Synchronized Jumps

[phavoc]

Freighters are expensive today, and with much shorter operational life spans. The Benjamin Franklin container ship cost $151 million dollars, has a crew of 27 and can carry 18,000 TEU (or about 9,000 40ft containers). Traveller doesn't account for economies of scale, or at least the rules do not because players don't operate 50,000 Dton freighters on their own (and the crew guidelines don't support civilian ship operations very well either).

Economics would not allow the Traveller economic system to operate. 1 CR on a HiPoP TL15 world wouldn't have the same buying power as on a Tl2 world. Where is the discount for purchasing tickets in advance? Where are the options for liners and freighters to sell passage at the last minute at a discount? By the rules they don't exist, unless you want to put them in there yourself. I do understand you can't, and really don't want, that level of detail in a game. What I'm saying is that the system is artificial and there are places it could be tweaked without detracting from the game. It's just a matter of deciding to detail things out or not.

 

[AnotherDilbert]

Freighters are expensive today, and with much shorter operational life spans. The Benjamin Franklin container ship cost $151 million dollars, has a crew of 27 and can carry 18,000 TEU (or about 9,000 40ft containers). Traveller doesn't account for economies of scale, or at least the rules do not because players don't operate 50,000 Dton freighters on their own (and the crew guidelines don't support civilian ship operations very well either).

A 100 kT J-3 freighter carrying 18000 TEU ≈ 55000 dT cargo costs Cr20 billion. 100 times more expensive ships means much more expensive freight rates.

 

[Reynard]

"So I'm scratching my head a bit to understand what you are trying to say here."

Well then we are actually looking at a situation but going in two directions. It's beginning to sound like you mean all ships should have jump synching integral so it's a common event to jump in groups, I assume, to make opposition space encounters obsolete. Probably be easier to make jump automatically 148 hours. I might need a better elaboration.

 

[phavoc]

"So I'm scratching my head a bit to understand what you are trying to say here."

Well then we are actually looking at a situation but going in two directions. It's beginning to sound like you mean all ships should have jump synching integral so it's a common event to jump in groups, I assume, to make opposition space encounters obsolete. Probably be easier to make jump automatically 148 hours. I might need a better elaboration.

Integral from the point being that any ship, or set of ships can do it. My original proposal was that there was some restrictions - time per parsec and the ships needed to halt relative to one another so that the calculations were more clear. So existing jump software would be used with no special equipment needed. IF you wanted to do it while underway, like military vessels would want to, THEN you would ADD to the them additional costs to account for the added complexity. All I'm saying is that jump capable ships should, by default, be able to do it with some extra work (but not days).

 

[Nathan Brazil]

With regards to the OTU:

In the Agent of the Imperium Novel, active military vessels had no ability to synchronize their drives to jump and arrive together at the same time. The best they could achieve in the novel was to be within a 2% variance of the 168 hour window of jump. This was done by "tuning" the drives (whatever that process is).

I do not know if you read the novel, but if you accept AOTI whole cloth, introduction a program or system or process that allows better synchronization makes it YTU at least or consider the best the 3I had in 621 was TL D. Your new synchronization was invented later and/or requires a higher TL to discover. Else the military would already be using it back then.

 

[Reynard]

Sounds like 'tuning' the engine is the Engineer roll in the jump synching sidebar.

 

[phavoc]

With regards to the OTU:

In the Agent of the Imperium Novel, active military vessels had no ability to synchronize their drives to jump and arrive together at the same time. The best they could achieve in the novel was to be within a 2% variance of the 168 hour window of jump. This was done by "tuning" the drives (whatever that process is).

I do not know if you read the novel, but if you accept AOTI whole cloth, introduction a program or system or process that allows better synchronization makes it YTU at least or consider the best the 3I had in 621 was TL D. Your new synchronization was invented later and/or requires a higher TL to discover. Else the military would already be using it back then.

No, I haven't read the novel. I'm still miffed at the money I spend to kickstart the cruddy T5 book I got and I'm not looking to give Miller any more money for the time being. I'm voting with my pocketbook.

The tuning issue is something, though allowing only military drives to do so when there is no difference between civilian and military ships, per the rules, then I'd have to say the jury is still out.

I would agree with Reynard that engine tuning would be more of an engineering task than navigational or piloting.

 

[Nathan Brazil]

Again I don't have HG2, but I would point these two things out

A.Even with drives tuned, synchronized fleets are composed of individual ships.
The novel points out based on decades/centuries long statistical observation, that individual ship arrival of a "synchronized" fleet can be plotted against on a nice regular bell curve. Starting with a one ship, a few more a few minutes later, increasing till the largest group leaves jump space at exactly the 168th hour. Then less ships and less until none. Because the curve is well known, total fleet size can be fairly well estimated, as well as the 168th hour as more and more data points are recorded.
This is likely another specific reason why attacking fleets never just jump directly to the 100 diameter limit of a target planet and go in shooting. That and the dry jump fuel tanks. The other implications on fleet action, I leave for another post after people let this sink in.

