

I read the link that was related to T20 rules, so it sort of didn't make much sense to me. I stopped playing D&D in the 80's because I wasn't happy with the rule set. But I understand that some of the material as reference sort of hewed to the standard set by CT.

Well, I should be in bed, so I'll catch you guys tomorrow I'm sure.

 

[Hal]

An A.U. is ~155M km

OOps! You're right! Why I thought 300,000 is my bad! I guess I had it confused with the speed of light in Km. Color me embarrassed.

 

[Whipsnade]

Worlds with a population under a given value - are not actual MEMBER worlds. They come under the heading of colonies of sorts, and until they are given their first "Noble", they come under a different jurisdiction than member worlds do. So a world with a population rating of 4 and a corporate government is a glorified mining camp (so to speak) while a world with a population of 4 with a democracy would be seen more as an to form a colony. That is when the player mentioned that maybe a limited charter defines the truly temporary occupation of worlds, and have to be renewed every year, while colonies have a simple charter - intending to become a member world eventually.

That's quite like the situation IMTU.

While those worlds don't yet have a "resident" noble, they are gathered into "counties" and assigned to a count or viscount. (GT and T5 gave those two nobles a different job.)

My idea was that those nobles would manage those "backwater" and "no account" worlds' interactions with the Imperial bureaucracy and represent them at the duchy level. Such nobles would also have a baron or three to assist them, usually of the honor type, usually more comfortable with the "commons" than many Imperial nobles are, and usually found in "rougher" places doing "rougher" things too.

Ready made patrons and adventurers as it were.

 

[Hal]

That's quite like the situation IMTU.

While those worlds don't yet have a "resident" noble, they are gathered into "counties" and assigned to a count or viscount. (GT and T5 gave those two nobles a different job.)

My idea was that those nobles would manage those "backwater" and "no account" worlds' interactions with the Imperial bureaucracy and represent them at the duchy level. Such nobles would also have a baron or three to assist them, usually of the honor type, usually more comfortable with the "commons" than many Imperial nobles are, and usually found in "rougher" places doing "rougher" things too.

Ready made patrons and adventurers as it were.

While GURPS NOBLES and T5 have similarities - there are differences involved that have me scratching my head. It will make for fodder for us to talk about privately or maybe not so privately in another thread in CotI. Maybe "in my traveller universe" perhaps?

When I try to rationalize what is in T5 as far as lands held as fiefs, I find it interesting the number of actual "small hexes" are required for the Landed nobility. With half held on the planet proper, but the number being calculated by the rank of the Noble, it makes me wonder by what mechanism these lands are reserved. When a world joins the Imperium - is it automatically required to hand over a given amount of land for Imperial use - ONLY by the number of nobles assigned to the world at that time? If the world acquires a new noble, is it required then to give up lands to the imperial reservation - or were such lands already handed over when the world joined the Imperium?

With GURPS Nobles, some questions were potentially answered, and some that largely didn't fit with my concept of Nobility in the Imperium. It is the nature of the beast (so to speak) that people in power tend to work to keep what power they have and maybe acquire more. Some for good, some for bad - but the Nobility has to have special perks that set them above others or they're just "others" with a different name. What those perks are - don't make sense unless some real power comes with it. Having a Knight as an acting liaison interface between a world and the Imperium may have some advantages, but where does that knight go from there? Do the fortunes of that Knight's family rise with the growth of the world in question? <shrug> No one knows because it wasn't given much thought in the grand scheme of things. Largely I suspect, because there are SOME things that are strictly "IMTU" and developers of the game lines didn't want to write canon that would leave fans howling at how it violated their campaign universes they had set up over time. But, ideas being what they are - sometimes someone outlining what they did, and even WHY they did it, can provide thoughtful fodder for other GM's to either steal or steal with modifications.

Eventually, I will likely set up some rules for Inaccurate jumps by creating a table. For those of us who don't like Jump masking (such as myself) it might be useful as a secondary means for extending time in Normal space much like jump masking does. A rose by any other name kind of thing...

 

[Whipsnade]

While GURPS NOBLES and T5 have similarities - there are differences involved that have me scratching my head. It will make for fodder for us to talk about privately or maybe not so privately in another thread in CotI. Maybe "in my traveller universe" perhaps?

The IMTU forum would be best IMHO.

I've already partially derailed a few of Robject's threads so it would be for the best to "quarantine" me!