B.Based on the curve above. I can see the defensive implications of previous posts about anti-piracy. If corsairs know the bell curve, they will not attack fleets of commerce ships. However, for you speculators, is the time taken to tune your ships to all arrive more or less the same time worth it or not from a money standpoint? Market values of goods might change at the destination if you wait too long,

 

[phavoc]

I'm not a mathematician by any means, but the bell curve idea seems a bit implausible to me because by definition each ship experiences a randomness unique to it. Therefore you can't average that out into a bell curve because you have no commonly distributed data sets upon which to model.

That's like trying to plot the bell curve for a coin flip. You have a 50-50 chance eacheck time. If there IS a bell curve for ships arriving, then that would be attributable to knowing the averages of all ships leaving jumpspace. But the statement on jump travel says otherwise.

 

[Reynard]

Each ship does experience a 6D hour randomness but all ships in that population will soon show an overall pattern as a summation of their bell curves so you can determine the breakdown of most probable exit times for all the ships. Accurate enough to set your plans on. I could dig out my Zar and explain in in painful detail... but I'll spare the universe.

 

[AnotherDilbert]

I'm not a mathematician by any means, but the bell curve idea seems a bit implausible to me because by definition each ship experiences a randomness unique to it. Therefore you can't average that out into a bell curve because you have no commonly distributed data sets upon which to model.

I think the probability distribution for each ship is bell shaped. It is often given as 140 + 8D hours. Each die has a uniform distribution, but the sum of many dice has a bell shaped distribution.
http://anydice.com/program/d89 (click on Graph for a better view.)

 

[Reynard]

148 + 6D. Range of 154 to 184. The mean (top of the bell curve) is 169 hours to exit.

The probability of each number between 154 and 160 is less than 1% as is every number between 178 an 184 so these hours to exit are very improbable. The probability to exit at the hours of 168, 169 and 170 is 9% each, 27% of all exit hours in the range. In other words, they know, out of 100 ships, 9 will hit on the nose while 27 will be within +/- one hour and so forth. T5 actually has a table showing the probability distribution for 6D. Plug in any number of ships.

Having the ability to have ships synch in within 6 minutes is astounding! Having any group of ships without cost able to do this completely rewrites Traveller. That is the ultimate Munchkin. Synching was written in that sidebar to be a province of the military. I believe it should be left there with only very extraordinary circumstances to allow any other group us it.

 

[AnotherDilbert]

Oops, yes, 148 + 6D, thanks. I wonder where I got 8D from?

 

[phavoc]

148 + 6D. Range of 154 to 184. The mean (top of the bell curve) is 169 hours to exit.

The probability of each number between 154 and 160 is less than 1% as is every number between 178 an 184 so these hours to exit are very improbable. The probability to exit at the hours of 168, 169 and 170 is 9% each, 27% of all exit hours in the range. In other words, they know, out of 100 ships, 9 will hit on the nose while 27 will be within +/- one hour and so forth. T5 actually has a table showing the probability distribution for 6D. Plug in any number of ships.

Having the ability to have ships synch in within 6 minutes is astounding! Having any group of ships without cost able to do this completely rewrites Traveller. That is the ultimate Munchkin. Synching was written in that sidebar to be a province of the military. I believe it should be left there with only very extraordinary circumstances to allow any other group us it.

Yeah, this is why I didn't go into higher math. It makes the universe go round, but blech. Sometimes I think it's a philosophical argument on odds. One coin toss, it's 50/50 change of heads or tails. Do it enough times and you get a probability graph... except you should still get, in my mind at least, a 50/50 chance each time you toss the coin. The only issue I would have with the emergence table is that you have no idea how many ships are in the group, and you only have that data set to make your assumption. It could be that those 6 ships are all that are in the group, cause that's possible with the odds... Ugh... math.

The rest, I still don't see it just as the military, at least under MGT rules, since everyone basically has milspec equipment and ships.

 

[rust2]

The novel points out based on decades/centuries long statistical observation, that individual ship arrival of a "synchronized" fleet can be plotted against on a nice regular bell curve. Starting with a one ship, a few more a few minutes later, increasing till the largest group leaves jump space at exactly the 168th hour. Then less ships and less until none. Because the curve is well known, total fleet size can be fairly well estimated, as well as the 168th hour as more and more data points are recorded.

True, but this is still only the highest probability based on statistics. While this would have a lower probability and therefore be rare, it could just as well happen that the arrival of a specific fleet has no similarity with a bell curve at all. Just think of the bell curve for 2d6, while a result of 7 has the highest probability, you can still end up with six dice rolls with three times the result 2 and three times the result 12.

 

[AnotherDilbert]

The more dice you roll = the more ships jump together, the less likely outlier results become.

Example: If we roll one die all results are equally likely, the chance of rolling a 6 is 1/6. If we roll two dice the chance that both are 6s is 1/36. If we roll 3 dice the chance of all 6s is 1/216. If we roll 100 dice:
http://anydice.com/program/5a1
The chance of rolling under 300 or over 400 is very, very small.

In the same way if a few ships jump together the result is pretty random. If a few hundred ships jump together the distribution of arrival times is pretty predictable, even if it is completely random which ship arrives first.

 

[Nathan Brazil]

True, but this is still only the highest probability based on statistics. While this would have a lower probability and therefore be rare, it could just as well happen that the arrival of a specific fleet has no similarity with a bell curve at all. Just think of the bell curve for 2d6, while a result of 7 has the highest probability, you can still end up with six dice rolls with three times the result 2 and three times the result 12.

The more dice you roll = the more ships jump together, the less likely outlier results become.

It is not my primary training but my career as a programmer analyst for 20 years has included light data analysis like z-scores and confidence levels. Another Dilbert, you absolutely incorrect. The more dice rolls = more data points. If you make one roll or a very few rolls, it is hard to tell the curve. As rust2 says, when you deal with a small distribution, yes you could end up with a situation exactly as he describes.
In the novel we are dealing with the final battle of the original Civil War in 621. The invading fleet has 80 ships. The way it goes is that despite tuning and with the fleet jumping out at the same time, arrival is uncertain for each ship. From a gaming standpoint, it would be like each ship has to roll 2d6 individually to determine arrival time.

The Second Expeditionary Fleet numbered 402 ships, but that count was misleading. More than half were minors, auxiliaries, and tenders. The only ones that anyone counted were the capitals: a variety of battleships and dreadnoughts and siege engines.
Some were fresh from the victories of the Second Frontier War and were built to express current fighting doctrine. Others had joined the expedition en route and ranged from modern to obsolete. The total for the only ships that had a chance was eighty.
The laws of chance govern time-in-jump. Long ago, navies learned to tune their drives to near perfection: 168 hours, plus or minus a fiftieth, but the result is still a bell curve around the intended arrival time: of eighty ships, the first dribbles would appear three hours before, peaking at a quarter of them precisely on time, and then dribbling back to only a few by the end of the next three hours.
The strategic plan took all of this into account. - Agent of the Imperium pg 203

 

[Nathan Brazil]

This was what I was going to point out is integral to Imperial Navy activity. In war you have to know what you are up against. This section from the book shows how detailed they rely on the curve and they can determine fleet composition based on a few some data points. Like you said rust2 if it is only a few ships, you can have weird outlier results, but more data points bring more predictability. it is implied in the first underlined part they are aware your outlier. Navy battles are won and lost even before the entire fleet arrives.

The graphic showed the icons of the three new arrivals mapped against a bell curve.
“Their time in jump was remarkable; they all broke out within three minutes of each other. That is very good drive tuning.”
As they watched, another icon showed on the screen and the bell curve expanded...
...“What squadron size are you using?”
The tech pointed to a number, “Standard six ships, sir.”
“Something’s not right. Are there any auxiliaries?”
“No, sir, just capitals. Snowcatess, She-Lynx, and Kokaari, then a siege, and now Uncompromising.”
“It is strange to have dissimilar classes in the same squadron."
“Increase squadron size to two.”
The bell curve widened.
“Now three.”
The humped line on the screen widened more.
“Sir, there’s a new arrival.”
“Map the curve to fit what we have so far.”
The screen now showed a scatter of ship icons with names attached, and a cloud of grey possibles extending into the future.
The best fit predicted ten squadrons: some sixty well-armed dreadnoughts and another dozen carriers and sieges.
The Lieutenant walked the five steps to his Commander and showed a tablet with the prediction, who snatched it to immediately show the Admiral in mid-conversation.
“Battle Stations!” - Agent of the Imperium pg 204-205

 

[AnotherDilbert]

Another Dilbert, you absolutely incorrect.

It's possible, that has certainly happened before.

It's also possible you have misunderstood me. I do not understand your objection. I thought I was basically restating the law of large numbers.

"The result" in my post is the measured distribution of actual die rolls, or actual ship arrival times. So an outlier result is e.g. that all die rolls are 6s, or that all ships arrive in the first hour.

I hope that we can agree that as more ships jump together, the less likely it is that all ships arrive in the first hour?

 

[Nathan Brazil]

I apologize I was being cranky, I was reading this at 3AM local time. Yes, you are correct about the law of large numbers. Within the OTU, as the segments I quoted show, there is some factor that results in a distribution that is not even across a time span centered on a mean reentry of 168 hours, plus or minus.

What are those factors?
Traveller 5:
"Jump involves some logical disconnects:
vast amounts of power are required to transition to jump space, but almost no power is required to move through it;
the time spent in jump space has little or no relation to the distance travelled; and
sometimes, jumpspace does not operate in logical or predictable ways." (page 333)

Agent of the Imerium:
Jump Space is in fact affected by living minds.
One situation is if one person looks out a window to see jump space, they see random patterns and flashes and feel uncomfortable (and maybe go insane). The more people look out the same portal, the view of jump space becomes more and more a uniform grey with less discomfort.
The other more definite one is the Zhodani deathtrap chapter where the Zhodani do really, really, freaky stuff involving either jump space, Not Foam, or both. A Navy ship misjumps 20 parsecs, the Zhodani anticipated the arrival of the ship because they claim to have caused it. Yes that's right kids....